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(1)Cyclical versus Non-Cyclical Harvesting Policies in Renewable Resource Management Katrin Erdlenbruch, Alain Jean-Marie, Michel Moreaux, Mabel Tidball. To cite this version: Katrin Erdlenbruch, Alain Jean-Marie, Michel Moreaux, Mabel Tidball. Cyclical versus Non-Cyclical Harvesting Policies in Renewable Resource Management. Monte Verità Conference on Sustainable Resource Use and Economic Dynamics - SURED 2008, Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich). Zürich, CHE. Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), CHE., Jun 2008, Monte Verita, Switzerland. 34 p. �hal-02821646�. HAL Id: hal-02821646 https://hal.inrae.fr/hal-02821646 Submitted on 6 Jun 2020. HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers.. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés..

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(108)  .  .   .       xsup   xns   0 < xns < xsup < +∞     F : (0, xsup ) → R  .     (0, xns )   

(109)    .  (xns , xsup )   F (0) = F (xns ) = 0  limx↓0 F (x) = F (0)     F              &  ) *     &    .    x0 ∈ (0, xsup )  &  xsup      

(110)           

(111) #         xns            

(112)

(113)    x0   0 < x0 < xsup .  

(114)  

(115)  !                                  (

(116)            @ := {(ti , Ii ), i = 1, 2, . . .}   &    

(117)   ti         Ii         &                  0 ≤ t1    ti ≤ ti+1   i = 1, 2, . . .   limi→+∞ ti = +∞ A           &       n ≥ 0   ti = +∞   i > n  &         . Ii ≥ 0   xi − Ii ≥ 0 , -. )7*.

(118)      . xi = lim x(t) , t↑ti.   x1 = x0

(119)   t1 = 0,. ),*.      

(120)     . x(t) ˙ = F (x(t))  ti < t < ti+1   x(ti ) = xi − Ii  i = 1, 2, . . . x(t) ˙ = F (x(t))  0 < t < t1   x(0) = x0.  t1 > 0.. )-* )9*.     xi    %     <    

(121)   ti    xi − Ii   % <        t1 = 0    x1    .             x0  '     

(122)          %   .   )7*B)9*        @     Fx0 .  

(123)   0    

(124)           

(125)    %         %        

(126)  !             

(127)       ti  Ii   xi        ti   π(xi , Ii )           

(128)     .   .     π(x, I)       D := {(x, I), x ∈ (0, xsup ) I ∈ [0, x]}     C 1        π ¯ < +∞     π(x, 0) = 0 ∀x ∈ (0, xsup )     πI (x, I) := (∂π/∂I)(x, I)       I ↓ 0   x ∈ (0, xsup ). @                    r           .                       .            

(129)          %

(130)                 )@* )@*. sup Π(@) :=.  ∈Fx0. ∞ . e−rti π(xi , Ii ) .. i=1.          Π         Fx0 .      . !                 

(131)  =    &    

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(133) 

(134)        

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(136)  .

(137)    . v(x) =. sup Π(). ∈Fx. )6*.  

(138)       

(139)        . v(x) =. sup y∈[0,xsup ) t≥0. 

(140)  . e−rt [π(φ(t, x), φ(t, x) − y) + v(y)] ,. φ(t, x)  

(141)      

(142)      

(143)    ) *  

(144) x(0) = x.             

(145) 

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(147)  7,6. D %E% + F. A  #1   +7.. . )8*. 4*.                

(148) .       

(149) . .   

(150)     %          )@*     

(151)   .                 )(@* !               !               )(@*   )@*. .       !   

(152)    .        .                  

(153)             :      τ (x, y)          

(154)    x  y  x ≤ y          0 < x ≤ y < xns   y 1 τ (x, y) = )3* du. x F (u) 2   (   F (xns ) = 0  

(155)  

(156) τ (x, y)  

(157)   y = xns     .  . limy↑xns τ (x, y) = +∞  0 < x < xns              xns G. 

