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A NOVEL STOCHASTIC APPROACH TO BUFFER STOCK PROBLEM
(Turkic World Mathematical Soc, 2024) Hanalioglu, Z.; Poladova, A.; Gever, B.; Khaniyev, T.
In this paper, the stochastic fluctuation of buffer stock level at time t is investigated. Therefore, random walk processes X(t) and Y (t) with two specific barriers have been defined to describe the stochastic fluctuation of the product level. Here X(t) equivalent to Y (t) - a and the parameter a specifies half capacity of the buffer stock warehouse. Next, the one-dimensional distribution of the process X(t) has calculated. Moreover, the ergodicity of the process X(t) has been proven and the exact formula for the characteristic function has been found. Then, the weak convergence theorem has been proven for the standardized process W(t) equivalent to X(t)/a, as a -> infinity . Additionally, exact and asymptotic expressions for the ergodic moments of the processes X(t) and Y (t) are obtained.
Preparing eco-friendly composite from end-life tires and epoxy resin and examining its mechanical, and acoustic insulation properties
(Unimap Press, 2024) Abdulhameed, Jamal I.; Ali, Ahmed H.; Kara, Ismail H.; Mahan, Hamid M.; Konovalov, Sergey. V.; Al-Nedawi, Nada M.
The recycling of the enormous number of used tires that are discarded annually after the end of their service is a high-priority issue in order to conserve the environment and reduce the raw material costs of products, particularly in cases where high strength requirements are not necessary. In this study, crumbed tire rubber (CTR) was used as a filler with different weight fractions (10%, 20%, 30%, and 40%) to prepare CTR/epoxy composites. Mechanical, thermal, and acoustic insulation properties were tested to gather sufficient data on the development of these properties with increasing CTR content. The results indicate a decline in mechanical properties with increasing CTR content. The composite with 40 wt. % CTR showed a decrease in hardness, tensile strength, and flexural strength compared to neat epoxy by 75%, 70%, and 75% respectively. Additionally, the thermal conductivity of this composite was 36.3% higher than that of epoxy. Finally, the acoustic insulation test for the composite with a 40% CTR weight fraction showed improved sound insulation over a wide range of applied frequencies (0-10000) Hz.
EFFECT OF THE NANOFLUID FLOW AND EXTENDED SURFACES ON AN ABRUPT EXPANSION TUBE REGARDING THERMODYNAMIC IRREVERSIBILITY
(Begell House Inc, 2024) Pazarlioglu, Hayati Kadir; Ekiciler, Recep
Numerous scientists have examined circular dimpled surfaces, tubes, and other approaches for enhancing heat transfer. Moreover, the dimples' angle of attack has a substantial effect on the tube's flow and thermal features. This numerical study presents a novel approach to enhancing heat transfer rate in a tube subjected to constant heat flux by incorporating a surface dimpling strategy and evaluates three different tube layouts with elliptical dimpled fins for different working fluids such as DW and Al2O3/DW nanofluid (phi = 0.5-1.0%) by using ANSYS Fluent v2020R2 under laminar flow conditions. Under identical circumstances, the thermal performances of proposed designs are compared to those of a smooth tube, and the influence of the elliptical dimpled fin angle of attack on these parameters is determined for different Reynolds numbers (1000 <= Re <= 2000). When comparing the Nusselt number of a tube with/without elliptical dimpled fins, it is found that EDT 1 performed better. Lower Reynolds numbers are shown to result in a greater friction factor. Besides, elliptical dimpled fins promote flow mixing within the tube and the establishment of a thermal boundary layer. At a 135 degrees attack angle (EDT 1), the 1.0% Al2O3/DW nanofluid is found to be the best-performing nanofluid in the dimpled tube, improving Nu by up to 44.56%. Furthermore, ff presented an increase of 29.18% when comparing ST and EDT 1 flowing 1.0% Al2O3/DW at Re = 2000, while total S-gen is diminished by 37.75% in the same conditions.
