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A new class of energy dissipative, mass conserving and positivity/bound-preserving schemes for Keller-Segel equations

T0 review · 4 major / 5 minor · reviewed 2026-08-12 · deepseek-v4-flash

Pith's one-line read A predictor-corrector construction yields Keller-Segel schemes that preserve positivity or bounds, conserve mass, and dissipate a discrete energy while solving only linear Poisson-like equations.

desk verdict The energy-correction step is a genuinely useful new idea and the paper is mostly sound, but the missing proof of Theorem 3.2 and the unquantified σ-regularized energy are real gaps that need fixing before the dissipation claim is fully trustworthy. read the letter →

arxiv 2411.13067 v1 pith:HBB62CLY submitted 2024-11-20 math.NA cs.NA

classification math.NAcs.NA MSC 65M7065M1565N2265N12
keywords Keller-Segelequationspositivity-preservingbound-preservingenergydissipationmassconservationLagrangemultiplierpredictor-correctorCrank-Nicolson
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

The paper tries to establish that chemotaxis (Keller-Segel) simulations can be built from a predictor-corrector construction that preserves the physical constraints—nonnegative density, or density between 0 and a maximum M, conserved total mass, and a monotonically decreasing discrete free energy—while each time step only costs the solution of a few linear Poisson-like equations. The construction splits the constrained time step into three parts: an implicit-explicit predictor, a correction step that projects the density onto the feasible set via KKT-conditions, and an energy correction step that adds a scalar variable to enforce energy dissipation. This is done for two Keller-Segel systems, for first- through fifth-order BDF time discretizations and for Crank-Nicolson, with uniqueness, mass conservation, positivity/bound preservation, and energy dissipation proved for each family. For the second-order Crank-Nicolson bound-preserving scheme the paper also proves an error estimate of order $\delta t^4 + N^{4-2l}$ in the natural norms. A reader should care because positivity and energy stability are exactly the properties that keep numerical blow-up from being a numerical artifact in chemotaxis models.

What carries the argument

The central mechanism is a three-step operator split. First, an IMEX predictor solves linear equations for provisional variables. Second, a correction step enforces the KKT conditions $\lambda \ge 0$, $\rho \ge 0$, $\lambda\rho = 0$ (or $g(\rho) \ge 0$, $\lambda \ge 0$, $\lambda g(\rho) = 0$ for bounds), together with mass conservation $[\rho^{n+1},1]=[\rho^0,1]$, which the paper shows is equivalent to a convex $L^2$ projection and is uniquely solvable. Third, an energy correction step adds a scalar variable $\eta$ so that the discrete energy decreases by exactly the prescribed dissipation term. The key identities are the predictor-corrector relation $\rho^{n+1}-\tilde\rho^{n+1} = \frac{\delta t}{2}(\lambda^{n+1}+\xi^{n+1}-\lambda^n-\xi^n)$ (CN case) and the mass-conservation fact $[\rho^{n+1},1] \ne 0$, which makes the correction for $\eta$ a single linear equation. This decoupling is what keeps each substep cheap and lets the error analysis go through with standard estimates.

What would settle it

For a smooth manufactured solution of (1.4)-(1.6), run the Crank-Nicolson bound-preserving scheme (3.14)-(3.20) with a large number of collocation points and successively halved time steps; if the left-hand side of (5.10) does not decrease by a factor close to 16 when $\delta t$ is halved, the claimed $O(\delta t^4)$ error bound fails, and if any collocation value of $\rho$ leaves $[0,M]$, the bound-preserving claim fails.

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Extended reading notes

Core claim

The paper's central claim is that the four scheme families (2.9)-(2.15), (2.35)-(2.40), (3.3)-(3.8), and (3.14)-(3.20) are uniquely solvable, conserve mass, preserve positivity or bounds, and satisfy an exact discrete energy dissipation law, with stability theorems for BDF2 and Crank-Nicolson versions under the stated conditions. The second-order Crank-Nicolson bound-preserving scheme satisfies the error estimate (5.10): $$\|\rho(t_m)-\rho^m\|^2 + \frac{\delta $t^{2}$}{4}\|\$\lambda$^m g'(\rho^m)+\xi^m\|^2 + \|\nabla(c(t_m)-c^m)\|^2 + \frac{\delta t}{4}\sum_{n=0}^{m-1}\|\$\Delta$(c(t_{n+1})-$c^{{n+1}}$)+\$\Delta$(c(t_n)-c^n)\|^2 \lesssim \delta $t^{4}$ + $N^{{4-2l}}$.$$ If these theorems are correct, chemotaxis simulations can have positivity/bounds, mass conservation, and energy stability simultaneously at essentially the cost of a generic semi-implicit scheme.