(158)  . limy↑xns τ (x, y) < +∞  0 < x < xns            xns        

(159)           

(160)   x   

(161)   xns       x(t) = xns  t ≥ τ (x, xns )         x(t) ˙ = F (xns ) = 0.         (    F (0) = 0 (   &   x(0) = 0         ) *  x(t) = 0   t ≥ 0          τ (0, y) = +∞  y > 0   τ (0, 0) = 0

(162). )& % &    limx↓0 τ (x, y) = +∞  %+ & $   &  $ 6. 6.

(163)  

(164)   !   .          (                 %    x   x ¯G              < 

(165)   .                ¯ ! .          .

(166)      x        (             0 ≤ x < x ¯ ≤ xns  ! ¯G * .             *    

(167)    x   xG     2        .     x0 ≤ x ¯                    .     !       G(x, x ¯, x0 )                        .     x0     .       G     

(168)       x ¯   x. *  0 ≤ x < x ¯ < xns   t1 = τ (x0 , x ¯) ti = t1 + (i − 1)τ (x, x ¯)  i = 2... Ii = x¯ − x   i          . G(x, x¯, x0 ) := π(¯ x, x¯ − x). e−rτ (x0 ,¯x) . 1 − e−rτ (x,¯x). )4*. *  0 ≤ x < x ¯ = xns    2 D   t1 = +∞    G(x, xns , x0 ) := 0    D   t1 = τ (x0 , xns )   ti = t1 + (i − 1)τ (x, xns )  i = 2... Ii = xns − x   i . ¯ = xns           

(169)   )4*   x. *  x = 0        G             ¯))  F   τ (0, y) = +∞ 

(170)   exp(−rτ (x, x (         G      x < x ¯       .         x0 ≤ x ¯ !    

(171)  .     x = x ¯      x0  $    x = x¯      )4*           ¯→x=x (  7 H  (  7 G          x   x0 ≤ x  

(172) . G(x, x, x0 ) = πI (x, 0). F (x) −rτ (x0 ,x) e . r. ) F*.   

(173)    τ (x, y)   )3*      y ≤ x    )4*         G  x0 > x ¯   =                

(174)              

(175) . $ x¯ &&   %  1  & 1&  %&  &    & x¯ > xns &    1  &  %    &

(176) 1 &    + +   < 1 t = τ (x , x ) + d  1 0 ns ti = t1 + (i − 1)(τ (x, xns ) + d)  i = 2...  & d ≥ 0 >1%  & &+ &   && < &  &   d  π() > 0  π() < 0  & %  d 1  +∞C & & &  + % 1% 8.

(177) 

(178)  

(179)  ! /

(180)       G(x, x ¯, x0 )   0 ≤ x ≤ x¯ ≤ xns    0 ≤ x0 ≤ xns            )(@* )(@* :. max. x, x ¯; 0≤x≤¯ x≤xns. G(x, x¯, x0 )..  "

(181) 

(182)   # $  !    

(183)                π       &        <    @  )@* =       <      (   (, '     

(184)   .   ".     π    . π(a, a − c) + π(b, b − d) ≤ π(a, a − d) + π(b, b − c). ). *.   a ≥ b ≥ c ≥ d  

(185)    #     . #

(186) .  

(187) . π     

(188) . ! " g(x, y) = π(x, x − y)    xsup 

(189)     a, b, c, d 

(190) 

(191)  min(a, b) ≥. > x ≥ y ≥ 0

(192)  g     max(c, d). g(min(a, b), min(c, d)) + g(max(a, b), max(c, d)) ≤ g(min(a, b), max(c, d)) + g(min(a, b), max(c, d)) . ! . π

(193)  #     

(194)  ∂2π ∂2π + ≥ 0. ∂x∂I ∂x2. !    $

(195)      

(196)     

(197) . π(x, x − z) ≥ π(x, x − y) + π(y, y − z) .  . ) 7*. x ≥ y ≥ z. iv)  π(x, I) = R(I) 

(198)  R   % &    R   %  .

(199) . $

(200) % . ' .  ) 7* )     & *    &                  2     :  +6. D  1 iii) (  ,     (  ,   

(201)      <     .        F (·)       r  3.

(202) #

(203)   

(204). i<j. &        P 

(205) 

(206)  

(207) 

(208)  

(209)   %   xi ≥ xj ≥ xi − Ii ≥ xj − Ij 

(210) . i)   .

