2,576 results on '"Lev, V"'
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52. Spiritual and Moral Meanings and Values of the Russian Culture as a Basis for the National and Civil Consciousness Upbringing in the Russian Youth
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Egorychev, Aleksander M., Mardakhaev, Lev V., Akhtyan, Anna G., Sizikova, Valeriya V., and Shimanovskaya, Yanina
- Abstract
The relevance of the problem under study is associated with the actual situation which is characteristic for the present-day Russia and pertaining to the results of the state youth policy being carried out, the level of formation of national and civil consciousness of the Russian young people. The objective of the paper consists in detailing the philosophical bases, meanings and values of the Russian culture that can be used in organizing the upbringing and educational activity of the Russian youth. The leading approach to studying this problem was the culturological one acting as the methodological basis of studying the problem of upbringing of the national and civil consciousness in the Russian young people. The main results of the research have shown that the questions of upbringing of the contemporary Russian young people's civil and patriotic consciousness are understudied. There are only few works of social and pedagogical focus that consider these questions pointedly and productively. The research demonstrates the necessity of introducing the relevant modifications (amendments) concerning the Russian youth to the state social policy. It has to be clearly oriented to organizing the focused and consistent social and pedagogical activity which is aimed at shaping the national and civil consciousness of the rising generation on the basis of meanings and values of the Russian culture. The resulting materials are both of theoretical importance for further exploration of this range of problems and of practical importance for elaboration of objectives, provisions, and content of various state and public projects and programs pertaining to the civil and patriotic upbringing of the rising generation (children, adolescents, young people) and using them within the country's system of education at all levels (pre-school, school, professional, and further ones).
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- 2019
53. Recent progress and development prospects of mobile current sources
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Vladimir V. Sleptsov, Lev V. Kozhitov, Anna O. Diteleva, Dmitry Yu. Kukushkin, and Alena V. Popkova
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Electronics ,TK7800-8360 - Abstract
Physicochemical fundamentals have been developed for the basic design solutions and fabrication technologies of prospective electrolytic power cells with a reusable cell capacity of 350–500 W·h/kg at the first stage and 1000 W·h/kg at the second stage. Along with conventional chemical current sources and ionistors, there are emerging high-performance supercapacitor structures with thin dielectric in the double electric layer and hybrid capacitors in which energy is accumulated in the double electric layer and due to electrochemical processes. This approach reduces the internal resistance of the electrolytic cells thus decreasing the heat emission during operation and therefore providing for a higher specific energy capacity and operation safety, shorter charging time and an increase in specific power. Prospective anode is a nanostructured electrode material in the form of a carbon matrix filled with a nanostructured chemically active material. Promising carbon matrix fillers are Li and its alloys, Si, Al, Na, Sn, Mg, Zn, Ni, Co, Ag, as well as a range of other materials and their compounds. The effect of carbon material specific surface area, dielectric permeability and chemically active material addition on the specific energy capacity has been studied. Theoretical specific energy capacity of metal/air hybrid capacitors has been calculated. Thin-film technological system has been designed for new generation electrode materials in the form of carbon matrices with highly developed surface containing thin tunneling dielectrics and chemically active materials on dielectric surface.
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- 2023
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54. Method of type-C liquefied natural gas tank modeling based on volume optimization for future 'milk-run' exploitation
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Lev V. Ivanov, Alexander Yu. Baranov, and Anna V. Novitskaya
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cryogenic tank design ,type-c tank ,partial filling ,tank optimization ,inland carrier ,small-scale tanker ,liquiefied natural gas ,ventless operation ,Optics. Light ,QC350-467 ,Electronic computers. Computer science ,QA75.5-76.95 - Abstract
Common practice methods of tank design for transportation of liquefied natural gas don’t take into account the specifics of the gas carriers operation under the condition of partial filling of cryogenic tanks. A new method for designing of type-C tank is proposed. Method is based on solving the problem of increasing the volume of transported liquefied natural gas by small-scale inland carriers. The method is based on usage of a number of limiting parameters: minimal allowable ventless operation time, allowable values of the ship’s draft, and the actual duration of voyages between neighboring consumers. The method allows optimizing type, shape, wall thickness, and heat insulation thickness of cryogenic tank. The proposed method is aimed at enlargement of usage of the ship’s hull dimensions. This is achieved by changing the diameter, the distance between centers of the bi-lobe tank, the thickness of the insulation, and the maximum allowable working pressure. An increase in the volume of the tank is achieved by coordination such parameters as the maximum allowable draft of the vessel, the minimum time of ventless storage, and the time of ventless operation under partial filling conditions. The calculation of the ventless operation time is determined by the operating conditions of type-C tanks. The calculation of the heat ingress into the tank takes into account the contact area of liquefied gas and its vapors with the metal wall of the tank. The calculations do not take into account the assumption of thermal equilibrium between the liquid and vapor fractions, which leads to the need to take into account heat transfer from vapor to liquid. The implementation of the method is shown on the example of the modeling of the two-way river-sea type vessel. It is shown that optimization of tank parameters in accordance with proposed criteria can lead to an increase in the volume of transported natural gas by more than 4 %. The method can be used in the development of new and modernization of existing vessel projects to transportation of liquefied natural gas operating in water basins of Lena and Yenisei rivers in the East Siberian region. The described method can also be used in the design of road and rail tanks as well as smallscale bullet tanks for liquefied natural gas.
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- 2023
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55. Interpretable Machine Learning with an Ensemble of Gradient Boosting Machines
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Konstantinov, Andrei V. and Utkin, Lev V.
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Computer Science - Machine Learning ,Statistics - Machine Learning - Abstract
A method for the local and global interpretation of a black-box model on the basis of the well-known generalized additive models is proposed. It can be viewed as an extension or a modification of the algorithm using the neural additive model. The method is based on using an ensemble of gradient boosting machines (GBMs) such that each GBM is learned on a single feature and produces a shape function of the feature. The ensemble is composed as a weighted sum of separate GBMs resulting a weighted sum of shape functions which form the generalized additive model. GBMs are built in parallel using randomized decision trees of depth 1, which provide a very simple architecture. Weights of GBMs as well as features are computed in each iteration of boosting by using the Lasso method and then updated by means of a specific smoothing procedure. In contrast to the neural additive model, the method provides weights of features in the explicit form, and it is simply trained. A lot of numerical experiments with an algorithm implementing the proposed method on synthetic and real datasets demonstrate its efficiency and properties for local and global interpretation.
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- 2020
56. A Generalized Stacking for Implementing Ensembles of Gradient Boosting Machines
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Konstantinov, Andrei V. and Utkin, Lev V.
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Computer Science - Machine Learning ,Statistics - Machine Learning - Abstract
The gradient boosting machine is one of the powerful tools for solving regression problems. In order to cope with its shortcomings, an approach for constructing ensembles of gradient boosting models is proposed. The main idea behind the approach is to use the stacking algorithm in order to learn a second-level meta-model which can be regarded as a model for implementing various ensembles of gradient boosting models. First, the linear regression of the gradient boosting models is considered as a simplest realization of the meta-model under condition that the linear model is differentiable with respect to its coefficients (weights). Then it is shown that the proposed approach can be simply extended on arbitrary differentiable combination models, for example, on neural networks which are differentiable and can implement arbitrary functions of gradient boosting models. Various numerical examples illustrate the proposed approach.