Load-bearing premise

The load-bearing premise is that the discrete energy with the $\sigma$-regularized logarithms in (2.16) and (3.9) is a faithful stand-in for the physical free energy: $\sigma$ is only called a small positive number, and the paper does not prove how the two energies relate or what happens as $\sigma \to 0$.

Editorial extensions

If this is right

  • The same template can be applied with BDF1 through BDF5 or Crank-Nicolson time stepping and any spatial discretization with positive quadrature weights and nodal basis functions, with each step costing about as much as a generic semi-implicit linear solve.
  • For the type-I (classical) Keller-Segel system, the BDF2 and Crank-Nicolson positivity-preserving schemes are stable in 2D under the explicit small-data conditions (4.1) and (4.30), giving control on the density, gradient of the chemoattractant, and Lagrange multipliers.
  • For the type-II system with logistic sensitivity, the bound-preserving BDF2 and Crank-Nicolson schemes are unconditionally stable, with the density confined to $[0,M]$ and the energy and multiplier norms bounded by data and $M$.
  • The Crank-Nicolson bound-preserving scheme has the convergence rate $O(\delta t^4 + N^{4-2l})$ in the squared norm measuring density, multiplier combination, gradient of $c$, and cumulative $\Delta c$ errors (5.10).
  • Numerical experiments confirm the designed convergence orders, exact positivity/bounds at collocation points, and the ability of the positivity-preserving scheme to simulate the sharpening and blow-up profile of the classical Keller-Segel density.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • The same predictor-corrector-energy-correction decomposition should transfer to other positivity- or bound-constrained gradient-flow equations (for instance Poisson-Nernst-Planck or phase-field models with logarithmic potentials); this is an extension the paper does not make.
  • Because the energy dissipation is proved only for the $\sigma$-regularized entropy, a natural test is to run the scheme with $\sigma = 10^{-k}$ for decreasing $k$ and monitor the gap between the discrete energy in (2.16)/(3.9) and the physical energy (2.2)/(2.3); a growing gap would show the dissipation law does not track the physical free energy.
  • The stability theory for the positivity-preserving type-I schemes requires a small-data condition, whereas the bound-preserving type-II schemes do not; closing this gap would require a different Lyapunov functional or a maximum principle for the chemoattractant.
  • The error analysis covers only the Crank-Nicolson bound-preserving scheme with a spectral discretization; extending the same biased-error argument to the BDFk positivity-preserving family would test whether the $O(\delta t^4 + N^{4-2l})$ rate persists for higher-order time stepping.
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Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

4 major / 5 minor

Summary. The manuscript proposes predictor-corrector and energy-correction schemes for two Keller-Segel systems. In the predictor stage, standard IMEX/BDF or Crank-Nicolson updates are computed; in the correction stage, a Lagrange-multiplier step enforces positivity or the bound 0≤ρ≤M and mass conservation; a final scalar energy-correction step enforces a discrete energy law for a σ-regularized entropy. The authors claim unique solvability, mass conservation, positivity/bound preservation, exact discrete energy dissipation, stability under small data (type I) or unconditionally (type II), and a second-order error estimate for the bound-preserving Crank-Nicolson scheme, and they support these claims with numerical experiments.