An Image Fusion Method of SAR and Optical Images, Based on Image Intensity Fields, by Reducing the Effect of Speckle Noise
(Budapest Tech, 2024) Gencay, Semih; Ozcan, Caner
This study proposes an improved fusion method, that takes advantage of the combined strengths of existing fusion methods. First, current methods are compared using a fusion of noisy images from the Synthetic Aperture Radar (SAR) database, with optical images acquired at the same location and time. The obtained image and metric results showed that combining optical images with de-noised SAR provides better performance. Experiments have also shown that removing noise in SAR data causes the loss of important data in images. The proposed method divides the image into small patches in the noise removal phase. By calculating the standard deviation of these sub-patches, a different noise reduction ratio is applied for each region, thus preventing the loss of important detail features in the image. The proposed method has been compared with fusion methods recognized in the existing literature. Experimental results demonstrate that the proposed method, performs better than current fusion methods. The proposed method also yields better metric results, over other methods and it also eliminates the noise problems, often present in the images.
Sex Prediction of Hyoid Bone from Computed Tomography Images Using the DenseNet121 Deep Learning Model
(Soc Chilena Anatomia, 2024) Bakici, Rukiye Sumeyye; Cakmak, Muhammet; Oner, Zulal; Oner, Serkan
The study aims to demonstrate the success of deep learning methods in sex prediction using hyoid bone. The images of people aged 15-94 years who underwent neck Computed Tomography (CT) were retrospectively scanned in the study. The neck CT images of the individuals were cleaned using the RadiAnt DICOM Viewer (version 2023.1) program, leaving only the hyoid bone. A total of 7 images in the anterior, posterior, superior, inferior, right, left, and right-anterior-upward directions were obtained from a patient's cut hyoid bone image. 2170 images were obtained from 310 hyoid bones of males, and 1820 images from 260 hyoid bones of females. 3990 images were completed to 5000 images by data enrichment. The dataset was divided into 80 % for training, 10 % for testing, and another 10 % for validation. It was compared with deep learning models DenseNet121, ResNet152, and VGG19. An accuracy rate of 87 % was achieved in the ResNet152 model and 80.2 % in the VGG19 model. The highest rate among the classified models was 89 % in the DenseNet121 model. This model had a specificity of 0.87, a sensitivity of 0.90, an F1 score of 0.89 in women, a specificity of 0.90, a sensitivity of 0.87, and an F1 score of 0.88 in men. It was observed that sex could be predicted from the hyoid bone using deep learning methods DenseNet121, ResNet152, and VGG19. Thus, a method that had not been tried on this bone before was used. This study also brings us one step closer to strengthening and perfecting the use of technologies, which will reduce the subjectivity of the methods and support the expert in the decision-making process of sex prediction.
Evaluation of Hand Morphometry in Healthy Young Individuals from Different Countries
(Soc Chilena Anatomia, 2024) Sahin, Necati Emre; Bakici, Rukiye Sumeyye; Toy, Seyma; Oner, Zulal
This study aims to examine the hand morphometry of healthy young individuals from different countries and investigate the differences between countries in typing of hand based on the morphometric values obtained. In the study, 16 different parameters, including two surface areas and 14 lengths, were measured from the right hand of 579 volunteers (250 females, 329 males) from 7 different countries (Turkey, Chad, Morocco, Gabon, Kazakhstan, Senegal and Syria). Factor analysis was performed on the parameters, cluster analysis was performed according to the factor score obtained, and the hand types in the study were determined. As a result of the study, four different hand types were defined, and the distribution of these types according to countries was analyzed. All parameters showed significant differences between countries in both genders (p<0.05). According to the results of the study, there was a difference between male and female hand types between countries. In females, the type 1 hand type was found only in Gabon, the type 2 hand type was found only in Senegal, the type 3 hand type was found in Turkey, Morocco and Kazakhstan, while the type 4 hand type was significantly distributed in Senegal and Gabon (X-2 =104.62; df=18, p<0.05). In males, type 1 hand type was found in Turkey, type 2 hand type in Senegal and Gabon, type 3 hand type in Turkey, while type 4 hand type was significantly distributed in Morocco and Kazakhstan (X-2 =76.964; df=18, p<0.05).
