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BEGIN:VEVENT
SUMMARY:Yaping Wu (Capital Normal University)
DTSTART;VALUE=DATE-TIME:20200803T130000Z
DTEND;VALUE=DATE-TIME:20200803T133000Z
DTSTAMP;VALUE=DATE-TIME:20200812T071831Z
UID:BIRS_20w5205/1
DESCRIPTION:Title: The spectral stability of bacteria pulse wave for a Kel
ler-Segel chemotactic model\nby Yaping Wu (Capital Normal University) as p
art of BIRS workshop: Interfacial Phenomena in Reaction-Diffusion Systems\
n\n\nAbstract\nIn this talk we shall talk about our recent work on the spe
ctral stability/instability of the whole family of explicit traveling wave
s $(B(x-ct)\,S(x-ct))$ in some weighted spaces\, by applying detailed sp
ectral analysis\, Evan's function method and numerical simulation. We shal
l also talk about our work on the local well-posedness of solution for the
original Keller-Segel model \\eqref{KS}.\n\nIt's a joint work with Yi Li\
, Yong Li and Hao Zhang.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Quentin Griette (University of Bordeaux)
DTSTART;VALUE=DATE-TIME:20200803T134000Z
DTEND;VALUE=DATE-TIME:20200803T141000Z
DTSTAMP;VALUE=DATE-TIME:20200812T071831Z
UID:BIRS_20w5205/2
DESCRIPTION:Title: Sharp discontinuous traveling waves in a hyperbolic Kel
ler–Segel equation\nby Quentin Griette (University of Bordeaux) as part
of BIRS workshop: Interfacial Phenomena in Reaction-Diffusion Systems\n\n\
nAbstract\nThis talk concerns a hyperbolic model of cell-cell repulsion wi
th a dynamics in the population of cells. More precisely\, we consider a p
opulation of cells producing a field (the “pressure”) which induces a
motion of the cells following the opposite of the gradient. The field indi
cates the local density of population and we assume that cells try to avoi
d crowded areas and prefer locally empty spaces which are far away from th
e carrying capacity. We analyze the well-posedness property of the associa
ted Cauchy problem on the real line. We start from bounded initial conditi
ons and we consider some invariant properties of the initial conditions su
ch as the continuity\, smoothness and monotony. We also describe in detail
the behavior of the level sets near the propagating boundary of the solut
ion and we find that an asymptotic jump is formed on the solution for a na
tural class of initial conditions. Finally\, we prove the existence of sha
rp traveling waves for this model\, which are particular solutions traveli
ng at a constant speed\, and argue that sharp traveling waves are necessar
ily discontinuous. This analysis is confirmed by numerical simulations of
the PDE problem. \n\nThis is a joint work with Xiaoming Fu and Pierre Maga
l.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Xing Liang (University of Science and Technology of China)
DTSTART;VALUE=DATE-TIME:20200803T142000Z
DTEND;VALUE=DATE-TIME:20200803T145000Z
DTSTAMP;VALUE=DATE-TIME:20200812T071831Z
UID:BIRS_20w5205/3
DESCRIPTION:Title: Spreading speeds of nonlocal diffusion KPP equations\nb
y Xing Liang (University of Science and Technology of China) as part of BI
RS workshop: Interfacial Phenomena in Reaction-Diffusion Systems\n\nAbstra
ct: TBA\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Thomas Giletti (University of Lorraine)
DTSTART;VALUE=DATE-TIME:20200804T130000Z
DTEND;VALUE=DATE-TIME:20200804T133000Z
DTSTAMP;VALUE=DATE-TIME:20200812T071831Z
UID:BIRS_20w5205/4
DESCRIPTION:Title: Propagating terraces in multidimensional and spatially
periodic domains\nby Thomas Giletti (University of Lorraine) as part of BI
RS workshop: Interfacial Phenomena in Reaction-Diffusion Systems\n\n\nAbst
ract\nThis talk will be devoted to the existence of pulsating travelling f
ront solutions for spatially periodic heterogeneous reaction-diffusion equ
ations in arbitrary dimension\, in the multistable case. In general\, the
notion of a single front is not sufficient to understand the dynamics of s
olutions\, and we instead observe the appearance of a so-called propagatin
g terrace. This roughly refers to a finite family of stacked fronts connec
ting intermediate stable steady states and whose speeds are ordered. Surpr
