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Research on determination of haul truck speed depending on mining and technical conditions
No full textOne of the primary methods to enhance the profitability of open-pit mining transportation is to establish and adhere to an operational regime tailored to specific operational and technical conditions. A critical factor defining productivity and safety in these operational regimes is the truck speed. Accurately determining the speed facilitates precise transportation task planning, optimal administrative measures, and operational management capabilities. Several methods exist for determining the speed of dump trucks, with the analytical method commonly used under safety conditions to set speed limits on curvy or steep segments of the road. The graphic-analytical method utilizes dynamics of force and load travel performance to determine the appropriate speed for each road segment. Currently, analytical and graphic-analytical methods used for determining the speed of mining dump trucks are up to 10-15% variance in accuracy, does not fully meet today’s requirements. Mining dump trucks operate in stable and variable motion regimes during a single work cycle, and it is impossible to determine the speed during these various regimes using simple analytical methods alone. However, with the advancement of big data processing today, high-precision measurements and production tests can be conducted, enabling the derivation of mathematical equations and models during these motion regimes, which in turn allows for the programming of the entire dump truck travel in a comprehensive model. This study utilized a large dataset from Erdenet open-pit mining operations to define the influence of operational and technical factors such as mine depth, distance, road gradient, and pavement type on the speed of movement. This methodology enables conducting various analytical tests, developing models, and quickly determining the speed of movement under specific production conditions
Assessing Groundwater Potential and Recharge Zones Using Integrated Remote Sensing and GIS Techniques in Bannu Basin, Pakistan
No full textSurface water has usually served as a reliable source for meeting the water needs of humans. However, rapid urbanization and industrialization have significantly altered water dynamics. This study examined groundwater potential and its recharge sites in the Bannu Basin, Pakistan, using geospatial technologies. The study applied multi-influencing factors and weighted overlay analysis techniques with eight influencing parameters, including land use/land cover, soil, drainage and lineament density, topography, rainfall, geology, and runoff potential. To achieve this, Sentinel-2 (2022) was used to create a land use/land cover layer, and runoff potential was computed using land use/land cover, rainfall, and soil data. The resulting layers were categorized into four classes: excellent, good, moderate, and poor. Overall, the analysis shows that significant groundwater potential justifies 47.92% of the area, which covers the central part, excellent as 4.56% covering a very minor area of 50.14 km2, moderate as 38.96% covering the northeastern and southern parts, while poor accounts for 8.57% of the total study area. As a result, a major part of the area has moderate to good groundwater recharge potential, with a small portion (1.15%) having excellent groundwater potential, whereas poor groundwater recharge potential prevails in 340.33 km2 (7.81%). The study results were confirmed using field data and a groundwater potential map by overlay analysis with the real groundwater table, showing that lower water tables match poor and higher tables with excellent potential zones. This study will help in sustainable groundwater resource management and planning in similar regions
Worldwide distribution of the Glossopteris lineage – The significance of crustal and seawater events
No full textIn support of the continental drift hypothesis, Alfred Wegener considered Glossopteris to be the dominating vegetation of his Gondwana continental merger near the Permian South Pole. But the plant\u27s supposed ability to thrive in polar conditions has remained an enigma that has sparked a flood of ad hoc ecological mechanisms. Also, the glossopteris group of terrestrial vegetation has remained highly controversial, not least with regard to its distribution to all continents. In an attempt to find a reasonable explanation for the seemingly endless riddle, this article addresses two critical questions: the evolution of seawater and that of the deep-sea crust. The evaluation is based entirely on observational rock facts from the geoscientific literature - not from modelling, including inverted satellite gravity-derived seafloor topography. The analysis brings us back to the palaeontologists’ classical land bridges. The Indian Ocean is given special attention. At the end of the Palaeozoic, the original continental crust was still in an early stage of "oceanization", and the generally shallow ocean basins at that time were divided by a network of intercontinental ridges and plateaus. Thus, terrestrial flora and fauna had open migration routes between India, Eurasia, Africa, Australia, Antarctica and the Americas. In the new paleogeographic development scheme, the overwhelming part of the Glossopteris habitat and dispersal routes occurred in tropical to warm mid-latitudes. There are no reasons to believe that glossopteris grew under polar conditions
Standardization Study of Aerial Parts of Iceland Poppy (Papaver Nudicaule L.)
