Advanced Engineering Science

Performance analysis and kinematic test of the BeiDou Navigation Satellite System (BDS) over coastal waters of Türkiye

Volkan Akgül — 2024-02-09

Global Navigation Satellite System (GNSS) is essential for current civilization because it is used in many areas such as transportation, construction, agriculture, meteorology, disaster monitoring, risk management, etc. Therefore, developed countries strive to establish their positioning service to use the benefits they provide. BeiDou Navigation Satellite System (BDS) is a positioning service developed by China that recently achieved global coverage. Like other GNSS, BDS is subjected to various tests before commissioning. The system's control is the same as other positioning services, and it is tracked by ground control stations. In this context, position dilution of precision (PDOP), pseudorange multipath, and carrier phase signal-to-noise ratio (SNR) performance analysis were carried out with 30 seconds interval BDS data of ZBEU (Zonguldak Bulent Ecevit University) GNSS monitor station. BDS's multipath and SNR results were compared with other global positioning services. Single and multi-system precise point positioning (PPP) solutions were examined comparatively using the 2019 and 2023 data of the ZBEU station. In addition, BDS kinematic test results were examined with 1-second interval data of transects along the coast of the Black Sea and the Mediterranean Sea. Satellite visibility, PDOP, and positioning performance were analyzed along the offshore survey route. In terms of SNR and multipath, the results showed that the performance of BDS signals was similar to other GNSS. Depending on the satellite visibility change, SPP results in the Mediterranean were better than the Black Sea. It has been observed that BDS PPP results were improved from 2019 to 2023, and achieved almost the same results as other GNSS.

The impact of alternative fuel on diesel in reducing of pollution from vehicles

Asllan Hajderi — 2024-02-09

The main source of energy for vehicles is currently internal combustion engines. These engines emit the main pollutants carbon oxide, carbon dioxide, hydrocarbons, nitrogen oxides, and particles matters into the atmosphere. The biggest polluter of nitrogen oxides and particles are diesel engines. For this purpose, the addition of alternative fuels ethanol, methanol, biodiesel, and Fisher-Tropsch fuel to conventional diesel fuel in the amount of 5-15% has been studied, to see their impact on the reduction of carbon dioxide and pollution. For this, the analytical method of carbon dioxide calculation, experimental data from the literature and experimental measurements of the opacity coefficient were used. From the obtained results, it results that in reduction of CO₂ affect more the fuels B15 up to 11.5%, M-15 up to 9%, FT 15 up to 7.5% and E-15 up to 6%. Also, M 15 has the greatest impact on the reduction of particles and nitrogen oxides with a reduction of 45% and 30% respectively, followed by E 15 with 30% and 20% and B15 and FT15 with 30% and 25%. Experimental measurements of the opacity coefficient confirm that the use of M15 and E15 fuels reduces pollution by 35% and 25%.

Evaluation of the worn texture of the region 4 in Tabriz, Iran, with an emphasis on increasing populatability

Shiva Sattarzadeh Salehi — 2024-02-11

Today, due to the increase in population and the development of cities in areas where cities do not have enough land for development due to various reasons, such as natural obstacles, worn-out tissues are considered as urban potentials for development, which the ability to plan and provide land and the development of the city exists in these contexts. Therefore, these contexts need to be identified, planned and regulated by rules and laws and implementation. The purpose of the current research is to evaluate the worn-out texture of the 4th region of Tabriz with an emphasis on increasing population. The research method used is a descriptive-analytical method and the desired indicators of residential buildings analysis with GIS. The results of the research showed that in terms of the efficiency of building parts, they are in an unfavorable condition, and the criteria compiled for the modification of these structures will lead to an increase in the efficiency of buildings and residential parts compared to the situation before the intervention.

