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131.
Theoretical and Mathematical Physics - 相似文献
132.
ABSTRACT. Limiting adverse consequences of fishing on essential fish habitat has emerged as a key fishery management objective. The conventional approach to providing habitat protection is to create MPAs or marine reserves that prohibit all or certain types of fishing in specific areas. However, there may be more cost‐effective and flexible ways to provide habitat protection. We propose an individual habitat quota (IHQ) system for habitat conservation that would utilize economic incentives to achieve habitat conservation goals cost‐effectively. Individual quotas of habitat impact units (HIU) would be distributed to fishers with an aggregate quota set to maintain a target habitat “stock.” HIU use would be based on a proxy for marginal habitat damage. We use a dynamic, explicitly spatial fishery and habitat simulation model to explore how such a system might work. We examine how outcomes are affected by spatial heterogeneity in the fishery and the scale of habitat regulation. We find that the IHQ system is a highly cost‐effective means of ensuring a given level of habitat protection, but that spatial heterogeneity and the scale of regulation can have significant effects on the distribution of habitat protection. 相似文献
133.
Translated from Aktual'nye Voprosy Prikladnoi Matematiki, pp. 28–31, 1989. 相似文献
134.
135.
Approximate Conditions and Passage to the Limit in Sobolev Spaces over Thin and Composite Structures
S. E. Pastukhova 《Journal of Mathematical Sciences》2006,133(1):931-948
Approximate properties of variable measures compose a base of the two-scale convergence method with respect to a variable
measure, which is used in averaging on periodic thin and composite structures. The paper gives a survey of methods for verifying
approximate properties. The main focus is on studying composite measures, which have been little studied.
__________
Translated from Sovremennaya Matematika i Ee Prilozheniya (Contemporary Mathematics and Its Applications), Vol. 16, Partial
Differential Equations, 2004. 相似文献
136.
137.
138.
S.E. WRIGHTH. ATMOKO 《Journal of sound and vibration》2002,258(2):203-232
The paper considers the performance of multi-frequency, multi-channel, free field sound cancelling systems for the reduction of discrete frequency and periodic noise. The approach uses a method of directional active noise control. Large sound reductions from these systems have been made possible through: (a) synthetically generating the cancelling sound and synchronizing with the primary source; (b) automatic alignment of all stability regions of the control system and; (c) avoiding instability produced by these multi-channel systems. 相似文献
139.
E. Lodi Rizzini 《La Rivista del Nuovo Cimento (1969-1970)》1992,15(8):1-29
The nucleon-antinucleon (NN) annihilation process provides a fertile testing ground for microscopic hadron exchange and/or quark models. TheNN system offers a rich ensemble of annihilation channels, whose relative BRs provide strong constraints on dynamical models.
Recent experiments show that values of BRs display a significant dependence onL, S andI. These dynamical selection rules,i.e. the suppression of transitions alloweda priori by conservation of quantum numbers, provide key signatures of the annihilation mechanism, and suggest dynamical content beyond
simple statistical or flavour symmetry models. 相似文献
140.
E. G. Ryabova 《Computational Mathematics and Modeling》1992,3(1):30-35
Translated from Vychislitel'nye Kompleksy i Modelirovanie Slozhnykh Sistem, pp. 98–106, Moscow State University, 1989. 相似文献