❯♥✐✈❡rs✐❞❛❞❡ ❞❡ ❇r❛sí❧✐❛
■♥st✐t✉t♦ ❞❡ ❈✐ê♥❝✐❛s ❊①❛t❛s
❉❡♣❛rt❛♠❡♥t♦ ❞❡ ▼❛t❡♠át✐❝❛
Pr♦❜❧❡♠❛s ❊❧í♣t✐❝♦s ❙❡♠✐❧✐♥❡❛r❡s ❝♦♠
❉❡♣❡♥❞ê♥❝✐❛ ❞♦ ●r❛❞✐❡♥t❡
♣♦r
P❡❞r♦ ▼❛♥✉❡❧ ❙á♥❝❤❡③ ❆❣✉✐❧❛r
❇r❛sí❧✐❛
❯♥✐✈❡rs✐❞❛❞❡ ❞❡ ❇r❛sí❧✐❛ ■♥st✐t✉t♦ ❞❡ ❈✐ê♥❝✐❛s ❊①❛t❛s ❉❡♣❛rt❛♠❡♥t♦ ❞❡ ▼❛t❡♠át✐❝❛
Pr♦❜❧❡♠❛s ❊❧í♣t✐❝♦s ❙❡♠✐❧✐♥❡❛r❡s ❝♦♠
❉❡♣❡♥❞ê♥❝✐❛ ❞♦ ●r❛❞✐❡♥t❡
♣♦r
P❡❞r♦ ▼❛♥✉❡❧ ❙á♥❝❤❡③ ❆❣✉✐❧❛r
∗❉✐ss❡rt❛çã♦ ❛♣r❡s❡♥t❛❞❛ ❛♦ ❉❡♣❛rt❛♠❡♥t♦ ❞❡ ▼❛t❡♠át✐❝❛ ❞❛ ❯♥✐✈❡rs✐❞❛❞❡ ❞❡ ❇r❛sí❧✐❛ ❝♦♠♦ ♣❛rt❡ ❞♦s r❡q✉✐s✐t♦s ♥❡❝❡ssár✐♦s ♣❛r❛ ♦❜t❡♥çã♦ ❞♦ ❣r❛✉ ❞❡
▼❊❙❚❘❊ ❊▼ ▼❆❚❊▼➪❚■❈❆
❇r❛sí❧✐❛✱ ✷✸ ❞❡ ❛❣♦st♦ ❞❡ ✷✵✶✸
❈♦♠✐ssã♦ ❊①❛♠✐♥❛❞♦r❛✿
Pr♦❢a✳ ❉r❛✳ ▼❛♥✉❡❧❛ ❈❛❡t❛♥♦ ▼❛rt✐♥s ❞❡ ❘❡③❡♥❞❡ ✭❯♥❇✮✕❖r✐❡♥t❛❞♦r❛
Pr♦❢✳ ❉r✳ ❯❜❡r❧â♥❞✐♦ ❇❛t✐st❛ ❙❡✈❡r♦ ✭❯❋P❇✮
Pr♦❢✳ ❉r✳ ❘✐❝❛r❞♦ ❘✉✈✐❛r♦ ✭❯♥❇✮
❆❣r❛❞❡❝✐♠❡♥t♦s
❖❜r✐❣❛❞♦✱ ♠❡✉ ❉❡✉s✱ ♣♦r ❞❛r✲♠❡ ❢♦rç❛s ♣❛r❛ ❧✐❞❛r ❝♦♠ ❛s ❛❞✈❡rs✐❞❛❞❡s ❡ ❛ss✐♠ ❝✉♠♣r✐r ❝♦♠ ♠❛✐s ✉♠ ♦❜❥❡t✐✈♦ ❡♠ ♠✐♥❤❛ ✈✐❞❛✳
➚ ♣r♦❢❡ss♦r❛ ▼❛♥✉❡❧❛ ❈❛❡t❛♥♦ ▼❛rt✐♥s ❞❡ ❘❡③❡♥❞❡✱ ♣❡❧❛ ♣❛❝✐ê♥❝✐❛ ❡ ❛♣♦✐♦ ♥❡st❡ tr❛❜❛❧❤♦✱ ♣❡❧♦s ❝♦♥s❡❧❤♦s ❡✱ s♦❜r❡t✉❞♦✱ ♣♦r s✉❛ ❛♠✐③❛❞❡✳
❆♦s ♠❡♠❜r♦s ❞❛ ❜❛♥❝❛ ❡①❛♠✐♥❛❞♦r❛✱ ♣r♦❢❡ss♦r❡s ❯❜❡r❧â♥❞✐♦ ❇❛t✐st❛ ❙❡✈❡r♦✱ ❘✐❝❛r❞♦ ❘✉✈✐❛r♦✱ ❈❛r❧♦s ❆❧❜❡rt♦ P❡r❡✐r❛ ❞♦s ❙❛♥t♦s✱ ♣❡❧❛s ♦♣♦rt✉♥❛s ❝♦rr❡çõ❡s ❡ s✉❣❡st♦✄❡s✳
❆♦s ♠❡✉s ♣❛✐s✱ ●❧❛❞②s ❚❡♦❞♦♥✐❧❛ ❆❣✉✐❧❛r ❱✐t❡r✐ ❡ ❍❡r♠❡♥❡❣✐❧❞♦ ❙á♥❝❤❡③ ❱❡❣❛✱ ♣❡❧❛s ♣❛❧❛✈r❛s ❞❡ ❛❧❡♥t♦ ❡ ♣♦r t❡r❡♠ ❢♦♠❡♥t❛❞♦ ❡♠ ♠✐♠ ♦ ❞❡s❡❥♦ ❞❡ s✉♣❡r❛çã♦ ♥❛ ✈✐❞❛✳
❆♦ ❈◆Pq✱ ♣❡❧♦ ❛♣♦✐♦ ✜♥❛♥❝❡✐r♦ ❞✉r❛♥t❡ t♦❞♦ ♦ ♣❡rí♦❞♦✳
❘❡s✉♠♦
◆❡st❡ tr❛❜❛❧❤♦✱ ✐❧✉str❛♠♦s ❛ ✉t✐❧✐③❛çã♦ ❞❡ ❞♦✐s ♠ét♦❞♦s ❞✐❢❡r❡♥t❡s ✕ s✉❜ ❡ s✉♣❡rs♦❧✉çã♦ ❡ ✈❛r✐❛❝✐♦♥❛❧ ✕ ♥❛ ♦❜t❡♥çã♦ ❞❡ ❡①✐stê♥❝✐❛ ❞❡ s♦❧✉çã♦ ♣❛r❛ ✉♠❛ ❝❧❛ss❡ ❞❡ ♣r♦❜❧❡♠❛s ❡❧í♣t✐❝♦s s❡♠✐❧✐♥❡❛r❡s ❝✉❥❛ ♥ã♦✲❧✐♥❡❛r✐❞❛❞❡ ❛♣r❡s❡♥t❛ ❞❡♣❡♥❞ê♥❝✐❛ ❞♦ t❡r♠♦ ❣r❛❞✐❡♥t❡✳
P❛❧❛✈r❛s✲❝❤❛✈❡✿ s✉❜ ❡ s✉♣❡rs♦❧✉çã♦✱ P❛ss♦ ❞❛ ▼♦♥t❛♥❤❛✱ t❡r♠♦ ❣r❛❞✐❡♥t❡✱ ♣r♦❜❧❡♠❛s s✐♥❣✉❧❛r❡s✱ s♦❧✉çã♦ ❣r♦✉♥❞ st❛t❡✳
❆❜str❛❝t
■♥ t❤✐s ✇♦r❦ ✇❡ ✐❧❧✉str❛t❡ t❤❡ ❛♣♣❧✐❝❛t✐♦♥ ♦❢ t✇♦ ❞✐✛❡r❡♥t ♠❡t❤♦❞s ✕ ❧♦✇❡r ❛♥❞ ✉♣♣❡r s♦❧✉t✐♦♥ ❛♥❞ ✈❛r✐❛t✐♦♥❛❧ ✕ t♦ ♦❜t❛✐♥ t❤❡ ❡①✐st❡♥❝❡ ♦❢ ❛ s♦❧✉t✐♦♥ ❢♦r ❛ ❝❧❛ss ♦❢ s❡♠✐❧✐♥❡❛r ❡❧❧✐♣t✐❝ ♣r♦❜❧❡♠s ✇❤♦s❡ ♥♦♥❧✐♥❡❛r✐t② ♣r❡s❡♥ts ❞❡♣❡♥❞❡♥❝❡ ♦♥ t❤❡ ❣r❛❞✐❡♥t t❡r♠✳
❑❡② ✇♦r❞s✿ ❧♦✇❡r ❛♥❞ ✉♣♣❡r s♦❧✉t✐♦♥✱ ▼♦✉♥t❛✐♥ P❛ss✱ ❣r❛❞✐❡♥t t❡r♠✱ s✐♥❣✉❧❛r ♣r♦❜❧❡♠s✱ ❣r♦✉♥❞ st❛t❡ s♦❧✉t✐♦♥✳
❙✉♠ár✐♦
◆♦t❛çõ❡s ✶
■♥tr♦❞✉çã♦ ✹
✶ ◆♦çõ❡s ♣r❡❧✐♠✐♥❛r❡s ❡ r❡s✉❧t❛❞♦s ❛✉①✐❧✐❛r❡s ✶✸
✷ ❙♦❧✉çõ❡s ❣r♦✉♥❞ st❛t❡ ♣❛r❛ ❛ ❡q✉❛çã♦ ❞❡ ▲❛♥❡✲❊♠❞❡♥✲❋♦✇❧❡r s✐♥❣✉❧❛r
❝♦♠ t❡r♠♦ ❞❡ ❝♦♥✈❡❝çã♦ s✉❜❧✐♥❡❛r ✷✹
✷✳✶ ❊①✐stê♥❝✐❛ ❞❡ ✉♠❛ s♦❧✉çã♦ ♣♦s✐t✐✈❛ ❡♠ ❞♦♠í♥✐♦s ❧✐♠✐t❛❞♦s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✺ ✷✳✷ ❊①✐stê♥❝✐❛ ❞❡ ✉♠❛ s♦❧✉çã♦ ❣r♦✉♥❞ st❛t❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✵
✸ ❊q✉❛çõ❡s ❡❧í♣t✐❝❛s s❡♠✐❧✐♥❡❛r❡s ❝♦♠ ❞❡♣❡♥❞ê♥❝✐❛ ❞♦ ❣r❛❞✐❡♥t❡ ✈✐❛
té❝♥✐❝❛ ❞♦ P❛ss♦ ❞❛ ▼♦♥t❛♥❤❛ ✹✷
✸✳✶ ❙♦❧✉çã♦ ♣❛r❛ ♦ ♣r♦❜❧❡♠❛ ✈❛r✐❛❝✐♦♥❛❧ ✈✐❛ té❝♥✐❝❛ ❞♦ P❛ss♦ ❞❛ ▼♦♥t❛♥❤❛ ✳ ✳ ✹✺ ✸✳✷ ❙♦❧✉çã♦ ♣❛r❛ ♦ ♣r♦❜❧❡♠❛ ♥ã♦ ✈❛r✐❛❝✐♦♥❛❧ ❛tr❛✈és ❞❡ ✉♠ ♠ét♦❞♦ ✐t❡r❛t✐✈♦ ✳ ✺✻
✹ ❆♣ê♥❞✐❝❡ ✺✾
◆♦t❛çõ❡s
◆❡st❡ tr❛❜❛❧❤♦✱ ❢❛③❡♠♦s ✉s♦ ❞❛s s❡❣✉✐♥t❡s ♥♦t❛çõ❡s✿
• Ω⊂RN é ✉♠ ❞♦♠í♥✐♦ ❧✐♠✐t❛❞♦ ❝♦♠ ❢r♦♥t❡✐r❛ s✉❛✈❡❀
• | · | r❡♣r❡s❡♥t❛ ❛ ♥♦r♠❛ ❡✉❝❧✐❞✐❛♥❛ ❡♠ RN, N ≥1❀
• Br ={x∈RN :|x|< r}, r >0❀
• ❉❛❞♦s ❛❜❡rt♦s Ω0, Ω ⊂RN✱ ❡s❝r❡✈❡♠♦s Ω0 ⊂⊂Ω q✉❛♥❞♦ Ω0 ❡stá ❝♦♠♣❛❝t❛♠❡♥t❡
❝♦♥t✐❞♦ ❡♠ Ω✱ ✐st♦ é✱ Ω0 é ✉♠ ❝♦♠♣❛❝t♦ ❝♦♥t✐❞♦ Ω❀
• λ1 é ♦ ♣r✐♠❡✐r♦ ❛✉t♦✈❛❧♦r ❞♦ ♣r♦❜❧❡♠❛
(
−∆ϕ =λϕ ❡♠ Ω,
ϕ = 0 s♦❜r❡ ∂Ω, (AV)
❡ ϕ1 é ✉♠❛ λ1✲❛✉t♦❢✉♥çã♦ ♣♦s✐t✐✈❛ ❞❡ (AV)❀
• ❯♠ ✈❡t♦r ❞❛ ❢♦r♠❛ α = (α1, . . . , αN)✱ ♦♥❞❡ ❝❛❞❛ ❝♦♠♣♦♥❡♥t❡ αi ∈ N∪ {0}✱ é ❝❤❛♠❛❞♦ ✉♠ ♠✉❧t✐✲í♥❞✐❝❡ ❞❡ ♦r❞❡♠
|α|=α1+· · ·+αN;
• ❉❛❞♦ ✉♠ ♠✉❧t✐✲í♥❞✐❝❡ α✱ ❞❡✜♥✐♠♦s
Dαu:= ∂
|α|u
∂α1x
1. . . ∂αNxN
,
q✉❛♥❞♦ ❛ ❞❡r✐✈❛❞❛ ♠✐st❛ ❞♦ ❧❛❞♦ ❞✐r❡✐t♦ ❡①✐st❡❀
◆♦t❛çõ❡s ✷
• C(Ω) =
(
u∈C(Ω) :u é ✉♥✐❢♦r♠❡♠❡♥t❡ ❝♦♥tí♥✉❛ ❡♠ s✉❜❝♦♥❥✉♥t♦s
❧✐♠✐t❛❞♦s ❞❡Ω
)
,
❝✉❥❛ ♥♦r♠❛ é kukC(Ω) = sup
x∈Ω
|u(x)|;
• C0(Ω) sã♦ ❛s ❢✉♥çõ❡s ❝♦♥tí♥✉❛s ❞❡ s✉♣♦rt❡ ❝♦♠♣❛❝t♦ ❡♠ Ω❀
• Ck(Ω) ={u: Ω−→R:u é k ✈❡③❡s ❝♦♥t✐♥✉❛♠❡♥t❡ ❞✐❢❡r❡♥❝✐á✈❡❧ }✱k ∈N∪ {0}❀
• Ck(Ω) =
(
u∈Ck(Ω) :Dαu ✉♥✐❢♦r♠❡♠❡♥t❡ ❝♦♥tí♥✉❛ s♦❜r❡ s✉❜❝♦♥❥✉♥t♦s ❧✐♠✐t❛❞♦s ❞❡ Ω, ♣❛r❛ t♦❞♦ |α| ≤k
)
.
