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  1. Ana Sayfa
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Yazar "Yildizhan, Hasan" seçeneğine göre listele

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    A Multi-Country Statistical Analysis Covering Turkey, Slovakia, and Romania in an Educational Framework
    (Mdpi, 2023) Pekdogan, Tugce; Udristioiu, Mihaela Tinca; Puiu, Silvia; Yildizhan, Hasan; Hruska, Martin
    This paper uses hierarchical regression analysis, a statistically robust method, to explore the correlations between two meteorological parameters and three particulate matter concentrations. The dataset is provided by six sensors located in three cities from three countries, and the measurements were taken simultaneously for three months at each minute. Analyses and calculations were performed with the Statistical Package for the Social Sciences (SPSS). The results underscore that the complexity of air pollution dynamics is affected by the location even when the same type of sensors is used, and emphasize that a one-size-fits-all approach cannot effectively address air pollution. The findings are helpful from three perspectives: for education, to show how to handle and communicate a solution for local communities' issues about air pollution; for research, to understand how easy a university can generate and analyze open-source data; and for policymakers, to design targeted interventions addressing each country's challenges.
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    Alternative work arrangements: Individual, organizational and environmental outcomes
    (Cell Press, 2023) Yildizhan, Hasan; Hosouli, Sahand; Yilmaz, Sidika Ece; Gomes, Joao; Pandey, Chandan; Alkharusi, Tarik
    Flexible working models are widely used around the world. Furthermore, several countries are currently transitioning to a 4-day workweek. These working models have significant effects on organizational behavior and the environment. The study investigates the employees' attitudes and behaviors toward flexible working and 4-day workweek and the impact on the environment. The semi-structured interview method was used in the study to determine employee attitudes and behaviors; the carbon footprint calculation method was used to determine the environmental impact of a 4-day workweek. According to the study's findings, it has been discovered that there would be a positive impact on socialization, happiness, stress factor, motivation, personal time, mental health, comfort, work-life balance, time-saving, willingness, positive working environment, personal time, and physical health. Furthermore, a 4-day workweek reduced commuting emissions by 20%, resulting in a 6,07 kg tCO(2)e reduction per person. As a result, the study attempted to draw attention holistically to the positive effects of the flexible working model and 4-day workweek. The study is intended to serve as a tool for decision-makers and human resource managers.
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    Application of machine learning for solar radiation modeling
    (Springer Wien, 2021) Taki, Morteza; Rohani, Abbas; Yildizhan, Hasan
    Solar radiation is an important parameter that affects the atmosphere-earth thermal balance and many water and soil processes such as evapotranspiration and plant growth. The modeling of the daily and monthly solar radiation by Gaussian process regression (GPR) with K-fold cross-validation model has been discussed recently. This study evaluated different neural models such as artificial neural network (ANN), support vector machine (SVM), adaptive network-based fuzzy inference system (ANFIS), and multiple linear regression (MLR) for estimating the global solar radiation (daily and monthly) with K-fold cross-validation method. For the appropriate comparison of the models, the randomized complete block (RCB) design applied in the training and test phases. Also, different data sets were evaluated by K-fold cross-validation in each model. The results showed that radial basis function (RBF) model has the lowest error for estimating the monthly and daily solar radiation. In this study, the result of RBF was compared with the GPR models. The conclusion indicated that RBF methodology can predict solar radiation with higher accuracy relative to the GPR model. The results of yearly solar radiation estimation (2009-2014) showed that the RBF model can estimate solar radiation with the MAPE and RMSE of 5.1% and 0.29, respectively. Also, the coefficient of correlation (R-2) between actual and estimated values throughout the year is 98% and can be used by the engineers and other researchers for solar and thermal applications.
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    Appraisal of energy loss reduction in green buildings using large-scale experiments compiled with swarm intelligent solutions
    (Elsevier, 2023) Moayedi, Hossein; Yildizhan, Hasan; Al-Bahrani, Mohammed; Le Van, Bao
    Today, the issue of energy efficiency is a major one in global politics. The external environment, particularly the wind speed and outside air temperature, determines the thermal burden the cold outside air places on a building's interior. The heat load of a building is influenced by several factors, including the wall's heat transfer coefficients (W/mK), the coating material (W/mK), the inside temperature (degrees C), and the outside temperature (degrees C), and the temperature of external surface (degrees C). In this investigation, we undertake a comprehensive assessment, evaluation, and comparing the performance of two unique artificial approaches (BSA and COA) utilized for anticipating heat loss in green buildings; the optimum way is then identified depending on the R-2 and RMSE criteria. The outcomes demonstrate that BSA and COA have R-2 values of (0.97038 and 0.90158) and (0.9919 and 0.94239) in the training and testing phases. Additionally, the RMSE values for BSA and COA in the training and testing stages are (0.02541 and 0.08616) and (0.01336 and 0.06662), correspondingly. Also, the estimated MAEs (0.019055 and 0.0097193) denote a low level of training error for both methods. Regarding R-2, RMSE and MAE values, the COA predicts energy loss more accurately.