Presence of Antibiotic Resistance Genes in Staphylococci Isolated From Bovine Subclinical Mastitis
(Sivar-Soc Italiana Veterinari Animali Reddito, 2024) Cantekin, Zafer; Ozmen, Gamze Ozge; Demir, Melek; Er, Zeynep Yilmaz; Gurturk, Kemal; Solmaz, Hasan; Ekin, Ismail Hakki
The prevalence of antibiotic resistance increases rapidly worldwide, and the primary culprit is represented by their widespread use. Subclinical mastitis is the leading cause of most antibiotic treatment, representing also one of the significant problems of bovine herd management. One of the main causes of subclinical mastitis is Staphylococcus aureus. Therefore, the determination of antibiotic resistance against Staphylococcus aureus is an essential step in the treatment of subclinical mastitis. The aim of this study was to identify antibiotic resistance genes in staphylococci obtained from cases of bovine subclinical mastitis in three provinces and the relationship between antibiotic resistance and ease of antibiotic availability (Burdur, Hatay and Van) in Turkey. In total, 283 isolates (Burdur, n = 36; Hatay, n = 47; Van, n = 200 isolates) were studied. The isolates were first identified as Staphylococcus aureus and/or non-aureus staphylococci (NAS) by conventional phenotypic methods, and the species was then confirmed by a multiplex polymerase chain reaction (PCR). A simplex PCR assay was performed to detect antibiotic resistance genes (mecA, mecC, aacA-aphD, ermA, ermB, ermC, tetK, tetM and blaZ). Among the isolates from all three provinces, the blaZ gene was the most prevalent antibiotic resistance gene, present in 43 out of 156 (28%) NAS isolates, 27 out of 127 (21%) S. aureus isolates and 25% of all the isolates. In contrast, tetM was the most prevalent gene in the Hatay isolates, detected in 64% of all isolates. The mecA-gene was present in 10% of the NAS, and in 3% of the S. aureus isolates. The mecC and ermA genes were not detected in any of the isolates. This shows that antimicrobial resistance, as determined by PCR, is common in Staphylococcus isolates from mastitis in Turkey, and warrants systematic treatment protocols as well as the implementation of preventative strategies to reduce antimicrobial usage.
A COMPREHENSIVE REVIEW OF LIFE CYCLE ASSESSMENT AND ENERGY EFFICIENCY IN 3D PRINTING FOR CONSTRUCTION: CURRENT STATE, BENEFITS, LIMITATIONS, AND FUTURE OUTLOOK
(College Publishing, 2024) Top, Semahat Merve; Cudzik, Jan; Ilerisoy, Zeynep Yesim
The agenda of Industry 4.0 strongly affects design and construction at all its phases, and three-Dimensional Printing (3DP) is an essential part of it. The emerging technology has the potential to become a more valid and accepted form of construction. This research is based on a literature review regarding the relationships between the concepts of Life Cycle Assessment (LCA) and energy efficiency for 3DP in construction research to understand the developments. Systematic bibliometric and scientometric analyses are used as data analysis techniques to make a detailed comparison. The comparison allowed for assessing and determining the current state, benefits, limitations, and future outlook. Current research is based on insights examining materials first (80%), followed by walls (15%), buildings (11%), and 3DP technology (6%). The findings highlight that 3DP technology offers significant advantages in terms of time efficiency, reliability, ecological impact, and sustainability within the construction industry. However, several challenges, such as the complexity of material mixture content design, the lack of standardized 3DP materials and codes, and the limited availability of experts in the field, prevent its widespread adoption. Further advancement of 3DP requires the development of standards, policies, training and materials for its full implementation in the construction industry.
Morphometry of the Middle Cerebral Arteries: A Radio-Anatomical Study Based on Computed Tomography Angiography Findings
(Soc Chilena Anatomia, 2023) Ciftci, Rukiye; Toy, Seyma; Ulubaba, Hilal Er; Senol, Deniz; Cinarli, FS.; Sigirci, Ahmet
Middle cerebral artery (MCA), which has the largest irrigation area of the arteries that feed the brain, is an important artery whose microanatomy should be well known because of its vascular variation. In pathologies which are known to affect the cerebrovascular system such as type 2 diabetes mellitus (T2DM) and hypertension, morphometric characteristics of MCA gain importance. The aim of this study is to compare the morphometric characteristics of M1 segment of MCA in T2DM and hypertensive patients with those of healthy control group by using computed tomographic angiography (CTA). The study was carried out with retrospective morphometric analysis of CTA images of 200 individuals between 40 and 65 years of age. The individuals were grouped in four as hypertensive patients (group 1), patients with T2DM (group 2), patients with hypertension and T2DM (group 3) and healthy control group (group 4). Length and diameter measurements of M1 segment were performed and recorded by using 3D CTA images. While statistically significant difference was found between bilateral M1 segment diameters of both women and men (p<0.05), no statistically significant difference was found between segment lengths (p>0.05). As a result of the post hoc analysis performed, it was concluded that right and left M1 segment diameter of group 1, group 2 and group 3 was found to be different from group 4 in both sexes (p<0.05). We believe that this study will both be a guide in radio-anatomic assessments to be performed and also increase microanatomic level of information in the surgical treatment of the artery by showing the morphometric changes that occur in M1 segment of MCA in T2DM diseases.
