The results of numerical analysis of turbine flow capacity and other parameters at different turbine rows are presented in this paper. Mass flow calculations by 3D Euler code has been controlled by means of 3D Navier-...The results of numerical analysis of turbine flow capacity and other parameters at different turbine rows are presented in this paper. Mass flow calculations by 3D Euler code has been controlled by means of 3D Navier-Stokes code taking into account inlet turbulence intensity and turbulence scale. The use of complicated numerical approaches (3D Euler or 3D Navier-Stokes codes) for mass flow definition demands close attention to quality of numerical techniques. Various reasons of inaccuracy of mass flow definition by using different 3D numerical approaches are analyzed.展开更多
BACKGROUND Peritoneal metastasis(PM),arising from gastric cancer(GC),is the most common pattern of synchronous and metachronous dissemination and is generally associated with poor prognosis.New therapeutic modalities ...BACKGROUND Peritoneal metastasis(PM),arising from gastric cancer(GC),is the most common pattern of synchronous and metachronous dissemination and is generally associated with poor prognosis.New therapeutic modalities are being increasingly employed for such patients.AIM To develop more advanced methods,it becomes necessary to study the results of existing standard treatment methods in patients with PM in order to perform a comparative analysis of the strategies.METHODS A retrospective analysis of the efficiency of standard treatment methods(i.e.,palliative chemotherapy,palliative gastrectomy,and the best supportive care)was performed on 200 GC patients with synchronous PM.RESULTS The overall survival(OS)rate in 200 GC patients with PM under standard treatment was 5.4 mo.One-year survival occurred in 18.4%of patients.In multivariate analysis,the survival rate was significantly influenced by the following factors:Presence of extraperitoneal metastases,and stage of PM according to both the Japanese Gastric Cancer Association(JGCA)and the peritoneal cancer index(PCI).The median OS and 1-year survival of patients withР1,P2,and P3(JGCA)carcinomatosis were 9.8 mo,6.7 mo,and 4.0 mo,and 47.2%,18.8%,and 5.1%,respectively.The application of the palliative gastrectomy resulted in an increase in the median OS by up to 17 mo compared to the conservative approach where the value was 8.5 mo(P=0.05)in patients withР1РМ.In patients withР3,palliative chemotherapy increased the OS by up to 5.6 mo compared to the OS of 3.2 mo(P=0.0006)for best supportive care.The median OS and 1-year survival of patients withРCI of 1-6,7-12 and 13+points were 8.5 mo,4.2 mo,and 4.1 mo,and 39.8%,6.7%,and 5.5%,respectively.Palliative gastrectomy increased the median OS to 12.6 mo compared to conservative approach of 8.0 mo(P=0.03)in patients withРCI of 1-6 points.In patients withРCI 13+points,only palliative chemotherapy increased the OS to 6.0 mo compared to the OS of 3.4 mo for best supportive care(P=0.0008).CONCLUSION GC patients with PM are 展开更多
In this paper, we consider operators arising in the modeling of renewable systems with elements that can be in different states. These operators are functional operators with non-Carlemann shifts and they act in Holde...In this paper, we consider operators arising in the modeling of renewable systems with elements that can be in different states. These operators are functional operators with non-Carlemann shifts and they act in Holder spaces with weight. The main attention was paid to non-linear equations relating coefficients to operators with a shift. The solutions of these equations were used to reduce the operators under consideration to operators with shift, the invertibility conditions for which were found in previous articles of the authors. To construct the solution of the non-linear equation, we consider the coefficient factorization problem (the homogeneous equation with a zero right-hand side) and the jump problem (the non-homogeneous equation with a unit coefficient). The solution of the general equation is represented as a composition of the solutions to these two problems.展开更多
Following the classical definition of factorization of matrix-functions, we introduce a definition of factorization for functional operators with involutive rotation on the unit circle. Partial indices are defined and...Following the classical definition of factorization of matrix-functions, we introduce a definition of factorization for functional operators with involutive rotation on the unit circle. Partial indices are defined and their uniqueness is proven. In previous works, the main research method for the study scalar singular integral operators and Riemann boundary value problems with Carlemann shift were operator identities, which allowed to eliminate shift and to reduce scalar problems to matrix problems without shift. In this study, the operator identities were used for the opposite purpose: to transform operators of multiplication by matrix-functions into scalar operators with Carlemann linear-fractional shift.展开更多