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    Approximating heat loss in smart buildings through large scale experimental and computational intelligence solutions
    (Taylor & Francis Ltd, 2023) Ben Khedher, Nidhal; Mukhtar, Azfarizal; Yasir, Ahmad Shah Hizam Md; Khalilpoor, Nima; Foong, Loke Kok; Le, Binh Nguyen; Yildizhan, Hasan
    The attainment of energy sustainability in the building sector can be realised by implementing a green building programme, which has grown significantly over the last thirty years. Green building is considered a technical and management strategy within the building and construction industries. Many different prediction methods, both complex and simple, have been put out in recent years and used to solve a wide variety of issues. Several case studies have highlighted factors that impede energy and resource usage in green buildings. The utilisation, trends, and consequences of wall and thermal insulation materials are examined. The main scope of this investigation is to predict buildings' heat loss by applying artificial neural networks according to the heat transfer coefficients of walls and coating materials, as well as indoor, outdoor, and external surface temperatures. The data has been normalised and presented to two selected neural networks (Harmony search (HS) and particle swarm optimisation are used and contrasted (PSO)). For evaluating the accuracy of models, two statistical indexes are used (R (2) and RMSE). Model performance of PSO-MLP is shown by R (2) amounts of 0.97055 and 0.87381, respectively, and RMSE amounts of 0.02534 and 0.09685. Similarly, HS-MLP model accuracy is also indicated by R (2) amounts of 0.93839 and 0.84176 and RMSE amounts of 0.03635 and 0.10753. The analysis in this paper shows that PSO-MLP predicts heat loss with higher accuracy and improved performance.
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    Assessment of Whole Milk Powder Production by a Cumulative Exergy Consumption Approach
    (Mdpi, 2023) Ucal, Esmanur; Yildizhan, Hasan; Ameen, Arman; Erbay, Zafer
    The production of food is a sector that consumes a significant amount of energy and encompasses both agricultural and industrial processes. In this study, the energy consumption of whole milk powder production, which is known to be particularly energy-intensive, was examined. The study used a cumulative exergy consumption approach to evaluate the overall production process of whole milk powder, including the dairy farm (raw milk production) and dairy factory (powder production) stages. The results showed that raw milk production dominated energy and exergy consumption and carbon dioxide emissions. An amount of 68.3% of the total net cumulative exergy consumption in the system was calculated for raw milk production. In the dairy factory process, the highest energy/exergy consumption occurred during spray drying, followed by evaporation and pasteurization. In these three processes, 98.3% of the total energy consumption, 94.6% of the total exergy consumption, and 95.7% of the total carbon dioxide emissions in powder production were realized. To investigate the improvement potentials in the system, replacing fossil fuels with renewable energy sources and using pasture feeding in animal husbandry were evaluated. While using alternative energy sources highly influenced powder production, pasture feeding had a high impact on consumption in raw milk production. By using renewable energy and pasture feeding, the exergy efficiency, cumulative degree of perfection, renewability index, and exergetic sustainability index values for the overall process increased from 40.5%, 0.282, -0.22, and 0.68 to 68.9%, 0.433, 0.65, and 2.21, respectively.