Significance. The algorithmic construction is attractive: it reduces structure preservation to linear solves plus local projections and is formulated for general Galerkin-type spatial discretizations. The paper also provides a full convergence analysis and extensive two-dimensional experiments, including a blow-up study and a comparison with a generic scheme. If the proof gaps are repaired, the predictor-corrector energy-correction framework would be a useful contribution to structure-preserving discretizations of Keller-Segel systems. At present, however, several load-bearing estimates are not correct as written, and the proof of a central uniqueness/dissipation theorem is omitted.

major comments (4)
  1. [Section 4.1, Eq. (4.2); Section 4.2, Eq. (4.32); Section 4.3, Eq. (4.48)] The sign of the diffusion term after integration by parts is wrong. With the stated discrete inner product, [Δu,u] = -∥∇u∥², so the left-hand sides of (4.2), (4.32), and (4.48) should contain -4δt∥∇ρ̃^{n+1}∥², -2δt∥∇ρ̃^{n+1/2}∥², and -4δt∥∇ρ̃^{n+1}∥², respectively, rather than the corresponding positive terms. As written, the diffusion is turned into a source term, and the small-data stability bounds (4.24), (4.42), and (4.69) do not follow. This error is load-bearing for Theorems 4.2, 4.3, and 4.4.
  2. [Section 4.4, Eqs. (4.75)-(4.82)] The proof of Theorem 4.5 contains a dimensional inconsistency: the term δt∥∇ρ̃^{n+1/2}∥ in (4.75) and (4.78) should be δt∥∇ρ̃^{n+1/2}∥², and the same linear gradient term is propagated through (4.79), (4.81), and (4.82). Consequently the argument only controls a linear gradient norm rather than an H1-type energy, so the stability estimate (4.70) is not established. In addition, the BDF2 identity used in (4.17) is missing the expected factor 2; the identity should be re-derived before the terms are summed.
  3. [Section 3.2, Theorem 3.2] Theorem 3.2 is stated without proof ('we omit the proof here'), but it underlies the unique solvability, bound preservation, and energy dissipation of the bound-preserving Crank-Nicolson scheme (3.14)-(3.20). Unlike the positivity projection in Theorem 2.2, Step 3 in (3.16) involves the state-dependent coefficient g'(ρ^{n+1}) = M - 2ρ^{n+1} inside the complementarity condition, and the claimed equivalence with the convex minimization problem (3.13) is not automatic. A proof or a precise KKT argument for the nonlinear complementarity step is needed; without it, the central claim for this scheme rests on an assertion.
  4. [Sections 2.2, 2.3, and 3.1, Eqs. (2.15)-(2.16), (2.40)-(2.41), (3.8)-(3.9)] The discrete energy dissipation is proved for the σ-regularized energy E_σ, but σ is only described as 'a small positive number'. No theorem relates E_σ to the physical free energies (2.2)/(2.3) or (3.2), and the limit σ→0 is not analyzed. Since the energy-correction step enforces exact dissipation of E_σ, the claimed connection to the continuous energy-dissipation law (2.4)/(2.5) is not quantified, and a fixed positive σ could dissipate an energy far from the physically relevant one.
minor comments (5)
  1. [Section 2.3, Eq. (2.43)] The definition of C2 is printed as C2(u^n) = 2u^n - u^n; it should be C2(u^n) = 2u^n - u^{n-1}.
  2. [Section 4.2, proof of Theorem 4.3] The text 'Taking inner product of (4.75) with itself' should refer to Eq. (4.33), and the later reference to '(4.27)' should refer to the corresponding estimate in this section; the cross-references currently point to equations from Section 4.4.
  3. [Section 4.2, Eq. (4.42)] The statement of the Gronwall consequence uses m+1 on the left and m in the theorem statement; the index should be made consistent.
  4. [Section 6, Fig. 4 caption] The caption says 'second-order bound-preserving scheme (2.35)-(2.38)', but (2.35)-(2.38) is the positivity-preserving BDF2 scheme; the caption should refer to the bound-preserving scheme (3.3)-(3.8) or (3.14)-(3.20).
  5. [Section 7] 'feathure' should be 'feature'.