❆ss✐♠ s❡ u ∈ Ck(Ω)✱ ❡♥tã♦ Dαu ❡st❡♥❞❡✲s❡ ❝♦♥t✐♥✉❛♠❡♥t❡ ❛té Ω ♣❛r❛ ❝❛❞❛ ♠✉❧t✐✲ í♥❞✐❝❡ α✱ |α| ≤k✳
kukCk(Ω) =
X
|α|≤k
kDαuk C(Ω);
• C∞(Ω) = ∞
\
k=0
Ck(Ω) ❡ C∞(Ω) =
∞
\
k=0
Ck(Ω)❀
• Ck
0(Ω) =Ck(Ω)∩C0(Ω) ❡ C0∞(Ω) =C∞(Ω)∩C0(Ω)❀
• ❙❡❥❛ k∈N∪ {0} ❡0< γ ≤1✳ Ck,γ(Ω) ❞❡♥♦t❛ ♦ ❡s♣❛ç♦ ❞❡ ❍ö❧❞❡r ❞❛❞♦ ♣♦r
Ck,γ(Ω) ={u∈Ck(Ω) : [Dαu]
C0,γ(Ω) <∞, ♣❛r❛ t♦❞♦ ♠✉❧t✐✲í♥❞✐❝❡|α| ≤k},
♦♥❞❡ [Dαu]
C0,γ(Ω)= sup
x,y∈Ω
x6=y
|Dαu(x)−Dαu(y)|
|x−y|γ ✱ ❝✉❥❛ ♥♦r♠❛ é
kukCk,γ(Ω) =kukCk(Ω)+
X
|α|=k
[Dαu]
C0,γ(Ω), ♣❛r❛ t♦❞♦u∈Ck,γ(Ω);
• ❯♠❛ ❢✉♥çã♦ u : Ω−→R é ❝❤❛♠❛❞❛ ▲✐♣s❝❤✐t③ s❡ s❛t✐s❢❛③ |u(x)−u(y)| ≤C|x−y|✱
♣❛r❛ ❛❧❣✉♠❛ ❝♦♥st❛♥t❡C ❡ ♣❛r❛ t♦❞♦sx, y ∈Ω✳ ◆❡st❡ ❝❛s♦✱ ❡s❝r❡✈❡♠♦su∈Lip(Ω)❀
• u+(x) = max{u(x),0}✱ u−(x) = max{−u(x),0}❀
• ❖ ❡s♣❛ç♦ Lp(Ω) é ❞❡♥♦t❛❞♦ ♣♦r
Lp(Ω) ={f : Ω−→R:f é ♠❡♥s✉rá✈❡❧ ❡
Z
Ω
◆♦t❛çõ❡s ✸
❡♠ q✉❡ 1≤p <∞ ❡ Ω⊂RN é ✉♠ ❛❜❡rt♦ ❝♦♥❡①♦✱ ♠✉♥✐❞♦ ❝♦♠ ❛ ♥♦r♠❛ ❞❛❞❛ ♣♦r
kfkp =
Z
Ω
|f|p dx
1
p
;
• L∞(Ω)❞❡♥♦t❛ ♦ ❡s♣❛ç♦ ❞❛s ❢✉♥çõ❡s ♠❡♥s✉rá✈❡✐s q✉❡ sã♦ ❧✐♠✐t❛❞❛s q✉❛s❡ s❡♠♣r❡ ❡♠
Ω✱ ❝♦♠ ♥♦r♠❛ ❞❛❞❛ ♣♦r
kuk∞:= inf{C >0 :|u(x)| ≤C q✉❛s❡ s❡♠♣r❡ ❡♠ Ω};
• P❛r❛1≤p≤ ∞❡k∈N∪ {0}✱ ❞❡♥♦t❛♠♦s ♦ ❡s♣❛ç♦ ❞❡ ❙♦❜♦❧❡✈Wk,p(Ω)❝♦♠♦ s❡♥❞♦
Wk,p(Ω) :={u∈Lp(Ω) :Dαu∈Lp(Ω) ♣❛r❛ t♦❞♦ ♠✉❧t✐✲í♥❞✐❝❡ α t❛❧ q✉❡ |α| ≤k}, ❝♦♠ ♥♦r♠❛ ❞❛❞❛ ♣♦r
kukWk,p =
X
|α|≤k
Z
Ω
|Dαu|p
1
p
, s❡ 1≤p <∞,
X
|α|≤k
kDαuk∞, s❡p=∞;
• ❉❡♥♦t❛♠♦s ♣♦r X∗ ♦ ❡s♣❛ç♦ ❞✉❛❧ ❞❡ X✱ ❝♦♠ ♥♦r♠❛ ❞❛❞❛ ♣♦r
kIkX∗ = sup x∈X
kxkX=1
■♥tr♦❞✉çã♦
◆❛s ú❧t✐♠❛s ❞é❝❛❞❛s✱ ♦s ♣r♦❜❧❡♠❛s ❡❧í♣t✐❝♦s tê♠ ❝❤❛♠❛❞♦ ❛t❡♥çã♦ ❞♦s ♣❡sq✉✐s❛❞♦r❡s ❡♠ ❊q✉❛çõ❡s ❉✐❢❡r❡♥❝✐❛✐s P❛r❝✐❛✐s ♣❡❧❛s ❛♣❧✐❝❛çõ❡s ❡♠ ❞✐✈❡rs❛s ár❡❛s ❞♦ ❝♦♥❤❡❝✐♠❡♥t♦✳ ❊♠ ✈ár✐❛s ❞❡st❛s ❛♣❧✐❝❛çõ❡s✱ é ❞❡ ❢✉♥❞❛♠❡♥t❛❧ ✐♠♣♦rtâ♥❝✐❛ s❛❜❡r s❡ ❛ ❡q✉❛çã♦ q✉❡ ♠♦❞❡❧❛ ❝❡rt♦ ❢❡♥ô♠❡♥♦ ♣♦ss✉✐ s♦❧✉çã♦✳ ❈♦♠ ❡st❛ ✜♥❛❧✐❞❛❞❡✱ ❢♦r❛♠ ❞❡s❡♥✈♦❧✈✐❞❛s té❝♥✐❝❛s q✉❡ ❞❡t❡r♠✐♥❛♠ ❛ ❡①✐stê♥❝✐❛ ❞❡ s♦❧✉çõ❡s ❞❡ ♣r♦❜❧❡♠❛s ❡❧í♣t✐❝♦s✳ ◆❡st❡ tr❛❜❛❧❤♦✱ ♣♦r ❡①❡♠♣❧♦✱ ♥♦s ❝♦♥❝❡♥tr❛♠♦s ❡♠ ❞✉❛s té❝♥✐❝❛s q✉❡ ♠♦str❛♠ ❛ ❡①✐stê♥❝✐❛ ❞❡ s♦❧✉çã♦ ❞❡ ✉♠ t✐♣♦ ❡s♣❡❝í✜❝♦ ❞❡ ♣r♦❜❧❡♠❛s✳
❖ ▼ét♦❞♦ ❞❡ ❙✉❜ ❡ ❙✉♣❡rs♦❧✉çã♦ é ✉♠ ❞♦s ♠ét♦❞♦s ♠❛✐s ✉s❛❞♦s ♣❛r❛ ❡st✉❞❛r ♣r♦❜❧❡♠❛s ❡❧í♣t✐❝♦s ❡ r❡q✉❡r ❝❡rt❛ ❤❛❜✐❧✐❞❛❞❡ ❡♠ ❝❛❞❛ ❝❛s♦✳ ❙❛❜❡♠♦s q✉❡ s❡ ✉♠❛ ❢✉♥çã♦ ❝♦♥tí♥✉❛ ♠✉❞❛ ❞❡ s✐♥❛❧ ❡♠ ✉♠ ✐♥t❡r✈❛❧♦ ❢❡❝❤❛❞♦✱ ❡♥tã♦ ❡❧❛ ❤á ❞❡ t❡r ✉♠ ③❡r♦✳ ❆té ❝❡rt♦ ♣♦♥t♦✱ ♦ ♠ét♦❞♦ ❞❡ s✉❜ ❡ s✉♣❡rs♦❧✉çã♦ ♣♦❞❡ s❡r ✈✐st♦ ❝♦♠♦ ✉♠❛ ❡①t❡♥sã♦ ❞❡st❡ ❢❛t♦✳ ❆ ✐❞❡✐❛ ❞❡st❡ ♠ét♦❞♦ ❝♦♥s✐st❡ ❡♠ ❞❡t❡r♠✐♥❛r ✉♠❛ s✉❜s♦❧✉çã♦ u ❡ ✉♠❛ s✉♣❡rs♦❧✉çã♦ u ❞♦
♣r♦❜❧❡♠❛ ❡♠ q✉❡stã♦ ❡ ❛♣❧✐❝❛r ✉♠ t❡♦r❡♠❛ ❞❡ ❝♦♠♣❛r❛çã♦ ♣❛r❛ ✈❡r✐✜❝❛r q✉❡ u ≤ u✱ ♦
q✉❡ ♥♦s ♣❡r♠✐t❡ ❞❡t❡r♠✐♥❛r ✉♠❛ s♦❧✉çã♦ u t❛❧ q✉❡ u≤u≤u✳
❖s ▼ét♦❞♦s ❱❛r✐❛❝✐♦♥❛✐s s✉r❣✐r❛♠ ♥♦ sé❝✉❧♦ ❳❱■■■ ❡ ❢♦r❛♠ ❊✉❧❡r ❡ ▲❛❣r❛♥❣❡ q✉❡ ♦ tr❛♥s❢♦r♠❛r❛♠ ❡♠ ✉♠❛ t❡♦r✐❛ ♠❛t❡♠át✐❝❛ r✐❣♦r♦s❛✳ ❖ ♠ét♦❞♦ ✈❛r✐❛❝✐♦♥❛❧ ❢♦✐ ❛♣❧✐❝❛❞♦✱ ❛♣ós ❛ s✉❛ ❞❡s❝♦❜❡rt❛✱ s♦❜r❡t✉❞♦ ♥❛ ❢ís✐❝❛✱ ❡s♣❡❝✐❛❧♠❡♥t❡ ❡♠ ♠❡❝â♥✐❝❛✱ ❡ t♦r♥♦✉✲s❡ ✉♠❛ ❞✐s❝✐♣❧✐♥❛ ♠❛t❡♠át✐❝❛ ✐♥❞❡♣❡♥❞❡♥t❡✱ ❝♦♠ s❡✉s ♣ró♣r✐♦s ♠ét♦❞♦s ❞❡ ♣❡sq✉✐s❛✳ P❛r❛ ♠❛✐s ❞❡t❛❧❤❡s✱ ✈❡❥❛ ❬✹✵❪✳ ❯♠ ♠ét♦❞♦ ✈❛r✐❛❝✐♦♥❛❧ ✐♠♣♦rt❛♥t❡ ♥❛ s♦❧✉çã♦ ❞❡ ♣r♦❜❧❡♠❛s ❡❧í♣t✐❝♦s s❡♠✐❧✐♥❡❛r❡s é ❛ ❚❡♦r✐❛ ❞♦ P♦♥t♦ ❈rít✐❝♦✱ q✉❡ ❛ ❣r♦ss♦ ♠♦❞♦ ❝♦♥s✐st❡ ❡♠ ✈❡r ❝❛❞❛ s♦❧✉çã♦ ❢r❛❝❛ ❞❡ ✉♠❛ ❡q✉❛çã♦ ❞✐❢❡r❡♥❝✐❛❧ ♣❛r❝✐❛❧ ❝♦♠♦ ✉♠ ♣♦♥t♦ ❝rít✐❝♦ ❞❡ ✉♠ ❞❡t❡r♠✐♥❛❞♦ ❢✉♥❝✐♦♥❛❧✳ P♦r s✉❛ ✈❡③✱ ✉♠ ❞♦s ♣r✐♥❝✐♣❛✐s r❡s✉❧t❛❞♦s ❞❛ t❡♦r✐❛ ❞♦ P♦♥t♦ ❈rít✐❝♦✱ ❡ q✉❡ s❡rá ✉s❛❞♦ ♥❡st❡ tr❛❜❛❧❤♦✱ é ♦ ❚❡♦r❡♠❛ ❞♦ P❛ss♦ ❞❛ ▼♦♥t❛♥❤❛✱ ❞❡✈✐❞♦ ❛ ❆♠❜r♦s❡tt✐ ❡ ❘❛❜✐♥♦✇✐t③ ❬✼❪✳ ❊st❡ t❡♦r❡♠❛ ❣❛r❛♥t❡✱ s♦❜ ❤✐♣ót❡s❡s ❛❞❡q✉❛❞❛s✱ ❛ ❡①✐stê♥❝✐❛ ❞❡ ♣♦♥t♦s ❝rít✐❝♦s ❞❡ ♠✐♥✐♠❛① ♣❛r❛ ♦ ❢✉♥❝✐♦♥❛❧ ❛ss♦❝✐❛❞♦ ❛♦ ♣r♦❜❧❡♠❛ ❡st✉❞❛❞♦✳
■♥tr♦❞✉çã♦ ✺