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- 2020
57. Counterfactual explanation of machine learning survival models
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Kovalev, Maxim S. and Utkin, Lev V.
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Computer Science - Machine Learning ,Statistics - Machine Learning - Abstract
A method for counterfactual explanation of machine learning survival models is proposed. One of the difficulties of solving the counterfactual explanation problem is that the classes of examples are implicitly defined through outcomes of a machine learning survival model in the form of survival functions. A condition that establishes the difference between survival functions of the original example and the counterfactual is introduced. This condition is based on using a distance between mean times to event. It is shown that the counterfactual explanation problem can be reduced to a standard convex optimization problem with linear constraints when the explained black-box model is the Cox model. For other black-box models, it is proposed to apply the well-known Particle Swarm Optimization algorithm. A lot of numerical experiments with real and synthetic data demonstrate the proposed method., Comment: arXiv admin note: text overlap with arXiv:2005.02249
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- 2020
58. Gradient boosting machine with partially randomized decision trees
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Konstantinov, Andrei V. and Utkin, Lev V.
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Computer Science - Machine Learning ,Statistics - Machine Learning - Abstract
The gradient boosting machine is a powerful ensemble-based machine learning method for solving regression problems. However, one of the difficulties of its using is a possible discontinuity of the regression function, which arises when regions of training data are not densely covered by training points. In order to overcome this difficulty and to reduce the computational complexity of the gradient boosting machine, we propose to apply the partially randomized trees which can be regarded as a special case of the extremely randomized trees applied to the gradient boosting. The gradient boosting machine with the partially randomized trees is illustrated by means of many numerical examples using synthetic and real data.
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- 2020
59. SurvLIME-Inf: A simplified modification of SurvLIME for explanation of machine learning survival models
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Utkin, Lev V., Kovalev, Maxim S., and Kasimov, Ernest M.
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Computer Science - Machine Learning ,Statistics - Machine Learning - Abstract
A new modification of the explanation method SurvLIME called SurvLIME-Inf for explaining machine learning survival models is proposed. The basic idea behind SurvLIME as well as SurvLIME-Inf is to apply the Cox proportional hazards model to approximate the black-box survival model at the local area around a test example. The Cox model is used due to the linear relationship of covariates. In contrast to SurvLIME, the proposed modification uses $L_{\infty }$-norm for defining distances between approximating and approximated cumulative hazard functions. This leads to a simple linear programming problem for determining important features and for explaining the black-box model prediction. Moreover, SurvLIME-Inf outperforms SurvLIME when the training set is very small. Numerical experiments with synthetic and real datasets demonstrate the SurvLIME-Inf efficiency., Comment: arXiv admin note: substantial text overlap with arXiv:2003.08371, arXiv:2005.02249
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- 2020
60. A robust algorithm for explaining unreliable machine learning survival models using the Kolmogorov-Smirnov bounds
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Kovalev, Maxim S. and Utkin, Lev V.
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Computer Science - Machine Learning ,Statistics - Machine Learning - Abstract
A new robust algorithm based of the explanation method SurvLIME called SurvLIME-KS is proposed for explaining machine learning survival models. The algorithm is developed to ensure robustness to cases of a small amount of training data or outliers of survival data. The first idea behind SurvLIME-KS is to apply the Cox proportional hazards model to approximate the black-box survival model at the local area around a test example due to the linear relationship of covariates in the model. The second idea is to incorporate the well-known Kolmogorov-Smirnov bounds for constructing sets of predicted cumulative hazard functions. As a result, the robust maximin strategy is used, which aims to minimize the average distance between cumulative hazard functions of the explained black-box model and of the approximating Cox model, and to maximize the distance over all cumulative hazard functions in the interval produced by the Kolmogorov-Smirnov bounds. The maximin optimization problem is reduced to the quadratic program. Various numerical experiments with synthetic and real datasets demonstrate the SurvLIME-KS efficiency.
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- 2020
61. SurvLIME: A method for explaining machine learning survival models
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Kovalev, Maxim S., Utkin, Lev V., and Kasimov, Ernest M.
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Computer Science - Machine Learning ,Statistics - Machine Learning - Abstract
A new method called SurvLIME for explaining machine learning survival models is proposed. It can be viewed as an extension or modification of the well-known method LIME. The main idea behind the proposed method is to apply the Cox proportional hazards model to approximate the survival model at the local area around a test example. The Cox model is used because it considers a linear combination of the example covariates such that coefficients of the covariates can be regarded as quantitative impacts on the prediction. Another idea is to approximate cumulative hazard functions of the explained model and the Cox model by using a set of perturbed points in a local area around the point of interest. The method is reduced to solving an unconstrained convex optimization problem. A lot of numerical experiments demonstrate the SurvLIME efficiency.
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- 2020
62. Immunological detection of bone marrow lesions in skin melanoma and its clinical significance: Observational study
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Maria A. Krylovetskaya, Svetlana V. Chulkova, Irina G. Markina, Olga A. Chernysheva, Igor G. Komarov, Olga P. Kolbatskaya, Natalya A. Kupryshina, Andrey V. Logachev, Irina N. Mikhaylova, Lev V. Demidov, and Nikolai N. Tupitsyn
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disseminated tumor cells ,melanoma ,bone marrow ,flow cytometry ,morphology ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Background. Melanoma of the skin is characterized by a rapid progression and early metastasis. It has been shown the disseminated tumor cells, which are often found in the bone marrow, has an important prognostic value. The study of disseminated tumor cells in melanoma might be one of the possible additional sources of information about the nature of the disease and potential application points for drug therapy. Aim. To study the frequency of detection of disseminated tumor cells in the bone marrow in melanoma, depending on the clinical and morphological characteristics of the tumor. Materials and methods. The study included 67 patients with a verified diagnosis of melanoma who were examined and treated at the Blokhin National Medical Research Center of Oncology from 2014 to 2019 years. Male patients accounted for 50.7% (n=34), female patients 49.3% (n=33). The average age of patients: 50.11.6 years. Immunological and morphological examination of the bone marrow were perfomed. Morphological examination was performed by two independent morphologists. Disseminated tumor cells were evaluated by flow cytometry among all nucleated cells (Syto41+) based on the expression of the HMB-45 antigen and the absence of expression of the CD45 panleukocyte antigen (FACS Canto II, USA, Kaluza Analysis v2.1). Statistical data processing was performed using the IBM-SPSS Statistics v.21 Results. Morphologically bone marrow damage was not detected in any case. Disseminated tumor cells (CD45-HMB-45+) in the bone marrow of melanoma patients were detected in 62.7% (n=42) of cases by flow cytometry. The frequency of bone marrow damage in the early stages is not lower than in advanced ones (p=0.029). This is clearly seen in the enlarged analysis. The percentage of DTC detection. At stages I and II was 60.0% (6/10) and 84.6% (11/13), respectively, at stages III and IV 44.4% (8/18) and 65.4% (17/26). In addition, the frequency of detection of disseminated tumor cells in the bone marrow was higher in young patients (p=0.02). There was no correlation between the frequency of bone marrow damage depending on BRAF status. Conclusion. The connection of disseminated tumor cells with the clinical and morphological characteristics of the melanoma has been established. Melanoma is characterized by frequent bone marrow damage, even in the early stages, in young patients.