isingly\, for a given equation\, the shape of this terrace (i.e.\, the inv
olved intermediate steady states or even their number) may depend on the d
irection of the propagation. This in turn raises some difficulties in the
spreading shape of solutions of the evolution problem. The presented resul
ts come from a series of collaborations with W. Ding\, A. Ducrot\, H. Mata
no and L. Rossi.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nao Hamamuki (Hokkaido University)
DTSTART;VALUE=DATE-TIME:20200804T133000Z
DTEND;VALUE=DATE-TIME:20200804T140000Z
DTSTAMP;VALUE=DATE-TIME:20200812T071831Z
UID:BIRS_20w5205/5
DESCRIPTION:Title: Asymptotic behavior of solutions to level-set mean curv
ature flow equations with discontinuous source terms\nby Nao Hamamuki (Hok
kaido University) as part of BIRS workshop: Interfacial Phenomena in React
ion-Diffusion Systems\n\n\nAbstract\nMotivated by the two-dimensional nucl
eation of crystal growth\,\nwe consider the initial-value problem of the l
evel-set mean curvature flow equation with discontinuous source terms.\n\n
We discuss uniqueness and existence of viscosity solutions and study the a
symptotic shape of solutions. Applying the game-theoretic interpretation f
or this problem\, we also study the asymptotic speed of solutions.\n\nThis
talk is based on a joint work with K. Misu (Hokkaido University).\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Samuel Nordmann (University of Tel-Aviv)
DTSTART;VALUE=DATE-TIME:20200804T140000Z
DTEND;VALUE=DATE-TIME:20200804T143000Z
DTSTAMP;VALUE=DATE-TIME:20200812T071831Z
UID:BIRS_20w5205/6
DESCRIPTION:Title: The symmetry of stable solutions of semilinear elliptic
equations\nby Samuel Nordmann (University of Tel-Aviv) as part of BIRS wo
rkshop: Interfacial Phenomena in Reaction-Diffusion Systems\n\n\nAbstract\
nConsider a general semilinear elliptic equation with Neumann boundary con
ditions. A seminal result of Casten\, Holland (1978) and Matano (1979) sta
tes that\, if the domain is convex and bounded\, any stable solution is co
nstant. In this talk\, we will investigate whether this classification res
ult extends to convex unbounded domains\, or to some non-convex domains. T
hese questions involve the geometry of the domain in a rather intricate wa
y. In particular\, our results recover and extend some classical results o
n De Giorgi's conjecture about the classification of stable solutions of t
he Allen-Cahn equation in $R^n$.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Cole Graham (Stanford University)
DTSTART;VALUE=DATE-TIME:20200804T143000Z
DTEND;VALUE=DATE-TIME:20200804T150000Z
DTSTAMP;VALUE=DATE-TIME:20200812T071831Z
UID:BIRS_20w5205/7
DESCRIPTION:Title: Reaction-diffusion equations in the half-space\nby Cole
Graham (Stanford University) as part of BIRS workshop: Interfacial Phenom
ena in Reaction-Diffusion Systems\n\n\nAbstract\nThe interplay between rea
ction-diffusion evolution and spatial boundary has received a great deal o
f recent attention. In this talk\, we consider an essential example: react
ion-diffusion equations in the half-space. Using the maximum principle and
the sliding method\, we handle a host of reactions (monostable\, ignition
\, and bistable) under a wide class of boundary conditions (Dirichlet and
Robin). We consider the existence and uniqueness of steady states\, the as
ymptotic speed of propagation\, and the existence of traveling waves. This
is joint work with Henri Berestycki.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ryunosuke Mori (Meiji University)
DTSTART;VALUE=DATE-TIME:20200805T130000Z
DTEND;VALUE=DATE-TIME:20200805T133000Z
DTSTAMP;VALUE=DATE-TIME:20200812T071831Z
UID:BIRS_20w5205/8
DESCRIPTION:Title: Mathematical Analysis of a Reaction-Diffusion Model for
Neolithic Transition in Europe\nby Ryunosuke Mori (Meiji University) as p
art of BIRS workshop: Interfacial Phenomena in Reaction-Diffusion Systems\
n\n\nAbstract\nIn 1996\, Aoki\, Shida and Shigesada proposed a three-compo
nent reaction-diffusion model describing the spread of the early farming d