♣❛r❛ ❡st✉❞❛r ❡①✐stê♥❝✐❛ ❞❡ s♦❧✉çã♦ ♣❛r❛ ✉♠ ♣r♦❜❧❡♠❛ ❡❧í♣t✐❝♦ s❡♠✐❧✐♥❡❛r ❝✉❥❛ ♥ã♦✲ ❧✐♥❡❛r✐❞❛❞❡ ❛♣r❡s❡♥t❛ ✉♠ t❡r♠♦ ❣r❛❞✐❡♥t❡✱ t❛♠❜é♠ ❝❤❛♠❛❞♦ ❞❡ t❡r♠♦ ❞❡ ❝♦♥✈❡❝çã♦✳
❊st❛ ❞✐ss❡rt❛çã♦ ❡stá ♦r❣❛♥✐③❛❞❛ ❞❛ s❡❣✉✐♥t❡ ❢♦r♠❛✿
◆♦ ❈❛♣ít✉❧♦ ✶✱ ❛♣r❡s❡♥t❛♠♦s ❛❧❣✉♠❛s ❞❡✜♥✐çõ❡s ❡ ♥♦çõ❡s q✉❡ ❝♦♠♣õ❡♠ ♦ ♠❡✐♦ s♦❜r❡ ♦ q✉❛❧ ❞❡s❡♥✈♦❧✈❡r❡♠♦s ♦ ♥♦ss♦ tr❛❜❛❧❤♦✳ ◆♦s ❧✐♠✐t❛♠♦s ❛ ❛♣r❡s❡♥t❛r✱ ❞❡ ♠❛♥❡✐r❛ r❡s✉♠✐❞❛✱ ❛s ♥♦çõ❡s ❢✉♥❞❛♠❡♥t❛✐s q✉❡ ❢♦r❛♠ ✉t✐❧✐③❛❞❛s✱ ❞❡ ❛❧❣✉♠❛ ❢♦r♠❛✱ ♥♦ ❞❡❝♦rr❡r ❞❡st❡ t❡①t♦✳ ❊♥✉♥❝✐❛♠♦s✱ t❛♠❜é♠✱ ❛❧❣✉♥s t❡♦r❡♠❛s ❝❧áss✐❝♦s q✉❡ ♥♦s ❛✉①✐❧✐❛rã♦ ♥❛ ♦❜t❡♥çã♦ ❞♦s r❡s✉❧t❛❞♦s ♣r✐♥❝✐♣❛✐s✳
❖s ♣ró①✐♠♦s ❞♦✐s ❝❛♣ít✉❧♦s ❞❡st❡ tr❛❜❛❧❤♦ ❛❜♦r❞❛♠✱ ❞❡ ❢♦r♠❛ ❞❡t❛❧❤❛❞❛✱ ❝♦♠♦ ♦s ♠ét♦❞♦s ❞❡ s✉❜ ❡ s✉♣❡rs♦❧✉çã♦ ❡ ✈❛r✐❛❝✐♦♥❛❧✱ r❡s♣❡❝t✐✈❛♠❡♥t❡✱ ♣♦❞❡♠ s❡r ✉t✐❧✐③❛❞♦s ♣❛r❛ ♦❜t❡r ✉♠❛ s♦❧✉çã♦ ♣❛r❛ ✉♠ ❞❡t❡r♠✐♥❛❞♦ ♣r♦❜❧❡♠❛ ❡❧í♣t✐❝♦ s❡♠✐❧✐♥❡❛r✳
◆♦ ❈❛♣ít✉❧♦ ✷✱ ❡st✉❞❛♠♦s ♦ r❡s✉❧t❛❞♦ ❞❡ ▼❛r✐✉s ●❤❡r❣✉ ❡ ❱✐❝❡♥t✐✉ ❘➔❞✉❧❡s❝✉ ❬✸✷❪✱ q✉❡ ❡♠ ✷✵✵✼ ❞❡t❡r♠✐♥❛r❛♠ ❡①✐stê♥❝✐❛ ❞❡ s♦❧✉çã♦ ♣❛r❛ ♦ ♣r♦❜❧❡♠❛
−∆u=p(x)(g(u) +f(u) +|∇u|a) ❡♠ RN,
u >0 ❡♠ RN,
u(x)−→0 q✉❛♥❞♦ |x| → ∞,
✭✶✮
♦♥❞❡ N ≥3, 0< a < 1✱ ❡ p:RN −→(0,∞) é ✉♠❛ ❢✉♥çã♦ ❍ö❧❞❡r ❝♦♥tí♥✉❛ ❞❡ ❡①♣♦❡♥t❡ 0< γ <1 t❛❧ q✉❡
(p1)
Z ∞
1
t φ(t) dt <∞✱ ♦♥❞❡ φ(r) = max
|x|=rp(x)✳
❆ss✉♠✐r❡♠♦s t❛♠❜é♠ q✉❡ g ∈C1((0,∞)) é ✉♠❛ ❢✉♥çã♦ ❞❡❝r❡s❝❡♥t❡ ❡ ♣♦s✐t✐✈❛ t❛❧ q✉❡
(g1) lim
t→0g(t) = +∞✱
❡ ❛ ❢✉♥çã♦ f : [0,∞) −→ [0,∞) é C1((0,∞))✱ ♥ã♦✲❞❡❝r❡s❝❡♥t❡ ❡ ♣♦s✐t✐✈❛ ❡♠ (0,∞) ❡
s❛t✐s❢❛③
(f1) ❛ ❢✉♥çã♦ t7−→
f(t)
t é ♥ã♦✲❝r❡s❝❡♥t❡✱ ♣❛r❛ t♦❞♦ t∈(0,∞)❀
(f2) lim
t→0+ f(t)
t = +∞ ❡ tlim→∞
f(t)
t = 0✳
❆ ✐❞❡✐❛ ❞❡s❡♥✈♦❧✈✐❞❛ ❡♠ ❬✸✷❪ ❝♦♥s✐st❡ ❡♠ ❛♣❧✐❝❛r ♦ ♠ét♦❞♦ ❞❡ s✉❜ ❡ s✉♣❡rs♦❧✉çã♦ ♣❛r❛ ♦
♣r♦❜❧❡♠❛
−∆u=p(x)(g(u) +f(u) +|∇u|a) ❡♠ Ω,
u >0 ❡♠ Ω,
u(x) = 0 s♦❜r❡ ∂Ω,
■♥tr♦❞✉çã♦ ✻
♦ q✉❡ ♥♦s ♣❡r♠✐t❡ ❣❡r❛r ✉♠❛ s❡q✉ê♥❝✐❛ ♠♦♥ót♦♥❛ ❞❡ s♦❧✉çõ❡s (un) ♣❛r❛ ❛ ❢❛♠í❧✐❛ ❞❡ ♣r♦❜❧❡♠❛s ❞♦ t✐♣♦ (2)✱ s♦❜r❡ Bn✱ ❧✐♠✐t❛❞❛ t❛♥t♦ s✉♣❡r✐♦r q✉❛♥t♦ ✐♥❢❡r✐♦r♠❡♥t❡✳ ❆ss✐♠✱
♣♦r ✉♠ ♣r♦❝❡❞✐♠❡♥t♦ ♣❛❞rã♦✱ ♣♦❞❡♠♦s ❝♦♥❝❧✉✐r q✉❡ (un) ♣♦ss✉✐ ✉♠❛ s✉❜s❡q✉ê♥❝✐❛ q✉❡ ❝♦♥✈❡r❣❡ ✉♥✐❢♦r♠❡♠❡♥t❡ ❛ ✉♠❛ ❢✉♥çã♦ ❡♠ C2,α(Ω)✳ P♦st❡r✐♦r♠❡♥t❡✱ ♣♦r ✉♠ ♣r♦❝❡ss♦ ❞✐❛❣♦♥❛❧✱ s❡❣✉❡ q✉❡ (un) ♣♦ss✉✐ ✉♠❛ s✉❜s❡q✉ê♥❝✐❛ q✉❡ ❝♦♥✈❡r❣❡ ✉♥✐❢♦r♠❡♠❡♥t❡ s♦❜r❡ s✉❜❝♦♥❥✉♥t♦s ❛❜❡rt♦s ❧✐♠✐t❛❞♦s ❞❡ RN ❛ ✉♠❛ ❢✉♥çã♦ u ∈ C2,α
loc(R
N)✱ q✉❡ é s♦❧✉çã♦ ❞♦
♣r♦❜❧❡♠❛ (1)✳ ❚❛❧ ♣r♦❝❡❞✐♠❡♥t♦ s❡rá ✉t✐❧✐③❛❞♦ ♣❛r❛ ❞❡♠♦♥str❛r♠♦s ♦ r❡s✉❧t❛❞♦ ♣r✐♥❝✐♣❛❧
❞♦ ❈❛♣ít✉❧♦ ✷✱ ❛ s❛❜❡r✿
❚❡♦r❡♠❛ ✵✳✶✳ ❙✉♣♦♥❤❛ q✉❡ (f1)✱ (f2)✱ (g1) ❡ (p1) s❡❥❛♠ s❛t✐s❢❡✐t❛s✳ ❊♥tã♦ ♦ ♣r♦❜❧❡♠❛
(1) t❡♠ ♣❡❧♦ ♠❡♥♦s ✉♠❛ s♦❧✉çã♦ ❡♠ Cloc2,α(RN)✳
➱ ✐♠♣♦rt❛♥t❡ ♠❡♥❝✐♦♥❛r q✉❡ ❛ ❡q✉❛çã♦ (1) é ❞♦ t✐♣♦ ▲❛♥❡✲❊♠❞❡♥✲❋♦✇❧❡r✳ ❊q✉❛çõ❡s
❞❡st❡ t✐♣♦ s❡ ♦r✐❣✐♥❛r❛♠ ❛ ♣❛rt✐r ❞❡ t❡♦r✐❛s s♦❜r❡ ❛ ❞✐♥â♠✐❝❛ ❞❡ ❣❛s❡s ❡♠ ❛str♦❢ís✐❝❛ ✭✈❡❥❛ ❬✷✷❪✮✱ s✉r❣✐♥❞♦ t❛♠❜é♠ ♥♦ ❡st✉❞♦ ❞❛ ♠❡❝â♥✐❝❛ ❞♦s ✢✉✐❞♦s✱ ♠❡❝â♥✐❝❛ r❡❧❛t✐✈íst✐❝❛✱ ❢ís✐❝❛ ♥✉❝❧❡❛r ❡ ♥♦ ❡st✉❞♦ ❞❛ q✉í♠✐❝❛✳ P❛r❛ ✉♠❛ ❛❜♦r❞❛❣❡♠ ♠❛✐s ❞❡t❛❧❤❛❞❛ ❞❡st❡ t✐♣♦ ❞❡ ❡q✉❛çõ❡s✱ r❡❢❡r✐♠♦s ❛♦ ❧❡✐t♦r ♦ tr❛❜❛❧❤♦ ❞❡ ❲♦♥❣ ❬✹✾❪✳ ❆ ❡q✉❛çã♦ ❞❡ ▲❛♥❡✲❊♠❞❡♥✲ ❋♦✇❧❡r t❡♠ s✐❞♦ ❡st✉❞❛❞❛ ♣♦r ♠✉✐t♦s ❛✉t♦r❡s q✉❡ ✉t✐❧✐③❛♠ ✈ár✐♦s ♠ét♦❞♦s ❡ té❝♥✐❝❛s✳ ❊♥tr❡ ❡❧❛s✱ ❝✐t❛♠♦s ❛ t❡♦r✐❛ ❞♦ ♣♦♥t♦ ❝rít✐❝♦✱ ❛ t❡♦r✐❛ ❞♦ ♣♦♥t♦ ✜①♦ ❡ ❛ t❡♦r✐❛ ❞♦ ❣r❛✉ t♦♣♦❧ó❣✐❝♦✳ P❛r❛ ♠❛✐♦r❡s ❞❡t❛❧❤❡s✱ ✈❡❥❛ ❬✷✱ ✺✱ ✸✸✱ ✸✼✱ ✸✾❪✳
❋✉♥çõ❡s q✉❡ s❛t✐s❢❛③❡♠ ✉♠❛ ❝♦♥❞✐çã♦ ❝♦♠♦ (g1) sã♦ ❞✐t❛s s✐♥❣✉❧❛r❡s✳ Pr♦❜❧❡♠❛s
❡♥✈♦❧✈❡♥❞♦ ♥ã♦✲❧✐♥❡❛r✐❞❛❞❡s s✐♥❣✉❧❛r❡s s✉r❣❡♠ ❡♠ ✈ár✐❛s s✐t✉❛çõ❡s ❢ís✐❝❛s✱ ♣r❡s❡♥t❡s ♥❛ ❝♦♥❞✉t✐✈✐❞❛❞❡ ❡❧étr✐❝❛ ✭❋✉❧❦s ❡ ▼❛②❜❡❡✱ ✶✾✻✵ ❬✷✸❪✮✱ ♥❛ t❡♦r✐❛ ❞♦s ✢✉✐❞♦s ♣s❡✉❞♦♣❧ást✐❝♦s ✭❈❛❧❧❡❣❛r✐ ❡ ◆❛s❤♠❛♥✱ ✶✾✽✵ ❬✶✵❪✮✱ ❡♠ s✉♣❡r❢í❝✐❡s ♠í♥✐♠❛s s✐♥❣✉❧❛r❡s ✭❈❛✛❛r❡❧❧✐✱ ❍❛r❞t ❡ ❙✐♠♦♥✱ ✶✾✽✹ ❬✾❪✮✱ ❡♠ ♣r♦❝❡ss♦s ❞❡ r❡❛çã♦✲❞✐❢✉sã♦✱ ♥❛ ♦❜t❡♥çã♦ ❞❡ ❞✐✈❡rs♦s í♥❞✐❝❡s ❣❡♦❢ís✐❝♦s ❡ ❡♠ ♣r♦❝❡ss♦s ✐♥❞✉str✐❛✐s✱ ❡♥tr❡ ♦✉tr♦s✳