Circular economy in wood processing sector, challenges, opportunities and solutions

Ina Vejsiu — 2024-02-11

Economic circulation is a concept that is closely aligning with sustainability. For this reason, various stakeholders strive to collaborate in defining basic concepts, analyzing key issues, and directing solutions to these problems. In this study, we have attempted to address the challenges of the wood processing sector in Albania concerning the increase in the use of wooden products and the potential export of these products. During the last years, the concept of the circular economy has taken an important role in the literature, as well as in the production sector all over the world. Saying this, in Albania we are facing the same problem. The concept of the circular economy in our country was introduced lately. The companies that operate in the wood processing sector must step forward from a linear economy to a circular one as soon as possible. This material presents some information collected based on interviews conducted with some of the wood processing companies in Albania. For this study we prepared a closed answer questionnaire in order to have a simple analysis of the results gathered. As a result of this interview, skills and competencies supporting the transformation to circular business models were presented. The companies need some innovative design idea for the reuse of their basic products.

Levels of BTEX and Chlorobenzenes in water samples of White Drin River, Kosovo

Aferdita Camaj — 2024-02-12

In this paper, the concentrations of some volatile organic compounds (VOC) in water samples from the White Drin River (Kosovo) are presented. The White Drin River is one of the largest river in Kosovo and one of the largest in the Balkans. Water of the river could be affected by anthropogenic pollutions that comes mainly by directly discharges of urban wastewaters. The volatile organic pollutants that were analyzed were chlorobenzenes (mono-, di-, tri-, tetra-, penta- and hexachlorobenzene) and BTEX (Benzene, Toluene, Ethylbenzene, ortho-, meta- and para-Xylenes). Water samples were taken in February 2023, at 15 different stations from Drini Waterfall (near Peja to Albanian border). The head space solid phase micro-extraction (HS/SPME) method was used for the extraction and quantitative analysis of chlorobenzenes and BTEX followed by gas chromatography (GC) techniques. This method presents advantages for the analysis of volatile pollutants because it eliminates the use of organic solvents and different sample treatment steps that often lead to erroneous results. The sensitivity and reproducibility of HS is favorable for volatile organic pollutants. The adsorption of organic pollutants was carried out on a polydimethylsiloxane (PS) fiber at a temperature of 50^oC for 30 minutes. Desorption process was carried out in the injector of the gas chromatograph at high temperature (250 °C for 10 seconds). The qualitative and quantitative analysis of chlorobenzenes (mono-, di-, three-, tetra-, penta- and hexachlorobenzene) was realized in the GC/ECD apparatus, while the analysis of BTEX was carried out in the GC/FID apparatus. VOC were present almost in all analyzed samples. BTEX presence is related to the high intensity of transport near the river. The presence of chlorobenzenes can be a consequence of urban spills, of cleaning/sanitization processes, as degradation products of other compounds (pesticides, PCBs, etc).

Helmholtz equations and their applications in solving physical problems

Davron Aslonqulovich Juraev — 2024-02-20

The Helmholtz equation is a well-known concept in the field of physics, particularly when studying problems involving partial differential equations (PDEs) in both space and time. It is a time-independent form of the wave equation and is derived using the method of separation of variables to simplify the analysis. In this research article, we explore the Helmholtz equation and delve into its physical significance. The Helmholtz equation plays a crucial role in solving various physics problems, such as seismology, electromagnetic radiation, and acoustics. It encompasses a wide range of scenarios encountered in electromagnetics and acoustics and is equivalent to the wave equation under the assumption of a single frequency. In the context of water waves, it emerges when the dependence on depth is removed. This often leads to a transition from the study of water waves to more general scattering problems. By employing a cylindrical eigenfunction expansion, we observe that the modes related to the Helmholtz equation decay rapidly as distance approaches infinity. This property enables us to derive asymptotic results in linear water waves based on findings in acoustic or electromagnetic scattering.

Optimal design, cost analysis and impact of a tracked bifacial PV plant in distribution system

Andi Hida — 2024-03-01

The rapid development in the photovoltaic (PV) sector requires more and more in-depth studies. In this context, this paper presents a techno-economic analysis of a 10 MWp PV plant installed in the south-west of Albania. To increase its performance, a single-axis solar tracking system with bifacial modules has been chosen. Moreover, the optimal design and sizing of the PV plant is determined through software, considering various factors. In this context, the results show that the annual yield of the on-grid PV system will be 1,670 kWh/kWp. In the same vein, the calculations present that the internal rate of return IRR is 20.6%, which indicates that the project will have a positive return on the investment value. Meanwhile the payback period of the investment is 4.8 years, which is considered as an investment that provides high income. These values are quite attractive for investors. On the other hand, the impact of this PV system on the distribution system parameters, for different scenarios, has been studied. While an improvement is seen in the voltage levels of the nodes, some of the lines and transformers show technical losses due to their loading.