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- 2023
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63. Combination of encorafenib and binimetinib in the treatment of patients with BRAF-mutated advanced melanoma. Case report
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Kristina V. Orlova, Natalia N. Petenko, Natalia V. Garanina, and Lev V. Demidov
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encorafenib ,binimetinib ,targeted therapy ,braf ,metastatic melanoma ,clinical case ,review ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Background. The need to use BRAF and MEK inhibitors in the treatment of patients with metastatic and/or unresectable BRAF + melanoma in certain clinical situations is beyond doubt nowadays. The medical community need more information about the new combination of targeted therapy approved in Russia, further details on the expected efficacy and tolerability, potential differences from the existing combinations. Aim. To present of the study results and demonstration of our experience with the new generation of targeted therapy encorafenib and binimetinib combination in the treatment of patients with metastatic and/or inoperable BRAF+ melanoma. Materials and methods. We present the clinical case of BRAF+ advanced melanoma patient with multiple metastases in the liver, spleen, mediastinal and abdominal lymph nodes, stomach and bones who is being treated with encorafenib and binimetinib since 2015 with the treatment efficacy and tolerability described in details, as well as the published data on the efficacy and tolerability of this combination from the pivotal phase III study COLUMBUS. Results. High immediate and long-term efficacy, satisfactory tolerability of encorafenib and binimetinib combination are presented. Updated data on progression-free and overall survival in the COLUMBUS study confirmed the long-term efficacy of COMBO450 therapy in patients with advanced melanoma with BRAF V600 mutation. Conclusion. New generation of BRAFi and MEKi combination expands options of systemic therapy for patients with metastatic and/or inoperable BRAF+ melanoma.
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- 2023
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64. Synthesis, structure and electromagnetic properties of FeCoCu/C nanocomposites
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Dmitriy G. Muratov, Lev V. Kozhitov, Irina V. Zaporotskova, Alena V. Popkova, Vitaly A. Tarala, Evgenij Yu. Korovin, and Artem V. Zorin
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Electronics ,TK7800-8360 - Abstract
FeCoCu ternary nanoparticles distributed and stabilized in the carbon matrix of FeCoCu/C metal-carbon nanocomposites have been synthesized using controlled IR pyrolysis of precursors consisting of the “polymer / iron acetylacetate / cobalt and copper acetates” type system obtained by joint dissolution of components followed by solvent removal. The effect of the synthesis temperature on the structure, composition and electromagnetic properties of the nanocomposites has been studied. By XRD was shown that the formation of the FeCoCu ternary nanoparticles occurs due to the interaction of Fe3С with the nanoparticles of the CoCu solid solution. An increase in the synthesis temperature leads to an increase in the size of the metal nanoparticles due to their agglomeration and coalescence as a result of matrix reconstruction. Furthermore, ternary alloy nanoparticles having a variable composition may form depending on the synthesis temperature and the content ratio of the metals. Raman spectroscopy has shown that the crystallinity of the carbon matrix of the nanocomposites increases with the synthesis temperature. The frequency responses of the relative permittivity and permeability of the nanocomposites have been studied at 3–13 GHz. It has been shown that a change in the content ratio of the metals noticeably increases both the dielectric and the magnetic losses. The former loss is caused by the formation of a complex nanostructure of the nanocomposite carbon matrix while the latter one originates from an increase in the size of the nanoparticles and a shift of the natural ferromagnetic resonance frequency to the low-frequency region. The reflection loss has been calculated using a standard method from the experimental data on the frequency responses of the relative permittivity and permeability. It has been shown that the frequency range and the absorption of electromagnetic waves (from –20 to –52 dB) can be controlled by varying the content ratio of the metals in the precursor. The nanocomposites obtained as a result of the experiment deliver better results in comparison with FeCo/C nanocomposites synthesized under similar conditions.
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- 2023
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65. Geophysical methods applied to the sinkhole investigation at the Dead Sea coasts
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Ezersky, Michael, primary, Eppelbaum, Lev V, additional, and Legchenko, Anatoly, additional
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- 2023
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66. Dead Sea evaporite karst, its features, and methods of investigation
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Ezersky, Michael, primary, Eppelbaum, Lev V, additional, and Legchenko, Anatoly, additional
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- 2023
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67. Joint use of different geophysical methods
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Ezersky, Michael, primary, Eppelbaum, Lev V, additional, and Legchenko, Anatoly, additional
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- 2023
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68. An overview of geophysical methods suitable for karst problem resolving
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Ezersky, Michael, primary, Eppelbaum, Lev V, additional, and Legchenko, Anatoly, additional
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- 2023
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69. General introduction to the karst problem
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Ezersky, Michael, primary, Eppelbaum, Lev V, additional, and Legchenko, Anatoly, additional
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- 2023
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70. Discussion, conclusions, and recommendations
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Ezersky, Michael, primary, Eppelbaum, Lev V, additional, and Legchenko, Anatoly, additional
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- 2023
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71. The Possibility of Estimating the Permafrost’s Porosity In Situ in the Hydrocarbon Industry and Environment
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Lev V. Eppelbaum
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permafrost ,porosity ,refreezing time ,shut-in temperature ,hydrocarbon industry ,living areas ,Geology ,QE1-996.5 - Abstract
Global warming firstly influences the permafrost regions where numerous and rich world hydrocarbon deposits are located. Permafrost thawing has caused severe problems in exploring known hydrocarbon deposits and searching for new targets. This process is also dangerous for any industrial and living regions in cold regions. Knowledge of permafrost’s ice and unfrozen water content is critical for predicting permafrost behavior during the water–ice transition. This is especially relevant when ice and permafrost are melting in many regions under the influence of global warming. It is well known that only part of the formation’s pore water turns into ice at 0 °C. After further lowering the temperature, the water phase transition continues, but at gradually decreasing rates. Thus, the porous space is filled with ice and unfrozen water. Laboratory data show that frozen formations’ mechanical, thermal, and rheological properties strongly depend on the moisture content. Hence, porosity and temperature are essential parameters of permafrost. In this paper, it is shown that by combining research in three fields, (1) geophysical exploration, (2) numerical modeling, and (3) temperature logging, it is possible to estimate the porosity of permafrost in situ. Five examples of numerical modeling (where all input parameters are specified) are given to demonstrate the procedure. This investigation is the first attempt to quantitatively analyze permafrost’s porosity in situ.
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- 2024
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72. Nonlinear response of a two-dimensional electron gas in the quantum Hall regime
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Shuichi Iwakiri, Lev V. Ginzburg, Marc P. Röösli, Yigal Meir, Ady Stern, Christian Reichl, Matthias Berl, Werner Wegscheider, Thomas Ihn, and Klaus Ensslin
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Physics ,QC1-999 - Abstract
Breaking of inversion symmetry leads to nonlinear and nonreciprocal electron transport, in which the voltage response does not invert with the reversal of the current direction. Many systems have incorporated inversion symmetry breaking into their band or crystal structures. In this Letter, we demonstrate that a conventional two-dimensional electron gas system with a back gate shows nonreciprocal behavior (with voltage proportional to current squared) in the quantum Hall regime, which depends on the out-of-plane magnetic field and contact configuration. The inversion symmetry is broken due to the presence of the back gate and magnetic field, and our phenomenological model provides a qualitative explanation of the experimental data. Our results suggest a universal mechanism that gives rise to nonreciprocal behavior in gated samples.