Circularity Check

0 steps flagged · score 2.0 of 10

No load-bearing circularity; the discrete energy law is imposed by the scheme construction, while solvability, stability, and error estimates are proved independently.

full rationale

The energy-dissipation identities (2.22), (2.47), (3.11), and (3.22) are exactly the energy-correction equations (2.15), (2.40), (3.8), and (3.20) written into the scheme, so the property is enforced by design rather than derived from a hidden prior result. This is a transparent construction feature, not a circular prediction. The substantive claims—unique solvability of the correction step by convex minimization (Theorems 2.2 and 2.5), mass conservation, positivity/bound preservation, the stability estimates of Section 4, and the error estimate (5.10)—are derived directly from the algebraic structure of the scheme and standard inequalities, without importing a uniqueness theorem from the authors' earlier papers. The self-citations [10,11] provide background for the Lagrange-multiplier formulation but are not the load-bearing step in any theorem. Two rigor gaps should be noted, though neither is circular: Theorem 3.2 is stated without proof ('Since the proof is similar to ... we omit the proof here'), and its CN bound-correction step is nonlinear, so the error analysis in Section 5 rests on an unverified premise; and the sigma-regularized energy (2.16)/(3.9) leaves the limit sigma -> 0 unquantified. These are correctness concerns, not cases where an output is equivalent to an input by construction.

Assumptions & free parameters 1 free parameters · 7 assumptions · 0 invented entities

The scheme relies on standard numerical analysis tools (projection theory, Ladyzhenskaya, Gronwall, spectral interpolation) and on the physical initial-mass assumption. No new physical entities are introduced; λ, ξ, η are mathematical Lagrange multipliers.

free parameters (1)
  • sigma (σ) = not specified
    Regularization parameter in the entropy terms of the discrete energies (2.16) and (3.9). It is introduced ad hoc to keep log arguments positive when ρ=0 or ρ=M; no value or error dependence is given in the paper.
assumptions (7)
  • domain assumption The discrete inner product is defined with positive quadrature weights β_z and a nodal basis, so that nodal values are well-defined (Section 2.1).
    Required to identify functions with their nodal values and to make the mass/positivity constraints meaningful. Violated by some non-Lagrangian discretizations.
  • standard math The correction step is exactly the L2 projection onto the convex feasible set, and KKT conditions describe its solution (Eqs. (2.23)-(2.24), (3.12)-(3.13)).
    Standard convex optimization; relies on Slater's condition and strict convexity.
  • standard math Ladyzhenskaya inequality ∥u∥_{L^4}^2 ≤ 2∥u∥_{L^2}∥∇u∥_{L^2} in 2D (Eq. (4.16)).
    Used in stability proofs for positivity-preserving schemes.
  • standard math Discrete Gronwall lemma (Lemma 4.1) with the stated assumptions.
    Used to close all stability and error estimates.
  • standard math Spectral interpolation error estimates (5.1) and positivity of interpolation at collocation points (5.2).
    Standard results for Legendre-Gauss-Lobatto interpolation.
  • domain assumption The exact solution regularity assumptions in Theorem 5.1.
    Needed for the spatial approximation and Taylor remainder bounds in the error analysis.
  • domain assumption Total initial mass [ρ0_h,1] ≠ 0.
    Ensures the denominator in (2.30)/(2.51) is nonzero and η is uniquely determined.

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Cite this review

Pith. "Pith review of A new class of energy dissipative, mass conserving and positivity/bound-preserving schemes for Keller-Segel equations." pith.science (2026). https://pith.science/paper/HBB62CLY

@misc{pith2026241113067,
  author       = {Pith},
  title        = {Pith review of: A new class of energy dissipative, mass conserving and positivity/bound-preserving schemes for Keller-Segel equations},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/HBB62CLY}},
  note         = {Machine review of arXiv:2411.13067}
}
read the original abstract

In this paper, we improve the original Lagrange multiplier approach \cite{ChSh22,ChSh_II22} and introduce a new energy correction approach to construct a class of robust, positivity/bound-preserving, mass conserving and energy dissipative schemes for Keller-Segel equations which only need to solve several linear Poisson like equations. To be more specific, we use a predictor-corrector approach to construct a class of positivity/bound-preserving and mass conserving schemes which can be implemented with negligible cost. Then a energy correction step is introduced to construct schemes which are also energy dissipative, in addition to positivity/bound-preserving and mass conserving. This new approach is not restricted to any particular spatial discretization and can be combined with various time discretization to achieve high-order accuracy in time. We show stability results for mass-conservative, positivity/bound-preserving and energy dissipative schemes for two different Keller-Segel systems. A error analysis is presented for a second-order, bound-preserving, mass-conserving and energy dissipative scheme for the second-type of Keller-Segel equations. Ample numerical experiments are shown to validate the stability and accuracy of our approach.

