Review of deep learning approaches in solving rock fragmentation problems

One of the most significant challenges of the mining industry is resource yield estimation from visual data. An example would be identification of the rock chunk distribution parameters in an open pit. Solution of this task allows one to estimate blasting quality and other parameters of open-pit mining. This task is of the utmost importance, as it is critical to achieving optimal operational efficiency, reducing costs and maximizing profits in the mining industry. The mentioned task is known as rock fragmentation estimation and is typically tackled using computer vision techniques like instance segmentation or semantic segmentation. These problems are often solved using deep learning convolutional neural networks. One of the key requirements for an industrial application is often the need for real-time operation. Fast computation and accurate results are required for practical tasks. Thus, the efficient utilization of computing power to process high-resolution images and large datasets is essential. Our survey is focused on the recent advancements in rock fragmentation, blast quality estimation, particle size distribution estimation and other related tasks. We consider most of the recent results in this field applied to open-pit, conveyor belts and other types of work conditions. Most of the reviewed papers cover the period of 2018-2023. However, the most significant of the older publications are also considered. A review of publications reveals their specificity, promising trends and best practices in this field. To place the rock fragmentation problems in a broader context and propose future research topics, we also discuss state-of-the-art achievements in real-time computer vision and parallel implementations of neural networks

B2 sequences whose terms are squares

6 páginas.Peer reviewe

High-resolution phase based method for FMCW short range radars

The paper deals with the problem of the using phase-based methods for frequency estimation in the frequency modulated continuum waves (FMCW) short-range radars in the case of high-resolution frequency estimation requirements. The equation is considered for frequency estimation by the least-square method of approximating the phase-to-time relation of the beat signal correlation function in the case of several significant components in the signal (such as valuable and interference signal-like tones). Solution is proposed for the equations by using the parametric (or subspace) decomposition of beat signals (such as eigenvector decomposition, EV). The numerical investigation shows that the bias of the frequency estimations by the proposed solution of the mentioned equation above has statistical properties similar to the method of estimation of signal parameters via rotational invariance techniques (ESPRIT). However, the proposed method does not require the double decompositions, and frequency of each eigenvector can be estimated separately. It is also shown that in the case of the unknown number of signal components the proposed method has the higher statistical properties than for such popular technique as the multiple signal classification method (MUSIC). © 2020 American Institute of Physics Inc.. All rights reserved.The work was supported by Act 211 Government of the Russian Federation, contract N 02.A03.21.0006

The results of U-Pb SHRIMP-II dating of zircon from granitoids of Talitsky molybdenum-bearing massif (eastern slope of the Middle Urals)

Age position and geodynamic conditions of molybdenum metallization and productive granitoids of the Urals formation are very little studied now. This publication contains the results of isotopic dating of granites from Talitsa Cu-Mo-porphyry deposit which should help solve this problem. The timing of formation of the molybdenum-bearing granitoids of Talitsa deposit was determined by applying the U-Pb SHRIMP-II method through zircons (the Center for Isotopic Research of All Russian Geological Research Institute, St.Petersburg). The U-Pb-age has been calculated on 7 (from a total of 11 conduc­ted) measurements with probability of concordanсе 0.996 and MSWD = 0.105 and it is 297.4 ± 2.3 Ma. The results of U-Pb dating are similar to before published Re-Os ages of Talitsa molybdenite deposit: 299.9 ± ± 2.9 Ma and 298.3 ± 1.3 Ma. These data establishes the new unknown before age level of molybdenum metallization. Until recently there has been only data on the Yuzhno-Shameiskoe molybdenum deposit connected with the subalkaline granites of Malyshevo massif which is younger: 277.1 ± 1.1 Ma. According to the received data, the intrusion of investigated granitoids happened practically at the same time as the formation of the wide-spread in the western slope of the Middle Urals intrusive bodies which are accompanied by gold metallization (Verkhisetsky, Shartashsky and others). With such close (practically the same) time of formation the rocks of molybdenum-bearing and gold-bearing massifs significantly differ in petrochemical peculiarities, which probably determines their metallogenetic specialization. Granitoids forming gold-bearing quartz veins on chemical composition are rocks of calc-alkaline series (typical exemple - Shartashskyi massif with Beriozovsk gold deposite). The granitoids productive on of Cu-Mo-porphyry type metallization together with large number of normal alkalinity rocks includes subalkaline rocks such as monzodiorites and quartz monzodiorites

