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.