No full textObjective: This study aimed to establish quality standards for the aerial parts of the medicinal plant Iceland poppy (Papaver nudicaule L.). Methods: The anatomical structures of the aerial parts of plants were determined using microscopy. Bioactive compounds were identified and quantified using High-Performance Liquid Chromatography (HPLC). General quality parameters of the aerial parts of the Iceland poppy (Papaver nudicaule L.) were determined using the methods outlined in the European Pharmacopoeia. Results: The plant was collected from gravelly soil along the riverbank near the mouth of the Gorkhi-Terelj Valley in Erdene Soum, Tuv Province. The microstructure of the aerial parts of the Iceland poppy (Papaver nudicaule L.) was determined. The quality parameters of the aerial parts of Iceland poppy (Papaver nudicaule L.) were determined as follows: total ash content 5.54±0.2131%, moisture content 4.11±0.41%, and extractable substances with 70% ethanol were found to be highest at 27.61±0.43%. Additionally, the heavy metal and microbiological purity levels complied with the recommendations of the WHO and the requirements of the European Pharmacopoeia. Conclusion: The standardization criteria for the aerial parts of Papaver nudicaule L. were established. In addition, the pseudoprotopine alkaloid content in the aerial parts of Papaver nudicaule was found to be 0.0288 ± 0.0005%
The effect of a bilateral stellate ganglion block guided by ultrasound on postoperative cognitive function in elderly spinal patients
No full textObjective: Post-operative cognitive dysfunction (POCD) is a prevalent consequence of general anesthesia in older individuals (≥60 years) undergoing spine surgery. Factors associated with spinal surgery (prone positioning, prolonged length, and increased bleeding) along with general anesthesia elevate the risk of postoperative complications. Stellate ganglion block (SGB) exhibits neuroprotective effects via enhancing cerebral microcirculation and decreasing inflammation. This study intends to investigate the influence of bilateral SGB on POCD in these patients. Methods: One hundred fourteen elderly spine surgery patients were randomly assigned to a control group (standard general anesthesia) and a study group (ultrasound-guided bilateral SGB 2 hours pre-anesthesia plus general anesthesia). Cognitive function was evaluated by the MMSE/MoCA at T0 (pre-SGB), T1 (one day post-operation), and T3 (three days post-operation); POCD was categorized by severity. Results: One hundred patients were analyzed (14 excluded). Baseline characteristics were similar between groups (p> 0.05). At 2 hours post-op, no difference was found in cognitive impairment between groups. However, the SGB group had fewer moderate and severe cognitive dysfunction cases (p< 0.05). At 72 hours, no difference in mild cognitive impairment was observed, but the SGB group had lower POCD incidence (p< 0.05). Conclusions: Ultrasound-guided bilateral SGB before anesthesia successfully diminishes moderate-to-severe postoperative cognitive dysfunction within 3 days post-operation in elderly spine surgery patients
Risk Factors of Delayed Graft Function in Patients with Kidney Transplantation
No full textObjective: In Mongolia, since 2006, kidney transplantation has been performed regularly, with more than 400 people having undergone this surgery. This preliminary study aimed to investigate the incidence of delayed graft function after kidney transplantation in Mongolia and to identify the associated risk factors. Methods: This study used a retrospective approach, gathering data from monitoring records. We applied the Student t-test, one-way ANOVA, Wilcoxon rank sum test, Kruskal-Wallis rank test, Spearman correlation, multivariate linear regression, and logistic regression. Results: Of the 268 recipients, 198(74.44%) were male. There