We continue studying systems whose state depends on time and whose resources are renewably based on functional operators with shift. In previous articles, we considered the term which described results of reproductive...We continue studying systems whose state depends on time and whose resources are renewably based on functional operators with shift. In previous articles, we considered the term which described results of reproductive processes as a linear expression or as a shift summand. In this work, the reproductive term is represented using an integral with a degenerate kernel. A cyclic model of evolution of the system with a renewable resource is developed. We propose a method for solving the balance equation and we determine an equilibrium state of the system. Having applied this model, we can investigate problems of natural systems and their resource production.展开更多
This paper is devoted to explanation of a phenomenon of current channels heads acceleration which bridges a discharge gap.This phenomenon was discovered experimentally during some works at investigating nanosecond str...This paper is devoted to explanation of a phenomenon of current channels heads acceleration which bridges a discharge gap.This phenomenon was discovered experimentally during some works at investigating nanosecond streamer gas discharges of atmospheric pressure in the air and neon.Consideration of the bridging process of the discharge gap is presented in the framework of a model of microstructured current channel.In this case,the channel represents itself as a bunch of microchannels(up to 1 000 and more).Such consideration could be stipulated by the discovered earlier phenomenon of the current channels microstructuring that are realized in the nanosecond discharges of atmospheric pressure.The authors have developed the electro-technical model of the discharge gap bridging by the conducting channel.It is shown that the channel length dependence of the velocity is linear;this is similar to that of the model of the continuous(unstructured)channel.We considered and made estimations that stipulate a possibility of gas heating in the microchannels up to the temperatures of associative ionization beginning in the discharge gap bridging phase.In this case,increase of the charged particles concentration and,consequently,decrease of its resistance cause the head acceleration.It is shown that in case of the continuous channel it is impossible to realize the gas heating up to the temperatures of the associative ionization in these conditions.Obtained results reveal the physical reason of the current channels microstructuring as a consequence of the principle of least action manifestation in the area electric breakdown phenomena of the gases.展开更多
In this paper, we consider functional operators with shift in weighted H?lder spaces. We present the main idea and the scheme of proof of the conditions of invertibility for these operators. As an application, we prop...In this paper, we consider functional operators with shift in weighted H?lder spaces. We present the main idea and the scheme of proof of the conditions of invertibility for these operators. As an application, we propose to use these results for solution of equations with shift which arise in the study of cyclic models for natural systems with renewable resources.展开更多
In this paper we consider operators with endpoint singularities generated by linear fractional Carleman shift in weighted Hölder spaces. Such operators play an important role in the study of algebras generate...In this paper we consider operators with endpoint singularities generated by linear fractional Carleman shift in weighted Hölder spaces. Such operators play an important role in the study of algebras generated by the operators of singular integration and multiplication by function. For the considered operators, we obtained more precise relations between norms of integral operators with local singularities in weighted Lebesgue spaces and norms in weighted Hölder spaces, making use of previously obtained general results. We prove the boundedness of operators with linear fractional singularities.展开更多
Coal is one of the most popular sources of energy. However, it has a relatively low energy efficiency due to high humidity and a greater release of harmful substances during combustion. On the other hand, the coal res...Coal is one of the most popular sources of energy. However, it has a relatively low energy efficiency due to high humidity and a greater release of harmful substances during combustion. On the other hand, the coal reserve on earth is estimated at 500 years and the cost is relatively low. This causes the search for new ways of processing coal. One way to efficiently process coal, while reducing the humidity and content of harmful components is microwave treatment. The basic information for microwave exposure to coal is the temperature field. In this paper, an approximate-analytically nonlinear mathematical model for heating a flat coal mass is studied, provided that the absorbed microwave energy is removing by heat radiation and convection simultaneously.展开更多
