Differential Equations

Article	Citations
Optimization Inverse Spectral Problem for a Vector Sturm–Liouville Operator	16
Application of Differential-Geometric Methods of Control Theory in the Theory of Partial Differential Equations. II	11
Linear Version of the Anti-Perron Effect of Change of Positive Characteristic Exponents to Negative Ones	11
On the Fundamental Solution of a Parabolic Equation with Dini Continuous Coefficients	11
Regularity of the Pressure Function for Weak Solutions of the Nonstationary Navier–Stokes Equations	10
Equivalence of Entropy and Renormalized Solutions of a Nonlinear Elliptic Problem in Musielak–Orlicz Spaces	10
Multistep Methods for Second-Order Differential-Algebraic Equations	10
On the Solvability of a Periodic Problem for a System of Ordinary Differential Equations with the Main Positive Homogeneous Nonlinearity	10
Probabilistic Interpretation of the Cauchy Problem for Systems of Nonlinear Parabolic Equations	9
Local Computational Algorithms for a System of First-Order Equations with Memory Effects	8
On the Construction of Difference Schemes for Calculating Viscous Gas Flows in Orthogonal Curvilinear Coordinates	8
Approximation of Multi-Region Inner Layer Solutions for Second-Order Weakly Nonlinear Singularly Perturbed Problems with Advance and Delay	8
Pseudodifferential Equations and Boundary Value Problems in a Multidimensional Cone	7
Poisson Formula for the Solution of the Radial Cauchy Problem for a Singular Ultrahyperbolic Equation	7
Equiconvergence Theorems for Spectral Expansions for Sturm–Liouville Operators on a Finite Interval with Potential Distributions	7
Solving a One-Dimensional Hypersingular Integral Equation Using Haar’s Wavelets	7
Dirichlet Problem for a Two-Dimensional Wave Equation in a Cylindrical Domain	7
The Existence of a Unique Fixed Point of Mappings Generated by a Multidimensional System with Relay Hysteresis	7
Initial Value Problem for a Third-Order Nonlinear Integro-Differential Equation of Convolution Type	7
Estimates of Solutions of Second-Order Linear Elliptic Inequalities	6
On the Blow-Up of the Solution of a Problem for the Sobolev Equation with a Noncoercive Source	6
On Linearization of Single-Input Nonlinear Control Systems Based on Time Scaling and a One-Fold Prolongation	6
Solvability of an Initial–Boundary Value Problem for the Modified Kelvin–Voigt Model with Memory along Fluid Motion Trajectories	6
Generalization of the Oblique Derivative Problem for the Helmholtz Equation in a Disk	6
On the Unique Solvability of Initial–Boundary Value Problems for Parabolic Systems in a Plane Bounded Domain with General Boundary Conditions	6

On the Stability of Solutions to Control Problems for a Nonlinear Reaction–Diffusion–Convection Model	6
On Constructing a Piecewise Affine Stabilizer for a Nonlinear System	6
Sufficient Hyperbolicity Conditions for Flows	6
Nonanalytic First Integrals of Analytic Systems of Differential Equations in a Neighborhood of Stable Equilibria	6
Boundary Value Problem for Stationary Magnetohydrodynamic Equations of Heat-Conducting Fluid with Variable Coefficients	6
Family of Logarithmic Spirals in Hamiltonian Systems of Dimension 8 with Control in a Disk	5
System without Characteristic Directions with a Nonanalytic Center Condition	5
Finite Stabilization Controllers for Hybrid Linear Continuous-Discrete Systems	5
Simultaneous Stabilization of a Family of Linear Dynamic Plants	5
Modelling the Dynamics of Social Protests: Mean-Field Games and Inverse Problems	5
On the Existence of Feedback Control for One Fractional Voigt Model	5
Classification of Field Equations for Weyl and Elko Spinors	5
Geometric Conservation Law for Finite Volume Discretization of the Stefan Problem on Boundary-Fitted Grids	5
On the Absence of Solutions of Differential Inequalities with the $$\infty $$-Laplacian	5
On the Solvability of Fredholm Boundary Integral Equations of the First Kind for the Three-Dimensional Transmission Problem on the Spectrum	5
Observability of Time-Varying Discrete Descriptor Systems	5
Well-Posed Solvability of Volterra Integro-Differential Equations Arising in Viscoelasticity Theory	4