(211)   

(212)      ). i  j. * 

(213)  P    .

(214)   

(215)    ) *   P    

(216)  

(217)   %   

(218)        P   

(219)  

(220)  

(221)   (xi , Ii )  (xj , Ij )   P   

(222)    

(223)   (xk , Ik )  

(224) xk = xi − Ii  Ik = xj − xi + Ij . ii)   .       

(225)  (   (-.   %

(226)   &

(227) '     $  

(228) 

(229)           )@*   )(@*                        @  )(@*        x0      1 4  (   (9 (   &  ¯∗ )        )(@*     x0         (x∗ , x.   &.    )(@*    &         (x∗ , x ¯∗ )   ∗.    x < x ¯  ∗. H    -      

(230)   %    )@*    %  I   @ J               . * 

(231)

(232)         xG * 

(233)  x   y G * 

(234) ¯]      &           

(235)  [x, x & .  x   y  )@* :. max x,y;. e−rτ (x0 ,x) [π(x, x − y) + G(x∗ , x¯∗ , y)] .. 0≤y≤x≤xns x0 ≤x; y≤¯ x∗.  

(236)    %         )@*.  .  

(237)    '()

(238)  " (x∗ (x0 ), y ∗ (x0 ))   

(239)  %  *#      + !

(240)  

(241)      +! . v(x0 ) =. ⎧ ¯∗ , x0 ) ⎨ G(x∗ , x ⎩. e−rτ (x0 ,x. ∗ (x. 0 )). if x0 < x¯∗ [π(x∗ (x0 ), x∗ (x0 ) − y ∗(x0 )) + G(x∗ , x¯∗ , y ∗ (x0 ))] if xns ≥ x0 ≥ x¯∗ . ) ,*. ,   

(242)   %      +! 

(243) 

(244)        . t1 = τ (x0 , x¯∗ ), . ti = t1 +(i−1)τ (x∗ , x¯∗ ),. xi = x¯∗ ,. Ii = x¯∗ −x∗ ,. i = 1, 2, . . . ,. x0 < x¯∗   t1 = τ (x0 , x∗ (x0 )), x1 = x∗ (x0 ),. . i ≥ 1,. t2 = τ (y ∗ (x0 ), x¯∗ ),. I1 = x∗ (x0 ) − y ∗(x0 ),. ti = t2 + (i − 2)τ (x∗ , x¯∗ ), xi = x¯∗ ,. x0 ≥ x¯∗  4. Ii = x¯∗ − x∗ ,. i ≥ 2,. i = 2, . . . ,.

(245)       

(246)  (   (9                      

(247)  [x∗ , x ¯∗ ]                         x0 < x ¯∗               <          x0 ≥ x ¯∗      ∗      

(248)   

(249)    x (x0 )    y ∗(x0 )  <.   !       

(250)       )@*   )(@*         (   (6.  ". "   '(.

(251) 

(252) . i)    )

(253)      

(254)  +!

(255)     

(256) 

(257)   ii)  +!

(258)     

(259)  +!

(260)     

(261) 

(262)     

(263)   %         +!  

(264) 0 ≤ x < x ¯ ≤ xns  !                  )@*                 )(@*    !         

(265)     .                   . #

(266) "  +x, x¯!      

(267)  %       +!  

(268) 0 < x < x¯ < xns x0 < x¯ +    ! 

(269)  

(270)              e−rτ (x,¯x) ∂π r π(¯ x, x¯ − x) , = ∂I F (x) 1 − e−rτ (x,¯x). ) -*. r 1 ∂π ∂π + = π(¯ x, x¯ − x) . −rτ ∂x ∂I F (¯ x) 1 − e (x,¯x). ) 9*. e−rτ (x,¯x) ∂π F (x) = π(¯ x, x¯ − x) , ∂I r 1 − e−rτ (x,¯x). ) 6*. ∂π ∂π ∂π F (x) dπ = + = . dx ∂x ∂I ∂I F (¯ x)e−rτ (x,¯x). ) 8*. K

(271)

(272)   .    .            

(273) 

(274)   

(275)   

(276)     

(277)               .     &      

(278)         %            .       