were 14 total cases of DGF, of which 13 were transplanted from brain-dead donors. Postoperative urine outcome decreases by 120 mL for a 1-year increase in donor age (b = -120, p= 0.033). A 1-minute increase in cold ischemia time results in a 20-mL decrease in urine output (b = -20, p= 0.002). Donor age>40 increased the risk by 1.2 times (OR=1.2, p= 0.05), and brain-dead donor increased the risk by 19.37 times (OR=19.37, p= 0.0001), while recipient age<35 reduced the risk by 5 times (OR=0.2, p= 0.039). Conclusion: Our study found that risk factors such as older donor and recipient age, prolonged cold and warm ischemia times, and brain-dead donor status were associated with an increased risk of delayed graft function
Some results of the excavation of the xiongnu burial at Ar Gunt
No full textThe Xiongnu cemetery site of Ar Gunt is located in the territory of the 21st khoroo at Songinokhairkhan District, Ulaanbaatar, in the foothills of Jargalant Pass, and is one of the largest Hunnu cemetery in the vicinity of the capital of Mongolia. In 2022, as part of the Mongolian-Hungarian joint project “Study of Historical and Cultural Relations between Asian and European Huns,” archaeological excavations were conducted on seven graves at this site. During the excavations, over 1,250 archaeological and zooarchaeological artifacts and materials were uncovered, including a wide range of human, animal (horse, dog, bird, deer), and other biological remains, creating opportunities for detailed laboratory analyses. In terms of material culture, rare artifacts such as the iron cauldron and the bone-stoppered Dashmag vessel rim were discovered. These items are newly documented in Xiongnu burials for the first time, highlighting the uniqueness and significance of this research. Paleoanthropological studies examined the human bones from the burials to determine age, sex, and biological characteristics. Ancient DNA analysis conducted on samples from burial ArG-06 revealed that the individual was likely associated with an elite group that migrated from the Mongolian Plateau to the Hungarian plains. Radiocarbon dating indicates that the burial dates to the 2nd BC–1st century AD. The Ar Gunt Hunnu cemetery site is an important source for studying the social structure, funerary customs, sacrificial rituals, and cultural interactions between the East and West during the Xiongnu period.
Ар Гүнтийн хүннү булшны малтлага судалгааны зарим үр дүнгээс
Хураангуй. Ар гүнтийн хүннүгийн булш оршуулгын дурсгал нь Улаанбаатар хотын Сонгинохайрхан дүүргийн 21-р хорооны нутаг, Жаргалантын давааны өвөрт орших бөгөөд нийслэл орчмын хамгийн том хүннүгийн булшны цогцолборын нэг юм. Монгол, Унгарын хамтарсан “Азийн хүннүчүүд ба Европын хүннүчүүдийн түүх, соёлын харилцаа, хамаарлын судалгаа” төслийн хүрээнд 2022 онд уг дурсгалт газарт 7 булшинд археологийн малтлага хийв. Малтлагын явцад нийт 1250 гаруй ширхэг археологийн болон зооархеологийн хэрэглэгдэхүүн илэрч, хүн, мал, нохой, шувуу, бугын яс зэрэг олон төрлийн олдвор цуглуулсан нь лабораторийн түвшний нарийвчилсан судалгаа хийх боломжийг бүрдүүллээ. Олдвор хэрэглэгдэхүүний хувьд төмөр тогоо, дашмагийн ясан бөглөөтэй амсар зэрэг ховор эдлэл илэрсэн нь хүннүгийн булшнаас анх удаа бүртгэгдэж буй шинэлэг олдвор бөгөөд энэ нь тус судалгааны онцлог, ач холбогдлыг улам тодотгож байна. Палеоантропологийн шинжилгээгээр булшнууд дахь хүний ясыг судалж, нас, хүйс, биологийн онцлогийг тогтоосон бөгөөд ArG-06 дугаартай булшнаас авсан дээжид хийсэн археогенетикийн судалгаа уг булшны эзэн нь Монголын өндөрлөгөөс Унгарын тал хээрт нүүдэллэн очсон элит бүлэгтэй холбоотой болох, радиокарбоны шинжилгээгээр НТӨ II – НТ I зууны үед хамаарахыг тогтоосон. Ар гүнтийн хүннүгийн оршуулгын дурсгал нь Хүннүгийн нийгмийн бүтэц, оршуулгын зан үйл, тахил, тайлга болон дорно, өрнийн соёлын харилцааг судлахад чухал эх сурвалж болж байна.