Cybersecurity Attack Detection Model, Using Machine Learning Techniques
(Budapest Tech, 2023) Avci, Isa; Koca, Murat
Millions of people use the web every day, in this age of technology and the internet. Protecting the privacy and security of these users is a significant challenge for cybersecurity developers. With tremendous technological advancements, there is a noticeable improvement in the cyber-attackers' capabilities. At the same time, traditional Intrusion Detection Systems (IDS) are no longer effective at detecting intrusions. After the tremendous competences achieved by Artificial Intelligence (AI) techniques in all fields, great interest has developed in its use in the field of cybersecurity. There have been many studies that use Machine Learning (ML)-based intrusion detection systems. Despite the strong performance of ML techniques in detecting malicious activities, some challenges still reduce accuracy of performance. Knowing the proper technique, as well as knowing the features, is essential for effective intrusion detection. Therefore, this study proposes an effective network intrusion detection system based on ML and feature selection techniques. The performance of four ML techniques, the Random Forest (RF), K-Nearest Neighbors (KNN), Support Vector Machine (SVM) and the Decision Tree (DT) systems for intrusion detection are explored. In addition, feature selection techniques are employed for the selection of important features. Among the techniques used, the RF technique achieved the best performance, outperforming other techniques, with an accuracy of 99.72%. This study elaborates on the detection of malicious and benign cyber-attacks, with a new-level, high accuracy.
DETERMINING FACTORS AND IT ADOPTION BY AUDITING LIMITED LIABILITY PARTNERSHIPS: MEDIATING EFFECT OF IT CONFIDENCE
(Iium Press, 2023) Thottoli, Mohammed Muneerali; Ahmed, Essia Ries
This research study examines the effect of information technology (IT) determining factors (IT awareness and IT proficiency) and IT adoption by auditing Limited Liability Partnerships (LLPs). This study also examines the mediating effect of IT confidence on the link between the determining factors and IT adoption by auditing LLPs. Data were gathered from 143 partners who are practicing chartered accountants registered as LLPs located in Kerala, India. The conceptual model is tested using structural equation modeling based on partial least squares. The findings confirm the direct effect of IT awareness, IT confidence on IT adoption as well as the mediating effects of IT confidence on the relationship between IT proficiency and IT adoption by auditing LLPs. The research study is performed only in the Indian LLPs perspective and future studies can be performed in other nations as well to generalize the findings. The findings of this research study can be used to guide practicing chartered accountants registered as LLPs, governing bodies of practicing auditors, and software developers while expanding the IT adoption by auditing LLPs. The determining factors of IT adoption have great potential for auditors of practicing firms for transforming from manual audits by adopting IT-enabled auditing tools to facilitate their audit services. The present research study gives valuable insight into the critical mediating role of IT proficiency and other IT variables as activating factors that impact auditing practice efficiency of auditing LLPs.