(279) 

(280)           &   

(281) 

(282)   

(283) 

(284)     

(285)        

(286)                        

(287)      0    

(288)   

(289)      

(290)    

(291) 

(292)       . F.

(293) !.  " 

(294)  .          &    

(295)                      

(296) .   !        IL1AJ )L    *    

(297)       

(298)      &  x !                    %       &   

(299)        .  .  

(300)  

(301)      π(¯ x, I)         

(302)     

(303)   

(304)   F (x)  x → 0 

(305)   !  ! . F (x) ∼ αxβ  

(306) α > 0  β > 1 

(307)  

(308)  ."/   

(309)  F (x) = αx + O(x2 )   a = r/α 

(310) . '! . a > 1 

(311)  ."/

(312) . $!  a = 1        ."/  

(313)  

(314)   %   .  )9F*  

(315) . exp(−rτ (k, xm )) ≤ πI (xm , xm ) . k→0 k. π(xm , xm ) lim  !  ! . xm 

(316)   . ) 3*. a < 1 

(317)  ."/  

(318) . F (x) ∼ αxβ  

(319) α > 0  0 ≤ β < 1 

(320)  ."/  

(321) .             . 

(322)                 

(323)                 (   (8. #. (. $ %      &       & . ! ) *+! . !             

(324)                  ' +,. '         )(@*     x = x ¯    %     max G(x, x, x0 ), 0≤x≤xns.  G 

(325)   ) F*     .  . πIx (x, 0)F (x) + πI (x, 0)[F  (x) − r] = 0 .. ) 4*. 1      x∗     ) 4* !       .           

(326)            πI (x, 0)  .         )   ' +,.  '   0  +-.* .

(327)   L&  ) 4*       &               

(328) '#  

(329)         ∞ )'@* max e−rt πI (x(t), 0)h(t) dt , )7F* h(·). 0. x˙ = F (x) − h,. )7 *.  x0

(330)    0 ≤ h(t) ≤ hmax   t        .     '#            

(331)

(332)                 . ( , !! ).  -./ -.  - . !             

(333)   '>        ¯       @  )@* )(@*     x = x.  &.  

(334)     +!   

(335)        +!. x = x¯ = x∗  

(336)     % .  '.  

(337)     +!   

(338)    x = x ¯ = x∗  

(339)   %           

(340) x ¯ − x =   

(341)  

(342)   G(x∗ , x∗ , x0 ), ∀x0 ≤ x∗   

(343)   

(344)  

(345)   %    x 

(346) 

(347) . lim G(x , x + , x0 ) = G(x∗ , x∗ , x0 ). →0.       L  +4.       &  

(348)       

(349)    #       ) K   !  +7 .*. $

(350) % .        G(x∗ , x∗ , x0 )           )'@*    )7F*B)7 *  x0 ≤ x∗       )(@*    x < x ¯               .  (.  +!

(351)       +

(352)     

(353)     +!  

(354) 

(355) . x < x¯! 

(356)  

(357)      

(358)      v(x0 )    

(359)  

(360)        +&!   )7F*()7 * G(x∗ , x∗ , x0 )   x0 ≤ x∗ . '. $ %      &   (    & .          :    ;>  +8.      

(361)                                     +8.   . 7.

(362) 0 &

(363) '   1! ) '   +! . ( )  

(364)   

(365)

(366) 

(367)    .    :    ;               xt+1 = f (xt ) − ut = min[M, (1 + λ)xt ] − ut   xt , ut ≥ 0 ∀t ≥ 0   M = 1 !    

(368)        !  

(369)      x(t) ˙ = F (x(t)) 2. F (x) = Ax.  x < xns = 1.   F (x) = 1 − x.  x ≥ 1..             (    

(370) 

(371)     &           

(372)   

(373)    . x(t) = φ(t, x0 ) = min(x0 eAt , 1) .          :    ;>   #     .    Δ     xt+1 = φ(Δ, xt ).      &   f (xt ) = φ(Δ, xt )   xt        . (1 + λ)xt = xt eAΔ . !    

(374) 

(375)     A       :    ;>   1 + λ log(1 + λ) . A = )77* Δ 1             

(376)   x  y           x ≤ y ≤ 1  y  y 1 1 1 y τ (x, y) = du = du = log . A x x F (u) x Au. ( *  !       

