A modification of the logistic equation is critically analysed and its application to competition between sexual and asexual populations presented. Such a model of competition can be a formal representation of the tangled bank hypothesis of the evolution and maintenance of sexuality. It shows that the elimination of asexual individuals by sexual ones is possible only if the size of the habitat ...

We consider a class of evolution equations describing population dynamics in the presence of a carrying capacity depending on the population with delay. In an earlier work, we presented an exhaustive classification of the logistic equation where the carrying capacity is linearly dependent on the population with a time delay, which we refer to as the “linear delayed carrying capacity” model. Her...

1. Current Views of Global Carrying Capacity 2. The Global Social, Economic, and Cultural Situation 2.1. Economic Differences 2.2. Cultural Differences 2.3. A Comparison of Production and Consumption between Developed and Developing Countries 3. Carrying Capacity of Natural Resources 4. The Environment, Environmental Problems, and Environmental Protection 5. Population, Resources, and Environme...

Nat iona l and international economic policy has usually ignored the environment. In areas where the environment is beginning to impinge on policy, as in the General Agreement on Tariffs and Trade (GATT) and the North American Free Trade Agreement (NAFTA), it remains a tangential concern, and the presumption is often made that economic growth and economic liberalization (including the liberaliz...

in this paper, static performance characteristics for a finite lenght two-lobe journal bearing lubricated with micropolar fluid is studied. using finite element method, steady-state film pressure is obtained by solving modified reynolds equation, based on micropolar lubrication theory. with the help of film pressure in bearing, the static performance characteristics in terms of load carrying ca...

in this paper the problem on “magnetic fluid lubrication of porous-pivoted slider bearing with slip velocity by n ahmad et.al.[7]” has been recapitulated using jenkin’s model [4] with the additional effect of squeeze velocity of the above plate. it is found that while discussing the above problem, [7] has stated but ignored the term , where +, in their study (refer equation(2.2)). this paper re...

This paper attempts to establish an evaluating index system of land comprehensive carrying capacity in Xi'an city involving three aspects, such as economic carrying capacity, social carrying capacity, and ecological carrying capacity, combined with the development goals and constraint factors of Xi'an city. Furthermore, we adopted the method of mean-squared deviation weight decision to evaluate...

Based on the theory of ecological footprint, and as land use/cover change the breakthrough point in Loess hilly area, the ecological carrying capacity analysis method was used to calculate the ecological carrying capacity of Shanghuang experimental area. The results showed that the total ecological carrying capacity in 1982, 2000 and 2010 were 242.47、750.53、929.68 hm. Meanwhile the per capita e...