A novel proportional index to differentiate between demographically and clinically matched cases with papillary thyroid carcinoma or non-cancerous nodule: PLR-to-PDW ratio
(E-Century Publishing Corp, 2023) Deniz, Muzaffer Serdar
Objectives: To analyze PLR-to-PDW ratio as a novel diagnostic index in the discrimination of benign thyroid nodules (BTN) and papillary thyroid carcinoma (PTC), and to analyze the discriminatory power of a novel index (platelet-to-lymphocyte ratio divided by platelet distribution width: PLR-to-PDW ratio) in comparison with previously-examined inflammatory indices including neutrophil-to-lymphocyte ratio (NLR), PLR, prognostic nutritional index (PNI), systemic inflammation index (SII), and systemic inflammatory response index (SIRI). Methods: This cross-sectional retrospective research included 459 demographically and clinically-matched participants who underwent thyroid examination with ultrasonography and fine-needle aspiration biopsy. NLR, PLR, SII, SIRI and PLR-to-PDW were calculated manually from complete blood count results. PNI was calculated as albumin (g/dL) + 5 x lymphocyte count. Results: Among the inflammatory indices, NLR, PLR and PLR-to-PDW ratio were significantly higher in patients with PTC compared to those with BTN. Logistic regression showed that NLR (OR: 1.414, P=0.0083), PLR (OR: 1.537, P=0.0065) and PLR-to-PDW (OR: 2.054, P=0.0016) were independently associated with a greater likelihood of PTC. Among the previously-examined indices, PLR had the best discriminatory performance with 73.4% sensitivity and 70.8% specificity for a > 149.6 cut-off (AUC: 0.786, P=0.0011). However, the novel ratio examined in this study, PLRto-PDW, had better predictive value to distinguish PTC cases from BTN with 78.1% sensitivity and 73.7% specificity at a > 9.11 cut-off (AUC: 0.827, P=0.0001). Conclusions: The presently proposed PLR-to-PDW ratio exhibited the highest diagnostic discriminatory power compared to other inflammatory indices, indicating a relatively better utility to distinguish cases with PTC from those with BTN.
A Qualitative Research on the Cooperation-Based Development of Tourism in the Turkic World Countries
(Ahmet Yesevi Univ, 2022) Tuna, Muharrem; Ozyurt, Basak; Dugler, Aye Selin; Turkmen, Fatih; Uyamk, Necmi
The main purpose of the study is to determine the existing tourism potential of Azerbaijan, Kazakhstan, Kyrgyzstan, Cyprus, Turkey and Uzbekistan and to underline the importance of cooperation in the field of tourism. In this study, criteria sampling method and maximum diversity sampling method, which are among the purposeful sampling methods, were used in determining the sample. In addition, a case study, one of the qualitative research designs, was used. In the study, after in-depth interviews were conducted with 31 people from six different Turkish states, including tourism academics, ministry representatives and managers working in the tourism sector, thematic analysis was conducted using the MAXQDA 2020 qualitative data analysis program. As a result of the study, it was stated that cooperation in the field of tourism will contribute to the development of economies and the maintenance of political unity in Turkish states. Furthermore, it was realized that the tourism destinations in these countries should be promoted and marketed in various ways and an umbrella organization for tourism cooperation needs to be established.
MICROGRID ENERGY MANAGEMENT WITH DAY AHEAD AND NOVEL EGWO SOLUTION
(Taylors Univ Sdn Bhd, 2023) Talab, Odia; Avci, Isa; AL Sultan, Muhamed
Microgrids have emerged as a viable option for enhancing energy dissemination infrastructures' effectiveness, dependability, and eco-friendliness, garnering considerable interest. The optimal utilization of resources and cost reduction are critical factors in microgrid energy management. The present research introduces the Enhanced Gray Wolf Optimization (EGWO) algorithm, which aims to optimize energy management in microgrids subject to uncertain load demands and renewable energy sources. The EGWO algorithm endeavors to reduce total energy expenditure while guaranteeing a dependable and enduring power provision. The utilization of the day ahead strategy is implemented using deep learning techniques to forecast the load demand and generation within the microgrid. Subsequently, the EGWO algorithm is employed to optimize the scheduling of the various components of the microgrid, encompassing renewable energy sources and storage devices, to attain the minimum energy cost amidst conditions of uncertainty. The efficacy and efficiency of the EGWO algorithm in enhancing the energy management of microgrids is demonstrated through a comparative analysis with other optimization algorithms. This research's findings indicate that the enhanced grey wolf optimization algorithm approach yields a significant reduction in operational expenses of up to 7.5%. The implementation of energy management is facilitated by utilizing the EGWO algorithm, which yields a final cost of 841.755 ct/kWh. Obtaining 11% of the electricity from the primary power network was imperative to satisfy the required power load. The cost associated with the referenced power amounted to a nominal 5%, indicating a comparatively modest expenditure.