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- 2023
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73. An explanation method for Siamese neural networks
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Utkin, Lev V., Kovalev, Maxim S., and Kasimov, Ernest M.
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Computer Science - Machine Learning ,Statistics - Machine Learning - Abstract
A new method for explaining the Siamese neural network is proposed. It uses the following main ideas. First, the explained feature vector is compared with the prototype of the corresponding class computed at the embedding level (the Siamese neural network output). The important features at this level are determined as features which are close to the same features of the prototype. Second, an autoencoder is trained in a special way in order to take into account the embedding level of the Si-amese network, and its decoder part is used for reconstructing input data with the corresponding changes. Numerical experiments with the well-known dataset MNIST illustrate the propose method., Comment: International Scientific Conference Telecommunications, Computing and Control (TELECCON-2019)
- Published
- 2019
74. Estimation of Personalized Heterogeneous Treatment Effects Using Concatenation and Augmentation of Feature Vectors
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Utkin, Lev V., Kots, Mikhail V., and Chukanov, Viacheslav S.
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Statistics - Machine Learning ,Computer Science - Machine Learning - Abstract
A new meta-algorithm for estimating the conditional average treatment effects is proposed in the paper. The main idea underlying the algorithm is to consider a new dataset consisting of feature vectors produced by means of concatenation of examples from control and treatment groups, which are close to each other. Outcomes of new data are defined as the difference between outcomes of the corresponding examples comprising new feature vectors. The second idea is based on the assumption that the number of controls is rather large and the control outcome function is precisely determined. This assumption allows us to augment treatments by generating feature vectors which are closed to available treatments. The outcome regression function constructed on the augmented set of concatenated feature vectors can be viewed as an estimator of the conditional average treatment effects. A simple modification of the Co-learner based on the random subspace method or the feature bagging is also proposed. Various numerical simulation experiments illustrate the proposed algorithm and show its outperformance in comparison with the well-known T-learner and X-learner for several types of the control and treatment outcome functions.
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- 2019
75. Modeling of GERDA Phase II data
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GERDA collaboration, Agostini, Matteo, Bakalyarov, Alexander M., Balata, Marco, Barabanov, Igor, Baudis, Laura, Bauer, Christian, Bellotti, Enrico, Belogurov, Sergej, Bettini, Alessandro, Bezrukov, Leonid, Borowicz, Dariusz, Bossio, Elisabetta, Bothe, Vikas, Brudanin, Victor, Brugnera, Riccardo, Caldwell, Allen, Cattadori, Carla, Chernogorov, Andrey, Comellato, Tommaso, D'Andrea, Valerio, Demidova, Elena V., Di Marco, Natalia, Domula, Alexander, Doroshkevich, Evgenyi, Egorov, Viacheslav, Fischer, Felix, Fomina, Maria, Gangapshev, Albert, Garfagnini, Alberto, Gooch, Chris, Grabmayr, Peter, Gurentsov, Valery, Gusev, Konstantin, Hakenmüller, Janina, Hemmer, Sabine, Hiller, Roman, Hofmann, Werner, Hult, Mikael, Inzhechik, Lev V., Csáthy, Jozsef Janicskó, Jochum, Josef, Junker, Matthias, Kazalov, Vladimir, Kermaïdic, Yoann, Kihm, Thomas, Kirpichnikov, Igor V., Klimenko, Alexander, Kneißl, Raphael, Knöpfle, Karl T., Kochetov, Oleg, Kornoukhov, Vasily N., Krause, Patrick, Kuzminov, Valery V., Laubenstein, Matthias, Lazzaro, Andrea, Lindner, Manfred, Lippi, Ivano, Lubashevskiy, Alexey, Lubsandorzhiev, Bayarto, Lutter, Guillaume, Macolino, Carla, Majorovits, Bela, Maneschg, Werner, Miloradovic, Michael, Mingazheva, Rizalina, Misiaszek, Marcin, Moseev, Pavel, Nemchenok, Igor, Panas, Krysztof, Pandola, Luciano, Pelczar, Krysztof, Pertoldi, Luigi, Piseri, Paolo, Pullia, Alberto, Ransom, Chloe, Riboldi, Stefano, Rumyantseva, Nadezda, Sada, Cinzia, Salamida, Francesco, Schönert, Stefan, Schreiner, Jochen, Schütt, Mario, Schütz, Ann-Katrin, Schulz, Oliver, Schwarz, Mario, Schwingenheuer, Bernhard, Selivanenko, Oleg, Shevchik, Egor, Shirchenko, Mark, Simgen, Hardy, Smolnikov, Anatoly, Stukov, Danila, Vanhoefer, Laura, Vasenko, Andrey A., Veresnikova, Anna, Vignoli, Chiara, von Sturm, Katharina, Wester, Thomas, Wiesinger, Christoph, Wojcik, Marcin, Yanovich, Evgeny, Zatschler, Birgit, Zhitnikov, Igor, Zhukov, Sergey V., Zinatulina, Daniya, Zschocke, Andreas, Zsigmond, Anna J., Zuber, Kai, and Zuzel, Grzegorz
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Nuclear Experiment ,Physics - Instrumentation and Detectors - Abstract
The GERmanium Detector Array (GERDA) experiment at the Gran Sasso underground laboratory (LNGS) of INFN is searching for neutrinoless double-beta ($0\nu\beta\beta$) decay of $^{76}$Ge. The technological challenge of GERDA is to operate in a "background-free" regime in the region of interest (ROI) after analysis cuts for the full 100$\,$kg$\cdot$yr target exposure of the experiment. A careful modeling and decomposition of the full-range energy spectrum is essential to predict the shape and composition of events in the ROI around $Q_{\beta\beta}$ for the $0\nu\beta\beta$ search, to extract a precise measurement of the half-life of the double-beta decay mode with neutrinos ($2\nu\beta\beta$) and in order to identify the location of residual impurities. The latter will permit future experiments to build strategies in order to further lower the background and achieve even better sensitivities. In this article the background decomposition prior to analysis cuts is presented for GERDA Phase II. The background model fit yields a flat spectrum in the ROI with a background index (BI) of $16.04^{+0.78}_{-0.85} \cdot 10^{-3}\,$cts/(kg$\cdot$keV$\cdot$yr) for the enriched BEGe data set and $14.68^{+0.47}_{-0.52} \cdot 10^{-3}\,$cts/(kg$\cdot$keV$\cdot$yr) for the enriched coaxial data set. These values are similar to the one of Gerda Phase I despite a much larger number of detectors and hence radioactive hardware components.
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- 2019
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76. An Adaptive Weighted Deep Forest Classifier
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Utkin, Lev V., Konstantinov, Andrei V., Chukanov, Viacheslav S., Kots, Mikhail V., and Meldo, Anna A.