(377)   g        :    ;>      

(378)  π(¯ x, I) = R(I). $          

(379)      ' .  ) *  &        R 

(380)  1 iv) 1 >     

(381)          v(t)       

(382)  v(t) = v0 e−rt .           . vt = δvt−1 = δ t v0 .. ,.

(383) 2         vt = v(Δt)   . δ t = e−rtΔ  . log δ = −rΔ .. !    :    ;>  a      . a = −. (". log δ rΔ r = = . log(1 + λ) AΔ A. 

(384)  +

(385)  !. !     .       G              )(@*       . • 

(386)       x < x¯     r. R(¯ x − x)( xx¯0 ) A R(¯ x − x)( xx¯0 )a G(x, x¯, x0 ) = = . r 1 − ( xx¯ )a 1 − ( xx¯ ) A. )7,*. ¯ = xns = 1   x = 0      

(387)  x •      K   π(¯ x, I) = R(I)  . ∂ π(¯ x, I) = R (0). I→0 ∂I lim. / . G(x, x, x0 ) = R (0). Ax  x0  Ar xa = R (0) 0 x1−a . r x a. )7-*. :    ;       

(388)        . R (x) . xR(x). ε(x) =. )79*. ! . #

(389) &.

(390)    

(391)   . 0 ≤ x ≤ x¯ ≤ 1. i)  a < 1 

(392)  0 < ε(¯ x − x) − 1 <. ∂G (x, x¯, x0 ) < ε(¯ x − x) − a . ∂ x¯. )76*. ii)  a > 1 

(393)  ε(¯ x − x) − a <. ∂G (x, x ¯, x0 ) < ε(¯ x − x) − 1 . ∂ x¯ -. )78*.

(394) iii)  a = 1 

(395)  ∂G 1 1 (x, x¯, x0 ) = (ε(¯ x − x) − 1) > 0 . G(x, x ¯, x0 ) ∂ x¯ x¯ − x. #

(396) '. . a > 1 

(397) . )73*. ∂G < 0. ∂x.                 ε > 1        R      R(0) = 0 (   &   1 -   9    

(398)   %   . #

(399) (.

(400)   . G    )7,*  )7-*

(401)  

(402)       . i)  a < 1 

(403)  

(404)   %     (x, x ¯)  

(405) 0 < x ≤ x¯ = 1    max G(x, x ¯; x0 ) .. 0≤x≤¯ x≤1. ii)  a > 1 

(406)    x¯. max G(x, x¯; x0 ) = 0.. ),F*. max G(x, x¯; x0 ) ∈ (0, 1) .. ), *.  . iii)  a = 1 

(407)   . )74*. 0≤x≤1. 0≤x≤¯ x≤1. 0 , ! )  , !

(408) !  )  . :    ;      a         .     

(409)     

(410)     A    .        

(411)               ( 

(412)     

(413)   ε 

(414)           

(415)     a                     

(416)     

(417)   ε    a         ) +8 1 9.*   #

(418)   a < 1 :    ;        .               @.  ii.3)   

(419)            F (x) = Ax   a = r/A   # 

(420)      

(421)        :    ;    @.   =               .  

(422)   ,    #

(423)   a > 1 :    ;             !       @.  ii.1)    1 9 ii) 0 1 - i)    @.  ,  74F  +8.. 9.

(424) ).        *  +

(425) . . '                                      

(426)                  '        .      )                *            

(427)                #               ' +,. !                       2            .                  !                      

(428)           

(429)

(430) . 2  "  1 %

(431)   !    3 

(432) . ' +,.     <                          h(t)          % x = x(t)       

(433)   E = E(t)   h = Q(E, x)      Q(E, x).         

(434)     '          ' #:

(435)       . Q(E, x) = aE α xβ ,  aα   β  .          α = 1     axβ          

(436)  "      S(x)   h h = Q(E, x) = S(x)E   E = S(x)                 c = CE                 . cc (x, h) = CE =. C h S(x).    a = 1   β = 1  . C h, x                cc (x, h) =. πc (x, h) = (p −. C ) h, x.  p     . 2  "  1 %

(437)      

(438)        

(439)           

(440) #   ' )< 

(441)                   *  

(442)     

(443)  . π(x, I) = a(x) d(I) . . D+ & &  1   &  & &  &   &   6.