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Works this paper leans on

39 extracted references · 37 canonical work pages · cited by 1 Pith paper

  1. [1]

    Toward a mathematical theory of Keller–Segel models of pattern formation in biological tissues

    Nicola Bellomo, Abdelghani Bellouquid, Youshan Tao, and Michael Winkler. Toward a mathematical theory of Keller–Segel models of pattern formation in biological tissues. Mathematical Models and Methods in Applied Sciences, 25(09):1663–1763, 2015

  2. [2]

    Primal-dual strategy for constrained optimal control problems

    Ma ¨ ıtine Bergounioux, Kazufumi Ito, and Karl Kunisch. Primal-dual strategy for constrained optimal control problems. SIAM Journal on Control and Optimization , 37(4):1176–1194, 1999

  3. [3]

    Volume effects in the Keller–Segel model: energy estimates preventing blow-up

    Vincent Calvez and Jos´ e A Carrillo. Volume effects in the Keller–Segel model: energy estimates preventing blow-up. Journal de math´ ematiques pures et appliqu´ ees, 86(2):155–175, 2006

  4. [4]

    Cross diffusion and nonlinear diffusion preventing blow up in the Keller–Segel model

    Jos´ e Antonio Carrillo, Sabine Hittmeir, and Ansgar J¨ ungel. Cross diffusion and nonlinear diffusion preventing blow up in the Keller–Segel model. Mathematical Models and Methods in Applied Sciences , 22(12):1250041, 32 2012

  5. [5]

    A positivity preserving, energy stable finite dif- ference scheme for the Flory-Huggins-Cahn-Hilliard-Navier-Stokes system

    Wenbin Chen, Jianyu Jing, Cheng Wang, and Xiaoming Wang. A positivity preserving, energy stable finite dif- ference scheme for the Flory-Huggins-Cahn-Hilliard-Navier-Stokes system. Journal of Scientific Computing , 92(2):31, 2022

  6. [6]

    Positivity-preserving, energy stable numerical schemes for the Cahn-Hilliard equation with logarithmic potential

    Wenbin Chen, Cheng Wang, Xiaoming Wang, and Steven M Wise. Positivity-preserving, energy stable numerical schemes for the Cahn-Hilliard equation with logarithmic potential. Journal of Computational Physics: X , 3:100031, 2019

  7. [7]

    A new Lagrange multiplier approach for gradient flows

    Qing Cheng, Chun Liu, and Jie Shen. A new Lagrange multiplier approach for gradient flows. Computer Methods in Applied Mechanics and Engineering , 367:113070, 2020

  8. [8]

    Multiple scalar auxiliary variable (MSA V) approach and its application to the phase- field vesicle membrane model

    Qing Cheng and Jie Shen. Multiple scalar auxiliary variable (MSA V) approach and its application to the phase- field vesicle membrane model. SIAM Journal on Scientific Computing , 40(6):A3982–A4006, 2018

Show all 39 references
  1. [9]

    Global constraints preserving scalar auxiliary variable schemes for gradient flows

    Qing Cheng and Jie Shen. Global constraints preserving scalar auxiliary variable schemes for gradient flows. SIAM Journal on Scientific Computing , 42(4):A2489–A2513, 2020

  2. [10]

    A new Lagrange multiplier approach for constructing structure preserving schemes, I

    Qing Cheng and Jie Shen. A new Lagrange multiplier approach for constructing structure preserving schemes, I. Positivity preserving. Computer Methods in Applied Mechanics and Engineering , 391:114585, 2022

  3. [11]

    A new Lagrange multiplier approach for constructing structure preserving schemes, II

    Qing Cheng and Jie Shen. A new Lagrange multiplier approach for constructing structure preserving schemes, II. Bound preserving. SIAM Journal on Numerical Analysis , 60(3):970–998, 2022

  4. [12]

    High-order positivity-preserving hybrid finite-volume-finite-difference methods for chemotaxis systems

