ðj
mjÞ
2a 2a 2a 2a
where q0 ¼ max q1 ; 2 max q2 ; q3 ðk Þ 。 If the minimum of Dðj/m jÞ can be obtained and is larger than zero, (22) will
be satisfied。
It follows from j/m j ¼ jð a 1 — x ÞfðtÞj that j/mj 6 kð a 1 — x Þk2kfðtÞk2 based on the Ho€lder inequality, which implies
qffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi2ffi
that j/mj 6 a2 þ ð1 — xÞ kfðtÞk2。 From (21), one can see that the state of the system asymptotically converge to the origin,
which means that kfðtÞk2 6 kfð0Þk2 where fð0Þ is the initial state and can be given in advance。 Furthermore, /m – 0 by Claim
qffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi2ffi
1。 Thus, we have 0 < j/mj 6 a2 þ ð1 — xÞ kfð0Þk2。
In order to obtain the minimum of Dðj/mjÞ, which is a nonlinear function for j/m j, two cases are considered: one is the set
qffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi2ffiffi
v1 ¼ fj/m j : 1 6 j/m j 6 a2 þ ð1 — xÞ kfð0Þk2 g while the other is the set v2 ¼ fj/m j : 0 < j/mj < 1g。 It is worth mentioning
that v1 ¼ ; if
qffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi2ffi
a2 þ ð1 — xÞ kfð0Þk2 < 1。 On the one hand, if v1 – ;, it is a compact set, for any j/mj 2 v1; Dðj/mjÞ – 0。 Hence,
k2 ¼ minj/m j2v1 Dðj/m jÞ exists, and is larger than zero。 On the other hand, if v1 ¼ ; or j/mj R v1, we have j/mj 2 v2, which im-
2 4a 2a
plies that j/m j1þa < 1。 Hence, j/m j1þa < j/mj
Let
。 In this case, Dðj/m jÞ > 1。
k ¼ ð
1 — xÞ2b2
q0
。 1。
·min k2; 2
ð25Þ
Since V ðtÞ is radially unbounded and V_ ðtÞ is negative definite, global finite-time stability holds。 Q
Remark 6。 From Theorem 1, one can see that the proposed continuous-time FPSO algorithm possesses a good tracking per- formance。 Especially, when pi ðtÞ is time-varying, the proposed continuous-time FPSO algorithm can always track pi ðtÞ over a finite-time interval, which enables this algorithm to efficiently deal with the problem of odor source localization。
Remark 7。 It should also be pointed out that Theorem 1 gives a convergence condition for the deterministic system, i。e。, a is a constant。 If a is a random number, Theorem 1 describes an expected convergence condition in the mean square。 气味源定位的有限时间粒子群算法英文文献和中文翻译(11):http://www.youerw.com/fanyi/lunwen_101498.html