(444) $                          

(445)                                                  &    

(446) &       .   ".  

(447)     +!  

(448)     

(449)       . ∗. (x ) x     +'0!  a(x∗ ) > 0  d (0) + d (0) aa(x ∗ ) > 0 

(450)  

(451)   %   ∗.      +!. .   "                     )(@* H

(452)   &           (  -     ,        )@*    ! π(x, I) = a(x)d(I) &  ) F* 

(453)  . G(x, x, x0 ) = a(x)d (0). F (x) rτ (x0 ,x) e . r.  &  ) 4*        .    . a (x)F (x) + a(x)(F  (x) − r) = 0.. ),7*. !   G  

(454)      x = x ¯ 

(455)    . G(x + h, x + k, x0 ) ∼ = G(x, x, x0 ) + . B(x, h, k) =. F (x) rτ (x0 ,x) B(x, h, k), e r.

(456)  r − F  (x) r − F  (x)     a(x) d (0) + d (0) + hd (0) a (x) − a(x) , 2 F (x) F (x).  = h−k..      h    > 0   B(x∗ , h, h − ) > 0          

(457)        ) x < x ¯*  

(458)     G(x∗ , x∗ , x0 ) ¯ D   x∗                  x = x   ),7*  "   .     .

(459) B(x∗ , h, k)

(460)    % . a(x∗ ) > 0  . d (0) + d (0). a (x∗ ) > 0. a(x∗ ). !                      

(461)   

(462)       . 2   !  !.   +7-.          

(463)                

(464)          F (x) = s0 x(1 − x/K) 

(465)      g(x, y) = a(x)d(x − y)  . a(x) = p −. bc , x 8. d(I) = I ..

(466) !          . K = 500,. s0 = 0.08,. p = 50,. b = 0.3,. r = 0.03,. c = 9375.00 .. !             . •       )(@*  a      

(467)  .  •           )@*  .            

(468)                

(469)   

(470)       '>  )         c(x) = b/x*    (  -      G    

(471)         x ¯∗ 268.32 x∗ 106.31. 0 100 200. y. 300 400.

(472) 1  x(t) = u  x(t0 ) = x0  xdt ˙ = du  x(t1 ) = x1  !    x1  x1 hmax hmax lim (p − c(u)) du = (p − c(u)) lim du hmax →∞ x hmax →∞ F (u) − hmax F (u) − hmax x0 0  x0 (p − c(u))du . = x1.                     x¯ π(¯ x, x¯ − x) = [p − c(x)] dx .. ),,*. x. $

(473) % ".  

(474)           . i)   a ≥ b > c ≥ d . a. π(a, a − c) + π(b, b − d) =. . d. [p − c(x)] dx +. d. [p − c(x)] dx. c. = π(a, a − d) + π(b, b − c) . ii) (  ,      &  ) *     πxI + πII = 0 . iii) (    1 8 ) (   (7*     y ∗ (x0 )          y ∗(x0 ) = x∗    ) 4* 1   .                   

(475)  . c(x) =. b xα+1. ,. F (x) = g0 x(K − x),. α≥0.. ),-*.         

(476)  .  ". 1 π(·) c(·)  %      +!. F (·)    +. !(+ )!. . x∗    +'0!    . ¯   H(x, x¯) := ! 

(477) 

(478)    ∀x < x ∗ x = x¯ = x  

(479)     '  . . H(x, x ¯) = −p + c(x) + [p(¯ x − x) −. x ¯. −rτ. c(u)du] e x. ∂G (x, x¯) ∂x. > 0  . e−rτ r . F (x)(1 − e−rτ ) 1 − e−rτ. ! τ = τ (x, x ¯)G 1     

(480)  H(x, x¯). H(x, x ¯) =. H2 (x, x¯) x (p − c(x))(K − x) + α x g0 (K − x) + H3 (x, x¯) H1 (x, x¯) 4.