Түлхүүр үг: Ар гүнт, хүннүгийн булш, археологийн малтлага, палеоантропологи, радиокарбон шинжилгээ, зооархеологи, оршуулгын зан үй
Ice regime on Khuvsgul lake, Mongolia, detection by time series movement from threshold value with MODIS
No full textIt is essential that any investigation of regime changes be grounded in long-term observational measurements and data. Ice transportation on Lake Khuvsgul plays a vital role in the socio-economic life of the surrounding region. A critical factor for ensuring the safety of ice transportation is the load-bearing strength of the ice. Accordingly, this study is designed to characterize ice phenology and dynamics over the 2003–2024 period using eight-day interval datasets, with ice volume as the principal parameter. In this study, we used MODIS satellite surface‐temperature products to estimate ice‐volume parameters via the Weinberg equation. Threshold values for the ice‐volume parameter were established using Youden’s method, based on the load-bearing strength of the ice. Threshold value distinguishing young or melting ice from growing ice were established at 1089.655 m³ t⁻¹ and 1090.015 m³ t⁻¹. The onset of ice formation occurs when the ice‐surface temperature drops below 0 °C, and melting initiates once it rises above 0 °C. This underscores the exceptional purity of Lake Khuvsgul’s ice
Comparison of machine learning, supervised, and unsupervised algorithms for a land cover classification in northern Mongolia
No full textThe aim of this study is to compare the performance of machine learning approaches alongside supervised and unsupervised techniques to differentiate land cover classes in the northern Mongolia. The primary goal is to identify which of these methods can achieve the highest classification accuracy. For this analysis, we selected ten original spectral bands from Sentinel-2 data and utilized three different feature combinations. To differentiate among the available classes, we employed a support vector machine (SVM), a Mahalanobis distance classifier, and K-means clustering, assessing their relative effectiveness. In the three-band feature combination, K-means obtained the lowest accuracy at 70.08%, whereas SVM achieved 92.72%, ranking it as the most effective method. The Mahalanobis distance classifier closely followed with an accuracy of 90.36%. In the five-band combination, K-means improved its accuracy to 95.56%, surpassing earlier results, while the Mahalanobis distance achieved 95.07%, and SVM recorded an accuracy of 93.33%. In the analysis involving all ten bands, K-means again delivered the highest accuracy at 95.83%. The Mahalanobis distance classifier reached an accuracy of 93.93%, while SVM had an accuracy of 93.14%. In many cases, machine learning techniques can often outperform traditional methods. However, in this study, the traditional unsupervised technique surpassed both machine learning and supervised techniques in two cases. Thus, the results suggest that achieving high accuracy is not invariably attainable with machine learning or supervised image classification methods. In many instances, it depends on the selection of parameters, the data structure, and the radiometric properties of the objects of classes
Interrelated factors influencing the human development potential in the Central region of Mongolia /For example Umnugovi province/
No full textThis article examines the main factors of human potential formation. There is a gradual increase in the human development index in the Umnugovi region. This is due to the influence of various factors that are closely interrelated and have varying degrees of manifestation at the regional level. To assess the degree of influence of factors on human development, a selection of indicators characterizing the situation in the region was made. All indicators are aggregated into four groups of factors and given a total value in the range from zero to one, which allows for a quantitative assessment of the factors. This makes it possible to assess the degree of influence of a particular factor on human potential development, as well as to identify the main problems, the solution of which will contribute to further improvement of human development