    Alina Chertock, Yekaterina Epshteyn, Hengrui Hu, and Alexander Kurganov. High-order positivity-preserving hybrid finite-volume-finite-difference methods for chemotaxis systems. Advances in Computational Mathe- matics, 44(1):327–350, 2018

  5. [13]

    A second-order positivity preserving central-upwind scheme for chemo- taxis and haptotaxis models

    Alina Chertock and Alexander Kurganov. A second-order positivity preserving central-upwind scheme for chemo- taxis and haptotaxis models. Numerische Mathematik , 111:169–205, 2008

  6. [14]

    Numerical solution of the Navier-Stokes equations

    Alexandre Joel Chorin. Numerical solution of the Navier-Stokes equations. Mathematics of Computation , 22(104):745–762, 1968

  7. [15]

    The Keller–Segel model with logistic sensitivity function and small diffusivity

    Yasmin Dolak and Christian Schmeiser. The Keller–Segel model with logistic sensitivity function and small diffusivity. SIAM Journal on Applied Mathematics , 66(1):286–308, 2005

  8. [16]

    Fully discrete analysis of a discontinuous finite element method for the Keller-Segel chemotaxis model

    Yekaterina Epshteyn and Ahmet Izmirlioglu. Fully discrete analysis of a discontinuous finite element method for the Keller-Segel chemotaxis model. Journal of Scientific Computing , 40(1):211–256, 2009

  9. [17]

    Finite-dimensional variational inequalities and complementarity prob- lems

    Francisco Facchinei and Jong-Shi Pang. Finite-dimensional variational inequalities and complementarity prob- lems. Springer Science & Business Media, 2007

  10. [18]

    A finite volume scheme for the Patlak–Keller–Segel chemotaxis model

    Francis Filbet. A finite volume scheme for the Patlak–Keller–Segel chemotaxis model. Numerische Mathematik , 104:457–488, 2006

  11. [19]

    An overview of projection methods for incompressible flows

    Jean-Luc Guermond, Peter Minev, and Jie Shen. An overview of projection methods for incompressible flows. Computer Methods in Applied Mechanics and Engineering , 195(44-47):6011–6045, 2006

  12. [20]

    Finite-dimensional variational inequality and nonlinear complementarity problems: a survey of theory, algorithms and applications

    Patrick T Harker and Jong-Shi Pang. Finite-dimensional variational inequality and nonlinear complementarity problems: a survey of theory, algorithms and applications. Mathematical programming, 48(1):161–220, 1990

  13. [21]

    Global existence for a parabolic chemotaxis model with prevention of over- crowding

    Thomas Hillen and Kevin Painter. Global existence for a parabolic chemotaxis model with prevention of over- crowding. Advances in Applied Mathematics , 26(4):280–301, 2001

  14. [22]

    From 1970 until present: the Keller-Segel model in chemotaxis and its consequences

    Dirk Horstmann. From 1970 until present: the Keller-Segel model in chemotaxis and its consequences. 2003

  15. [23]

    A linear second-order maximum bound principle-preserving BDF scheme for the Allen-Cahn equation with a general mobility

    Dianming Hou, Lili Ju, and Zhonghua Qiao. A linear second-order maximum bound principle-preserving BDF scheme for the Allen-Cahn equation with a general mobility. Mathematics of Computation , 92(344):2515– 2542, 2023

  16. [24]

    Bound/positivity preserving and energy stable scalar auxiliary variable schemes for dissipative systems: Applications to Keller–Segel and Poisson–Nernst–Planck equations

    Fukeng Huang and Jie Shen. Bound/positivity preserving and energy stable scalar auxiliary variable schemes for dissipative systems: Applications to Keller–Segel and Poisson–Nernst–Planck equations. SIAM Journal on Scientific Computing , 43(3):A1832–A1857, 2021

  17. [25]

    Lagrange multiplier approach to variational problems and applications

    Kazufumi Ito and Karl Kunisch. Lagrange multiplier approach to variational problems and applications . SIAM, 2008

  18. [26]

    Unconditionally maximum bound principle preserving linear schemes for the conservative Allen–Cahn equation with nonlocal constraint