Erratum to: On the Eighty-Fifth Anniversary of Viktor Antonovich Sadovnichii	4
Uniform Convergence of Spectral Expansions for a Problem with a Boundary Condition Depending on a Spectral Parameter	4
Ultimate Dynamics of a Cancer Model with Angiogenic Switch and Combined Therapy	4
On the Solvability of a System of Nonlinear Integral Equations with the Hammerstein–Stieltjes Operator on the Half-Line	4
Asymptotics of the Solution of Discrete-Time Linear-Quadratic Optimal Control Problems with Small Step and Weak Control in the Critical Case	4
High-Order Grid-Characteristic Method for Systems of Hyperbolic Equations with Piecewise Constant Coefficients	4
Identification of the Order of the Fractional Derivative in the Windkessel Model	4
Christoffel–Darboux Formula for Polynomial Eigenfunctions of Second-Order Linear Differential Equations	4
On the Existence of Countably Many Periodic Solutions of a Boundary Value Problem for the Beam Vibration Equation with Homogeneous Boundary Conditions	4
Finite Velocity of Propagation of Perturbations for a One-Dimensional Wave Integro-Differential Equation with a Fractional-Exponential Memory Function	4
On the Spectra of Oscillation Indices of a Two-Dimensional Nonlinear System and Its First Approximation System	4
On a Minimax Problem for the Spread of Trajectories of a Nonlinear Plant	4
Phragmén–Lindelöf Type Theorems	4
Invariants of Geodesic, Potential, and Dissipative Systems with Three Degrees of Freedom	4
Computation of the Leading Eigenvalue and the Corresponding Eigenelement of Eigenvalue Problems with Nonlinear Dependence on the Spectral Parameter	4
Stabilization of a Differential-Difference System of Delay Type	4
Explicit–Implicit Schemes for Calculating Dynamics of Elastoviscoplastic Media with Softening	4
The Cauchy Problem for a Nonlinear Wave Equation	4
Construction of Polynomial Eigenfunctions of a Second-Order Linear Differential Equation	4
Searching for Parameters of a Model with the Best Local Controllability	4
Stability Criterion and Sharp Estimates for the “Super-Twisting” Algorithm	4
A Numerical Method for the Optimization of the Diffraction Efficiency of Thin-Layer Coatings with Diffraction Gratings	4
Classification of Quasilinear Systems of Ordinary Differential Equations and Its Application to Normalization of Systems in the Bogdanov–Takens Critical Case	4
Application of a Generalized Fixed Point Principle to the Study of a System of Nonlinear Integral Equations Arising in the Population Dynamics Model	4
On a Control Problem for a System of Implicit Differential Equations	3
Approximate Solution of the Inverse Boundary Value Problem for a Singularly Perturbed System of Partial Differential Equations	3
On Systems of Differential Equations with Constraints in the Form of Not Necessarily Convex Sets	3
On Error Estimates for Discretization Operators for the Solution of the Poisson Equation	3
Model First Boundary Value Problem for a Parabolic System in Zygmund Spaces	3
Classical Solution of the First Mixed Problem for the Wave Equation in Cylindrical Domain in Odd-Dimensional Space	3
Applying Differential-Geometric Control Theory Methods in the Theory of Partial Differential Equations. III	3
Conservative Compact and Monotone Fourth-Order Difference Schemes for One- and Two-Dimensional Quasilinear Equations	3
On a Nonclassical Eigenvalue Problem with Nonlinearizable Solutions	3

Methods for Parametric Identification of Fractional Differential Equations	3
On Multidimensional Exact Solutions of the Generalized Monge–Ampère Evolution Equations	3
Integration of the Negative-Order Modified Korteweg–de Vries Equation with a Loaded Term in the Class of Periodic Functions	3
Construction of the Transfer Function of the Poincaré–Steklov Operator for an Elastic Layer	3
On Sufficient Conditions for Optimality in the Weight Minimization Problem for a Shell of Revolution at a Given Vibration Frequency	3
Conservative Equations in Field Theory: Conservation and Symmetry Laws	3
Numerical Solution of Integral Equations of the Third Kind with Fixed Singularities of the Kernel	3