ENHANCED FAULT DETECTION AND CLASSIFICATION IN TRANSMISSION LINES USING FINE-TUNED LSTM MODEL AND DBN TRANSFORM-BASED FEATURE SELECTION
(Taylors Univ Sdn Bhd, 2023) Al Sultan, Muhamed; Avci, Isa; Talab, Odia
Fault detection and classification in transmission lines is an important problem in power system protection. This paper proposes a novel fault detection and classification approach based on the fine-tuned LSTM model and dbN wavelet transform. Specifically, the selection of the optimal decomposition scale is proposed. An improved Arithmetic Optimisation Algorithm (IAOA) to enhance the accuracy of the LSTM model by optimizing its hyperparameters and reducing model (RMSE) error is implemented. The proposed method makes a significant advancement in the field of fault detection and classification. A simulated version of the model is run through MATLAB using the Three-Phase Series compensation network (735kV, 60 Hz, and 300 km of fault distance) to classify faults. Features are extracted to a depth of three using the dbN, which is modelled as a wavelet function in this investigation. Finally, the IAOA-LSTM model achieves 99.99% accuracy and 0.0010 loss when testing 2545 simulated samples with five different fault types. Maintaining the stability and reliability of power systems relies heavily on fault detection and classification, which is aided greatly by the proposed method. Implementing the IAOA algorithm for hyperparameter optimization and model error reduction has also been shown to enhance the accuracy of the LSTM model further. Therefore, the proposed approach can significantly contribute to developing more advanced and efficient protection systems for power transmission lines.
Parameter estimation of the wind speed distribution model by dragonfly algorithm
(Gazi Univ, Fac Engineering Architecture, 2023) Kose, Bayram; Aygun, Hilmi; Pak, Semih
Purpose: In modelling wind speed by Weibull probability distribution function (Wpdf) for potential calculation of wind energy and wind speed characterization, the purpose of the study is to estimate the distribution parameters.Theory and Methods: The performance of the proposed method has been evaluated by comparing not only the classical methods which are the moment method (MM) and the least squares method (LSM) but also metaheuristic optimization algorithms which are Dragonfly Algorithm (DA), Genetic Algorithm (GA) and Particle Swarm Optimization (PSO). Determination coefficient (R2) and root mean square error (RMSE) were used to evaluate the performance of these parameter estimation methods. Results: Dat obtaine from 6 measurement stations were used in the study. The results show that while the DA method gives the best performance according to the determination coefficient (R2) criterion in all stations, it provides the best performance in 2 stations according to the root mean square error (RMSE) criterion. In addition, it was observed that the DA method showed better performance in all stations compared to the LSM method.Conclusion: It is seen that the proposed DA algorithm for wind energy potential calculation can be used to estimate Weibull and two-component mixed Weibull distribution parameters.
Investigation of Obtaining Natural Humic Acid From Asphaltites Commonly Found in Sirnak-Uludere Region
(Gazi Univ, 2022) Taskesen, Edip; Acar, Sukru; Arli, Fatih; Dumrul, Hakan; Ertugrul, Gorkem; Bulbul, Saban; Ozcan, Emine
The physical and chemical properties of asphaltites found in significant amounts in Sirnak and its surroundings are close to coal. But it differs from coal because of its formation sources and chemical processes. Asphaltites were separated from the oil in liquid state by tectonism and settled in other locations, hardened by chemical reactions during geological processes and turned into solid phase. Most of the heating need in the Southeastern Anatolia Region is met by asphaltites. However, it is a raw material with low calorific value, high content of ash, sulfur and moisture, and high potential to adversely affect air pollution.It contains nitrogen and humic acid that dissolves slowly in aqueous media and can be used as soil reinforcement. In this study, researches were made to obtain natural humic acid from the content of asphaltite samples taken from the mine reserve in Uludere district. In the experiments made with samples, the effects of pH changes, temperature changes, changes in mixing times, precipitation in KOH and HCl solution were investigated towards optimal humic acid recovery efficiency. Accordingly, natural humic acid was obtained with the highest efficiency of 33.95% as a result of the studies conducted with temperature experiments from the sample of the Uludere region.