❊♠ r❡❧❛çã♦ ❛ s♦❧✉çõ❡s ❣r♦✉♥❞ st❛t❡ ♣❛r❛ ❡q✉❛çõ❡s ❡❧í♣t✐❝❛s s✐♥❣✉❧❛r❡s✱ ✐st♦ é✱ s♦❧✉çõ❡s ♣♦s✐t✐✈❛s ❞❡✜♥✐❞❛s ❡♠ t♦❞♦ ♦ ❡s♣❛ç♦ ❡ t❡♥❞❡♥❞♦ ❛ ③❡r♦ ♥♦ ✐♥✜♥✐t♦✱ ❡①✐st❡♠ ♠✉✐t♦s tr❛❜❛❧❤♦s✱ ♣r✐♥❝✐♣❛❧♠❡♥t❡ q✉❛♥❞♦ ❛ ♥ã♦✲❧✐♥❡❛r✐❞❛❞❡ ♥ã♦ ❛♣r❡s❡♥t❛ ❞❡♣❡♥❞ê♥❝✐❛ ❞♦ ❣r❛❞✐❡♥t❡ ❞❛ s♦❧✉çã♦✳ ❊♥tr❡ ❡❧❡s✱ ✐♥✐❝✐❛♠♦s ❝✐t❛♥❞♦ ♦s q✉❡ ❞❡t❡r♠✐♥❛r❛♠ ❛ ❡①✐stê♥❝✐❛ ❞❡ ♣❡❧♦ ♠❡♥♦s ✉♠❛ s♦❧✉çã♦ u∈Cloc2,α(RN)♣❛r❛ ♦ s❡❣✉✐♥t❡ ♣r♦❜❧❡♠❛
−∆u=p(x)g(u) ❡♠ RN,
u >0 ❡♠ RN,
u(x)−→0 q✉❛♥❞♦ |x| → ∞,
■♥tr♦❞✉çã♦ ✼
♦♥❞❡ p:RN −→(0,∞) é ✉♠❛ ❢✉♥çã♦ ❧♦❝❛❧♠❡♥t❡ ❍ö❧❞❡r ❝♦♥tí♥✉❛ q✉❡ s❛t✐s❢❛③
Z ∞
0
tψ(t)dt <∞, s❡♥❞♦ ψ(t) = max{p(x) :|x|=t}, t >0,
❡ g ∈C1((0,∞),(0,∞)) s❛t✐s❢❛③ ♣❡❧♦ ♠❡♥♦s ❞✉❛s ❞❛s s❡❣✉✐♥t❡s ❝♦♥❞✐çõ❡s✿
(g1) g é ♥ã♦✲❝r❡s❝❡♥t❡✱ (g2) lim
t→0+g(t) = ∞✱
(g3) g é ❧✐♠✐t❛❞❛ ♣❛r❛ t s✉✜❝✐❡♥t❡♠❡♥t❡ ❣r❛♥❞❡✱ (g4) lim
t→0+ g(t)
t =∞,
(g5)
g(t)
t+c é ❞❡❝r❡s❝❡♥t❡ ♣❛r❛ ❛❧❣✉♠❛ ❝♦♥st❛♥t❡ c≥0✱ (g6) limt→∞
g(t)
t = 0✳
P♦r ❡①❡♠♣❧♦✱ ▲❛✐r ❡ ❙❤❛❦❡r ❬✸✺❪ ❡♠ ✶✾✾✻ ❡ ❩❤❛♥❣ ❬✺✺❪ ❡♠ ✶✾✾✼ ♠♦str❛r❛♠ q✉❡ ♦ ♣r♦❜❧❡♠❛
(3) ❛❞♠✐t❡ s♦❧✉çã♦ s❡g s❛t✐s❢❛③(g1)❡(g2)✳ ❊♠ ✶✾✾✾✱ ❈îrst❡❛ ❡ ❘➔❞✉❧❡s❝✉ ❬✶✶❪ ♠♦str❛r❛♠
q✉❡ ♦ ♣r♦❜❧❡♠❛ (3) ❛❞♠✐t❡ s♦❧✉çã♦ q✉❛♥❞♦ g ♥ã♦ é ♥❡❝❡ss❛r✐❛♠❡♥t❡ ♠♦♥ót♦♥❛✱ ♣♦ré♠
s❛t✐s❢❛③ ❛s ❝♦♥❞✐çõ❡s (g3), (g4)❡ (g5)✱ ❝♦♠ c >0✳ ❊♠ ❬✷✶❪✱ ❋❡♥❣ ❡ ▲✐✉ ❡st❛❜❡❧❡❝❡r❛♠✱ ❡♠
✷✵✵✹✱ ❛ ❡①✐stê♥❝✐❛ ❞❡ ✉♠❛ s♦❧✉çã♦ ❣r♦✉♥❞ st❛t❡ ♣❛r❛ ♦ ♣r♦❜❧❡♠❛(3) q✉❛♥❞♦ ❣ s❛t✐s❢❛③ ❛s
❝♦♥❞✐çõ❡s(g2)❡(g3)✳ ❊♠ ✷✵✵✻✱ ●♦♥ç❛❧✈❡s ❡ ❙❛♥t♦s ❬✷✽❪ ❡st❛❜❡❧❡❝❡r❛♠ ❛ ❡①✐stê♥❝✐❛ ❞❡ ✉♠❛
s♦❧✉çã♦ ♣❛r❛ (3) s♦❜ ❛ ❤✐♣ót❡s❡ q✉❡ g s❛t✐s❢❛③ (g4), (g5) ❡ (g6)✱ ❝♦♠ c = 0✳ ❋✐♥❛❧♠❡♥t❡
❩❤❛♥❣ ❬✺✻❪ ♠♦str♦✉✱ ❡♠ ✷✵✵✼✱ q✉❡(3) t❡♠ s♦❧✉çã♦ s♦❜ ❛ ❝♦♥❞✐çã♦ q✉❡ ❣ s❛t✐s❢❛ç❛ s♦♠❡♥t❡ (g4)❡ (g6)✳ P❛r❛ ♠❛✐♦r❡s ❞❡t❛❧❤❡s✱ r❡❢❡r✐♠♦s ❛♦ ❧❡✐t♦r ♦s tr❛❜❛❧❤♦s ❬✸✽✱ ✸✵✱ ✹✷❪✳
Pr♦❜❧❡♠❛s ❡♠ q✉❡ ❛ ♥ã♦✲❧✐♥❡❛r✐❞❛❞❡ t❡♠ ✉♠ t❡r♠♦ ❣r❛❞✐❡♥t❡ ✭♦✉ ❝♦♥✈❡❝t✐✈♦✮ s✉r❣❡♠ ❡♠ t❡♦r✐❛ ❞❡ ❝♦♥tr♦❧❡ ❡st♦❝ást✐❝♦ ✭▲❛sr② ❡ ▲✐♦♥s✱ ✶✾✽✾ ❬✸✻❪✮✱ ♥♦ ❡st✉❞♦ ❞❡ ✉♠ ❝❛♠♣♦ ❡❧❡tr♦♠❛❣♥ét✐❝♦ ✭❙t✉❛rt✱ ✶✾✾✶ ❬✹✹❪✱ ❙t✉❛rt ❡ ❩❤♦✉✱ ✶✾✾✻ ❬✹✺❪✮✱ ❡♠ ✉♠ ♠❡✐♦ ♥ã♦✲❧✐♥❡❛r✱ ❡♥tr❡ ♦✉tr♦s✳
❈♦♠ r❡❧❛çã♦ ❛ ♣r♦❜❧❡♠❛s ❡♥✈♦❧✈❡♥❞♦ t❡r♠♦ ❞❡ ❝♦♥✈❡❝çã♦✱ ♣♦❞❡♠♦s ❝✐t❛r ❉✐♥✉ ❬✶✺❪✱ q✉❡ ❡♠ ✷✵✵✸ ❣❛r❛♥t✐✉ ❛ ❡①✐stê♥❝✐❛ ❞❡ ✉♠❛ ú♥✐❝❛ s♦❧✉çã♦ ❝❧áss✐❝❛ ♣❛r❛ ♦ ♣r♦❜❧❡♠❛
−∆u+q(x)|∇u|a =p(x)u−γ ❡♠ RN,
u >0 ❡♠ RN,
u(x)−→0 q✉❛♥❞♦ |x| → ∞,
✭✹✮
♦♥❞❡ N ≥3, a, γ >0 ❡p, q ∈Cloc0,α(RN) sã♦ t❛✐s q✉❡ p >0, q≥0 ❡
Z ∞
0
rΦ(r)dr <∞, ♦♥❞❡ Φ(r) = max
|x|=rp(x).
■♥tr♦❞✉çã♦ ✽
❡①✐stê♥❝✐❛ ❞❡ s♦❧✉çã♦ ♣❛r❛ ♦ ♣r♦❜❧❡♠❛ (1)✱ r❡❧❛t❛❞♦ ❛♥t❡r✐♦r♠❡♥t❡✳ ❆✐♥❞❛ ❡♠ ✷✵✵✼✱ ❡st❡
tr❛❜❛❧❤♦ ❢♦✐ ♠❡❧❤♦r❛❞♦ ♣♦r ❳✉❡ ❡ ❩❤❛♥❣ ❬✺✶❪✱ q✉❡ ❝♦♥s✐❞❡r❛r❛♠ (1) s❡♠ ❡①✐❣✐r q✉❛❧q✉❡r
♠♦♥♦t♦♥✐❝✐❞❛❞❡ s♦❜r❡ g ❡ f ✱ ♠❛s s✉♣♦♥❞♦
lim
s→0+ g(s)
s =∞, slim→∞
g(s)
s = 0, slim→0+ f(s)
s =∞ e slim→∞
f(s)
s = 0.
P♦st❡r✐♦r♠❡♥t❡✱ ❳✉❡ ❡ ❙❤❛♦ ❬✺✷✱ ✺✸❪ ♠❡❧❤♦r❛r❛♠ ♦ tr❛❜❛❧❤♦ ❞❡ ❉✐♥✉ ❝♦♥s✐❞❡r❛♥❞♦p(x)g(u)
❡ f(x, u)✱ r❡s♣❡❝t✐✈❛♠❡♥t❡✱ ❡♠ ✈❡③ ❞❡ p(x)u−γ ❡♠ (4)✱ s♦❜ ❝♦♥❞✐çõ❡s ❛❞❡q✉❛❞❛s ♣❛r❛ g ❡
f✳
●♦♥ç❛❧✈❡s ❡ ❙✐❧✈❛✱ ❬✷✾❪ ❡♠ ✷✵✶✵✱ tr❛❜❛❧❤❛r❛♠ r❡s✉❧t❛❞♦s ❞❡ ❡①✐stê♥❝✐❛ ❡ ♥ã♦ ❡①✐stê♥❝✐❛ ❞❡ s♦❧✉çã♦ ♣❛r❛ ♦ ♣r♦❜❧❡♠❛
−∆u=λp(x)(g(u) +|∇u|a) ❡♠ RN,
u >0 ❡♠ RN,
u(x)−→0 q✉❛♥❞♦ |x| → ∞,
(P+)
♦♥❞❡ N ≥3, 0< a <1 ❡ λ >0 é ✉♠ ♣❛râ♠❡tr♦✱ p :RN −→(0,∞) é ❧♦❝❛❧♠❡♥t❡ ❍ö❧❞❡r ❝♦♥tí♥✉❛ ❡ s❛t✐s❢❛③ Z ∞
0
tφ(t)dt < ∞ ♦✉
Z ∞
0
tφ(t)dt=∞,
♦♥❞❡ φ(r) = max
|x|=rp(x), r≥0✳ ❆❧é♠ ❞✐ss♦✱ g : (0,∞)−→(0,∞)é C
1 ❡ s❛t✐s❢❛③
lim
s→0+ g(s)
s =ρ0, slim→∞
g(s)
s =ρ∞, ♦♥❞❡ ρ0 ∈(0,∞] ❡ ρ∞ ∈[0,∞].