On the Existence of Periodic Solutions of a System of Second-Order Ordinary Differential Equations with a Quasihomogeneous Nonlinearity	3
On the Study of Robust Exponential Stability of Continuous- and Discrete-Time Systems	3
On Instability in Systems with an Integral Invariant	3
Fredholm Integral Equation for Problems of Acoustic Scattering by Three-Dimensional Transparent Structures	3
Front Motion in a Reaction–Diffusion–Advection Problem with a KPZ-Nonlinearity	3
A Difference Scheme with Well-Controlled Dissipation for Solving the Kapila Model Equations	3
Spectral Properties of the Generator of a Semigroup Generated by the Volterra Integro-Differential Equation	3
An Inverse Problem for Electrodynamic Equations with a Nonlinear Dependence of the Current Density on the Electric Field	3
On the Realization of Finite Essential Spectra of Oscillation Exponents of Two-Dimensional Differential Systems	3
Theoretical Aspects of Constructing a Neurocontroller for Switched Systems	3
Variational Methods for Solving Problems Associated with Artificial Intelligence	3
Stability Change of Invariant Manifolds of Differential Systems with Multiscale Variables	3
On the Solvability of Linear Differential Operators on Vector Bundles over a Manifold	3
Existence of an Anti-Perron Effect of Change of Positive Exponents of the Linear Approximation System to Negative Ones under Perturbations of a Higher Order of Smallness	3
Maximum Principle in the Linear Optimal-Time Control Problem	3
On the Weak Solvability of a Mathematical Model Describing the Motion of Polymer Solutions with Memory	3
Initial–Boundary Value Problem for Flows of a Fluid with Memory in a 3D Network-Like Domain	3
On Feedback Control Systems Governed by Fractional Differential Inclusions	3
On the Fundamental Solution Matrix of the Plane Anisotropic Elasticity Theory	3
Explicit Formulas for the Coefficients in the Lappo-Danilevsky Solution of Linear Ordinary Differential Equations	3
Holomorphic Regularization of Singularly Perturbed Integro-Differential Equations	3
Stable Solution of Tracking and Dynamic Reconstruction Problems under Measuring State Coordinates at Discrete Times	2
On the Properties of Oscillation Indices of Solutions to Differential Systems	2
To the Solution of the Inverse Problem of Scattering Theory on the Entire Line	2
Globally Stable Difference Schemes for the Fisher Equation	2
Asymptotic Analysis of a Class of Higher-Order Quasilinear Singular Perturbation Boundary Value Problems with the Same Type of Singularity	2
Sliding Window Algorithm for Parametric Identification of Dynamical Systems with Rectangular and Ellipsoid Parameter Uncertainty Domains	2
On the Wandering Velocity of Solutions to Linear Autonomous Differential Systems	2
Asymptotic Solution for Three-Dimensional Reaction–Diffusion–Advection Equation with Periodic Boundary Conditions	2
On the Relationship Between the Pontryagin Maximum Principle and the Hamilton–Jacobi–Bellman Equation in Optimal Control Problems for Fractional-Order Systems	2
Solution of Some Problems for the String Vibration Equation in a Half-Strip by Quadratures	2
Sub-Lorentzian Extremals Defined by an Antinorm	2
On the Asymptotics of Solutions of Ordinary Differential Equations of Odd Order	2
On the Unique Solvability of Initial–Boundary Value Problems for Parabolic Systems in Bounded Plane Domains with Nonsmooth Lateral Boundaries	2
Distribution of the Spectrum of a Sturm–Liouville Operator Perturbed by a Delta Interaction	2
Singular and Fixed Points of a Mapping Generated by a Multidimensional System of Ordinary Differential Equations with Relay Hysteresis	2
Tricomi Problem for a Differential–Difference Equation of Mixed Type with Parallel Degeneration Lines	2
Modification of the Discrete Singularity Method for Nonuniform Grids As Applied to One-Dimensional Integral Equations with a Strong Singularity in the Kernel	2
Boundary Value Problem for an Inhomogeneous Fourth-Order Equation with Lower-Order Terms	2
Finite Stabilization of Incompletely Controllable Hybrid Linear Continuous-Discrete Systems	2
Optimal Feedback in a Linear–Quadratic Optimal Control Problem for a Fractional-Order System	2