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Statistics - Machine Learning ,Computer Science - Machine Learning - Abstract
A modification of the confidence screening mechanism based on adaptive weighing of every training instance at each cascade level of the Deep Forest is proposed. The idea underlying the modification is very simple and stems from the confidence screening mechanism idea proposed by Pang et al. to simplify the Deep Forest classifier by means of updating the training set at each level in accordance with the classification accuracy of every training instance. However, if the confidence screening mechanism just removes instances from training and testing processes, then the proposed modification is more flexible and assigns weights by taking into account the classification accuracy. The modification is similar to the AdaBoost to some extent. Numerical experiments illustrate good performance of the proposed modification in comparison with the original Deep Forest proposed by Zhou and Feng.
- Published
- 2019
77. A weighted random survival forest
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Utkin, Lev V., Konstantinov, Andrei V., Chukanov, Viacheslav S., Kots, Mikhail V., Ryabinin, Mikhail A., and Meldo, Anna A.
- Subjects
Statistics - Machine Learning ,Computer Science - Machine Learning - Abstract
A weighted random survival forest is presented in the paper. It can be regarded as a modification of the random forest improving its performance. The main idea underlying the proposed model is to replace the standard procedure of averaging used for estimation of the random survival forest hazard function by weighted avaraging where the weights are assigned to every tree and can be veiwed as training paremeters which are computed in an optimal way by solving a standard quadratic optimization problem maximizing Harrell's C-index. Numerical examples with real data illustrate the outperformance of the proposed model in comparison with the original random survival forest.
- Published
- 2019
78. Long-term outcomes in patients with BRAF V600-mutant metastatic melanoma receiving dabrafenib monotherapy: Analysis from phase 2 and 3 clinical trials
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Hauschild, Axel, Ascierto, Paolo A, Schadendorf, Dirk, Grob, Jean Jacques, Ribas, Antoni, Kiecker, Felix, Dutriaux, Caroline, Demidov, Lev V, Lebbé, Céleste, Rutkowski, Piotr, Blank, Christian U, Gutzmer, Ralf, Millward, Michael, Kefford, Richard, Haas, Tomas, D'Amelio, Anthony, Gasal, Eduard, Mookerjee, Bijoyesh, and Chapman, Paul B
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Biomedical and Clinical Sciences ,Clinical Sciences ,Oncology and Carcinogenesis ,Cancer ,Clinical Research ,Clinical Trials and Supportive Activities ,6.1 Pharmaceuticals ,Evaluation of treatments and therapeutic interventions ,Adult ,Aged ,Aged ,80 and over ,Antineoplastic Agents ,Dacarbazine ,Disease Progression ,Female ,Follow-Up Studies ,Humans ,Imidazoles ,Male ,Melanoma ,Middle Aged ,Oximes ,Patient Selection ,Progression-Free Survival ,Proto-Oncogene Proteins B-raf ,Skin Neoplasms ,Time Factors ,Young Adult ,BRAF ,Dabrafenib ,Metastatic ,Long-term outcomes ,Public Health and Health Services ,Oncology & Carcinogenesis ,Oncology and carcinogenesis - Abstract
BackgroundPrevious analyses of BREAK-2 and BREAK-3 showed that durable outcomes lasting ≥3 years are achievable with dabrafenib in some patients with BRAF V600-mutant metastatic melanoma (MM); however, additional follow-up is needed to fully characterise the long-term impact of dabrafenib in these patients.MethodsBREAK-2 was a single-arm phase 2 study evaluating dabrafenib in treatment-naive or previously treated BRAF V600E/K-mutant MM. BREAK-3, a randomised (3:1) phase 3 study, assessed dabrafenib versus dacarbazine in previously untreated unresectable or metastatic BRAF V600E-mutant melanoma. Five-year analyses were performed.ResultsAll BREAK-2 patients (N = 92 [V600E, n = 76; V600K, n = 16]) discontinued treatment by the data cutoff. Median follow-up was 13.0 months. In BRAF V600E patients, 5-year progression-free survival (PFS) and overall survival (OS) were 11% and 20%, respectively. Subsequent immunotherapy was received by 22% of patients. In BREAK-3, median follow-up was 17.0 and 12.0 months in the dabrafenib (n = 187) and dacarbazine (n = 63) arms, respectively. Thirty-seven patients (59%) receiving dacarbazine crossed over to dabrafenib following disease progression as per protocol. Five-year PFS was 12% in the dabrafenib arm; all dacarbazine-arm patients progressed or were censored by 5 years. Dabrafenib improved PFS versus dacarbazine, regardless of baseline lactate dehydrogenase levels. Five-year OS rates were 24% and 22% in the dabrafenib and dacarbazine arms, respectively. Subsequent therapy in each arm included anti-CTLA-4 (dabrafenib [24%] and dacarbazine [24%]) and/or anti-PD-1 (8% and 2%) treatment. No new safety signals were observed.Conclusions and relevanceThese data, representing extended follow-up for dabrafenib monotherapy, demonstrate that durable benefit lasting ≥5 years is achievable in a subset of patients.Trial registrationClinicalTrials.gov (BREAK-2, NCT01153763; BREAK-3, NCT01227889).
- Published
- 2020
79. Real-world efficacy of the first line therapy with prolgolimab in patients with metastatic melanoma: interim results of the FORA (FOrteca Real practice Assessment) observational study
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Kristina V. Orlova, Mikhail Yu. Fedyanin, Konstantin E. Simanenkov, Aleksandr S. Dergunov, Petr R. Goldshmidt, Aleksandra F. Saydullaeva, Dary V. Bogacheva, Marina A. Yavorskaya, Artur Z. Azanov, Alexander A. Fedenko, Larisa V. Bolotina, Tatyana I. Deshkina, Kseniya G. Babina, Ekaterina A. Kuzevanova, Liudmila G. Zhukova, Polina S. Feoktistova, Natalya I. Polshina, Ekaterina V. Peganova, Valentina E. Shikina, Maksim M. Sobolev, Oleg V. Mironov, Vera A. Vaschenko, Mariya M. Ershova, Agniya O. Mezhueva, Svetlana A. Orlova, Denis A. Tantsyrev, Darya K. Taskina, Antonina A. Teterich, Elena V. Karabina, Yuliya V. Kostalanova, Marina V. Bogacheva, Natalia V. Zhukova, Rashida V. Orlova, Maksim V. Zinkevich, Aleksandr I. Kazmin, Mikhail V. Volkonskiy, Liya M. Voronkova, Anastasiya S. Karpova, Mikhail L. Maleyko, Mariya N. Gorshenina, Elena I. Kryuchkova, Fedor V. Moiseenko, Yuliya I. Murzina, Shamil I. Musin, Andrey N. Ogloblin, Mariya S. Perminova, Regina A. Dumbrava, Sergey A. Emelyanov, Svetlana A. Protsenko, Alexander V. Sultanbaev, Anna V. Tarasova, Elena B. Shakhnovich, Marina V. Demchenkova, Yuliya A. Lozovskaya, Khedi S. Musaeva, Elena M. Pavlova, Roman A. Skotnikov, Vera V. Chernova, Angelina S. Chichkanova, Adina M. Akhmatova, Marina A. Zafirova, Andrey A. Mischenko, Elena N. Ovsienko, Viktoriya A. Petrukhnenko, Oksana A. Syusyukaylova, Yana A. Tyugina, Elena A. Shumilkina, Daniil L. Stroyakovskiy, Aleksandr N. Yurchenkov, Pavel L. Baldin, Anastasiya S. Belova, Olga V. Diduk, Elena A. Konovalova, Lyudmila N. Lebedeva, Yaroslav A. Li, Viktoriya V. Mashtapa, Yana A. Mironenkova, Kristina V. Narovenkova, Olga A. Pavlikova, Elvira L. Parsadanova, Irina S. Pimonova, Anna A. Ruzhnikova, Irina D. Sivunova, Ekaterina P. Soloveva, Maksim I. Sosnin, Toita Kh. Temirsultanova, Makhabbat Zh. Tyulegenova, Aleksandra V. Khodkevich, Nadezhda R. Shakurova, Sureya N. Efendieva, Karine L. Avagimyan, Ekaterina P. Anokhina, Mariya I. Antoshkina, Stanislav M. Borzyanitsa, Samir K. Dzhentemirov, Marina V. Dmitrochenko, Alla V. Zheleznyak, Yuliya V. Komoza, Aleksandr S. Kopanev, Tatyana I. Kornienko, Margarita A. Krasilnikova, Darya A. Lukhmanova, Natalya S. Mazur, Polina M. Markina, Zhargal S. Mitapov, Svetlana N. Osodoeva, Irina A. Prokopenko, Irina M. Radyukova, Madina S. Ramazanova, Alfiya R. Safarova, Mariya A. Safronova, Khalimat M. Khabrieva, Natalya S. Tsygankova, Kseniya V. Chermakova, Tatyana A. Chirkova, Igor V. Samoylenko, Valeria V. Nazarova, Angelina E. Akhmetyanova, and Lev V. Demidov