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    Assessment of window renovation potential in an apartment with an energy performance approach
    (Oxford Univ Press, 2024) Pekdogan, Tugce; Yildizhan, Hasan; Ahmadi, Mohammad Hossein; Sharifpur, Mohsen
    Windows are of great importance in improving the energy efficiency of buildings. It is possible to achieve this with the help of the regeneration of window design. The amount of energy used, the expense of heating and cooling, and the emissions of greenhouse gases that contribute to climate change can all be significantly reduced by improving the energy efficiency of windows. For this, computer modeling and BIM-based simulation programs provide significant timesaving in simultaneously evaluating design variations' visual and thermal results. This study selected a four-story residential building to analyze the energy load and thermal comfort of the windows redesign and examine the energy-saving potential for residential buildings. To analyze the renewed window design strategies, a four-story apartment building is selected as a case study in Izmir/Turkey (38 degrees 4 ', 27 degrees 2 '). This apartment is built on a 90 m2 gross floor area. The existing indoor environmental conditions of the flat are generally observed as cool and low illuminated by the occupants, so the window design options must be compared and renewed. As the first option, current conditions are simulated. The second option is to simulate different patterns for window-to-wall ratio (WWR). Moreover, the third option is to simulate different types of glass in each window. Currently, the WWR of the selected flat in the north, east and south directions is around 10%. But more is needed to provide daylight to the apartment. This article used Autodesk Revit and Green Building Studio simulations to investigate WWR and glass types and evaluate energy use intensity's (EUI) impact. As a result, this study shows that a 10% WWR on all building facades leads to an EUI of 993.9 MJ/m2/year. In contrast, increasing the WWR to 95% significantly increased EUI, reaching 2121 MJ/m2/year. In addition, it has been shown that the use of low U-value glasses, such as translucent wall panels and super-insulated three-pane clear Low-E, can provide energy savings of up to 5% per year, and especially the super-insulated three-pane Low-E glass type provides the highest efficiency on all facades.
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    Beyond direction-agnostic assumptions: Direction-integrated models for asymmetric falling film thickness and heat transfer under multidirectional vapor shear
    (Pergamon-Elsevier Science Ltd, 2026) Zhao, Chuang-Yao; Li, Qiong-Tao; Jia, Chen-Yi; Zhang, Fang-Fang; Qi, Di; Yildizhan, Hasan; Jiang, Jun-Min
    The orientation of vapor streams in falling film evaporators (FFEs), determined by tube bundle configurations, plays a critical role in shaping liquid film hydrodynamics and heat transfer performance. Conventional models adopt direction-agnostic assumptions, averaging vapor shear effects and introducing significant errors in localized predictions. This study proposes a direction-integrated framework that explicitly incorporates vapor orientation as a governing parameter, capturing the asymmetric effects of multidirectional vapor shear on film thickness and heat transfer. The proposed correlations are validated against a broad range of benchmark data, achieving 80 % of film thickness predictions within +25 % error, over 86 % of local heat transfer coefficients within +20 %, and all average values within +5 %. Comparative analysis shows strong agreement with experimental and numerical results under gravity-driven, laminar conditions. Vapor directionality is shown to significantly alter heat transfer along the tube periphery, especially between upper and lower regions. These findings enhance the predictive reliability of FFE modelling and provide valuable guidance for optimizing evaporator design and improving energy efficiency in industrial applications.
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    Bioclimatic comfort and solar responsive urban design in the traditional street texture of Diyarbakir's Suriçi region
    (Nature Portfolio, 2026) Gider, Kubra Suna; Ergin, Sefika; Yildizhan, Hasan; Ameen, Arman
    People in urban areas (such as streets, parks, semi-open and enclosed spaces) are exposed to varying microclimatic conditions. These conditions change depending on environmental characteristics and directly affect individuals' bioclimatic comfort levels. The lack of climate-responsive urban planning exposes inhabitants to uncomfortable thermal stress. Establishing climate-sensitive thermal comfort conditions at the micro scale is therefore essential for creating more livable urban environments. In hot-arid climates, kabalt & imath;s, roofed passages integrated into the street network, are among the spatial elements that influence pedestrian thermal comfort. However, there is limited knowledge in the literature regarding the thermal performance of these shaded structures, which provide both protection from solar radiation and shelter from rain and wind. This study aims to reveal the impact of kabalt & imath;s, as traditional urban elements in hot-arid regions, on bioclimatic comfort, and to contribute to the development of climate-responsive urban design strategies. Due to the scarcity of research on the thermal performance of kabalt & imath;s, the findings of this study provide new insights into climate-adaptive design solutions within traditional street networks and serve as a guide for urban planning practices. The research was conducted in the historical district of Diyarbak & imath;r Suri & ccedil;i, focusing on six kabalt & imath;s and their surrounding streets located in the Ziya G & ouml;kalp, Abdaldede, and S & uuml;leyman Nazif neighborhoods. At a total of 19 measurement points, air temperature, relative humidity, and wind speed were recorded over the course of one year. Using the RayMan Pro software, Physiological Equivalent Temperature (PET) values were calculated, and Sky View Factor (SVF) values were determined for comparative analysis. The results indicate that the studied streets and kabalt & imath;s were exposed to varying degrees of heat and cold stress throughout the year. Shaded zones and kabalt & imath;s exhibited lower air temperature and PET values compared to other points. In this hot-arid setting, the presence of covered, shaded areas was found to be effective in reducing solar exposure and lowering thermal stress during summer months. The measurements further revealed that urban geometry, particularly building height and street width, influenced solar radiation access and wind speed, thereby affecting PET values. In addition, no direct correlation was observed between SVF and PET, highlighting the need to consider other parameters when assessing bioclimatic comfort.