Finite Stabilization Based on Incomplete Measurements for not Completely Controlled Systems of Neutral Type	2
Stabilization of a Switched System with Commensurate Delays under Slow Switchings	2
On the Monotonicity of Solutions of Nonlinear Systems with Respect to the Initial Conditions	2
On Singular Heat Equation	2
Green’s Function of a Sturm Type Boundary Value Problem for a Fractional Delay Differential Equation	2
On a Class of Periodic $$E $$-Functions	2
On Some Properties of the Shift on an Infinite-Dimensional Torus	2
On Singularities of $$A $$-Orbital Feedback Linearization of Single-Input Affine Controllable Systems	2
Traveling Wave Method	2
Local Bifurcations in Continuous-Discrete-Time Two-Parameter Dynamical Systems	2
The Neumann Problem in a Domain with Transverse Perforation	2
Existence of Solutions of a Boundary Value Problem for a Diffusion Equation with Piecewise Constant Arguments	2
The Cauchy Problem for a Nonlinear Hirota-Type Equation with a Self-Consistent Series Source	2
Reflecting Function and a Generalization of the Notion of First Integral	2
Finite-Difference Integro-Interpolation Method for Discontinuous Solutions of the Usadel Equations	2
Partial Stability of Systems of Itô Linear Delay Differential Equations	2
Properties of Degenerate Systems of Linear Integro-Differential Equations and Initial Value Problems for These Equations	2
Operator Methods for Investigating Stability and Bifurcation Problems in a Reaction–Diffusion System and Applications	2
Sharp Observation Error Estimate for the “Super-Twisting” Algorithm in the Presence of Measurement Error	2
Blow-Up of the Solution and Global Solvability of the Cauchy Problem for the Equation of Vibrations of a Hollow Rod	2
To the Analysis of Nonlocal Problems of the Theory of Nonlinear Differential Systems	2
Problem on the Optimal Estimation of the Initial State of a Linear Singularly Perturbed System	2
Localization of Eigenfunctions of the Dirichlet Problem near a Contour at the Boundary of a Thin Domain	2
Mathematical Modeling of the Motion of Metal Conductors in an Electromagnetic Field with Regard to the Presence of Different Phases of the Matter Being Accelerated	2
Construction of Diagonal Lyapunov–Krasovskii Functionals for a Class of Positive Differential-Algebraic Systems	2
Solvability of a Boundary Value Problem for the Stationary Heat and Mass Transfer Equations with Variable Coefficients	2
Finite Stabilization and Finite Spectrum Assignment by a Single Controller Based on Incomplete Measurements for Linear Systems of the Neutral Type	2
Representation of the Green’s Function of the Navier Problem for the Biharmonic Equation in a Ball	2
Group Analysis, Reductions, and Exact Solutions of the Monge–Ampère Equation in Magnetic Hydrodynamics	2
A Finite-Difference Scheme for Discontinuous Solutions of the Usadel Equations	2
Balance-Characteristic Method for Calculating Hemodynamics of a Single Vessel	2
Group Analysis and Exact Solutions of a Geophysical Hydrodynamics Equation with Monge–Ampère Type Nonlinearity	2

Quantitative Controllability Indices of Nonlinear Systems	2
Well-Posedness of the Generalized Samarskii–Ionkin Problem for Elliptic Equations in a Cylindrical Domain	2
Dirichlet Problem on the Half-Line for an Abstract Euler–Poisson–Darboux Equation Containing Powers of an Unbounded Operator	2
On Asymptotics of the Spectrum of an Integral Operator with a Logarithmic Kernel of a Special Form	2
Asymptotic Behavior of the Solution to the Cauchy Problem for a Nonlinear Equation	2
Solution of a Problem with Initial Conditions of the Cauchy Type for a Higher-Order Equation with a Hilfer Fractional Derivative	2
Nonideal Thermal Contact Problem	2
On the Spectrum of Nonself-Adjoint Dirac Operators with Two-Point Boundary Conditions	2
On the Existence of Solutions of Degenerate Discrete-Time Systems	2
On the Numerical Solution of Nonconservative Hyperbolic Systems of Equations	2
Averaging in a Neumann Sieve-Type Domain with “Light” Concentrated Masses. Subcritical Case	1
On the Variation of the Nonlinearity Parameter in the “Super-Twisting” Algorithm	1
On One Cauchy Problem for a Hyperbolic Differential-Difference Equation	1