NUMERICAL ANALYSIS OF THE STEAM TURBINE PERFORMANCE IN POWER STATION WITH A LOW POWER CYCLE
(Taylors Univ Sdn Bhd, 2023) Bdaiwi, Mothana; Akroot, Abdulrazzak; Wahhab, Hasanain A. Abdul; Mahariq, Ibrahim
In this paper, an analysis of the temperature and quantity balance of the thermal power plant for the Al-Dura (K-160-13.34-0.0068) station was first studied and used for reference. This work describes a possible way to build a simulation model of the most important parts of power plant Al-Dura (K-160-13.34-0.0068). The Cycle-Tempo and MATLAB/Simulink packages are used to model the energetic and exergetic analysis of the power plant. MATLAB/Simulink software was used to simulate the behaviour of a Steam turbine with high-pressure, intermediate-pressure, and low-pressure steam, with a load response in a stable circumstance over a range of 50% to 100%. The model is based on Stodol's law and simulates the pressure and enthalpy alongside the dissimilar turbine phases and the vapor and water extraction. The effect of the vapor and water extraction on the turbine is also elucidated. Areas of essential energy loss and exergy decimation will be resolved. The impact of changing the power plant load on the exergy analysis is determined. The response of suggested purposes to estimate these vapor properties is compared with standard data and showed high accuracy (the modelling error is less than 0.01%).
NUMERICAL SIMULATION OF A POROUS MEDIA SOLAR COLLECTOR INTEGRATED WITH THERMAL ENERGY STORAGE SYSTEM
(Taylors Univ Sdn Bhd, 2023) Nawaf, Mohammed Y.; Akroot, Abdulrazzak; Wahhab, Hasanain A. Abdul
Increasing the contact area between the working fluid and solid surface is proven to be a successful technique for enhanced heat transfer. This paper presents computational simulation results of a closed active solar water heating system. The system is a novel solar water heating as it is compacted with a heat transfer unit filled with an open cell foam porous media for increased heat transfer area and molten salts of 60% sodium nitrate and 40% potassium nitrate as phase change material. Water is circulated between the collector and a storage tank. The numerical simulation and analysis were performed using ANSYS FLUENT 17.0, assuming a steady, incompressible, and 3D state. The system performance was tested using two flow rates of the circulating water of 2.5 and 3.5 l/min. Numerical results showed that the temperature difference between the inlet and outlet decreases with increasing water flow rates through the solar water heater. The temperature difference decreased by 11.5% when the flow rate increased from 2.5 to 3.5 l/min. Also, the results showed a good prediction of the real flow behaviour inside the thermal energy storage. Also, the evolution of the numerical simulation accuracy for porous media solar collector analysis is still a topic of future research.
EXPERIMENTAL COMPARISON OF ECO-FRIENDLY REFRIGERANT COUPLES R407C/R32/R600a (90/10 BY WT.%) AND R407C/R32 TO REVEAL THE GWP AND THERMODYNAMIC PROPERTIES
(Begell House Inc, 2023) Al Kraim, Adel Mohmed; Atas, Safak
In this experimental study, based on cooling couples a new mixture (90%R32 + 10%R600a) has been proven to be better than R32 for the global warming potential (GWP) in a low-pressure cycle (LPC), within a high-pressure cycle (HPC) R407C by utilizing a small laboratory cooling system. This system consists of two cooling cycles connected by a heat exchanger and has also been termed as a mini cascade refrigeration system (MCRS). The main aim of this study is to study a suitable gas or mixture for MCRS at the lowest GWP value and a low-temperature cooling room to reach less than -30?. In the same way, the following conditions have been determined in this research: the inlet and outlet temperatures of the evaporator, condenser, heat exchanger, compressors, with evaporator pressure as well as superheat. Consequently, MCRS can be used with thermostats at the lowest degree of -32? or less, the mixture has results close to R32 and the coefficient of performance for MCRS COPMCRS is equal to 1.63 and 1.78 for the new mixture and R32, respectively, under the same operating conditions. Therefore, the ozone depletion potentials (ODP) for R32 and the new mixture are equal to zero, and the GWP for the new mixture is less by amount of 63 than that for R32. The MCRS can be used in a small place, for instance, transport blood samples, blood tests, and vaccines by small cars. Both R32 and R600a are flammable gases, so this study will be carried on in the future for safer replacements.

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