uring the New Stone Age. By numerical simulations and some formal lineariz
ation arguments\, they concluded that there are four different types of sp
reading behaviors depending on the parameter values.\n\nIn this talk\, we
give theoretical justification to all of the four types of spreading behav
iors observed by Aoki et al. We also investigate the case where the motili
ty of the hunter-gatherers is not equal to that of the farmers\, which is
not discussed in the paper of Aoki et al.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Chang-Hong Wu (National Chiao Tung University)
DTSTART;VALUE=DATE-TIME:20200805T134000Z
DTEND;VALUE=DATE-TIME:20200805T141000Z
DTSTAMP;VALUE=DATE-TIME:20200812T071831Z
UID:BIRS_20w5205/9
DESCRIPTION:Title: Wave Propagation in Two-Species Strong Competition Mode
ls\nby Chang-Hong Wu (National Chiao Tung University) as part of BIRS work
shop: Interfacial Phenomena in Reaction-Diffusion Systems\n\n\nAbstract\nW
ave propagation for the two-species Lotka-Volterra competition models has
been studied widely. In this talk\, we shall focus on the bistable waves a
nd discuss some recent progress.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Wenxian Shen (Auburn University)
DTSTART;VALUE=DATE-TIME:20200805T143000Z
DTEND;VALUE=DATE-TIME:20200805T150000Z
DTSTAMP;VALUE=DATE-TIME:20200812T071831Z
UID:BIRS_20w5205/10
DESCRIPTION:Title: Can chemotaxis speed up or slow down the spatial spread
ing in parabolic-elliptic Keller-Segel systems with logistic source?\nby W
enxian Shen (Auburn University) as part of BIRS workshop: Interfacial Phen
omena in Reaction-Diffusion Systems\n\nAbstract: TBA\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Masahiko Shimojo (Okayama University of Sciences)
DTSTART;VALUE=DATE-TIME:20200806T130000Z
DTEND;VALUE=DATE-TIME:20200806T133000Z
DTSTAMP;VALUE=DATE-TIME:20200812T071831Z
UID:BIRS_20w5205/11
DESCRIPTION:Title: Convergence to traveling wave for the logarithmic diffu
sion equation with reaction term\nby Masahiko Shimojo (Okayama University
of Sciences) as part of BIRS workshop: Interfacial Phenomena in Reaction-D
iffusion Systems\n\nAbstract: TBA\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Maolin Zhou (Nankai University)
DTSTART;VALUE=DATE-TIME:20200806T133000Z
DTEND;VALUE=DATE-TIME:20200806T140000Z
DTSTAMP;VALUE=DATE-TIME:20200812T071831Z
UID:BIRS_20w5205/12
DESCRIPTION:Title: The principal eigenvalue problem for some second order
elliptic and parabolic operators with large advection\nby Maolin Zhou (Nan
kai University) as part of BIRS workshop: Interfacial Phenomena in Reactio
n-Diffusion Systems\n\n\nAbstract\nIn this talk\, we will show some recent
results about the limit problem of the principal eigenvalue for some seco
nd elliptic and parabolic operators in one dimensional space when the adve
ction coefficient converges to infinity. It has some applications to the e
xistence and stability of solutions of single equations and systems. This
is a joint work with Shuang Liu\, Yuan Lou and Rui Peng.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Harunori Monobe (Okayama University)
DTSTART;VALUE=DATE-TIME:20200806T140000Z
DTEND;VALUE=DATE-TIME:20200806T143000Z
DTSTAMP;VALUE=DATE-TIME:20200812T071831Z
UID:BIRS_20w5205/13
DESCRIPTION:Title: Fast reaction limit of three-components reaction-diffus
ion systems and free boundary problems describing population dynamics\nby
Harunori Monobe (Okayama University) as part of BIRS workshop: Interfacial
Phenomena in Reaction-Diffusion Systems\n\nAbstract: TBA\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Léo Girardin (University of Paris-Sud)
DTSTART;VALUE=DATE-TIME:20200806T143000Z
DTEND;VALUE=DATE-TIME:20200806T150000Z
DTSTAMP;VALUE=DATE-TIME:20200812T071831Z
UID:BIRS_20w5205/14
DESCRIPTION:Title: Strong competition limit\, traveling waves and best dis
persal strategy for Lotka-Volterra competitive systems\nby Léo Girardin (
University of Paris-Sud) as part of BIRS workshop: Interfacial Phenomena i
n Reaction-Diffusion Systems\n\n\nAbstract\nIn this talk\, I will present
an ongoing work in collaboration with\nDanielle Hilhorst about the singula