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metastatic melanoma ,prolgolimab ,anti-pd1 ,prospective observational study ,braf ,fora ,skin melanoma ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Background. Novel agents immune checkpoint inhibitors fundamentally changed the prognosis for life in patients with metastatic and/or inoperable melanoma. The development, studies, and approval of a new original PD1 inhibitor in Russia in 2020 prompted the professional community to conduct a prospective observational study in the Russian Federation to assess the real-world efficacy and safety of prolgolimab, as real-world patients differ from the refined population in clinical trials. Aim. To evaluate the real-world efficacy and safety of prolgolimab in patients with metastatic and/or inoperable melanoma. Materials and methods. From October 2020 to October 2022, the study enrolled 700 patients with metastatic and/or inoperable melanoma receiving prolgolimab in real clinical settings in oncological institutions of various levels in the Russian Federation. The main inclusion criteria were: pathology-confirmed diagnosis of melanoma, metastatic and/or inoperable type, use of prolgolimab outside of clinical trials, and signed informed consent by the patient. Objective response rate (ORR) was considered the main criterion for evaluating the efficacy of therapy, and the safety criterion was the incidence of grade 34 adverse events. Statistical analysis was performed using the SPSS 20.0 software package. Results. The ORR for patients with skin melanoma treated with prolgolimab in the first line therapy (n= 207/337) was 48.3% (n=100), the disease stabilization was reported in 30.4% (n=63), and progression in 21.3% (n=44) of patients. There were no significant differences in response to therapy between patients with/withoutBRAFmutation, although ORR was higher in patients withBRAFmutation: the ORR for patients withBRAFmutation was 57.9% (n=33), and forBRAFnon-mutated patients, 44.4% (n=52;p=0.222). At a median follow-up of 5 months, the median PFS was 10 months (95% confidence interval 7.3512.64). The incidence of grade 34 treatment-related adverse events according to CTCAE 5.0 was 2% (n=12), and 12% (n=82) for grade 12 adverse events. Conclusion. The results confirm the high efficacy and satisfactory tolerability of prolgolimab in patients with metastatic and/or inoperable melanoma in real-world settings. There were no significant differences in ORR between patients with or withoutBRAFmutation.
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- 2023
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80. Attention-Based Random Forests and the Imprecise Pari-Mutual Model
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Utkin, Lev V., primary, Konstantinov, Andrei V., additional, and Politaeva, Natalia A., additional
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- 2023
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81. Neural Attention Forests: Transformer-Based Forest Improvement
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Konstantinov, Andrei V., primary, Utkin, Lev V., additional, Lukashin, Alexey A., additional, and Muliukha, Vladimir A., additional
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- 2023
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82. AGBoost: Attention-based Modification of Gradient Boosting Machine.
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Andrei V. Konstantinov, Lev V. Utkin, and Stanislav Kirpichenko
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- 2022
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83. Multiple Instance Learning through Explanation by Using a Histopathology Example.
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Andrei V. Konstantinov and Lev V. Utkin
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- 2022
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84. Effect of vacuum sintering conditions on the properties of Y3Al5O12 : Ce luminescent ceramics
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Lyudmila V. Tarala, Alexander A. Kravtsov, Oleg M. Chapura, Vitaly A. Tarala, Dmitry S. Vakalov, Fedor F. Malyavin, Sergey V. Kuznetsov, Viacheslav A. Lapin, Lev V. Kozhitov, and Alena V. Popkova
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Electronics ,TK7800-8360 - Abstract
The aim of this work was to study the effect of vacuum sintering conditions and cerium concentration on the optical, luminescent and thermal properties of yttrium-aluminum garnet based ceramics doped with Се3+ cations. Series of ceramic powders were synthesized and samples of luminescent ceramics having the composition Y3-хСехAl5O12 were synthesized where x was in the range 0.01 to 0.025 f.u. We show that the phase composition and grain size distribution of the ceramic powders do not depend on cerium concentration. Without sintering additives, an increase in vacuum sintering temperature from 1675 to 1800 °C leads to an increase in the optical transmittance of luminescent ceramic specimens from 5 to 55% at a 540 nm wavelength and an increase in the thermal conductivity of the samples from 8.4 to 9.5 W/(m ∙ K). It was found that an increase in cerium concentration leads to a shift of the luminescent band peak from 535 to 545 nm where as the width of the luminescent band decreases with an increase in vacuum sintering temperature from 1675 to 1725 °C.
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- 2022
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85. A-B Transition in Superfluid $$^3$$He and Cosmological Phase Transitions
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Hindmarsh, Mark, primary, Sauls, J. A., additional, Zhang, Kuang, additional, Autti, S., additional, Haley, Richard P., additional, Heikkinen, Petri J., additional, Huber, Stephan J., additional, Levitin, Lev V., additional, Lopez-Eiguren, Asier, additional, Mayer, Adam J., additional, Rummukainen, Kari, additional, Saunders, John, additional, and Zmeev, Dmitry, additional
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- 2024
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86. WS06.06 Safety and efficacy of a nebulized phage cocktail in cystic fibrosis patients with chronic Pseudomonas aeruginosa pulmonary infection: a phase 1b/2a randomized, double-blind, placebo-controlled study
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Kerem, E., primary, Rappo, U., additional, Cohen, A., additional, Maimon, I., additional, Kario, E., additional, Gold, J., additional, Nevenzal, H.-T., additional, Levy-Saar, I., additional, Cohen, T., additional, Weiner, I., additional, Livnat, H. Sberro, additional, Slutskin, I. Vainberg, additional, Jablonska, J., additional, Mordoch, R., additional, Axelrod, T., additional, Bahar, O., additional, Buchshtab, N., additional, Lev, V., additional, Tzur, Y., additional, Zarchin, Y., additional, Golembo, M., additional, Vilchez, R., additional, and Bassan, M., additional
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- 2024
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87. Multi-attention multiple instance learning
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Konstantinov, Andrei V. and Utkin, Lev V.