A new search for two-neutrino double-beta(2νββ)decay of^(136)Xe to the 0+1 excited state of 136Ba is performed with the full EXO-200 dataset.A deep learning-based convolutional neural network is used to discriminat...A new search for two-neutrino double-beta(2νββ)decay of^(136)Xe to the 0+1 excited state of 136Ba is performed with the full EXO-200 dataset.A deep learning-based convolutional neural network is used to discriminate signal from background events.Signal detection efficiency is increased relative to previous searches by EXO-200 by more than a factor of two.With the addition of the Phase II dataset taken with an upgraded detector,the median 90%confidence level half-life sensitivity of 2νββdecay to the 0+1 state of 136Ba is 2.9×10^(24)yr using a total^(136)Xe exposure of 234.1 kg yr.No statistically significant evidence for 2νββdecay to the 0^(+)_(1)state is observed,leading to a lower limit of T2ν1/2(0^(+)→0^(+)_(1))>1.4×10^(24)yr at 90%confidence level,improved by 70%relative to the current world's best constraint.展开更多
文摘The results of numerical analysis of turbine flow capacity and other parameters at different turbine rows are presented in this paper. Mass flow calculations by 3D Euler code has been controlled by means of 3D Navier-Stokes code taking into account inlet turbulence intensity and turbulence scale. The use of complicated numerical approaches (3D Euler or 3D Navier-Stokes codes) for mass flow definition demands close attention to quality of numerical techniques. Various reasons of inaccuracy of mass flow definition by using different 3D numerical approaches are analyzed.
文摘BACKGROUND Peritoneal metastasis(PM),arising from gastric cancer(GC),is the most common pattern of synchronous and metachronous dissemination and is generally associated with poor prognosis.New therapeutic modalities are being increasingly employed for such patients.AIM To develop more advanced methods,it becomes necessary to study the results of existing standard treatment methods in patients with PM in order to perform a comparative analysis of the strategies.METHODS A retrospective analysis of the efficiency of standard treatment methods(i.e.,palliative chemotherapy,palliative gastrectomy,and the best supportive care)was performed on 200 GC patients with synchronous PM.RESULTS The overall survival(OS)rate in 200 GC patients with PM under standard treatment was 5.4 mo.One-year survival occurred in 18.4%of patients.In multivariate analysis,the survival rate was significantly influenced by the following factors:Presence of extraperitoneal metastases,and stage of PM according to both the Japanese Gastric Cancer Association(JGCA)and the peritoneal cancer index(PCI).The median OS and 1-year survival of patients withР1,P2,and P3(JGCA)carcinomatosis were 9.8 mo,6.7 mo,and 4.0 mo,and 47.2%,18.8%,and 5.1%,respectively.The application of the palliative gastrectomy resulted in an increase in the median OS by up to 17 mo compared to the conservative approach where the value was 8.5 mo(P=0.05)in patients withР1РМ.In patients withР3,palliative chemotherapy increased the OS by up to 5.6 mo compared to the OS of 3.2 mo(P=0.0006)for best supportive care.The median OS and 1-year survival of patients withРCI of 1-6,7-12 and 13+points were 8.5 mo,4.2 mo,and 4.1 mo,and 39.8%,6.7%,and 5.5%,respectively.Palliative gastrectomy increased the median OS to 12.6 mo compared to conservative approach of 8.0 mo(P=0.03)in patients withРCI of 1-6 points.In patients withРCI 13+points,only palliative chemotherapy increased the OS to 6.0 mo compared to the OS of 3.4 mo for best supportive care(P=0.0008).CONCLUSION GC patients with PM are
文摘In this paper, we consider operators arising in the modeling of renewable systems with elements that can be in different states. These operators are functional operators with non-Carlemann shifts and they act in Holder spaces with weight. The main attention was paid to non-linear equations relating coefficients to operators with a shift. The solutions of these equations were used to reduce the operators under consideration to operators with shift, the invertibility conditions for which were found in previous articles of the authors. To construct the solution of the non-linear equation, we consider the coefficient factorization problem (the homogeneous equation with a zero right-hand side) and the jump problem (the non-homogeneous equation with a unit coefficient). The solution of the general equation is represented as a composition of the solutions to these two problems.
