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Item Power systems dynamic simulation developments for power quality monitoring:(GMIT, 2023-05-23) Ankhbayar Vandandorj; Supervisor 1st : Prof. Dr. Ariunbolor Pu.; Supervisor 2nd : Dr. Enkh-Amgalan B.This Master's thesis addresses the critical issue of high harmonics impacting the power grid system's power quality, resulting in financial losses, equipment heat generation, transmission and distribution line problems, and electrical shock to end-users. These harmonics are especially problematic within industrial environments such as steel melting furnaces, where significant voltage and current volatility are observed. This study utilized real-time data measurement at the highest and lowest potential points within these furnaces. It developed MATLAB's dynamic simulation to accurately represent and analyze the sinusoidal waveform of fundamental harmonics and the distinctive harmonics generated within the power system's energy conversion process. This analysis adheres to the specifications outlined in the MNS 1778:2007 and IEEE 519-2014 standards, contributing to understanding and preserving power quality in energy dynamics. The gathered data was imported into Microsoft Excel for further processing and evaluation. MATLAB's Graphical User Interface simulated the harmonic oscillations and changes under varying load conditions. The preliminary findings reveal that the odd harmonics, particularly those not divisible by three, are causing substantial damage to the fundamental harmonics waveform, significantly impacting the electrical grid system. Given the current lack of quality control or standardization in the MNS 1778:2007, it is crucial to integrate the IEEE 519-2014 standard's current quality control measures. Future research will delve into the differences in odd harmonics divided by three and not divided by three and develop strategies to filter them using a hybrid filtering system. Furthermore, the research anticipates implementing current harmonics or quality standards into the Mongolian electrical system, promoting electrical purity in the industrial and mining sectors.Item Design And Implementation Of A Data Acquisition System For Multi Fault Diagnosis Analysis In Induction Motors(GMIT, 2024-05-20) Tuvshin Gankhuyag; Supervisor 1: Prof. Dr. Ariunbolor P.; Supervisor 2: Prof. Dr. Turbat ShagdarThis Master's thesis focuses on the design of a data acquisition system for detecting motor faults early and implementing smart maintenance strategies. Understanding and diagnosing faults in induction motors is critical for maintaining the reliability and efficiency of industrial operations. The thesis aims to design a data acquisition system for the early detection of motor faults. By developing a novel data acquisition system and comparing its performance with existing systems, this research aims to provide valuable insights and practical solutions to enhance motor fault diagnosis, ultimately improving operational reliability and reducing downtime in industrial settings. The study begins by introducing the main research topic, discussing its broader context and significance, and emphasizing the need for a reliable data acquisition system for multi-fault diagnosis in induction motors, particularly squirrel cage motors widely used across various industries. A comprehensive study of key motor elements is provided, including their importance and operating principles. Existing methods for motor fault diagnosis and online condition monitoring are covered. The thesis introduces data acquisition systems and reviews various algorithms for their design, including sensors, signal processing techniques, and data analysis methods. The research delves deeper into data acquisition systems, reviewing various algorithms for their design, the selection and placement of sensors, signal processing techniques, and data analysis methods. It investigates the development of an algorithm, flow chart, and block diagram for a data acquisition system to study motor fault data from different load motors in the mineral processing plant. The study details the development and design of the data acquisition system, analyzes and compares the results obtained from different motor loads, and discusses essential aspects based on these results. Furthermore, this research discusses the development and evaluation of a newly designed data acquisition system, the "Motor Analyzer LEVEL V1.0." It compares it with existing systems in the industry, specifically the Baker EXP3000 Explorer Dynamic Motor Analyzer (99-EXP3000-CE). The Fast Fourier Transform (FFT) converts real-time data from the time domain into the frequency domain, facilitating detailed analysis. The "Motor Analyzer LEVEL V1.0" was developed based on this research and was tested against the Baker EXP3000 Explorer. Voltage measurements in the time domain from both systems showed very similar results. However, the horizontal axis scales differed due to variations in sampling rates—1000 Hz for the Motor Analyzer LEVEL V1.0 and 10000 Hz for the Baker EXP3000 Explorer. The frequency domain analysis also demonstrated substantial similarity between the two systems, with a validation accuracy of nearly 98% for both current and voltage measurements in both time and frequency domains. 