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    Consumer purchasing behavior and its organizational evaluation toward solar water heating system
    (Elsevier, 2023) Celik, Onur; Yilmaz, S. Ece; Yildizhan, Hasan; Ameen, Arman
    Renewable energy sources are fundamental to a country's economic growth. Solar energy is one of these resources that has a favorable effect on economic growth. Turkey's solar energy industry is still in its early stages. Due to its location and degree of sunshine each year, the country has a great solar potential. Despite the huge potential, solar energy awareness and utilization are not widespread in all parts of Turkey. In order to identify the factors that affect consumers' decisions to utilize water heating systems, which is a sort of solar energy system, the purpose of this research is to examine these systems. In this study, all factors influencing consumers' decisions to acquire solar water heating systems were evaluated holistically for the first time. A questionnaire was used in the study, which is a quantitative research technique. The study identifies the variables that influence consumers' attitudes toward solar collector purchases and assesses the consequences from an organizational point of view. The study's results act as a guide for decision-makers. & COPY; 2023 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
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    Effect of post-deposition aluminizing on the corrosion and mechanical behavior of WAAM-fabricated stainless steel and Ni-based superalloy
    (Nature Portfolio, 2025) Gunen, Ali; Gurol, Ugur; Cakan, Ahmet; Kocak, Mustafa; Cam, Gurel; Yildizhan, Hasan; Alsaadi, Ahmed; Gomes, Joao
    The demand for corrosion-resistant and mechanically reliable metallic components in marine, chemical processing, and energy conversion industries has encouraged the integration of additive manufacturing into industrial production. Wire Arc Additive Manufacturing enables the fabrication of medium- to large-scale complex metallic structures at low cost; however, the high thermal input and layer-by-layer deposition commonly lead to elemental segregation, porosity, and nonuniform microstructures that degrade corrosion performance. This study investigates the influence of a post-deposition aluminizing treatment on the surface characteristics and corrosion behavior of stainless steel ER307 and nickel-based superalloy Inconel 625 produced by Wire Arc Directed Energy Deposition. Microstructural evolution, phase transformation, hardness distribution, and corrosion behavior in a 3.5% sodium chloride environment were examined through microscopy, X-ray diffraction, hardness testing, and electrochemical analysis. The aluminizing process generated localized surface porosity and limited non-uniformity aluminide coatings of approximately 40-50 mu m thickness, reduced surface roughness, and markedly improved surface hardness. Electrochemical assessments demonstrated substantial enhancements in corrosion resistance, including a 2.3-fold improvement for stainless steel and a 13.9-fold improvement for Inconel 625. These findings reveal that post-deposition aluminizing effectively mitigates intrinsic surface defects and microchemical heterogeneity, enabling significantly improved durability in chloride-containing environments. This work provides a straightforward and scalable strategy for enhancing the corrosion resistance of wire-arc-manufactured metallic structures and promotes their application in aggressive service conditions.
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    Effects of urban street geometry and traditional kabalti passages on building surface temperature in a hot-dry climate
    (Nature Portfolio, 2026) Ergin, Sefika; Gider, Kubra Suna; Seker, Ibrahim Halil; Yildizhan, Hasan; Ameen, Arman
    In hot climate regions, the direct impact of solar radiation on building surfaces, including heat absorption and storage, negatively impacts outdoor comfort and the living conditions of urban residents. This study investigates the impact of urban street geometry on building surface temperatures in a hot and dry climate, focusing on the traditional Suri & ccedil;i district of Diyarbak & imath;r. Measurements were conducted at 25 locations throughout the year along streets with varying sky view factor (SVF) values and within vaulted covered passages (kabalt & imath;s). In the study, a Testo 410-2 anemometer was used to measure air temperature and a thermal camera was used to measure surface temperature. The results show smaller daily surface temperature amplitudes in regions with lower SVF values and in kabalt & imath;s with an SVF value of 0. Measured surface temperatures reached as high as 58.8 degrees C at high SVF locations, while they remained around 30 degrees C in shaded kabalt & imath;s. The findings indicate that street geometry parameters such as building height, spacing, and orientation significantly influence microclimate conditions. Differences of up to 15-20 degrees C were observed between shaded kabalt & imath;s surface temperatures and other surface temperatures at measurement points where the SVF value was close to 1. Reducing SVF through design strategies such as the use of kabalt & imath;s and planting trees can improve outdoor thermal comfort in hot climates.