On the Stability by the Nonlinear Nonstationary Hybrid Approximation	1
Stability of Fixed Points in Ordered Spaces. Applications to Boundary Value Problems for Hopfield-Type Equations of a Neural Network	1
On an Elliptic Problem in a Half-Plane with a Cut along a Ray	1
Classical Solutions of Hyperbolic Equations with Translation Operators in Lower-Order Derivatives	1
Instability and Stabilization of Solutions of a Stochastic Model of Viscoelastic Fluid Dynamics	1
Two-Dimensional Boundary Value Problems for Filtration Flows with Randomly Located Sources in an Inhomogeneous Porous Layer	1
Finding the Two-Dimensional Relaxation Kernel of an Integro-Differential Wave Equation	1
On the Lower Bound of the Hypersingular Operator in Peridynamics Problems	1
On a Nonlinear Second-Order Ordinary Differential Equation	1
On a Class of Control Problems with Mixed Constraints	1
Integral Equations of Volterra Typewith Two Boundary and One Interior Singular Point	1
Correctness Analysis of a Boundary Value Problem for Stationary Magnetohydrodynamics Equations with Variable Coefficients	1
Smooth Solutions of Hyperbolic Equations with Translation by an Arbitrary Vector in the Free Term	1
Study of the Parameter Space of a Multidimensional System with Relay Hysteresis and Perturbation	1
Minimum Principle for the Tikhonov Functional in the Problem of Stable Continuation of a Potential Field from a Surface	1
Reconstruction of Disturbances in a System of Differential Equations with Inaccurate Measurement of Part of the Coordinates	1
On the Features of Numerical Solution of Coefficient Inverse Problems for Nonlinear Equations of the Reaction–Diffusion–Advection Type with Data of Various Types	1
Initial–Boundary Value Problem for a Nonlinear Modified Boussinesq Equation	1
On A.P. Favorskii’s Quasiacoustic Scheme	1
On the Fredholm Property and Solvability of a System of Integral Equations in the Transmission Problem for the Helmholtz Equation	1
Asymptotic Properties of Parametric Eigenvalue Problems in a Hilbert space	1
A Numerical Method for Solving the Diffraction Problem Described by Maxwell’s Equations with Mesoscopic Boundary Conditions	1
Stabilization of a Switched Interval System with Commensurate Delays under Slow Switchings	1
Solution of the Cauchy Problem for One Degenerate Equation with the Dzhrbashyan–Nersesyan Fractional Derivative	1
Invariant Manifolds and Global Attractor of the Ginzburg–Landau Integro-Differential Equation	1
Spectrum Assignment for a System of Neutral Type	1
A Note on Simple Wave Solution for Magnetohydrodynamic System with General Equation of State	1
On a Property of a Biharmonic Function in an Unbounded Domain in $$\mathbb {R}^3$$	1
On Asymptotic Behavior of Solutions of Linear Inhomogeneous Stochastic Differential Equations with Correlated Inputs	1
Asymptotics of the Spectrum for a Fourth-Order Differential Operator with a Spectral Parameter in Two Boundary Conditions	1
A Special Version of the Collocation Method for One Class of Integro-Differential Equations	1
On the Exact Controllability of a Semilinear Evolution Equation with an Unbounded Operator	1
On the Solvability of Incomplete Problems for an Abstract Singular Equation	1
An Inverse Problem for the Wave Equation with Two Nonlinear Terms	1
Bifurcations in Integrable Hamiltonian Systems near Corank-One Singularities	1
Spectral Analysis of 1D Dirac System with Summable Potential and Sturm–Liouville Operator with Distribution Coefficients	1
On the Stabilization of Time Averages of the Solution to a Petrovskii-Parabolic System of Equations	1
On an Analog of the Ambarzumian Theorem	1
Boundary Value Problem for One Differential Equation with Variable Coefficients and Liouville Fractional Derivative	1
Classical Solution to a Mixed Problem with the Dirichlet and Wentzel Conditions for the Biwave Equation with Nonlinear Lower Terms	1
Two-Dimensional Asymptotic Models of Thin Cylindrical Elastic Gaskets	1
On the Properties of a Dirac Operator with Irregular Boundary Conditions	1
On the Existence of a Globally Lyapunov Unstable Differential System All of Whose Solutions Tend to Zero as Time Tends to Infinity	1