6 This research marks the first development of the Motor Analyzer LEVEL V1.0 in Mongolia is contributing significantly to advancements in local industrial technology. The thesis summarizes these findings, presents conclusions, and offers further recommendations for future research to enhance industrial operations' reliability and efficiency.Item ASSESSMENT OF SOIL HEAVY METAL DISTRIBUTION IN NALAIKH DISTRICT, ULAANBAATAR, MONGOLIA(GMIT, 2022) Shinetsetseg Lkhagvasuren; Supervisor 1: Dr. Martin Knippertz; Supervisor 2: Prof. Dr. Gantuya GanbatThis research aims to assess the distribution and contamination levels of heavy metals (As, Cd, Cr, Cu, Ni, Pb, and Zn) in the soil of Nalaikh District, Ulaanbaatar, Mongolia. Soil samples were collected from various locations, including mining sites, residential areas, and along roadsides, and analyzed using X-Ray Fluorescence (XRF) spectrometry. The findings indicate that the concentrations of certain heavy metals exceed the natural background levels. The environmental quality was evaluated using the Geo-accumulation Index ($I_{geo}$) and the Contamination Factor (CF). The results suggest that mining activities, coal extraction, and urbanization are the primary contributors to soil contamination in the region. This study provides essential data for environmental monitoring and the development of soil remediation strategies in Nalaikh DistrictItem ON GAP FUNCTIONS FOR QUASI-EQUILIBRIUM PROBLEMS VIA DUALITY(Springer Nature, 2024-03-06) Lkhamsuren AltangerelWe extend gap functions to quasi-equilibrium problems by using the duality results. In particular, we obtain new results for quasi-equilibrium problems known earlier for equilibrium problems and mixed quasi-variational inequalities. Bibliography: 12 titles.Item Gap functions for quasi-variational inequalities via duality(Springer Nature, 2018-01-10) Altangerel, L.This paper deals with an application of duality theory in optimization to the construction of gap functions for quasi-variational inequalities. The same approach was investigated for variational inequalities and equilibrium problems in (Pac. J. Optim. 2(3): 667-678, 2006; Asia-Pac. J. Oper. Res. 24(3): 353-371, 2007), and the study shows that we can obtain some previous results for variational inequalities as special cases. Moreover, some applications dealing with the generalized Nash equilibrium problems and mixed variational inequalities are presented.Item Dividends and Compound Poisson-processes: A new Stochastic Stock Price Model(World Scientific, 2022-05-30) Battulga Gankhuu, Jacob Kleinow, Altangerel Lkhamsuren, Andreas HorschThis study introduces a stochastic multi-period dividend discount model (DDM) that includes (i) a compound nonhomogenous Poisson process for dividend growth and (ii) the probability of firm default. We obtain maximum likelihood (ML) estimators and confidence interval formulas of our model parameters. We apply the model to a set of firms from the S&P 500 index using historical dividend and price data over a 42-year period. Interestingly, stock price estimations calculated with the model are close to the observable prices. Overall, we prove that the model can be a useful tool for stock pricing.Item An Exact Penalty Approach and Conjugate Duality for Generalized Nash Equilibrium Problems with Coupling and Shared Constraints(Иркутского государственного университета, 2020-09-11) Altangerel, L. & Battur, G.Generalized Nash Equilibrium Problems (GNEP) have been attracted by many researchers in the field of game theory, operational research, engineering, economics as well as telecommunication in recent two decades. One of the most important classes of GNEP is a convex GNEP with jointly convex or shared constraints which has been studied extensively. It is considered to be one of the most challenging classes of problems in the field. Moreover, there is a gap in the studies on the GNEP with coupling and shared constraints. The aim of this paper is to investigate the relationship between an exact penalty approach and conjugate duality in convex optimization for the GNEP with coupling and shared constraints. In association with necessary optimality conditions, we obtained the parameterized variational inequality problems. This problem has provided an opportunity to solve many other GNEs. Some numerical results are also presented.Item ‟Assessment of Soil Erosion, Contamination, and Rehabilitation Potential in Mongolian Mining Regions: A Case Study in the Erdenet Copper and Molybdenum, and Baganuur Coal Mining Areas”(Von der Fakultät für Georessourcen und Materialtechnik der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2024-07-04) Enkhjargal Sodnomdarjaa, M.; Univ.-Prof. Dr. rer. nat. Frank Lehmkuhl; Prof. Dr. rer. nat. Daniel KartheMining plays a vital role in Mongolia’s economy, contributing significantly to export revenue. However, this economic benefit often comes at the cost of environmental degradation, particularly in regions surrounding major mining sites like the Baganuur lignite mine and the Erdenet copper-molybdenum mine. This study examines the long-term impacts of mining on soil erosion and contamination in Mongolia’s semi-arid steppe zones, aiming to provide insights into the extent of degradation and propose strategies for mitigation and rehabilitation. The study quantifies soil erosion rates in mining regions utilizing the Revised Universal Soil Loss Equation (RUSLE) model, remote sensing data, and ground truth observations spanning nearly three decades (1989-2018). Results show a clear correlation between rainfall erosivity and soil