Intersecting Solitons, Amoeba and Tropical Geometry

We study generic intersection (or web) of vortices with instantons inside, which is a 1/4 BPS state in the Higgs phase of five-dimensional N=1 supersymmetric U(Nc) gauge theory on R_t \times (C^\ast)^2 \simeq R^{2,1} \times T^2 with Nf=Nc Higgs scalars in the fundamental representation. In the case of the Abelian-Higgs model (Nf=Nc=1), the intersecting vortex sheets can be beautifully understood in a mathematical framework of amoeba and tropical geometry, and we propose a dictionary relating solitons and gauge theory to amoeba and tropical geometry. A projective shape of vortex sheets is described by the amoeba. Vortex charge density is uniformly distributed among vortex sheets, and negative contribution to instanton charge density is understood as the complex Monge-Ampere measure with respect to a plurisubharmonic function on (C^\ast)^2. The Wilson loops in T^2 are related with derivatives of the Ronkin function. The general form of the Kahler potential and the asymptotic metric of the moduli space of a vortex loop are obtained as a by-product. Our discussion works generally in non-Abelian gauge theories, which suggests a non-Abelian generalization of the amoeba and tropical geometry.Comment: 39 pages, 11 figure

Oka's inequality for currents and applications

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46241/1/208_2005_Article_BF01446636.pd

Safety and tolerability of bazedoxifene in postmenopausal women with osteoporosis: results of a 5-year, randomized, placebo-controlled phase 3 trial

Summary: Findings from this 5-year phase 3 study of postmenopausal women with osteoporosis showed that bazedoxifene was associated with an overall favorable safety and tolerability profile, with no evidence of endometrial or breast stimulation. Overall, the results at 5 years were consistent with those seen at 3 years. Introduction: We report safety and tolerability findings from a 5-year randomized, double-blind, phase 3 study of bazedoxifene in postmenopausal women with osteoporosis. Methods: In the core study, healthy postmenopausal women with osteoporosis (N=7,492; mean age, 66.4 years) were randomized to daily doses of bazedoxifene 20 or 40 mg, raloxifene 60 mg, or placebo for 3 years. During the 2-year study extension, the raloxifene 60-mg treatment arm was discontinued after the 3-year database was finalized, and subjects receiving bazedoxifene 40 mg were transitioned in a blinded manner to bazedoxifene 20 mg (bazedoxifene 40-/20-mg group) after 4 years. Safety and tolerability data are reported for subjects in the bazedoxifene 20- and 40-/20-mg and placebo groups; efficacy findings are reported elsewhere. Results: A total of 3,146 subjects in the bazedoxifene 20- and 40-mg and placebo groups were enrolled in the extension study (years 4 and 5). Overall, the 5-year incidence of adverse events (AEs), serious AEs, and discontinuations due to AEs were similar among groups. The incidence of hot flushes and leg cramps was higher with bazedoxifene compared with placebo. Venous thromboembolic events, primarily deep vein thrombosis, were more frequently reported in the bazedoxifene groups compared with the placebo group. Reports of cardiac disorders and cerebrovascular events were few and evenly distributed among groups. Bazedoxifene showed a neutral effect on the breast and endometrium. Conclusion: Bazedoxifene was associated with an overall favorable safety and tolerability profile in postmenopausal women with osteoporosis over 5 years of therapy, consistent with findings at 3 years. © 2010 International Osteoporosis Foundation and National Osteoporosis Foundation

On the Path to Housing Reform Analysis and Forecast

Slogans and reality The rate of housing construction has accelerated slightly in the four years that have elapsed since the Twenty-seventh CPSU Congress advanced the task of providing virtually every family with a separate apartment or an individual house by the year 2000. However, another slump was seen after the commissioning of housing peaked at 132.4 million square meters in 1988: new housing again declined in 1989. As regards the number of apartments, in 1987 it was only possible to repeat the level of average annual commissioning of 2.26 million in the Sixth Five-Year Plan. But then there was a twofold increase in the commissioning of apartments, whereas now their commissioning increased by only 13 percent compared with the preceding five-year plan. The number of dwellings under construction again declined starting in 1988. At the same time, the waiting list for housing continued to grow; 18 percent of the families have already been on this list for more than ten years. Thus there was no general improvement in housing conditions: we are now farther away from solving the housing problem than we were four years ago.