Examination of buildings with different number of floors using non-linear time history analysis according to TBEC-2018 and EC 8 seismic codes

Mehmet Yılmaz — 2024-04-14

Earthquakes are among the natural disasters that occur on earth and cause loss of life and property. As a result of the earthquakes that have occurred on the earth from the past to the present, the issue of earthquake performance of structures has come to the fore in structural and earthquake engineering. Within the scope of this research, the carrier system; Consisting of a unhollow reinforced concrete shear wall frame system with high ductility having the same floor formwork plan; The seismic performance evaluation of 10, 15 and 20 storey existing reinforced concrete buildings was made by using nonlinear time history analysis according to Turkish Building Earthquake Code 2018 (TBEC-2018) and Eurocode 8 (EC 8) earthquake codes. Within the scope of the study, SAP200 (v25) computer software was used for modelling of the structures and performance analysis. In scope of the data obtained, it has been determined that TBEC-2018 is on the safer side compared to Eurocode 8.

Approximation of surface urban heat island (SUHI) effect over four populated cities of Andhra Pradesh state of India using ground and satellite data

Jagadish Kumar Mogaraju — 2024-08-20

This work reports the probable effect of population ingress in generating urban heat islands over four cities of Andhra Pradesh state of India. We identified twenty-six UHIs and chose four UHIs based on the population data. The period from 1961 to 1990 was selected as the reference period, and 2003 to 2020 was selected as the study period to determine the deviations in mean temperatures. We framed a methodology to filter and select the UHIs to know the effect of SUHI using online resources for data and plots that are free of cost and user-friendly. One out of four UHIs exhibited a stronger deviation in night-time temperatures than in day-time temperatures. We observed that the rise in population equally contributes to the temperature deviations over the long term in the selected areas. We conclude that the population ingress may influence land surface temperatures and induce the SUHI effect.

Leveraging SVD for efficient image compression and robust digital watermarking

Ornela Gordani — 2024-09-03

In terms of digital files, compression is the act of encoding information using fewer bits than what’s found in the original file. When we say image compression, we have in mind an image that has fewer bytes than the original image but has the most important features that describe the original image. So, the aim of image compression is to reduce the image size without degrading image quality below an acceptable threshold. In MATLAB, an image is stored as a matrix. One approach is to apply the Singular Values Decomposition (SVD) to the image matrix. This method is implemented in MATLAB. In order to divide the matrix of the given image into three other matrices in MATLAB, we can use the function svd(). As performance metrics, we can use PSNR and Compression ratio. Digital Watermarking is defined as the process of hiding a piece of digital data in the cover data which is to be protected and extracted later for ownership verification. In an SVD-based watermarking scheme, the singular values of the cover image are modified to embed the watermark data. All tests and experiments are performed using MATLAB as the computing environment and programming language. Also, in the RStudio programming language we can see the implementation of the SVD method in image compression.

Investigation of the effect of Isparta pumice on the unconfined compressive strength and swelling pressure of clay

Ömür Çimen — 2024-09-03

This study investigates the effect of pumice, known as Karakaya pumice, and taken from the Isparta-Gölcük region, on clay’s unconfined compressive strength and swelling pressure. For this purpose, the physical and index properties of the clay and pumice were determined and then 10%, 15%, 20%, 30%, 40%, and 50% pumice by weight were mixed with clay. Standard compaction tests were performed on clay, pumice, and clay-pumice mixture. With these experiments, the effect of pumice on compaction parameters was evaluated. Samples were prepared under optimum water content and maximum dry unit weight conditions to conduct unconfined compressive strength and swelling tests. The results show that as the pumice additive ratio increased up to 30%, the unconfined compressive strength also increased. However, it was observed that when the additive ratio exceeded 30%, the unconfined compressive strength decreased. The results of the swelling pressure test indicate that as the amount of pumice in the mixture increases, the swelling pressure decreases. It has been determined that Isparta pumice can effectively stabilize compacted clay, reducing its swelling pressure and increasing its unconfined compressive strength. The recommended rate for adding pumice to the clay is 30%.