erosion, particularly noting peak erosion in July 2018 in both study areas, reaching 7.88 t ha-1month-1 in the Erdenet area and 9.46 t ha-1month-1 in the Baganuur area. Additionally, the spatial distribution of erosion underscores localized impacts near mining sites and adjacent industrial zones. In addition, erosion due to mining activities has led to soil contamination with Heavy Metals and Metalloids (HMM), posing ecological and health risks. Various indices, such as the Potential Ecological Risk Index (RI), Nemerow Integrated Pollution Index (PIN), and Geoaccumulation Index (Igeo), are used to assess soil contamination levels. Findings reveal elevated concentrations of elements such as Zn and As in the Baganuur mining area, and of Cu, Cr, and Zn in the Erdenet mining area. These concentrations exceed the Maximum Permissible Level (MPL) of Mongolian Soil quality standard (MNS 5850:2019), particularly in proximity to mining and industrial areas. This underscores the urgent need for soil rehabilitation initiatives to mitigate environmental and health hazards. Beyond soil degradation, mining activities have broader environmental and socioeconomic consequences. The study evaluates these impacts, emphasizing the importance of science-based rehabilitation plans and robust implementation of environmental regulations aligned with the United Nations Sustainable Development Goals (UN SDGs). Continuous environmental assessments and rehabilitation initiatives are supported to ensure the long-term sustainability of Mongolia’s mining sector, safeguarding both natural ecosystems and local communities. Based on the study findings, several recommendations emerge for mitigating soil degradation and promoting sustainable mining practices in Mongolia. These include:- Implementation of erosion control measures, such as vegetative cover and terracing, to reduce soil erosion rates in mining regions. - Adoption of soil remediation techniques, including phytoremediation and chemical stabilization, to address soil contamination and restore ecosystem health. - Strengthening of environmental regulations and enforcement mechanisms to ensure compliance with national standards and promote responsible mining practices. - Integration of environmental considerations into mine planning and operation processes, emphasizing the importance of continuous environmental impact assessments and monitoring. By comprehensively understanding the drivers and consequences of soil erosion and contamination, stakeholders such as mining companies, government agencies, local communities, and environmental organizations can collaboratively devise and implement effective mitigation and rehabilitation strategies. This concerted effort aims to ensure the long-term sustainability of Mongolia’s mining sector and the well-being of its inhabitants and wildlife, all while promoting sustainable development.Item NATURAL REHABILITATION POTENTIAL IN MINING AREAS(GMIT, 2023) Oyun-erdene Tsogtsaikhan; 1st Supervisor: Dr. Martin Knippertz; 2nd Supervisor: Prof. Ph.D. Gantuya GanbatItem DESIGN AND ANALYSIS OF A HYBRID RENEWABLE MICROGRID SYSTEM FOR MINE SITES IN SOUTHWEST OF MONGOLIA(GMIT, 2023) ERDENETSOGT Turbat; 1st Supervisor: Prof. Ph.D. Ariunbolor Purvee; 2nd Supervisor: Prof. Dr. Thomas HollenbergThis thesis focuses on the design and analysis of a renewable microgrid system for mines in the southwest of Mongolia, with an emphasis on addressing the energy-intensive nature of mining, diesel use, and CO2 emissions. As a country abundant in renewable energy resources, Mongolia presents a unique opportunity to achieve sustainable solutions in the mining sector. However, despite proven renewable technology and a renewable-rich country, most mining companies have yet to adopt renewable solutions. The methodology employed in this study encompasses several key steps. Firstly, an overview of the legal frameworks and regulations about renewable energy deployment in the mining sector in Mongolia is conducted. Next, a concept design phase is undertaken, integrating solar, wind, energy storage, and diesel generators to create an off-grid hybrid system tailored to the mine's energy requirements. Considerations such as load demand, resource availability, and system reliability are taken into account during the design phase. Modeling and simulation techniques are employed to assess performance and feasibility, evaluating various scenarios to meet energy needs while minimizing diesel fuel usage and CO2 emissions. Furthermore, a detailed business case is developed, considering the initial capital investment, operational costs, and potential financial benefits of the renewable microgrid system. The analysis includes factors such as the payback period, return on investment (ROI), and levelized cost of electricity (LCOE), providing insights into the economic viability of the system for mining operations in Mongolia. The analysis revealed that incorporating a wind turbine in the off-grid hybrid system increased the renewable energy fraction from 28.6% (PV + energy storage) to 88.1% (PV+ energy storage + wind turbine), resulting in a significant reduction in the levelized cost of electricity (LCOE) and operating costs over the life of the mine. However, PV energy systems with a peak capacity of 6 MW offered a more reliable and consistent energy source compared to wind turbines due to low wind speeds and higher installation costs associated with taller hub heights (>50m).