This paper reports the results of an experimental investigation on the effect of the EGR on the pollutants emission, especially on oxides of nitrogen, from the exhaust gases and performance of the spark ignition engine. Also along with experimental work, a mathematical model for the determination of the effect of EGR on the peak cycle temperature and for the prediction of its effect on the NOx ...

Learning about Recycling and Reuse through Pre-School Games S.M. Shobeyri, Ph.D. H. Meybodi A. Saraadipoor S. Rashidi Environmental education is the most fundamental approach to environmental protection and can begin from the pre-school level and through the use of games. To show the effectiveness of this approach, a random sample of 30 preschoolers of ages 5 and 6 was se...

Two models for competition of two populations in a chemostat environment with nutrient recycling are considered. In the first model, the recycling is instantaneous, whereas in the second, the recycling is delayed. For each model an equilibrium analysis is carried out, and persistence criteria are obtained. This paper extends the work done by Beretta et al. (1990) for a single species.

“why” mind-set. We are particularly interested in your thoughts about recycling. In particular, we are interested in your thoughts about why you would recycle. For example, what are the underlying reasons for recycling, for what purpose would you recycle, etc.? Please take some time below to explain why you would go about recycling.

In this paper we improve a model checking algorithm based on the tableau method of Stifling and Walker. The algorithm proves whether a property expressed in the modal mu-calculus holds for a state in a finite transition system. It makes subsequent use of subtableaux which were calculated earlier in the proof run. These aubtab|eaux are reduced to expressions. Examples show that both size of tabl...

programs, as goals as part of general public policy, and as regulatory tools in permit processes. Therefore, the computation of a recycling rate for a particular program, region, or waste stream is often of public interest or may have legal implications. It is not clear that the rates reported to the public are the most appropriate. Municipalities may not report all the recycling credits they c...

Cascading trophic interactions mediated by consumers are complex phenomena, which encompass many direct and indirect effects. Nonetheless, most experiments and theory on the topic focus uniquely on the indirect, positive effects of predators on producers via regulation of herbivores. Empirical research in aquatic ecosystems, however, demonstrate that the indirect, positive effects of consumer-m...

This study aims at evaluating the environmental impacts stemmed from End-of-Life Vehicle (ELV) treatment system in Korea, using Life Cycle Assessment (LCA) method. In the process of the assessment, not only the environmental burdens originated from ELV dismantling processes and recycling processes but also the environment benefits obtained from the avoided effects of recycled materials on the e...