P❛r❛ ♦ ❝❛s♦ ❡♠ q✉❡ r6= 2✱ ❲✉ ❡ ❨❛♥❣ ❬✺✵❪✱ ❡♠ ✷✵✶✵✱ ♠♦str❛r❛♠ ❛ ♥ã♦ ❡①✐stê♥❝✐❛ ❞❡ ✉♠❛
s♦❧✉çã♦ r❛❞✐❛❧♠❡♥t❡ s✐♠étr✐❝❛ ♣❛r❛ ♦ ♣r♦❜❧❡♠❛
−div(|∇u|r−2∇u) =p(x)(g(u) +f(u) +|∇u|a) ❡♠ RN,
u >0 ❡♠ RN,
u(x)−→0 q✉❛♥❞♦ |x| → ∞,
♦♥❞❡ p ❡ f sã♦ ❢✉♥çõ❡s r❛❞✐❛✐s✱ f ∈ Cloc0,α((0,∞),(0,∞))✱ N ≥ 3✱ a ≥ 0✱ g ∈
C1((0,∞),(0,∞))❡ s✉❜❧✐♥❡❛r ♥❛ ♦r✐❣❡♠ ❡ ♥♦ ✐♥✜♥✐t♦✳
■♥tr♦❞✉çã♦ ✾
s♦❧✉çã♦ u∈C1(RN)∩C2(RN \ {0})r❛❞✐❛❧♠❡♥t❡ s✐♠étr✐❝❛ ♣❛r❛ ♦ ♣r♦❜❧❡♠❛
−div(|∇u|r−2∇u) +b(x)|∇u|p−1 =a(u)f(u) ❡♠ RN,
u >0 ❡♠ RN,
u(x)−→0 q✉❛♥❞♦ |x| → ∞,
♦♥❞❡ N ≥3✱ 1< r < N✱ a✱ b:RN −→(0,∞) sã♦ ❢✉♥çõ❡s r❛❞✐❛✐s ❝♦♥tí♥✉❛s ❡a s❛t✐s❢❛③
Z ∞
0
sr−11a(s)r−11ds <∞, s❡ 1< r≤2,
Z ∞
0
s(r
−2)N+1
r−1 a(s)ds <∞, s❡ 2≤r < N,
s❡♥❞♦ f : (0,∞)−→(0,∞) ❞❡ ❝❧❛ss❡C1✱ s✐♥❣✉❧❛r ♥♦ ③❡r♦✱ lim
s→∞f(s)/s
r−1 = 0 ❡ ❛ ❢✉♥çã♦
s 7−→f(s)/sr−1 é ♥ã♦ ❝r❡s❝❡♥t❡ ❡♠ (0,∞)✳
◆♦ ❈❛♣ít✉❧♦ ✸ ❞❡st❡ tr❛❜❛❧❤♦ ❛♣r❡s❡♥t❛♠♦s ✉♠ r❡s✉❧t❛❞♦ ♣✐♦♥❡✐r♦ ❞❡✈✐❞♦ ❛ ❉❥❛✐r♦ ❞❡ ❋✐❣✉❡✐r❡❞♦✱ ▼❛r✐♦ ●✐r❛r❞✐ ❡ ▼✐❝❤❡❧❡ ▼❛t③❡✉ ❬✶✻❪✱ q✉❡ ❡♠ ✷✵✵✹ ❝♦♥s✐❞❡r❛r❛♠ ❛ s♦❧✉❜✐❧✐❞❛❞❡
❞♦ ♣r♦❜❧❡♠❛ (
−∆u=f(x, u,∇u) ❡♠ Ω,
u= 0 s♦❜r❡ ∂Ω, ✭✺✮
♦♥❞❡ Ω é ✉♠ ❞♦♠í♥✐♦ s✉❛✈❡ ❧✐♠✐t❛❞♦ ❡♠ RN, N ≥ 3✳ ❊st❡ t✐♣♦ ❞❡ ❡q✉❛çõ❡s ♥ã♦ t❡♠
s✐❞♦ ❡①t❡♥s✐✈❛♠❡♥t❡ ❡st✉❞❛❞♦ ♣♦r ♠ét♦❞♦s ✈❛r✐❛❝✐♦♥❛✐s ❝♦♠♦ ♥♦ ❝❛s♦ ❡♠ q✉❡ ♥ã♦ ❡①✐st❡ ❛ ♣r❡s❡♥ç❛ ❞♦ ❣r❛❞✐❡♥t❡✳ ❆ r❛③ã♦ é q✉❡✱ ❝♦♥tr❛r✐❛♠❡♥t❡ ❛♦ ú❧t✐♠♦ ❝❛s♦✱ ❛ ❡q✉❛çã♦ ❡♠
(5) ♥ã♦ é ✈❛r✐❛❝✐♦♥❛❧✳ ❆ss✐♠✱ ❛ t❡♦r✐❛ ❞♦ ♣♦♥t♦ ❝rít✐❝♦ ♥ã♦ é ❛❞❡q✉❛❞❛ ♣❛r❛ ✉♠ ❛t❛q✉❡
❞✐r❡✐t♦ ❛♦ ♣r♦❜❧❡♠❛✳ ❆ té❝♥✐❝❛ ✉s❛❞❛ ♥❡st❡ tr❛❜❛❧❤♦ ❝♦♥s✐st❡ ❡♠ ❛ss♦❝✐❛r✱ ❛♦ ♣r♦❜❧❡♠❛
(5)✱ ♦ s❡❣✉✐♥t❡ ♣r♦❜❧❡♠❛
(
−∆u=f(x, u,∇ω) ❡♠ Ω,
u= 0 s♦❜r❡ ∂Ω, ✭✻✮
♦♥❞❡ ω ∈H1
0(Ω) ♥ã♦ ❞❡♣❡♥❞❡ ❞❡u✳
❆❣♦r❛ ♦ ♣r♦❜❧❡♠❛ (6) é ✈❛r✐❛❝✐♦♥❛❧ ❡ ♣♦❞❡♠♦s tr❛tá✲❧♦ ♣♦r ♠ét♦❞♦s ✈❛r✐❛❝✐♦♥❛✐s✳
❊s♣❡❝✐✜❝❛♠❡♥t❡✱ ✉t✐❧✐③❛r❡♠♦s ❛ té❝♥✐❝❛ ❞♦ P❛ss♦ ❞❛ ▼♦♥t❛♥❤❛ ♣❛r❛ ❛❜♦r❞❛r ♦ ♣r♦❜❧❡♠❛
(6)✳ P❛r❛ ❡st❡ ✜♠✱ ❛tr✐❜✉✐r❡♠♦s ❤✐♣ót❡s❡s s♦❜r❡f ❞❡ t❛❧ ❢♦r♠❛ q✉❡ ♦ ♣r♦❜❧❡♠❛ (6) ♣♦ss❛
s❡r tr❛t❛❞♦ ♣❡❧♦ ❚❡♦r❡♠❛ ❞♦ P❛ss♦ ❞❛ ▼♦♥t❛♥❤❛ ❞❡ ❆♠❜r♦s❡tt✐ ❡ ❘❛❜✐♥♦✇✐t③ ❬✼❪✳ ◆♦ss♦ ♣r✐♠❡✐r♦ ❝♦♥❥✉♥t♦ ❞❡ ❤✐♣ót❡s❡s s♦❜r❡ ❛ ♥ã♦ ❧✐♥❡❛r✐❞❛❞❡ f é ♦ s❡❣✉✐♥t❡✿
■♥tr♦❞✉çã♦ ✶✵
✭f1✮ lim
t→0
f(x, t, ξ)
t = 0 ✉♥✐❢♦r♠❡♠❡♥t❡✱ ♣❛r❛ x∈Ω, ξ ∈R
N❀
✭f2✮ ❡①✐st❡♠ ❝♦♥st❛♥t❡s a1 >0❡ p∈(1,NN+2−2) t❛✐s q✉❡
|f(x, t, ξ)| ≤a1(1 +|t|p), ♣❛r❛ t♦❞♦sx∈Ω, t∈R, ξ ∈RN;
✭f3✮ ❡①✐st❡♠ ❝♦♥st❛♥t❡s θ >2 ❡t0 >0 t❛✐s q✉❡
0< θF(x, t, ξ)≤tf(x, t, ξ), ♣❛r❛ t♦❞♦sx∈Ω, |t| ≥t0, ξ ∈RN,
♦♥❞❡
F(x, t, ξ) =
Z t
0
f(x, s, ξ)ds;
✭f4✮ ❡①✐st❡♠ ❝♦♥st❛♥t❡s a2, a3 >0t❛✐s q✉❡
F(x, t, ξ)≥a2|t|θ−a3, ♣❛r❛ t♦❞♦sx∈Ω, t∈R, ξ ∈RN.
❙♦❜ ❡st❡ ❝♦♥❥✉♥t♦ ❞❡ ❤✐♣ót❡s❡s✱ ♣♦❞❡♠♦s ✉t✐❧✐③❛r ♦ ❚❡♦r❡♠❛ ❞♦ P❛ss♦ ❞❛ ▼♦♥t❛♥❤❛ ♣❛r❛ ♠♦str❛r ♦ s❡❣✉✐♥t❡ r❡s✉❧t❛❞♦✿
❚❡♦r❡♠❛ ✵✳✷✳ ❙✉♣♦♥❤❛ q✉❡ (f0)−(f4) s❡❥❛♠ s❛t✐s❢❡✐t❛s✳ ❊♥tã♦ ❡①✐st❡♠ ❝♦♥st❛♥t❡s
♣♦s✐t✐✈❛s c1 ❡ c2 t❛✐s q✉❡✱ ♣❛r❛ ❝❛❞❛ ω∈H01(Ω)✱ ♦ ♣r♦❜❧❡♠❛ (6) t❡♠ ✉♠❛ s♦❧✉çã♦ ❢r❛❝❛ uω t❛❧ q✉❡
c1 ≤ kuωk ≤c2.
❆❧é♠ ❞✐ss♦✱ (6) ♣♦ss✉✐ ♣❡❧♦ ♠❡♥♦s ✉♠❛ s♦❧✉çã♦ ♣♦s✐t✐✈❛ ❡ ✉♠❛ s♦❧✉çã♦ ♥❡❣❛t✐✈❛✳
P❛r❛ ♦❜t❡r ✉♠❛ s♦❧✉çã♦ ♣❛r❛ ♦ ♣r♦❜❧❡♠❛(5)✱ é ♥❡❝❡ssár✐♦ ❛❞✐❝✐♦♥❛r ❛ s❡❣✉✐♥t❡ ❤✐♣ót❡s❡✿ (f5) ❛ ❢✉♥çã♦f s❛t✐s❢❛③ ❛s s❡❣✉✐♥t❡s ❝♦♥❞✐çõ❡s ▲✐♣s❝❤✐t③ ❧♦❝❛✐s✿
(i) |f(x, t′
, ξ)−f(x, t′′
, ξ)| ≤L1 |t
′
−t′′
|, ♣❛r❛ t♦❞♦s x∈Ω, t′
, t′′
∈[0, ρ1], |ξ| ≤ρ2✱
(ii) |f(x, t, ξ′
)−f(x, t, ξ′′
)| ≤L2|ξ
′
−ξ′′
|, ♣❛r❛ t♦❞♦sx∈Ω, t∈[0, ρ1], |ξ
′
|, |ξ′′
| ≤ρ2✱
♦♥❞❡ρ1 ❡ρ2❞❡♣❡♥❞❡♠ ❡①♣❧✐❝✐t❛♠❡♥t❡ ❞❡p✱N✱θ✱a1✱a2✱a3 ❞❛❞♦s ♥❛s ❤✐♣ót❡s❡s ❛♥t❡r✐♦r❡s✳
❖ ❚❡♦r❡♠❛ ✵✳✷ ♥♦s ❣❛r❛♥t❡ ❛ ❡①✐stê♥❝✐❛ ❞❡ ✉♠❛ s❡q✉ê♥❝✐❛(un)⊂H01(Ω) ❞❡ s♦❧✉çõ❡s ♣❛r❛ ❛ ❢❛♠í❧✐❛ ❞❡ ♣r♦❜❧❡♠❛s
(
−∆un =f(x, un,∇un−1) ❡♠ Ω,
■♥tr♦❞✉çã♦ ✶✶
♦ q✉❡ ♥♦s ♣❡r♠✐t❡✱ ♠❡❞✐❛♥t❡ ✉♠ ♣r♦❝❡❞✐♠❡♥t♦ ♣❛❞rã♦✱ ♠♦str❛r q✉❡ ❡①✐st❡ u ∈ H01(Ω)
♣♦s✐t✐✈❛ s❛t✐s❢❛③❡♥❞♦ ♦ ♣r♦❜❧❡♠❛(5)✳ ▼❡❞✐❛♥t❡ ✉♠ ❛r❣✉♠❡♥t♦ ❜♦♦tstr❛♣✱ ♠♦str❛♠♦s q✉❡
u∈C2,α(Ω)✱ ✐st♦ é✱ ♠♦str❛♠♦s ♦ r❡s✉❧t❛❞♦ ♣r✐♥❝✐♣❛❧ ❞♦ ❈❛♣ít✉❧♦ ✸✱ ❛ s❛❜❡r✿
❚❡♦r❡♠❛ ✵✳✸✳ ❙✉♣♦♥❤❛ q✉❡ ❛s ❝♦♥❞✐çõ❡s (f0)−(f5) s❡❥❛♠ ✈á❧✐❞❛s✳ ❊♥tã♦ ♦ ♣r♦❜❧❡♠❛(5)
t❡♠ ✉♠❛ s♦❧✉çã♦ ♣♦s✐t✐✈❛ ❡ ✉♠❛ s♦❧✉çã♦ ♥❡❣❛t✐✈❛✱ ❞❡s❞❡ q✉❡
λ−11L1+λ
−12
1 L2 <1,
♦♥❞❡ λ1 é ♦ ♣r✐♠❡✐r♦ ❛✉t♦✈❛❧♦r ❞❡ (−∆, H01(Ω))✳ ❆❧é♠ ❞✐ss♦✱ ❛ s♦❧✉çã♦ ♦❜t✐❞❛ é ❞❡ ❝❧❛ss❡
C2✳
❱ár✐♦s tr❛❜❛❧❤♦s tr❛t❛♠ ♦ ♣r♦❜❧❡♠❛(5)✉s❛♥❞♦ s✉❜ ❡ s✉♣❡rs♦❧✉çã♦✱ ♦ ❣r❛✉ t♦♣♦❧ó❣✐❝♦✱
t❡♦r❡♠❛s ❞❡ ♣♦♥t♦ ✜①♦ ❡ ♠ét♦❞♦ ❞❡ ●❛❧❡r❦✐♥✳ ❱❡❥❛✱ ♣♦r ❡①❡♠♣❧♦✱ ❬✸✱ ✹✱ ✶✽✱ ✹✶✱ ✺✹❪✳ ❊♠ ❬✶✻❪ ♦s ❛✉t♦r❡s ❞❡s❡♥✈♦❧✈❡r❛♠ ✉♠ ♠ét♦❞♦ ❝♦♠♣❧❡t❛♠❡♥t❡ ❞✐❢❡r❡♥t❡ ❞❡ t✐♣♦ ✈❛r✐❛❝✐♦♥❛❧✳ ❈♦♠ ❜❛s❡ ♥❛ s✉♣♦s✐çã♦ q✉❡ f t❡♠ ✉♠ ❝r❡s❝✐♠❡♥t♦ s✉❜❝rít✐❝♦ ❝♦♠ ✉♠ ❝♦♠♣♦rt❛♠❡♥t♦
s✉♣❡r❧✐♥❡❛r ♥❛ ♦r✐❣❡♠ ❡ ♥♦ ✐♥✜♥✐t♦ ❝♦♠ r❡s♣❡✐t♦ à s❡❣✉♥❞❛ ✈❛r✐á✈❡❧✱ ♦❜t✐✈❡r❛♠ ❛ ❡①✐stê♥❝✐❛ ❞❡ ✉♠❛ s♦❧✉çã♦ ♣♦s✐t✐✈❛ ❡ ✉♠❛ s♦❧✉çã♦ ♥❡❣❛t✐✈❛ ♣❛r❛ ♦ ♣r♦❜❧❡♠❛ (5)✱ ✉s❛♥❞♦ ♦ ❚❡♦r❡♠❛
❞♦ P❛ss♦ ❞❛ ▼♦♥t❛♥❤❛ ❡ ✉♠❛ té❝♥✐❝❛ ✐t❡r❛t✐✈❛✳
❆ ♠❡s♠❛ ✐❞❡✐❛ ❞❡ ❬✶✻❪ ❢♦✐ ✉t✐❧✐③❛❞❛✱ ❛✐♥❞❛ ♥♦ ❛♥♦ 2004✱ ♣♦r ●✐r❛r❞✐ ❡ ▼❛t③❡✉ ❬✷✻❪✱
q✉❡ ❡st✉❞❛r❛♠ ♦ ♠❡s♠♦ ♣r♦❜❧❡♠❛ (5) s✉♣♦♥❞♦ q✉❡f s❛t✐s❢❛③ (f0),(f1)✱(f3)−(f5)❝♦♠ ❛
❤✐♣ót❡s❡ ❛❞✐❝✐♦♥❛❧✿
( ˜f2) ❡①✐st❡♠ ❝♦♥st❛♥t❡s a1 >0❡ p∈(1,NN+2−2), r∈(0,1)t❛✐s q✉❡
|f(x, t, ξ)| ≤a1(1 +|t|p)(1 +|ξ|r), ♣❛r❛ t♦❞♦sx∈Ω, t∈R, ξ ∈RN.