Multiplicative Control Problems for the Diffusion–Drift Charging Model of an Inhomogeneous Polar Dielectric	1
Construction of Integral Representations of Fields in Problems of Diffraction by Penetrable Bodies of Revolution	1
On One Gellerstedt Problem with Data on Parallel Characteristics	1
Upper Estimates of the Perturbation Growth under Triaxial Spreading–Drain in Infinite Viscous Space	1
Some Variational Principles for Self-Adjoint Hamiltonian Systems	1
Approximation to the Sturm–Liouville Problem with a Discontinuous Nonlinearity	1
On the Leading Term of the Spectral Asymptotics for the Zaremba–Steklov Operator in a Bounded Domain	1
Weighted Hardy–Littlewood Spaces in Piecewise Smooth Domains	1
Solvability of Linear Differential Equations	1
Control Problems for Fractional-Order Systems: Formalism of Hamilton–Jacobi Equations and Methods for Constructing Optimal Feedback Strategies	1
Sufficient Condition for the Consistency of a Piecewise Linear Approximation to a Nolinear Affine System	1
On Some Extremal Problems Associated with Motion in a Velocity Field	1
On the Asymptotic Stability and Ultimate Boundedness of Solutions of a Class of Nonlinear Systems with Delay	1
Solvability of a System of Nonlinear Integral Equations with Piecewise Constant Kernels	1
On the Dynamic Tension of a Thin Round Perfectly Rigid-Plastic Layer Made of Transversely Isotropic Material	1
Estimates of Integrally Bounded Solutions of Linear Differential Inequalities	1
Representation of the Green’s Function of the Dirichlet Problem for the Polyharmonic Equation in the Ball	1
Distribution of Spectrum of the Weber Operator Perturbed by the Dirac Delta Function	1
A Nonlocal Problem with an Integral Matching Condition for a Loaded Parabolic-Hyperbolic Equation with a Fractional Caputo Derivative	1
On the Main Properties of Solution Sets of Ordinary Differential Equations	1
Asymptotics of the Solution of a Singularly Perturbed System of Equations with a Single-Scale Internal Layer	1
Internal Transition Layer Structure in the Reaction–Diffusion Problem for the Case of a Balanced Reaction with a Weak Discontinuity	1
Triaxial Stabilization of a Rigid Body via a Delayed Feedback Law	1
Boundary Value Problem for a First-Order Partial Differential Equation with Liouville Fractional Derivative	1
Naimark Problem for an Ordinary Differential Equation with a Fractional Discrete Distributed Differentiation Operator	1
On the Pinsky Phenomenon for B-Elliptic Operators	1
Approximation of the Solution of an Inverse Problem for a Singularly Perturbed System of Partial Differential Equations	1
On the Properties of Solutions to Equations Arising While Modeling Cryochemical Synthesis of Pharmaceutical Nanoforms	1
On the Existence of Solutions of Nonlinear Boundary Value Problems for a System of Differential Equilibrium Equations for Timoshenko-Type Shells in Isometric Coordinates	1
Solution of a Semi-Boundary Value Problem for a Degenerate Partial Differential Equation	1
Existence and Stability of Solutions with Internal Transition Layer for the Reaction–Diffusion–Advection Equation with a KPZ-Nonlinearity	1
Algorithms for Robust Inversion of Dynamical Systems	1
A Priori Estimate of Solutions of a Mixed Problem for the Vlasov–Poisson System with a Homogeneous External Magnetic Field	1
Application of Differential-Geometric Methods of Control Theory to the Theory of Partial Differential Equations. IV	1
Retraction Note: Proof of the Jacobian Conjecture in the Two-Dimensional Case and Global Isochronous Centers of Polynomial Hamiltonian Differential Systems	1
Criterion for the Solvability of the Cauchy Problem for the Biharmonic Equation in $$\mathbb {R}^3$$ and Analytic Continuation of the Solution	1
Numerical Investigations of the Dynamics of Development of Two-Dimensional Perturbations in Magnetic Galathea Traps	1
On Determining the Coefficients of a Quadratic Lyapunov Function with Given Properties in the Case of Multiple Roots of the Characteristic Equation	1
Boundary Value Problem of Two-Dimensional Filtration of a Liquid in an Inhomogeneous Layer with a Boundary Condition Having Discontinuity of the First Kind	1