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    Examining effects of air pollution on photovoltaic systems via interpretable random forest model
    (Pergamon-Elsevier Science Ltd, 2024) Dudas, Adam; Udristioiu, Mihaela Tinca; Alkharusi, Tarik; Yildizhan, Hasan; Sampath, Satheesh Kumar
    Renewable energy plays a vital role in power generation and solar photovoltaic systems due to resource availability throughout the year. This work aims to investigate the impact of air pollutants and meteorological parameters on the performance of the photovoltaic systems locally, taking into consideration the advantages of the photovoltaic power potential of the SW part of Romania, where Craiova is located (average solar radiation intensity >1350 kWh/m(2)/year). This study is based on a one-year dataset provided by a sensor that monitors particulate matter concentrations, volatile organic compounds, dioxide of carbon, ozone, noise, formaldehyde and three climate parameters (temperature, pressure, and relative humidity). The research methodology applies an innovative interpretable random forest model emphasising the implications of air pollution for photovoltaic systems. The proposed machine learning model was trained to predict the particulate matter level in air based on the basic environmental variable measurements. The study presents six random forest models of varying complexity, which reach the accuracy of classification for the selected problem up to 99 %, and applies the Shapley Additive Explanations technique to interpret the decision-making model. The observation regarding the highest concentration of particulate matter occurring during cold months, which typically do not align with peak solar irradiance, underscores the importance of considering various environmental factors in solar energy planning. With its practical implications, this insight offers decision-makers valuable information about the feasibility of optimising solar energy generation despite seasonal variations in air pollution levels, directly addressing their needs and concerns.
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    Exergoenvironmental damages assessment in a desert-based agricultural system: A case study of date production
    (Wiley, 2022) Hesampour, Reza; Hassani, Mehrdad; Yildizhan, Hasan; Failla, Sabina; Gorjian, Shiva
    Developing countries, especially those in hot and dry areas, need more attention to achieve sustainable development as they apply excessive inputs in production processes. The present study aims to quantify the amount of environmental emissions and determine the most appropriate pattern of energy use in the date (Phoenix dactylifera L.) production process using thermodynamic analysis. The information was gathered through questionnaires and face-to-face interviews. From the results, cumulative exergy and energy demand for one Mg of date fruit production were calculated as 697 and 1640 MJ, respectively. Carbon dioxide emission was also measured at 197 kg Mg-1. Moreover, cumulative exergy consumption illustrated that manure and diesel fuel consumption is high, though diesel fuel and N consumption are given the most cumulative energy demand. Renewability indicator, cumulative degree of perfection, and the recoverable exergy ratio value of the date fruit production process were calculated as 0.62, 2.68, and 4.32, respectively. The date's chemical exergy value was calculated to be 14.96 MJ kg(-1). Dates have a high chemical exergy value because of their high carbohydrate content and lowwater content. As a result, crop chemical combinations have a direct impact on the production process. The total direct greenhouse gas emissions induced by the inputs consumption were 310.02 kg Mg-1. Emissions to air, soil, and water were 308.76, 5.60 x 10(-1) and 6.96 x 10(-1) kg Mg-1. In general, date production in Khuzestan province is partially renewable.
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    Experimental investigation of nonuniform PV soiling
    (Pergamon-Elsevier Science Ltd, 2024) Alkharusi, Tarik; Alzahrani, Mussad M.; Pandey, Chandan; Yildizhan, Hasan; Markides, Christos N.