◆❛ ❛♣❧✐❝❛çã♦ ❞❛ té❝♥✐❝❛✱ ❛ ♥♦✈✐❞❛❞❡ ❞❡st❡ tr❛❜❛❧❤♦ ❝♦♥s✐st❡ ❡♠ ❝♦♥s✐❞❡r❛r ✉♠ ❝♦♥✈❡♥✐❡♥t❡ tr✉♥❝❛♠❡♥t♦ ❞❛ ❢✉♥çã♦ f✱ ♣❛r❛ ♦ q✉❛❧ ♥ã♦ ❤á ❞❡♣❡♥❞ê♥❝✐❛ ❞♦ ❣r❛❞✐❡♥t❡ ♥♦ ✐♥✜♥✐t♦✳
❘❡❢❡r✐♠♦s ❛✐♥❞❛✱ ❛♦ ❧❡✐t♦r✱ ♦s tr❛❜❛❧❤♦s ❬✷✺✱ ✷✼❪ ❞♦s ♠❡s♠♦s ❛✉t♦r❡s✳
❊♠ ✷✵✵✽✱ ●✐♦✈❛♥② ❋✐❣✉❡✐r❡❞♦ ❬✶✾❪ ✉t✐❧✐③♦✉ ❡st❡ ♠❡s♠♦ ♠ét♦❞♦ ♣❛r❛ ❡q✉❛çõ❡s ❡❧í♣t✐❝❛s q✉❛s✐❧✐♥❡❛r❡s ❡ ♠♦str♦✉ ❛ ❡①✐stê♥❝✐❛ ❞❡ ✉♠❛ s♦❧✉çã♦ ♣❛r❛ ♦ s❡❣✉✐♥t❡ ♣r♦❜❧❡♠❛
(
−∆pu+|u|p−2u=f(u,|∇u|p−2∇u),
u∈W1,p(RN), u(x)>0, ♣❛r❛ t♦❞♦ x∈RN,
♦♥❞❡ 1 < p < N ❡ f : R× RN −→ R é ✉♠❛ ❢✉♥çã♦ ❝♦♥tí♥✉❛ q✉❡ ✈❡r✐✜❝❛ ❝♦♥❞✐çõ❡s ❛♥á❧♦❣❛s ❛ (f1), (f3)−(f5) ❡ s❛t✐s❢❛③✿
■♥tr♦❞✉çã♦ ✶✷
• ❡①✐st❡ q∈(p, p∗) t❛❧ q✉❡ lim |s|→+∞
|f(s,|ξ|p−2ξ)|
|s|q−1 = 0 ♣❛r❛ t♦❞♦ξ ∈R
N❀
• s7−→ f(s,|ξ|
p−2ξ)
sp−1 é ❝r❡s❝❡♥t❡ ♣❛r❛ ❝❛❞❛ s >0✱ ♣❛r❛ t♦❞♦ ξ∈R
N✳
❊♠ ✷✵✶✵✱ ❡st❡ ♠❡s♠♦ ♠ét♦❞♦ ❢♦✐ ❛♣❧✐❝❛❞♦ ♣♦r ❚❡♥❣ ❡ ❩❤❛♥❣ ❬✹✻❪ ♣❛r❛ ✐♥✈❡st✐❣❛r ❛ ❡①✐stê♥❝✐❛ ❞❡ s♦❧✉çõ❡s ♣❛r❛ ✉♠ ♣r♦❜❧❡♠❛ ❡♥✈♦❧✈❡♥❞♦ ❡q✉❛çõ❡s ❞✐❢❡r❡♥❝✐❛✐s ✐♠♣✉❧s✐✈❛s✳ ❊♠ ✷✵✶✷✱ ▲✐✉✱ ❙❤✐ ❡ ❲❡✐ ❬✸✶❪ ♠♦str❛r❛♠✱ ♠❡❞✐❛♥t❡ ❛ t❡♦r✐❛ ❞❡ ▼♦rs❡ ❡ ✉♠❛ té❝♥✐❝❛ ✐t❡r❛t✐✈❛✱ q✉❡ ♦ ♣r♦❜❧❡♠❛ (5) ♣♦ss✉✐ ♣❡❧♦ ♠❡♥♦s ✉♠❛ s♦❧✉çã♦ s♦❜ ❛ s✉♣♦s✐çã♦ ❞❡ q✉❡ f
t❡♠ ✉♠ ❝r❡s❝✐♠❡♥t♦ ❛ss✐♥t♦t✐❝❛♠❡♥t❡ ❧✐♥❡❛r ♥♦ ③❡r♦ ❡ ♥♦ ✐♥✜♥✐t♦ ❝♦♠ r❡❧❛çã♦ à s❡❣✉♥❞❛ ✈❛r✐á✈❡❧✳
◆♦ ❈❛♣ít✉❧♦ ✹ ❞❡st❡ tr❛❜❛❧❤♦ ❡♥❝♦♥tr❛♠✲s❡ ❛ ✈❡r✐✜❝❛çã♦ ❞❡ ❛❧❣✉♠❛s ❞❛s ❛✜r♠❛çõ❡s ❢❡✐t❛s ♥♦s ❈❛♣ít✉❧♦s ✷ ❡ ✸ ❡ ❛s ❞❡♠♦♥str❛çõ❡s ❞❡ ❛❧❣✉♥s r❡s✉❧t❛❞♦s té❝♥✐❝♦s✳
❈❛♣ít✉❧♦
1
◆♦çõ❡s ♣r❡❧✐♠✐♥❛r❡s ❡ r❡s✉❧t❛❞♦s
❛✉①✐❧✐❛r❡s
◆❡st❡ ❝❛♣ít✉❧♦ ❡♥✉♥❝✐❛♠♦s ❛s ♣r✐♥❝✐♣❛✐s ❞❡✜♥✐çõ❡s ❡ t❡♦r❡♠❛s ✉t✐❧✐③❛❞♦s ♥♦ ❞❡❝♦rr❡r ❞❡st❡ tr❛❜❛❧❤♦✳
❉❡✜♥✐çã♦ ✶✳✶✳ ❬✶❪ ❙❡❥❛♠ 1≤p≤ ∞ ❡ k ∈N✳ ❖ ❡s♣❛ç♦ Wk,p
0 (Ω) é ❞❡✜♥✐❞♦ ❝♦♠♦ s❡♥❞♦
♦ ❢❡❝❤♦ ❞❡ C∞
0 (Ω) ♥❛ ♥♦r♠❛k · kWk,p✱ ✐st♦ é✱
W0k,p(Ω) =C∞
0 (Ω)
k·kW k,p
.
❖❜s❡r✈❛çã♦ ✶✳✷✳ ❖ ❡s♣❛ç♦ W01,2(Ω) s❡rá ❞❡♥♦t❛❞♦ ♣♦r H1
0(Ω) ❡ s✉❛ ♥♦r♠❛ ❞❛❞❛ ♣♦r
kuk:=kukW1,2 0 =
Z
Ω
|∇u|2dx
1 2
, ♣❛r❛ t♦❞♦u∈W01,2(Ω).
❉❡✜♥✐çã♦ ✶✳✸✳ ❬✹✽❪ ❙❡❥❛X ✉♠ ❡s♣❛ç♦ ❞❡ ❇❛♥❛❝❤✳ ❯♠❛ ❛♣❧✐❝❛çã♦I :X −→Ré ❝❤❛♠❛❞❛
✉♠ ❢✉♥❝✐♦♥❛❧✳ ❆❝❡r❝❛ ❞❡ ✉♠ ❢✉♥❝✐♦♥❛❧ I :U −→ R✱ ♦♥❞❡ U é ✉♠ s✉❜❝♦♥❥✉♥t♦ ❛❜❡rt♦ ❞❡
X✱ ❞✐③❡♠♦s q✉❡✿
(i) t❡♠ ❞❡r✐✈❛❞❛ ❞❡ ●❛t❡❛✉① T ∈X∗ ❡♠ u∈U s❡✱ ♣❛r❛ t♦❞♦ h∈X✱
lim
t→0
1
t[I(u+th)−I(u)− hT, thi] = 0.
Pr❡❧✐♠✐♥❛r❡s ✶✹
(ii) t❡♠ ❞❡r✐✈❛❞❛ ❞❡ ❋ré❝❤❡t T ∈X∗ ❡♠ u∈U s❡
lim
t→0
1
khk[I(u+h)−I(u)− hT, hi] = 0;
(iii) ♣❡rt❡♥❝❡ ❛ C1(U,R) s❡ ❛ ❞❡r✐✈❛❞❛ ❞❡ ❋ré❝❤❡t ❞❡ I ❡①✐st❡ ❡ é ❝♦♥tí♥✉❛ ❡♠U❀
(iv) ✉♠ ♣♦♥t♦ ❝rít✐❝♦ u ❞❡ I é ✉♠ ♣♦♥t♦ ❡♠ q✉❡I′(u) = 0✱ ✐st♦ é✱
hI′(u), ϕi= 0, ♣❛r❛ t♦❞♦ ϕ∈X.
◆♦ ❈❛♣ít✉❧♦ ✸✱ sã♦ ✉t✐❧✐③❛❞♦s ♦ ❚❡♦r❡♠❛ ❞❡ ❈♦♥✈❡r❣ê♥❝✐❛ ❉♦♠✐♥❛❞❛ ❞❡ ▲❡❜❡s❣✉❡ ❡ ❛❧❣✉♠❛s ❞❡s✐❣✉❛❧❞❛❞❡s ❛✉①✐❧✐❛r❡s✱ q✉❡ s❡❣✉❡♠ ❡♥✉♥❝✐❛❞❛s ❛❜❛✐①♦✳
❚❡♦r❡♠❛ ✶✳✹✳ (❚❡♦r❡♠❛ ❞❛ ❈♦♥✈❡r❣ê♥❝✐❛ ❉♦♠✐♥❛❞❛ ❞❡ ▲❡❜❡s❣✉❡ )❬✹✼❪
❙❡❥❛ Ω⊂RN ✉♠ s✉❜❝♦♥❥✉♥t♦ ♠❡♥s✉rá✈❡❧✳ ❙✉♣♦♥❤❛ q✉❡ (fn) é ✉♠❛ s❡q✉ê♥❝✐❛ ❞❡ ❢✉♥çõ❡s
♠❡♥s✉rá✈❡✐s s♦❜r❡ Ωt❛✐s q✉❡ fn −→f✱ q✳t✳♣✳ ❡♠ Ω✱ q✉❛♥❞♦ n→ ∞✳ ❙❡ ❡①✐st❡ φ∈L1(Ω) t❛❧ q✉❡ |fn| ≤φ q✳t✳♣✳ ❡♠ Ω✱ ♣❛r❛ t♦❞♦ n✱ ❡♥tã♦
Z
Ω
fn −→
Z
Ω
f, q✉❛♥❞♦ n→ ∞.
❚❡♦r❡♠❛ ✶✳✺✳ ❬✽❪ ❙❡❥❛♠ (fn) ✉♠❛ s❡q✉ê♥❝✐❛ ❡♠ Lp(Ω) ❡ f ∈ Lp(Ω)✱ t❛✐s q✉❡
kfn−fkp −→0, q✉❛♥❞♦ n → ∞✳ ❊♥tã♦ ❡①✐st❡ ✉♠❛ s✉❜s❡q✉ê♥❝✐❛ (fnk) t❛❧ q✉❡
✶✳ fnk −→f q✳t✳♣✳ ❡♠ Ω✱ q✉❛♥❞♦ nk → ∞❀
✷✳ |fnk| ≤φ(x) q✳t✳♣✳ ❡♠ Ω✱ ♣❛r❛ t♦❞♦ k✱ ❝♦♠ φ ∈L
p(Ω)✳
❚❡♦r❡♠❛ ✶✳✻✳ ❬✶❪ ❙❡ 1≤p < ∞ ❡ a✱ b ≥0✱ ❡♥tã♦ (a+b)p ≤2p−1(ap +bp).
❚❡♦r❡♠❛ ✶✳✼✳ (❉❡s✐❣✉❛❧❞❛❞❡ ❞❡ ❨♦✉♥❣)❬✷✵❪ ❙❡❥❛♠ 1< p, q <∞, 1p + 1q = 1✳ ❊♥tã♦
ab≤ a
p
p + bq
q , ♣❛r❛ t♦❞♦s a, b >0.
❚❡♦r❡♠❛ ✶✳✽✳ (❉❡s✐❣✉❛❧❞❛❞❡ ❞❡ ❍ö❧❞❡r)❬✷✵❪ ❙✉♣♦♥❤❛ q✉❡ 1≤p, q ≤ ∞, 1p+1q = 1✳
❊♥tã♦✱ s❡ u∈Lp(Ω) ❡ v ∈Lq(Ω)✱ t❡♠♦s q✉❡
Z
Ω
Pr❡❧✐♠✐♥❛r❡s ✶✺
P❛r❛ ♦ ❞❡s❡♥✈♦❧✈✐♠❡♥t♦ ❞♦ ♣r♦❝❡ss♦ ❞✐❛❣♦♥❛❧ ❡ ♦ ❛r❣✉♠❡♥t♦ ❜♦♦tstr❛♣✱ ❢❡✐t♦s ♥♦s ❈❛♣ít✉❧♦s ✷ ❡ ✸✱ r❡s♣❡❝t✐✈❛♠❡♥t❡✱ ♥❡❝❡ss✐t❛♠♦s ❞❛s ✐♠❡rsõ❡s ❞❡ ❙♦❜♦❧❡✈ ❡ ❍ö❧❞❡r✳
❉❡✜♥✐çã♦ ✶✳✾✳ ❬✷✵❪ ❙❡❥❛♠ X ❡ Y ❡s♣❛ç♦s ❞❡ ❇❛♥❛❝❤ t❛✐s q✉❡ X ⊂ Y✳ ❉✐③❡♠♦s q✉❡ X
❡stá ✐♠❡rs♦ ❝♦♥t✐♥✉❛♠❡♥t❡ ❡♠ Y✱ ❡ ❡s❝r❡✈❡♠♦s X ֒→Y✱ ❞❡s❞❡ q✉❡
kxkY ≤CkxkX, ♣❛r❛ t♦❞♦ x∈X ❡ ♣❛r❛ ❛❧❣✉♠❛ ❝♦♥st❛♥t❡C > 0.