文摘Following the classical definition of factorization of matrix-functions, we introduce a definition of factorization for functional operators with involutive rotation on the unit circle. Partial indices are defined and their uniqueness is proven. In previous works, the main research method for the study scalar singular integral operators and Riemann boundary value problems with Carlemann shift were operator identities, which allowed to eliminate shift and to reduce scalar problems to matrix problems without shift. In this study, the operator identities were used for the opposite purpose: to transform operators of multiplication by matrix-functions into scalar operators with Carlemann linear-fractional shift.
文摘We continue studying systems whose state depends on time and whose resources are renewably based on functional operators with shift. In previous articles, we considered the term which described results of reproductive processes as a linear expression or as a shift summand. In this work, the reproductive term is represented using an integral with a degenerate kernel. A cyclic model of evolution of the system with a renewable resource is developed. We propose a method for solving the balance equation and we determine an equilibrium state of the system. Having applied this model, we can investigate problems of natural systems and their resource production.
文摘This paper is devoted to explanation of a phenomenon of current channels heads acceleration which bridges a discharge gap.This phenomenon was discovered experimentally during some works at investigating nanosecond streamer gas discharges of atmospheric pressure in the air and neon.Consideration of the bridging process of the discharge gap is presented in the framework of a model of microstructured current channel.In this case,the channel represents itself as a bunch of microchannels(up to 1 000 and more).Such consideration could be stipulated by the discovered earlier phenomenon of the current channels microstructuring that are realized in the nanosecond discharges of atmospheric pressure.The authors have developed the electro-technical model of the discharge gap bridging by the conducting channel.It is shown that the channel length dependence of the velocity is linear;this is similar to that of the model of the continuous(unstructured)channel.We considered and made estimations that stipulate a possibility of gas heating in the microchannels up to the temperatures of associative ionization beginning in the discharge gap bridging phase.In this case,increase of the charged particles concentration and,consequently,decrease of its resistance cause the head acceleration.It is shown that in case of the continuous channel it is impossible to realize the gas heating up to the temperatures of the associative ionization in these conditions.Obtained results reveal the physical reason of the current channels microstructuring as a consequence of the principle of least action manifestation in the area electric breakdown phenomena of the gases.
文摘In this paper, we consider functional operators with shift in weighted H?lder spaces. We present the main idea and the scheme of proof of the conditions of invertibility for these operators. As an application, we propose to use these results for solution of equations with shift which arise in the study of cyclic models for natural systems with renewable resources.
文摘In this paper we consider operators with endpoint singularities generated by linear fractional Carleman shift in weighted Hölder spaces. Such operators play an important role in the study of algebras generated by the operators of singular integration and multiplication by function. For the considered operators, we obtained more precise relations between norms of integral operators with local singularities in weighted Lebesgue spaces and norms in weighted Hölder spaces, making use of previously obtained general results. We prove the boundedness of operators with linear fractional singularities.
文摘Coal is one of the most popular sources of energy. However, it has a relatively low energy efficiency due to high humidity and a greater release of harmful substances during combustion. On the other hand, the coal reserve on earth is estimated at 500 years and the cost is relatively low. This causes the search for new ways of processing coal. One way to efficiently process coal, while reducing the humidity and content of harmful components is microwave treatment. The basic information for microwave exposure to coal is the temperature field. In this paper, an approximate-analytically nonlinear mathematical model for heating a flat coal mass is studied, provided that the absorbed microwave energy is removing by heat radiation and convection simultaneously.
文摘A new search for two-neutrino double-beta(2νββ)decay of^(136)Xe to the 0+1 excited state of 136Ba is performed with the full EXO-200 dataset.A deep learning-based convolutional neural network is used to discriminate signal from background events.Signal detection efficiency is increased relative to previous searches by EXO-200 by more than a factor of two.With the addition of the Phase II dataset taken with an upgraded detector,the median 90%confidence level half-life sensitivity of 2νββdecay to the 0+1 state of 136Ba is 2.9×10^(24)yr using a total^(136)Xe exposure of 234.1 kg yr.No statistically significant evidence for 2νββdecay to the 0^(+)_(1)state is observed,leading to a lower limit of T2ν1/2(0^(+)→0^(+)_(1))>1.4×10^(24)yr at 90%confidence level,improved by 70%relative to the current world's best constraint.