    Photovoltaic (PV) module soiling, i.e., the accumulation of dust on PV module surfaces, poses several challenges to PV system performance. Among these challenges, the nonuniform deposition of soiling across the module surface has received scarce attention. Soiling is directly associated with an overall performance loss, but can also potentially give rise to localised hotspots that can lead to long-term PV module failure. Therefore, addressing the issues arising from this nonuniformity is not only important for optimising energy production, but also for enhancing system reliability, and ensuring the long-term operation of relevant power generation systems. In this study, the impact of nonuniform soiling on PV performance is investigated experimentally by examining soil deposition on the upper surfaces of low-iron glass samples. Samples positioned at four different tilt angles were collected on a monthly basis over a one-year study period. Since the horizontal samples were found to represent the worst-case conditions, the most soiled sample at horizontal tilt was divided into four zones, each housing a single monocrystalline solar cell and examined further. The findings reveal that the soiled sample experiences an average transmittance deterioration of 13% relative to a clean sample, and a maximum (relative) spatial variation of 4% between the four zones. These optical losses affect the amount of sunlight received by the cells, resulting in a power deterioration of similar to 6-7% per 5% drop in transmittance. The soiled sample experienced an average temperature rise of 2 degrees C, and an average power output (and efficiency) reduction of 30% relative to the clean sample, and a maximum (relative) spatial variation of 7% between the zones. The 30% average power loss measured in this nonuniform soiling case is more than double that which would be expected theoretically for a transmittance loss of 13% but from uniform soiling, so these results highlight the importance of addressing PV soiling for optimal PV performance, and of accounting for spatial soiling nonuniformity.
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    Falling film hydrodynamics and heat transfer under vapor shearing from various orientations
    (Aip Publishing, 2024) Zhao, Chuang-Yao; Li, Qiong-Tao; Zhang, Fang-Fang; Qi, Di; Yildizhan, Hasan; Jiang, Jun-Min
    Vapor shearing is a common issue encountered in the operations of falling film heat exchangers. The vapor stream effect depends on its orientation. This study investigates liquid film hydrodynamics and heat transfer performance under the influence of vapor streams from different orientations. The results indicate that both orientation and velocity of vapor determine the encountering time and position of the films on the tube's two sides. The liquid film thickness uniformity and the liquid column deflection vary significantly depending on the orientation and velocity of the vapor. Zones of accelerated liquid film, climbing liquid film, liquid stagnation, and transition of liquid film flow pattern are observed. The gradient of film thickness along the tube axis and the deflection in time-averaged peripheral film thickness increase as the vapor orientation varies from 0 degrees to 90 degrees and subsequently decrease as the vapor orientation varies from 90 degrees to 180 degrees. Vapor streams have more pronounced effects on time-averaged peripheral film thickness in regions close to the liquid inlet and outlet. Vapor streams result in changes in peripheral heat transfer coefficients toward the downstream side depending on the orientation and velocity of the vapor. The impact of vapor streams on the overall heat transfer coefficient does not directly correlate with the velocity of the vapor when maintaining the same orientation.
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    Forecasting ground-level ozone and fine particulate matter concentrations at Craiova city using a meta-hybrid deep learning model
    (Elsevier, 2024) El Mghouchi, Youness; Udristioiu, Mihaela T.; Yildizhan, Hasan; Brancus, Mihaela
    Air quality forecasting is vital for managing and mitigating the adverse effects of air pollution on human health, crops, and the environment. This study aims to forecast daily time series of ozone and fine particulate matter (PM) concentrations using a meta-hybrid deep NARMAX (Nonlinear Auto-Regressive Moving Average with eXogenous inputs) model. Two datasets were utilised: (a) data on meteorological parameters (temperature, air pressure, relative humidity) and air pollutant concentrations (particulate matter, ozone, dioxide of carbon, volatile organic compounds, formaldehyde) provided by a sensor model A3 situated in the centre of Craiova city, and (b) data on wind direction, wind speed, and sunshine duration provided by the National Meteorological Administration. The data sets covered a time interval from December 10, 2020, to January 05, 2024. Initially, a statistical analysis was conducted to assess the correlation between variables. Results revealed that ozone concentration is primarily influenced by meteorological variables such as temperature (r = 0.79), sunshine duration (r = 0.55), and relative humidity (r = -0.48), and secondarily by air pollution indicators including VOC (r = -0.34), PM concentrations (r = -0.34), and CO2 (r = -0.3). In the subsequent stage, thirteen Machine Learning (ML) models were employed in conjunction with an integral feature selection (IFS) method to identify the best combinations of predictor variables for predicting ozone and PMs. Finally, a deep NARMAX model was developed to forecast the next periods of ozone and PMs based on the optimal combinations identified earlier. Results indicated the selection of sixty best models for ozone forecasting and four best models for PMs. The R-2 values surpassed 0.97 for ozone and exceeded 0.8 for PMs, demonstrating the efficacy of the forecasting approach.