❉✐③❡♠♦s q✉❡ X ❡stá ✐♠❡rs♦ ❝♦♠♣❛❝t❛♠❡♥t❡ ❡♠ Y✱ ❡ ❡s❝r❡✈❡♠♦s Xcpct֒→Y✱ ❞❡s❞❡ q✉❡ X ֒→Y ❡ ❝❛❞❛ s❡q✉ê♥❝✐❛ ❧✐♠✐t❛❞❛ ❡♠ X é ♣r❡❝♦♠♣❛❝t❛ ❡♠ Y✳
❚❡♦r❡♠❛ ✶✳✶✵✳ (■♠❡rsã♦ ❞❡ ❍ö❧❞❡r )❬✶❪ ❙❡❥❛♠ k ∈N∪ {0} ❡ 0< ν < γ ≤1✱ ❡♥tã♦
✶✳ Ck,γ(Ω)cpct֒→Ck(Ω)❀ ✷✳ Ck,γ(Ω)cpct֒→Ck,ν(Ω)✳
❚❡♦r❡♠❛ ✶✳✶✶✳ (■♠❡rsã♦ ❞❡ ❙♦❜♦❧❡✈)❬✶✼❪ ❙❡❥❛♠ Ω ⊂ RN ✉♠ ❞♦♠í♥✐♦ ❧✐♠✐t❛❞♦
s❛t✐s❢❛③❡♥❞♦ ❛ ♣r♦♣r✐❡❞❛❞❡ ❞♦ ❝♦♥❡✱ m >0✱ j ≥0 ❡ 1≤p <∞✳ ❊♥tã♦✱
✶✳ ❙❡ m < N p✱
Wj+m,p(Ω) ֒→Wj,q(Ω), ♣❛r❛ t♦❞♦ p≤q ≤ N p
N −mp;
✷✳ ❙❡ m = N p✱
Wj+m,p(Ω)֒→Wj,q(Ω), ♣❛r❛ t♦❞♦ p≤q <∞;
✸✳ ❙❡ m > N
p > m−1 ❡ Ω t❡♠ ❛ ♣r♦♣r✐❡❞❛❞❡ ▲✐♣s❝❤✐t③ ❧♦❝❛❧✱
Wj+m,p(Ω)֒→Cj,λ(Ω), ♣❛r❛ 0< λ≤m− N
p.
❖❜s❡r✈❛çã♦ ✶✳✶✷✳ ❯♠ ❞♦♠í♥✐♦ Ω s❛t✐s❢❛③ ❛ ♣r♦♣r✐❡❞❛❞❡ ❞♦ ❝♦♥❡ s❡ ❡①✐st❡ ✉♠ ❝♦♥❡
❧✐♠✐t❛❞♦ K t❛❧ q✉❡ q✉❛❧q✉❡r x ∈ Ω é ♦ ✈ért✐❝❡ ❞❡ ✉♠ ❝♦♥❡ Kx ❝♦♥❣r✉❡♥t❡ ❛ K ❡ ✐♥t❡✐r❛♠❡♥t❡ ❝♦♥t✐❞♦ ❡♠ Ω✳
❚❡♦r❡♠❛ ✶✳✶✸✳ (■♠❡rsã♦ ❝♦♠♣❛❝t❛)❬✶✼❪ ❙❡❥❛♠ Ω ⊂ RN ✉♠ ❞♦♠í♥✐♦ ❧✐♠✐t❛❞♦
s❛t✐s❢❛③❡♥❞♦ ❛ ♣r♦♣r✐❡❞❛❞❡ ❞♦ ❝♦♥❡✱ m≥1✱ j ≥0 ❡ 1≤p < ∞✳ ❊♥tã♦
✶✳ ❙❡ m < N p✱
Pr❡❧✐♠✐♥❛r❡s ✶✻
✷✳ ❙❡ m = Np✱
Wj+m,p(Ω)cpct֒→Wj,q(Ω), ♣❛r❛ t♦❞♦ 1≤q <∞; ✸✳ ❙❡ m > Np > m−1 ❡ Ω t❡♠ ❛ ♣r♦♣r✐❡❞❛❞❡ ▲✐♣s❝❤✐t③ ❧♦❝❛❧✱
Wj+m,p(Ω)cpct֒→Cj,λ(Ω), ♣❛r❛ 0< λ < m− N
p.
◆❡st❡ tr❛❜❛❧❤♦✱ ❝♦♥s✐❞❡r❛♠♦s ♦ ♦♣❡r❛❞♦r ❞✐❢❡r❡♥❝✐❛❧ ♣❛r❝✐❛❧ ❧✐♥❡❛r ❞❡ s❡❣✉♥❞❛ ♦r❞❡♠
L✱ t❡♥❞♦ ✉♠❛ ❞❛s s❡❣✉✐♥t❡s ❢♦r♠❛s✿
Lu=−
N
X
i,j=1
aij(x)u xixj+
N
X
i=1
bi(x)u
xi +c(x)u, ✭✶✳✶✮
Lu=
N
X
i,j=1
(ai,j(x)u xi +b
i(x)u) + N
X
i=1
ci(x)u
xi +d(x)u, ✭✶✳✷✮
♦♥❞❡ ♦s ❝♦❡✜❝✐❡♥t❡s aij, bi, c: Ω−→Rsã♦ ❢✉♥çõ❡s ❞❛❞❛s✳
❉❡✜♥✐çã♦ ✶✳✶✹✳ ❬✷✹❪ ❖ ♦♣❡r❛❞♦rL s❡rá ❞✐t♦ ♥❛ ❢♦r♠❛ ♥ã♦ ❞✐✈❡r❣❡♥t❡ s❡ é ❞❛❞♦ ♣♦r(1.1)
❡ ♥❛ ❢♦r♠❛ ❞✐✈❡r❣❡♥t❡ s❡ é ❞❛❞♦ ♣♦r (1.2)✳
❖❜s❡r✈❛çã♦ ✶✳✶✺✳ ❙❡ ♥ã♦ ❢♦r ✐♥❞✐❝❛❞♦ ♦ ❝♦♥trár✐♦✱ L ❡st❛rá ♥❛ ❢♦r♠❛ ♥ã♦ ❞✐✈❡r❣❡♥t❡✳
❉❡✜♥✐çã♦ ✶✳✶✻✳ ❬✷✹❪ ❉✐③❡♠♦s q✉❡ ♦ ♦♣❡r❛❞♦r L é ❡❧í♣t✐❝♦ ♥♦ ♣♦♥t♦ x ∈ Ω s❡ ❛ ❢♦r♠❛
q✉❛❞rát✐❝❛ ❛ss♦❝✐❛❞❛ à ♠❛tr✐③ A(x) = [(aij(x))]é ♣♦s✐t✐✈❛ ❞❡✜♥✐❞❛✱ ✐st♦ é✱ s❡ λ(x) ❞❡♥♦t❛ ♦ ♠❡♥♦r ❛✉t♦✈❛❧♦r ❞❡ A✱ ❡♥tã♦
n
X
ij=1
aij(x)ξ
iξj ≥λ(x)|ξ|2 >0,
♣❛r❛ t♦❞♦ ξ = (ξ1, . . . , ξn) ∈ RN\{0}✳ ❖ ♦♣❡r❛❞♦r L é ❡❧í♣t✐❝♦ ❡♠ Ω s❡ ❢♦r ❡❧í♣t✐❝♦ ❡♠ ❝❛❞❛ ♣♦♥t♦ ❞❡ Ω✳ ❋✐♥❛❧♠❡♥t❡✱ ❞✐③❡♠♦s q✉❡ L é ✉♥✐❢♦r♠❡♠❡♥t❡ ❡❧í♣t✐❝♦ ❡♠ Ω s❡ ❡①✐st❡
θ0 >0 t❛❧ q✉❡ λ(x)≥θ0 ♣❛r❛ t♦❞♦ x∈Ω✳
❆❣♦r❛✱ ♣♦❞❡♠♦s ❛♣r❡s❡♥t❛r ❛❧❣✉♥s t❡♦r❡♠❛s ❝❧áss✐❝♦s q✉❡ ♥♦s ❛✉①✐❧✐❛rã♦ ♥❛ ♦❜t❡♥çã♦ ❞♦s r❡s✉❧t❛❞♦s ♣r✐♥❝✐♣❛✐s ❞❡st❡ tr❛❜❛❧❤♦✳
▲❡♠❛ ✶✳✶✼✳ (▲❡♠❛ ❞❡ ❍♦♣❢)❬✷✹❪ ❙✉♣♦♥❤❛ q✉❡ B ⊂ RN é ✉♠❛ ❜♦❧❛ ❛❜❡rt❛✱ L é ✉♠
♦♣❡r❛❞♦r ✉♥✐❢♦r♠❡♠❡♥t❡ ❡❧í♣t✐❝♦ ❡♠ B✱ u ∈C2(B) ❡ Lu ≥0 ❡♠ B ✳ ❙✉♣♦♥❤❛ ❛✐♥❞❛ q✉❡
Pr❡❧✐♠✐♥❛r❡s ✶✼
(i) s❡ c= 0 ❡♠ B ❡ ❡①✐st❡ ❛ ❞❡r✐✈❛❞❛ ♥♦r♠❛❧ ∂u∂η(x0)✱ ❡♥tã♦ ∂u∂η(x0)>0✳
(ii) s❡ c≤0 ❡♠ B ❡ u(x0)≥0 ❡♥tã♦ ✈❛❧❡ ♦ ♠❡s♠♦ r❡s✉❧t❛❞♦ ❞♦ ✐t❡♠ ❛❝✐♠❛✳
❚❡♦r❡♠❛ ✶✳✶✽✳ ❬✷✹❪ ❙✉♣♦♥❤❛ q✉❡ u ∈ C2(Ω), f ∈ C0,α(Ω) s❛t✐s❢❛③❡♠ ∆u =f ❡♠ Ω✳ ❊♥tã♦ u∈C2,α(Ω)✳
❚❡♦r❡♠❛ ✶✳✶✾✳ (❆❣♠♦♥✱ ❉♦✉❣❧✐s✱ ◆✐r❡♥❜❡r❣)❬✻❪ ❙✉♣♦♥❤❛ q✉❡ Ω⊂RN é ✉♠ ❞♦♠í♥✐♦
❞❡ ❝❧❛ss❡ C2 ❝♦♠ ∂Ω ❧✐♠✐t❛❞❛✱ f ∈Lp(Ω), 1< p <∞ ❡ u∈H1
0(Ω) é s♦❧✉çã♦ ❢r❛❝❛ ❞❡
(
−∆u=f ❡♠ Ω, u= 0 ❡♠ ∂Ω.
❊♥tã♦ u∈W2,p(Ω) ❡ ❡①✐st❡ ✉♠❛ ❝♦♥st❛♥t❡ C =C(Ω, p)>0 t❛❧ q✉❡
kukW2,p(Ω) ≤CkfkLp(Ω).
❚❡♦r❡♠❛ ✶✳✷✵✳ (❙❝❤❛✉❞❡r)❬✶✼❪ ❙✉♣♦♥❤❛ q✉❡ Ω⊂RN é ✉♠ ❞♦♠í♥✐♦ ❧✐♠✐t❛❞♦ ❞❡ ❝❧❛ss❡
C2,γ✱ f ∈C0,γ(Ω)✱ 0< γ <1 ❡ u∈H1
0(Ω)∩C0,γ(Ω) é s♦❧✉çã♦ ❢r❛❝❛ ❞❡
(
−∆u=f ❡♠ Ω, u= 0 ❡♠ ∂Ω.
❊♥tã♦ u∈C2,γ(Ω) ❡ ❡①✐st❡ ✉♠❛ ❝♦♥st❛♥t❡ C =C(Ω, γ)>0 t❛❧ q✉❡
kukC2,γ(Ω) ≤CkfkC0,γ(Ω).
❚❡♦r❡♠❛ ✶✳✷✶✳ (❊st✐♠❛t✐✈❛ ✐♥t❡r✐♦r ❞❡ ❙❝❤❛✉❞❡r)❬✶✼❪ ❙❡❥❛ L ✉♠ ♦♣❡r❛❞♦r
✉♥✐❢♦r♠❡♠❡♥t❡ ❡❧í♣t✐❝♦ ❝♦♠
max{kaijkC0,γ(Ω), kbikC0,γ(Ω), kckC0,γ(Ω) :i, j = 1, . . . , n} ≤α.
❊♥tã♦ ♣❛r❛ Ω0, Ω1✱ ❝♦♠ Ω0 ⊂⊂Ω1✱ ❡①✐st❡ ✉♠❛ ❝♦♥st❛♥t❡ C =C(N, γ, θ0, α)>0 t❛❧ q✉❡
kukC2,γ(Ω
0) ≤C{kLukC0,γ(Ω1)+kukC(Ω1)}, ♣❛r❛ t♦❞♦ u∈C
2,γ(Ω).