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- 2022
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88. Evidence for a Spatially-Modulated Superfluid Phase of $^3$He under Confinement
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Levitin, Lev V., Yager, Ben, Sumner, Laura, Cowan, Brian, Casey, Andrew J., Zhelev, Nikolay, Bennett, Robert G., Parpia, Jeevak M., and Saunders, John
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Condensed Matter - Other Condensed Matter ,Condensed Matter - Superconductivity - Abstract
In superfluid $^3$He-B confined in a slab geometry, domain walls between regions of different order parameter orientation are predicted to be energetically stable. Formation of the spatially-modulated superfluid stripe phase has been proposed. We confined $^3$He in a 1.1 $\mu$m high microfluidic cavity and cooled it into the B phase at low pressure, where the stripe phase is predicted. We measured the surface-induced order parameter distortion with NMR, sensitive to the formation of domains. The results rule out the stripe phase, but are consistent with 2D modulated superfluid order., Comment: 9 pages, 9 figures
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- 2018
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89. Can the Applied Optics Employ Modern Approaches Developed in Seismic Prospecting? A Review
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Alexander Berkovitch and Lev V. Eppelbaum
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complex media ,seismic inversion ,boundary conditions ,homeomorphic imaging ,design of optical systems ,Physics ,QC1-999 - Abstract
The concept of infinitesimal elastic deformation and the theory of elastic seismic waves was formed in the first part of the 19th century and was based mainly on the Fermat, Huygens and Snell developments in the theory of optics. At the same time, seismic wave propagation (utilized in geophysical prospecting) and optic wave propagation through defined media are based on the same physical-mathematical principles, making it possible to transfer nonconventional procedures developed in the first domain to the second one and back. In this investigation, we propose transferring advanced methodologies established in seismic prospecting to practical optics. We selected two advanced approaches with the following aims: (a) homeomorphic imaging; (b) novel description of boundary conditions. The first approach is established with the utilization of the revealed local theoretical relationship between the geometrical features of two fundamental beams and the geometrical properties of hidden geological targets of the media under study. The employed geometrical characteristics of the fundamental beams are spreading functions and curvatures of the singular wavefronts. The second approach is based on a novel description of the boundary conditions. It enables the determination of a faultless seismic (optical) system with the preassigned focusing and imaging assets when any aberrations are absent. An optimal optical system is usually determined as some arrangement agreeing to some perfect system with acceptable correctness. Employment of the developed procedures in the optical design will permit the application of a description of the optical surface using: (1) parametric functions, (2) differential equations, and (3) mixed (parametric-differential). On this basis, optical systems with a minimal number of optical features with complicated shapes can be promptly computed. Another important application field of the suggested methods is the design of optical systems with diffractive elements.
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- 2022
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90. Cooling low-dimensional electron systems into the microkelvin regime
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Levitin, Lev V., van der Vliet, Harriet, Theisen, Terje, Dimitriadis, Stefanos, Lucas, Marijn, Corcoles, Antonio D., Nyéki, Ján, Casey, Andrew J., Creeth, Graham, Farrer, Ian, Ritchie, David A., Nicholls, James T., and Saunders, John
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- 2022
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91. SurvNAM: The machine learning survival model explanation
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Utkin, Lev V., Satyukov, Egor D., and Konstantinov, Andrei V.
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- 2022
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92. Protein biosensor based on Schottky barrier nanowire field effect transistor
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Smolyarova, Tatyana E., Shanidze, Lev V., Lukyanenko, Anna V., Baron, Filipp A., Krasitskaya, Vasilisa V., Kichkailo, Anna S., Tarasov, Anton S., and Volkov, Nikita
- Published
- 2022
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93. A simple genome-wide association study algorithm
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Utkin, Lev V. and Utkina, Irina L.
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Quantitative Biology - Quantitative Methods ,Statistics - Machine Learning - Abstract
A computationally simple genome-wide association study (GWAS) algorithm for estimating the main and epistatic effects of markers or single nucleotide polymorphisms (SNPs) is proposed. It is based on the intuitive assumption that changes of alleles corresponding to important SNPs in a pair of individuals lead to large difference of phenotype values of these individuals. The algorithm is based on considering pairs of individuals instead of SNPs or pairs of SNPs. The main advantage of the algorithm is that it weakly depends on the number of SNPs in a genotype matrix. It mainly depends on the number of individuals, which is typically very small in comparison with the number of SNPs. Numerical experiments with real data sets illustrate the proposed algorithm.
- Published
- 2017
94. Discriminative Metric Learning with Deep Forest
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Utkin, Lev V. and Ryabinin, Mikhail A.
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Statistics - Machine Learning ,Computer Science - Learning ,68T10 - Abstract
A Discriminative Deep Forest (DisDF) as a metric learning algorithm is proposed in the paper. It is based on the Deep Forest or gcForest proposed by Zhou and Feng and can be viewed as a gcForest modification. The case of the fully supervised learning is studied when the class labels of individual training examples are known. The main idea underlying the algorithm is to assign weights to decision trees in random forest in order to reduce distances between objects from the same class and to increase them between objects from different classes. The weights are training parameters. A specific objective function which combines Euclidean and Manhattan distances and simplifies the optimization problem for training the DisDF is proposed. The numerical experiments illustrate the proposed distance metric algorithm., Comment: arXiv admin note: substantial text overlap with arXiv:1704.08715
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- 2017
95. A Siamese Deep Forest
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Utkin, Lev V. and Ryabinin, Mikhail A.
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Statistics - Machine Learning ,Computer Science - Learning ,68T10 - Abstract
A Siamese Deep Forest (SDF) is proposed in the paper. It is based on the Deep Forest or gcForest proposed by Zhou and Feng and can be viewed as a gcForest modification. It can be also regarded as an alternative to the well-known Siamese neural networks. The SDF uses a modified training set consisting of concatenated pairs of vectors. Moreover, it defines the class distributions in the deep forest as the weighted sum of the tree class probabilities such that the weights are determined in order to reduce distances between similar pairs and to increase them between dissimilar points. We show that the weights can be obtained by solving a quadratic optimization problem. The SDF aims to prevent overfitting which takes place in neural networks when only limited training data are available. The numerical experiments illustrate the proposed distance metric method.
- Published
- 2017
96. The group behavior analysis of the high-frequency traders based on Mean Field Games approach.
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Egorov, Lev V. and Trusov, Nikolai V.