Influence of antimony doping on structural, morphological and optical properties of CuO powders

Saadet Yıldırımcan — 2024-09-04

In this study, pure and antimony (Sb) doped CuO nano and micro powders were produced by chemical bath deposition (CBD) technique. Their structural, morphological, elemental and optical properties were examined using XRD, SEM, EDX and UV-Vis techniques. According to crystallographic structure analysis, the pure and Sb doped CuO powders were obtained in monoclinic phase. The crystallite size of the powders decreased with the Sb concentration. The FE-SEM images clearly show that flower-like structures in both pure and Sb doped CuO powders were grown. Moreover, the EDX spectra show that the peak intensity of Sb increases upon increasing doping concentration of Sb. The band gap energy value of the powders increased from 1.58 eV to 1.95 eV with increased Sb concentration in CuO. In addition, the key optical parameters such as refractive index, extinction coefficient, and both real and imaginary parts of the dielectric constant were calculated.

Learning transformation and virtual interaction through ChatGPT in Albanian higher education

Besjana Mema — 2024-09-05

The integration of artificial intelligence (AI) in education has brought about significant improvements in the efficiency of the educational process, global learning promotion, personalized learning experiences, intelligent content creation, and the optimization of educational management. AI, as a technology, holds great potential in education, particularly in fostering personalized learning tailored to the individual needs and interests of each student. However, the implementation of AI in education presents challenges and ethical considerations, such as data privacy, equitable access to education, and the evolving role of educators. Striking a balance between technology and the essential role of educators is crucial to ensure a focus on holistic student development and preparation for a changing world. Despite the recent introduction of ChatGPT, there is a lack of systematic reviews on its impact on education. Therefore, the main objective of this paper is to analyze existing situation on the use of ChatGPT in higher education in Albania, addressing questions about the state of scientific research, benefits and challenges of implementation, and future trends in the field. An online questionnaire will be proposed and distributed to obtain this information. The collected data will be elaborated on and analyzed. The study includes 311 students from both bachelor's and master's programs. Importantly, the questionnaire encompasses students from various Albanian universities, including both public and private institutions. Overall, the study contributes valuable insights into the impact and potential of ChatGPT in higher education, paving the way for informed decision-making and future research in this dynamic field.

The development of the Albanian wood industry and the correlation of the main strategic business factors

Alketa Grepcka — 2024-09-11

In Albania, numerous studies have been conducted on various business categories; however, there is limited or no evidence regarding strategic management within the wood industry. Over the years, this industry has undergone significant changes. Business owners report that their operations are continuously evolving, necessitating shifts in their operational models to: 1) improve efficiency, 2) reduce complexity, and 3) lower costs. The research was conducted in the Tirana and Durrës districts, with data collected from wood processing companies. A total of 30 questionnaires were processed, followed by statistical analysis. The study revealed the following findings: 1) In terms of product development, companies identified the creation of new products as a strong factor; 2) Operational management remains in its early stages, but its significance is well recognized; 3) Key areas of operations management are being implemented, though inventory management and innovation remain underdeveloped; 4) Although companies aspire to market leadership, they primarily follow customer demands, lacking innovation as a competitive advantage; 5) Regarding technology, 70% of companies cited the acquisition of new machinery as a crucial factor; 6) The generation of new product ideas faces obstacles, particularly in the financial sector and due to regional developments; 7)There is a strong correlation between improved customer service and quick response times in product distribution; 8) Companies have not yet achieved the level of synchronization necessary for optimal supply chain management; 9)Firms should focus on gathering feedback from both suppliers and customers to enhance their systems. This analysis highlights the need for greater innovation, technology investment, and operational management improvements in Albania's wood industry to remain competitive in an evolving market.