▲❡♠❛ ✶✳✷✷✳ (❊st✐♠❛t✐✈❛ ✐♥t❡r✐♦r Lp)❬✶❪ ❙❡❥❛♠ Ω
0, Ω ❞♦♠í♥✐♦s ❧✐♠✐t❛❞♦s ❞❡RN ❝♦♠
Ω0 ⊂ Ω✳ ❙✉♣♦♥❤❛ q✉❡ L é ✉♠ ♦♣❡r❛❞♦r ❞✐❢❡r❡♥❝✐❛❧ ♣❛r❝✐❛❧ ❧✐♥❡❛r ❞❡ s❡❣✉♥❞❛ ♦r❞❡♠
Pr❡❧✐♠✐♥❛r❡s ✶✽
❝♦♥st❛♥t❡ K t❛❧ q✉❡
kwkW2,q(Ω
0) ≤K(kLwkLq(Ω)+kwkLq(Ω)),
♣❛r❛ t♦❞♦ w∈W2,q(Ω)✳
❖ t❡♦r❡♠❛ ❡♥✉♥❝✐❛❞♦ ❛ s❡❣✉✐r ❡♥❝♦♥tr❛✲s❡ ❡♠ ●✐❧❜❛r❣ ❡ ❚r✉❞✐♥❣❡r ❬✷✹❪ ✭❚❡♦r❡♠❛ ✽✳✶✾✮ ❡ s❡rá ✉t✐❧✐③❛❞♦ ♣❛r❛ ❞❡♠♦♥str❛r q✉❡ ❛ s♦❧✉çã♦ ♦❜t✐❞❛ ♥♦ ❚❡♦r❡♠❛ ✵✳✷ é ❡str✐t❛♠❡♥t❡ ♣♦s✐t✐✈❛ ✭♦✉ ❡str✐t❛♠❡♥t❡ ♥❡❣❛t✐✈❛✮✳
❚❡♦r❡♠❛ ✶✳✷✸✳ ❬✷✹❪ ❙❡❥❛ L ✉♠ ♦♣❡r❛❞♦r ❞✐❢❡r❡♥❝✐❛❧ ♥❛ ❢♦r♠❛ ❞✐✈❡r❣❡♥t❡ s❛t✐s❢❛③❡♥❞♦✿
✶✳ ❊①✐st❡♠ ❝♦♥st❛♥t❡s Λ ❡ ν t❛✐s q✉❡
N
X
i,j=1
|aij(x)|2 ≤Λ2, λ−2
N
X
i=1
(|bi(x)|2+|ci(x)|2) +λ−1|d(x)|2 ≤ν2,
✷✳ Z
(d(x)v(x)−biv
xi) dx≤0, ♣❛r❛ t♦❞♦ v ≥0, v ∈C
1 0(Ω),
❡ u ∈ W1,2(Ω) s❛t✐s❢❛③❡♥❞♦ Lu ≥ 0 ❡♠ Ω✳ ❊♥tã♦✱ s❡ ♣❛r❛ ❛❧❣✉♠❛ ❜♦❧❛ B ⊂⊂ Ω t❡♠♦s
q✉❡ sup
B
u(x) = sup
Ω
u(x)≥0✱ ❛ ❢✉♥çã♦ u é ❝♦♥st❛♥t❡ ❡♠ Ω✳
◆♦ss♦ ♣ró①✐♠♦ ♦❜❥❡t✐✈♦ é ❡♥✉♥❝✐❛r ♦ ❚❡♦r❡♠❛ ❞❛ ❡st✐♠❛t✐✈❛ ✐♥t❡r✐♦r ❣r❛❞✐❡♥t❡ ❞❡ ▲❛❞②③❡♥s❦❛②❛ ❡ ❯r❛❧✬ts❡✈❛ ❬✸✹❪ q✉❡ ♥♦s ♣❡r♠✐t❡ ♦❜t❡r✱ ♥♦ ❈❛♣ít✉❧♦ ✷ ❞❡st❡ t❡①t♦✱ ✉♠❛ ❝♦t❛ s✉♣❡r✐♦r ✐♥❞❡♣❡♥❞❡♥t❡ ❞❡n♣❛r❛ ❛ s❡q✉ê♥❝✐❛ (|∇un|)✱ ♦♥❞❡ ❝❛❞❛un é s♦❧✉çã♦ ❞♦ ♣r♦❜❧❡♠❛
(2) s♦❜r❡Bn✱ n≥1✳ P❛r❛ ✐st♦✱ ❝♦♥s✐❞❡r❡ ❛ s❡❣✉✐♥t❡ ❡q✉❛çã♦ ♥❛ ❢♦r♠❛ ❞✐✈❡r❣❡♥t❡✿
d dxi
ai(x, u,∇u) +a(x, u,∇u) = 0, ✭✶✳✸✮ ♦♥❞❡ a(x, s, p) = a(x1, . . . , xN, s, p1, . . . , pN) ❡ ai(x, s, p) = ai(x1, . . . , xN, s, p1, . . . , pN)✱
i= 1, . . . , N✱ sã♦ ❢✉♥çõ❡s ❞❛❞❛s✳
❉❡✜♥✐çã♦ ✶✳✷✹✳ ❬✸✹❪ ❯♠❛ ❢✉♥çã♦u∈Wm,p(Ω) é ❝❤❛♠❛❞❛ s♦❧✉çã♦ ❧✐♠✐t❛❞❛ ❣❡♥❡r❛❧✐③❛❞❛ ❞❛ ❡q✉❛çã♦ (1.3)✱ ❞❡s❞❡ q✉❡ max
Ω
|u|<∞ ❡
Z
Ω
[ai(x, u,∇u)ηxi −a(x, u,∇u)η] dx= 0,
Pr❡❧✐♠✐♥❛r❡s ✶✾
❚❡♦r❡♠❛ ✶✳✷✺✳ (❊st✐♠❛t✐✈❛ ✐♥t❡r✐♦r ❣r❛❞✐❡♥t❡ ❞❡ ▲❛❞②③❡♥s❦❛②❛ ❡ ❯r❛❧✬ts❡✈❛)
❬✸✹❪ ❈♦♥s✐❞❡r❡ (1.3)✱ ♦♥❞❡ ❛s ❢✉♥çõ❡s a(x, u,∇u) ❡ ai(x, u,∇u), i = 1, . . . , N sã♦ ♠❡♥s✉rá✈❡✐s ♣❛r❛ x ∈Ω, u ❡ p ❛r❜✐trár✐♦s✱ ❡ ai(x, u,∇u) sã♦ ❞✐❢❡r❡♥❝✐á✈❡✐s ❝♦♠ r❡s♣❡✐t♦ ❛ x, u, p✳ ❆❧é♠ ❞✐ss♦✱ s❛t✐s❢❛③❡♠
✶✳ υ(|u|)(1 +|p|)m−2|ξ|2 ≤ ∂ai(x, u, p)
∂pj
ξiξj ≤µ(|u|)(1 +|p|)m−2|ξ|2✱ ♣❛r❛ ξ∈R N
✳
✷✳ N
X
i=1
|∂ai
∂u|+|ai|
(1 +|p|) +
N
X
i,j+1
∂x∂aij
≤µ(|u|)(1 +|p|)m✱
♦♥❞❡ m ≥ 1 ❡ υ, µ sã♦ ❢✉♥çõ❡s ❝♦♥tí♥✉❛s ❞❡✜♥✐❞❛s ♣❛r❛ t ≥ 0 t❛✐s q✉❡ υ é ♣♦s✐t✐✈❛ ♥ã♦
❝r❡s❝❡♥t❡ ❡ µ ♥ã♦ ❞❡❝r❡s❝❡♥t❡✳ ❙❡❥❛♠ u ✉♠❛ s♦❧✉çã♦ ❣❡♥❡r❛❧✐③❛❞❛ ❧✐♠✐t❛❞❛ ❞❛ ❡q✉❛çã♦
(1.3) ❡♠ W1,2(Ω) ❡ Ω
0 ⊂⊂Ω t❛✐s q✉❡
✸✳ Z
Ω0
(1 +|∇u|)m−2
N
X
i,j=1
u2xixj dx <∞✱
✹✳ Z
Ω0
|∇u|m+2dx <∞✳
❊♥tã♦✱ ♦ max
Ω0
|∇u| é ❧✐♠✐t❛❞♦ ♣♦r ✉♠❛ ❡①♣r❡ssã♦ ❡♠ t❡r♠♦s ❞❡ max
Ω |u|✱ m✱ υ(maxΩ |u|)✱
µ(max
Ω |u|) ❡ ❛ ❞✐stâ♥❝✐❛ ❞❡ Ω0 ❛ ∂Ω✳
❊♥✉♥❝✐❛r❡♠♦s✱ ❛❣♦r❛✱ ❛❧❣✉♥s r❡s✉❧t❛❞♦s ♣❛r❛ ♦ ♣r♦❜❧❡♠❛ ❞❡ ❛✉t♦✈❛❧♦r ❞♦ ❧❛♣❧❛❝✐❛♥♦ ❝♦♠ ❝♦♥❞✐çã♦ ❞❡ ❢r♦♥t❡✐r❛ ❞❡ ❉✐r✐❝❤❧❡t✳
❚❡♦r❡♠❛ ✶✳✷✻✳ ❬✷✵❪ ❙❡❥❛♠ Ω⊂RN ❝♦♠ ❢r♦♥t❡✐r❛ ❞❡ ❝❧❛ss❡ C∞ ❡ λ∈R✳ ❙❡ ϕ∈H1 0(Ω)
é ✉♠❛ s♦❧✉çã♦ ❢r❛❝❛ ❞❡ (
−∆ϕ =λϕ ❡♠ Ω,
ϕ= 0 ❡♠ ∂Ω, ✭✶✳✹✮
❡♥tã♦ ϕ ∈C∞(Ω)✳
❚❡♦r❡♠❛ ✶✳✷✼✳ ❬✷✵❪✳
(i) ❖ ♣r♦❜❧❡♠❛ (1.4) ♣♦ss✉✐ ✉♠❛ s❡q✉ê♥❝✐❛ ❞❡ ❛✉t♦✈❛❧♦r❡s
0< λ1 < λ2 ≤λ3· · ·, t❛❧ q✉❡ λk −→ ∞ q✉❛♥❞♦ k→ ∞. ❆❧é♠ ❞✐ss♦✱ λ1 = inf
v6=0
v∈H1 0(Ω)
kvk2
kvk2 2
Pr❡❧✐♠✐♥❛r❡s ✷✵
(ii) ❙❡ϕ1 é ✉♠❛ ❛✉t♦❢✉♥çã♦ ❛ss♦❝✐❛❞❛ ❛♦ ♣r✐♠❡✐r♦ ❛✉t♦✈❛❧♦rλ1❞♦ ♣r♦❜❧❡♠❛(1.4)✱ ❡♥tã♦
ϕ1 >0 ❡♠ Ω✳
❆♣r❡s❡♥t❛♠♦s✱ ❛❣♦r❛✱ ❛❧❣✉♥s r❡s✉❧t❛❞♦s s♦❜r❡ ❢✉♥❝✐♦♥❛✐s ❧✐♥❡❛r❡s ❡ ♦ ❚❡♦r❡♠❛ ❞♦ P❛ss♦ ❞❛ ▼♦♥t❛♥❤❛✱ ❞❡✈✐❞♦ ❛ ❆♠❜r♦s❡tt✐✲❘❛❜✐♥♦✇✐t③ ❬✼❪✱ q✉❡ é ❛ ❢❡rr❛♠❡♥t❛ ❡ss❡♥❝✐❛❧ ❞♦ ❈❛♣ít✉❧♦ ✸ ❞❡st❡ tr❛❜❛❧❤♦✳
Pr♦♣♦s✐çã♦ ✶✳✷✽✳ ❬✹✽❪ ❙❡I t❡♠ ❞❡r✐✈❛❞❛ ❞❡ ●❛t❡❛✉① ❝♦♥tí♥✉❛ ❡♠U✱ ❡♥tã♦I ∈C1(U,R)✳
❉❡✜♥✐çã♦ ✶✳✷✾✳ ❬✼❪ ❙❡❥❛ X ✉♠ ❡s♣❛ç♦ ❞❡ ❇❛♥❛❝❤✳ ❉✐③❡♠♦s q✉❡ I ∈C1(X,R) s❛t✐s❢❛③ ❛
❝♦♥❞✐çã♦ ❞❡ P❛❧❛✐s✲❙♠❛❧❡ ♥♦ ♥í✈❡❧ c((P S)c)✱ s❡ t♦❞❛ s❡q✉ê♥❝✐❛ (un)⊂X s❛t✐s❢❛③❡♥❞♦
lim
n→∞I(un) =c ❡ nlim→∞kI
′
(un)kX∗ = 0 ♣♦ss✉✐ ✉♠❛ s✉❜s❡q✉ê♥❝✐❛ ❝♦♥✈❡r❣❡♥t❡✳
❚❡♦r❡♠❛ ✶✳✸✵✳ (❚❡♦r❡♠❛ ❞♦ P❛ss♦ ❞❛ ▼♦♥t❛♥❤❛)❬✼❪ ❙❡❥❛ X ✉♠ ❡s♣❛ç♦ ❞❡ ❇❛♥❛❝❤
❡ I ∈C1(X,R) t❛❧ q✉❡ I(0) = 0 ❡
(I1) ❡①✐st❡♠ ρ✱ α >0 t❛✐s q✉❡ I(v)≥α✱ ♣❛r❛ t♦❞♦ v ∈∂Bρ(0);
(I2) ❡①✐st❡ ❡∈X t❛❧ q✉❡ k❡kX > ρ ❡ I(❡)≤0✳ ❙✉♣♦♥❤❛ q✉❡ I s❛t✐s❢❛ç❛ (P S)c✱ ❝♦♠
c:= inf
γ∈Γtmax∈[0,1]I(γ(t)),
♦♥❞❡ Γ :={γ ∈C([0,1], X) :γ(0) = 0 ❡ γ(1) =❡}✳ ❊♥tã♦ ❡①✐st❡ u6= 0 t❛❧ q✉❡ I(u) = c
❡ I′(u) = 0✳
Pr♦♣♦s✐çã♦ ✶✳✸✶✳ ❬✽❪ ❙❡❥❛ X ✉♠ ❡s♣❛ç♦ ❞❡ ❇❛♥❛❝❤✳ ❙❡ xn ⇀ x ❢r❛❝❛♠❡♥t❡ ❡♠ X ❡ s❡
In−→I ❢♦rt❡♠❡♥t❡ ❡♠X∗✱ q✉❛♥❞♦ n→ ∞✱ ❡♥tã♦ hIn, xni −→ hI, xi✱ q✉❛♥❞♦ n → ∞✳ ❋✐♥❛❧♠❡♥t❡✱ t❡r♠✐♥❛♠♦s ❡st❡ ❝❛♣ít✉❧♦ ❡♥✉♥❝✐❛♥❞♦ ❛❧❣✉♠❛s ❞❡✜♥✐çõ❡s ❡ r❡s✉❧t❛❞♦s té❝♥✐❝♦s ♥❡❝❡ssár✐♦s ♣❛r❛ ♦ ❈❛♣ít✉❧♦ ✷ ❞❡st❡ tr❛❜❛❧❤♦✳
▲❡♠❛ ✶✳✸✷✳ (❊①✐st❡♥❝❡✱ ●♦♥ç❛❧✈❡s ❡ ❙❛♥t♦s)❬✷✽❪ ❙❡❥❛ Ω⊂RN ✉♠ ❞♦♠í♥✐♦ ❧✐♠✐t❛❞♦
❝♦♠ ❢r♦♥t❡✐r❛ s✉❛✈❡✳ ❙✉♣♦♥❤❛ q✉❡ b ∈ C0,α(Ω) ❝♦♠ b(x) > 0✱ ♣❛r❛ t♦❞♦ x ∈ Ω✱ ❡
g ∈C1((0,∞),(0,∞))s❛t✐s❢❛③
✶✳ lim
s→0+ g(s)
s =∞ ❡ slim→∞
g(s)