- Subjects
- *
OPTIMAL control theory , *RICCATI equation , *BEHAVIORAL assessment , *INVERSE problems , *PROBLEM solving - Abstract
We present an approach to describe the group behavior of the high-frequency traders in the stock market based on Mean Field Games and optimal control theory. The problem is formalized as a system of coupled PDEs: Kolmogorov–Fokker–Planck, evolving forward in time with initial condition, and Hamilton–Jacobi–Bellman, evolving backwards in time with terminal condition. Under certain assumptions, the system of PDEs can be reduced to Riccati-type ODEs. We solve the inverse problem to describe the behavior of the high-frequency traders during the Chinese stock market crisis in 2015. [ABSTRACT FROM AUTHOR]
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- 2024
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97. Histopathological and Immunohistochemical Characteristics of Different Types of Cardiac Amyloidosis.
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Gioeva, Zarina V., Mikhaleva, Liudmila M., Gutyrchik, Nikita A., Volkov, Alexey V., Popov, Mikhail A., Shakhpazyan, Nikolay K., Pechnikova, Valentina V., Midiber, Konstantin Y., Reznik, Elena V., and Kakturskij, Lev V.
- Subjects
IMMUNOGLOBULIN light chains ,CARDIAC amyloidosis ,AMYLOID plaque ,HEART failure patients ,AMYLOIDOSIS ,AUTOPSY - Abstract
Cardiac involvement is the most important factor determining prognosis in patients with systemic amyloidosis. This retrospective observational study of 98 patients with amyloidosis was undertaken to assess the amyloid types that are most likely to affect the heart, describe histopathological and clinical features of cardiac amyloidosis, and estimate the number of cases not diagnosed clinically prior to death. All cases were divided into two groups based on the method of examination. The first group included 46 patients with cardiac amyloidosis revealed via endomyocardial biopsies (EMBs), and the second group included 52 amyloidosis patients who did not undergo EMBs, in whom cardiac involvement was identified only at autopsy. The EMBs demonstrated that AL amyloidosis was detected in 21 (46%) specimens, ATTR amyloid in 24 cases (52%), and AA amyloid in 1 case (2%). The autopsy reports defined 15 (46%) cases of AL amyloidosis, 21 (40%) of ATTR and 16 (31%) of AA amyloidosis. It should be noted that a clinical diagnosis of ATTR amyloidosis was made only in 9.5% of patients from the autopsy group, suggesting that ATTR may be an underdiagnosed cause of heart failure in elderly patients. The most intense amyloid deposits were determined in biopsy and autopsy specimens of patients with AL kappa amyloidosis, underlying a poorer prognosis. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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98. Wireless Ranging by Evaluating Received Signal Strength of UWB Chaotic Radio Pulses: Effects of Signal Propagation Conditions.
- Author
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Efremova, Elena V. and Kuzmin, Lev V.
- Subjects
CONFERENCE rooms ,COMMUNICATION barriers ,PROBLEM solving ,SIGNALS & signaling ,ROADSIDE improvement - Abstract
Ultra-wideband radio signals have been the subject of study for several decades. They are used to solve problems of communications and ranging. Measuring the strength (power) of a radio signal is a technically simple way to estimate the distance between the emitter and the receiver of the signal. However, the conditions of signal propagation have a significant impact on the power of the received signal. This work is relevant because chaotic radio pulses are a relatively new type of carrier in wireless technologies, and actual knowledge about the change in signal power in different types of premises is relatively small, so such a study is necessary. In this paper, we study the variation in signal power with distance for chaotic ultra-wideband radio pulses under various propagation conditions. Using experimental measurements in several outdoor (field, roadside) and indoor (corridors, conference room, office) environments, we investigate the effect of propagation conditions on ultra-wideband chaotic radio signals and determine the limits within which the dependence of the calculated power on distance can be approximated by a power law. For this purpose, the results of experimental measurements of the received signal power (a total of about 17.5 M values) were accumulated and analyzed. The accuracy of distance measurement that can be achieved in different conditions is compared and analyzed. It was found that for a 9.5 dBm signal, the range of distances at which the average accuracy is only 15–50 cm when using a power law is 5–7 m indoors and 10–15 m outdoors. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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99. Long distance electron-electron scattering detected with point contacts
- Author
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Lev V. Ginzburg, Yuze Wu, Marc P. Röösli, Pedro Rosso Gomez, Rebekka Garreis, Chuyao Tong, Veronika Stará, Carolin Gold, Khachatur Nazaryan, Serhii Kryhin, Hiske Overweg, Christian Reichl, Matthias Berl, Takashi Taniguchi, Kenji Watanabe, Werner Wegscheider, Thomas Ihn, and Klaus Ensslin
- Subjects
Physics ,QC1-999 - Abstract
We measure electron transport through point contacts in an electron gas in AlGaAs/GaAs heterostructures and graphene for a range of temperatures, magnetic fields, and electron densities. We find a magnetoconductance peak around B=0. With increasing temperature, the width of the peak increases monotonically, while its amplitude first increases and then decreases. For GaAs point contacts the peak is particularly sharp at relatively low temperatures T≈1.5K: the curve rounds on a scale of a few tens of microteslas, hinting at length scales of several millimeters for the corresponding scattering processes. We propose a model based on the transition between different transport regimes with increasing temperature: from ballistic transport to few electron-electron scatterings to hydrodynamic superballistic flow to hydrodynamic Poiseuille-like flow. The model is in qualitative and, in many cases, quantitative agreement with the experimental observations.
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- 2023
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100. Geodynamic Aspects of Magnetic Data Analysis and Tectonic–Paleomagnetic Mapping in the Easternmost Mediterranean: A Review
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Lev V. Eppelbaum, Youri I. Katz, and Zvi Ben-Avraham
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paleomagnetic mapping ,magnetic data analysis ,tectonic–structural interpretation ,ocean-continent junction zone ,counterclockwise rotation ,Easternmost Mediterranean ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The Easternmost Mediterranean is a transition region from the ocean to the continent where the spreading and collision zones of the lithospheric plates join. The methodology of paleomagnetic mapping of the transition zones is based on combining geological and geophysical techniques for continental and oceanic platforms: magnetic data interpretation, paleomagnetic reconstructions, results of magnetized rock radiometric dating, satellite data analysis, tectonic–structural reconstructions, biogeographical studies, and utilization of different geophysical survey results. The satellite-derived gravity map reflects practically all significant tectonic units in the region, which assists us in the supposed paleomagnetic mapping. The satellite-derived and aeromagnetic maps with the tectonic features and the map of Curie discontinuity of Israel indicate the complexity of this region. Advanced magnetic data analysis supported by paleomagnetic data attraction and other geological–geophysical methods allowed the revealing of the block of oceanic crust with the Kiama paleomagnetic zone relating to the Early Permian age. A narrow reversely magnetized Earth crust block was revealed in the Lower Galilee. Some examples of advanced magnetic anomaly analysis are presented for several areas where the magnetization vector inclination is other than the modern direction: the Sea of Galilee, Carmel, Rosh-Ha-Ayin, Malqishon, and Hebron. In Israeli land, for the combined paleomagnetic mapping, the well-studied using paleomagnetic and radiometric methods (as well as tectonic–structural) areas were selected: (1) Makhtesh Ramon, (2) the Sea of Galilee with the adjoining zones, (3) Carmel, (4) Hula, and (5) Hermon. It is shown that the regional analysis of paleomagnetic data distribution played an essential role in detecting the influence of the recently recognized counterclockwise rotating mantle structure on the near-surface layers.
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- 2023
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