    Jingwei Li, Lili Ju, Yongyong Cai, and Xinlong Feng. Unconditionally maximum bound principle preserving linear schemes for the conservative Allen–Cahn equation with nonlocal constraint. Journal of Scientific Computing , 87:1–32, 2021

  19. [27]

    Positivity-preserving and asymptotic preserving method for 2d Keller-Segal equations

    Jian-Guo Liu, Li Wang, and Zhennan Zhou. Positivity-preserving and asymptotic preserving method for 2d Keller-Segal equations. Mathematics of Computation , 87(311):1165–1189, 2018

  20. [28]

    On error estimates of projection methods for Navier–Stokes equations: first-order schemes

    Jie Shen. On error estimates of projection methods for Navier–Stokes equations: first-order schemes. SIAM Journal on Numerical Analysis , 29(1):57–77, 1992

  21. [29]

    On error estimates of some higher order projection and penalty-projection methods for Navier-Stokes equations

    Jie Shen. On error estimates of some higher order projection and penalty-projection methods for Navier-Stokes equations. Numerische Mathematik , 62(1):49–73, 1992

  22. [30]

    On pressure stabilization method and projection method for unsteady Navier-Stokes equations

    Jie Shen. On pressure stabilization method and projection method for unsteady Navier-Stokes equations. In Advances in Computer Methods for Partial Differential Equations . Citeseer, 1992

  23. [31]

    Spectral methods: algorithms, analysis and applications , volume 41

    Jie Shen, Tao Tang, and Li-Lian Wang. Spectral methods: algorithms, analysis and applications , volume 41. Springer Science & Business Media, 2011

  24. [32]

    Unconditionally bound preserving and energy dissipative schemes for a class of Keller–Segel equations

    Jie Shen and Jie Xu. Unconditionally bound preserving and energy dissipative schemes for a class of Keller–Segel equations. SIAM Journal on Numerical Analysis , 58(3):1674–1695, 2020

  25. [33]

    A new class of efficient and robust energy stable schemes for gradient flows

    Jie Shen, Jie Xu, and Jiang Yang. A new class of efficient and robust energy stable schemes for gradient flows. SIAM Review, 61(3):474–506, jan 2019. 33

  26. [34]

    Numerical approximations of Allen-Cahn and Cahn-Hilliard equations

    Jie Shen and Xiaofeng Yang. Numerical approximations of Allen-Cahn and Cahn-Hilliard equations. Discrete and Continuous Dynamical Systems , 28(4):1669–1691, 2010

  27. [35]

    Sur l’approximation de la solution des ´ equations de navier-stokes par la m´ ethode des pas frac- tionnaires (ii)

    Roger Temam. Sur l’approximation de la solution des ´ equations de navier-stokes par la m´ ethode des pas frac- tionnaires (ii). Archive for Rational Mechanics and Analysis , 33:377–385, 1969

  28. [36]

    Positivity preserving and mass conservative projection method for the Poisson– Nernst–Planck equation

    Fenghua Tong and Yongyong Cai. Positivity preserving and mass conservative projection method for the Poisson– Nernst–Planck equation. SIAM Journal on Numerical Analysis , 62(4):2004–2024, 2024

  29. [37]

    Stability and error estimates of local discontinuous Galerkin methods with implicit-explicit time-marching for advection-diffusion problems

    Haijin Wang, Chi-Wang Shu, and Qiang Zhang. Stability and error estimates of local discontinuous Galerkin methods with implicit-explicit time-marching for advection-diffusion problems. SIAM Journal on Numerical Analysis, 53(1):206–227, 2015

  30. [38]

    Fully decoupled and energy stable BDF schemes for a class of Keller-Segel equations

    Shufen Wang, Simin Zhou, Shuxun Shi, and Wenbin Chen. Fully decoupled and energy stable BDF schemes for a class of Keller-Segel equations. Journal of Computational Physics , 449:110799, 2022

  31. [39]

    Finite volume methods for a Keller–Segel system: discrete energy, error estimates and numerical blow-up analysis

    Guanyu Zhou and Norikazu Saito. Finite volume methods for a Keller–Segel system: discrete energy, error estimates and numerical blow-up analysis. Numerische Mathematik , 135(1):265–311, 2017. 34

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