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    From Local Issues to Global Impacts: Evidence of Air Pollution for Romania and Turkey
    (Mdpi, 2024) Pekdogan, Tugce; Udristioiu, Mihaela Tinca; Yildizhan, Hasan; Ameen, Arman
    Air pollution significantly threatens human health and natural ecosystems and requires urgent attention from decision makers. The fight against air pollution begins with the rigorous monitoring of its levels, followed by intelligent statistical analysis and the application of advanced machine learning algorithms. To effectively reduce air pollution, decision makers must focus on reducing primary sources such as industrial plants and obsolete vehicles, as well as policies that encourage the adoption of clean energy sources. In this study, data analysis was performed for the first time to evaluate air pollution based on the SPSS program. Correlation coefficients between meteorological parameters and particulate matter concentrations (PM1, PM2.5, PM10) were calculated in two urban regions of Romania (Craiova and Drobeta-Turnu Severin) and Turkey (Adana). This study establishes strong relationships between PM concentrations and meteorological parameters with correlation coefficients ranging from -0.617 (between temperature and relative humidity) to 0.998 (between PMs). It shows negative correlations between temperature and particulate matter (-0.241 in Romania and -0.173 in Turkey) and the effects of humidity ranging from moderately positive correlations with PMs (up to 0.360 in Turkey), highlighting the valuable insights offered by independent PM sensor networks in assessing and improving air quality.
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    Green building?s heat loss reduction analysis through two novel hybrid approaches
    (Elsevier, 2023) Moayedi, Hossein; Yildizhan, Hasan; Aungkulanon, Pasura; Escorcia, Yulineth Cardenas; Al-Bahrani, Mohammed; Le, Binh Nguyen
    One of the key reasons for the performance discrepancy between a building's intended usage and the actual operation is Heat Loss, which describes a building's envelope efficiency during in-use circumstances. In this setting, the ANN models' use for energy analysis of green buildings has become more established. This research aims to anticipate the heat loss of green buildings utilizing two artificial neural network-based methodologies (ANN). In particular, TLBO and BBO are used and contrasted. Additionally, RMSE, MAE, and R2 are used to calculate an absolute error for predicting heat loss to gauge the accuracy of the findings. The suggested TLBO-MLP standard is a reliable method with a positive outcome (RMSE = 0.01012 and 0.05216, and R2 = 0.99536 and 0.9651). Also, according to the training error ranges of [-0.0006078, 0.01133] and [-0.00040708, 0.010181] and testing error ranges of [0.0004724, 0.068666] and [0.0021984, 0.057688] for BBO-MLP and TLBO-MLP, respectively, shows that the TLBO-MLP reaches the lower range of error and can predict the heat loss with higher accuracy and it could properly forecast the heat loss of building technologies. Even so, the BBO-MLP standard provides this research with satisfactory performance (R2 = 0.9943 and 0.95175, and RMSE = 0.01122 and 0.06112). To increase the precision of calculating the heat loss of buildings, specifically integrating them with optimization algorithms, further study is required.
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    How May New Energy Investments Change the Sustainability of the Turkish Industrial Sector?
    (Mdpi, 2023) Yildizhan, Hasan; Yildirim, Cihan; Gorjian, Shiva; Ameen, Arman
    Utilization of renewable energy in the Turkish industrial sector is becoming more important nowadays. The tendency toward renewable energy can be clearly seen with newly planned energy investments. The energy appearance of the Turkish industrial sector for past two decades and ongoing energy projects are discussed in this study with the help of sustainability indicators. The sustainability index is based on advanced exergy analysis and shows the environmental impact of production processes and measures the transformation of energy resources in the Turkish industrial sector. This index was approximately 2.03 in 2000 and it improved to 2.25 in 2008, and then remained constant with minor fluctuations until 2019. Depending on the fulfillment of the continuing fossil, nuclear, and recommended renewable energy investment scenarios, the sustainability index may change to between 1.96 and 2.17 by 2023. None of the ongoing investments will make a major improvement in the sustainability of the industrial sector; therefore, a major shift toward the use of more renewable energy is urgently needed. Establishing solar or wind energy microgrids plants may improve the sustainability indicators drastically, therefore, encouragement of their investments is very important.
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