(481) . . . x¯(K − x) − 1 < 0, x(K − x¯)   r x¯(K − x) g0 K < 0, H2 (x, x¯) = −α g0 x(K − x¯). H1 (x, x ¯) = α x g0 (K − x).  .  g rK 0. H3 (x, x ¯) = r p α(¯ x − x) + r b c (¯ x−α − x−α ).. ∂H3 (¯ x, x¯) = r α(−p + c(x))   x   −p + ∂x c(x) < 0   H3 (x, x¯) > 0 (  &.    H(x, x¯) > 0    

(482)   

(483)       

(484)          #    

(485)   

(486)        $   ' +,.             

(487)             D                 b  

(488)       '>      c(x) = xα+1       &    9 .     x0 < x∗    .     

(489)   x∗     

(490)   !   H3 (¯ x, x¯) = 0  . ,.   . !           

(491)      #    

(492)    

(493)                

(494)              

(495)          %    )@*                

(496) # 

(497)     

(498)    ?    ?        @  )@*   &           %           !          

(499)                            '#  0 K  ( @  !                         

(500)                        !                  

(501)            

(502)                                                         

(503)                              #      

(504)   

(505)     &     # 

(506)      '                           !      

(507)          

(508)                                          

(509)   

(510)       

(511)      '                             7F.

(512) /  

(513)       

(514)                       

(515)        .         .                  . 7.

(516) - .    + . (   K 1 ; 2  2  2     $ M 

(517)  )7FF-* =               :      $ (  N   (

(518)    L   36)7* 9, # 9-7 +7. A   ( N1 1   ) 437* ' O     5&   & #     05  0 5 &  >  & :  +,. ' '! ) 44F* 0   A     =  0 

(519)   K#   K N !    2  +-. ' '!   DK 0  ) 489*  L     

(520)   0 '   (    ( N   L     L     0 

(521) #  7 47# F6 +9. ' '! ' /   DK 0  ) 484*         #      @        L    -8 79#-8 +6. :  0/( ) 44,* 0 0   =  %   @  / +8. :  /   0 ; ) 448* =  L   =  L     K   K  '   '  L       '  K      N   L    86 787#748 +3. :  /   0 ; ) 444* =       

(522) 

(523)            L    , ,F4#,78 +4. L  ; )7FF9* L   5        P H #  5 0    87  + F. D %% K ) 484*G P  ,P  H  5  @  :  + . D   K Q 2  1;   2 2   )7FFF* /    0 # 

(524)   K   K  '  ' > $  '   (  N   (

(525)    L   37),* 98F#93F + 7. /   K ) 489*   :   ( $  (   '    ' #   N   L   3)7* 9 # 8, + ,. /   K   N L !  ) 448* ( 0  K

(526)   = ( K H N   L     L     0 

(527)  ,7 #7  + -. N&  : 1 ) 487* (   #    #   0   A    97, #797 + 9. N&  : 1 ) 48-* (   #    #         =   K 77 743#,F, + 6. 15  :   $ M 1

(528) ) 443* =  '     2   =  % . L   '  

(529)  H   @ ,9, . 77.

(530) + 8. 1   0;  @0   ( $ )7FF *  

(531)       

(532)  K   L 

(533)  L   7, 7- #793 + 3. 1 K   K 2  ) 488* $      =  L   K   K      L   K  3),* 9,9#997 + 4. 1 K   K 2  ) 484* $ #'     =  /

(534) 2  

(535)   K   K  '   N   L   7)-* 688# 64  +7F. K !N ) 43-* (          

(536)          0   A    77 , ,#,,8 +7 . K K N#A !  ) 443* M    (   2

(537)  8,,  +77. 2   (   ; 2  ) 438* =  '     L   (#     (  L  +7,. 2

(538)  K !

(539)  Q   0 : )7FF6*     

(540)     

(541)             <   N   L     L#     0 

(542)  97 937#944 +7-.    0 )7FF8* L                  .   L       K L   ,8 6-,#694 +79. %#0  N   0   )7FF7*          H    

(543)  L    :   H    R H; +76. M  ; ) 468* '  2    N  2   M   L    ,9 78,#788 +78. !   ) 449*  '  L    K   K 2  0 A =  N   L     L     0 

(544)  74 797#76 . 7,.

(545) /. /  ".  6

(546)   !! 5  1 %

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