r limit of a large class of\nstrongly coupled\, strongly competitive two-s
pecies reaction--diffusion \nsystems. Particular cases are the standard Lo
tka--Volterra system\, the\nPotts--Petrovskii cross-taxis system and the S
KT cross-diffusion system. \nWe focus on the singular limit of traveling w
aves and use the sign of\nthe wave speed as a criterion to compare dispers
al--growth strategies.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jean-Michel Roquejoffre (Universite Paul Sabatier)
DTSTART;VALUE=DATE-TIME:20200807T130000Z
DTEND;VALUE=DATE-TIME:20200807T133000Z
DTSTAMP;VALUE=DATE-TIME:20200812T071831Z
UID:BIRS_20w5205/15
DESCRIPTION:Title: Properties of a free boundary driven by a line of fast
diffusion\nby Jean-Michel Roquejoffre (Universite Paul Sabatier) as part o
f BIRS workshop: Interfacial Phenomena in Reaction-Diffusion Systems\n\n\n
Abstract\nThe situation is the following: a line\, having a strong diffusi
on on its own\,\nexchanges mass with the half plane below\, supposed to be
a reactive medium. A front propagates\nboth on the line and below\, and o
ne wishes to describe its shape. This setting was proposed\n(collaboration
with H. Berestycki and L. Rossi) as a model of how biological invasions c
an be\nenhanced by transportation networks.\n\nNumerical simulations\, due
to A.-C. Coulon\, reveal an a priori surprising phenomenon:\nthe solution
is not monotone in the direction orthogonal to the line. We will try to\n
understand this feature in the particular case of a free boundary problem
that can be\nobtained as a limiting case of the original reaction-diffusio
n system\, amd discuss\nfurther features of the free boundary\, such as it
s shape at infinity\, or what happens when the\ndiffusion on the line beco
mes infinite.\n\nJoint work with L. Caffarelli.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Changfeng Gui (University of Texas at San Antonio)
DTSTART;VALUE=DATE-TIME:20200807T134000Z
DTEND;VALUE=DATE-TIME:20200807T141000Z
DTSTAMP;VALUE=DATE-TIME:20200812T071831Z
UID:BIRS_20w5205/16
DESCRIPTION:Title: Propagation acceleration in reaction diffusion equation
s with a fractional Laplacian\nby Changfeng Gui (University of Texas at Sa
n Antonio) as part of BIRS workshop: Interfacial Phenomena in Reaction-Dif
fusion Systems\n\n\nAbstract\nIn this talk\, I will present recent result
s on the propagation speed in a reaction diffusion system with an anomal
ous Levy process diffusion\, modeled by a nonlocal equation with a frac
tional Laplacian and a generalized KPP type monostable nonlinearity. Giv
en a typical Heavy side initial datum\, we show that the speed of interf
ace propagation displays an algebraic rate behavior in time\, in contra
st to the known linear rate in the classical model of Brownian motion and
the exponential rate in the KPP model with the anomalous diffusion\, an
d depends on the sensitive balance between the anomaly of the diffusion pr
ocess and the strength of monostable reaction. In particular\, for th
e combustion model with\na fractional Laplacian $(-\\Delta)^{s}$\, we sho
w that the speed of propagation transits continuously from being linear
in time\, when a traveling wave solution exists for $s \\in (1/2\, 1)$\,
to being algebraic in time with a power reciprocal to $2s$\, when no t
raveling wave solution exists for $s \\in (0\, 1/2)$.\n\n The talk is b
ased on a joint work with Jerome Coville and Mingfeng Zhao.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sigurd Angenent (University of Wisconsin)
DTSTART;VALUE=DATE-TIME:20200807T142000Z
DTEND;VALUE=DATE-TIME:20200807T145000Z
DTSTAMP;VALUE=DATE-TIME:20200812T071831Z
UID:BIRS_20w5205/17
DESCRIPTION:Title: Dynamics of convex mean curvature flow\nby Sigurd Angen
ent (University of Wisconsin) as part of BIRS workshop: Interfacial Phenom
ena in Reaction-Diffusion Systems\n\n\nAbstract\nMean Curvature Flow defin
es a gradient-like dynamical system on the space of convex hypersurfaces.
I will discuss what is known about the fixed points and connecting orbits
of this flow.\n
END:VEVENT
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