Exploring the resource recovery potentials of municipal solid waste: a review of solid wastes composting in developing countries

Population explosion, high urbanization and improved living standards have induced rapid changes in quantities and materiacompositions of solid waste generation globally. Until recently solid waste disposal in landfills and open dump sites waconsidered more economical and it is the most widely used methods in developing countries. Hence the potentials in the othealternative methods such as the resource recovery and recycling and their integration into waste management have been scarcelassessed. However, the ever growing challenges posed by the rapidly increasing quantities and compositions of solid wastes ideveloping countries led to the searching for alternative waste disposal methods. In this regard the paper presented an assessmenof the resource potentials of municipal solid waste materials arising from cities in developing countries as a strategy fosustainable solid waste management. Using published data on solid waste composition the paper has identified that there is higpotentials of composting in the solid waste stream from cities in developing countries. In conclusion, it recommended the recoverof organic waste material and papers for composting and the recycling of plastic, metals, textiles and others to explore their resource recovery potentials. This will largely reduce the ultimate quantities of solid waste for disposal and lower the operatincosts. This strategy will achieve sustainable waste management in developing countries. It is hoped that the paper has provided useful guide for wastes management policy decisions in developing countries

A Review of Norms and Normative Multiagent Systems

Norms and normative multiagent systems have become the subjects of interest for many researchers. Such interest is caused by the need for agents to exploit the norms in enhancing their performance in a community. The term norm is used to characterize the behaviours of community members. The concept of normative multiagent systems is used to facilitate collaboration and coordination among social groups of agents. Many researches have been conducted on norms that investigate the fundamental concepts, definitions, classification, and types of norms and normative multiagent systems including normative architectures and normative processes. However, very few researches have been found to comprehensively study and analyze the literature in advancing the current state of norms and normative multiagent systems. Consequently, this paper attempts to present the current state of research on norms and normative multiagent systems and propose a norm’s life cycle model based on the review of the literature. Subsequently, this paper highlights the significant areas for future work

Normative systems represented as hybrid knowledge bases

Abstract. Normative systems have been advocated as an effective tool to regulate interaction in multi-agent systems. Logic programming rules intuitively correspond to conditional norms, and their semantics is based on the closed world assumption, which allows default negation, often used in norms. However, there are cases where the closed world assumption is clearly not adequate, and others that require reasoning about unknown individuals, which is not possible in logic programming. On the other hand, description logics are based on the open world assumption and support reasoning about unknown individuals, but do not support default negation. In this paper, we demonstrate the need for the aforementioned features (closed and open world assumptions, and reasoning about unknown individuals) in order to model human laws, with examples from the Portuguese Penal Code. We advocate the use of hybrid knowledge bases combining rules and ontologies, which provide the joint expressivity of logic programming and description logics. We define a normative scenario as the pair of a set of facts and a set of norms, and give it a formal semantics by translation into an MKNF knowledge base. We describe the implementation of the language, which computes the relevant consequences of given facts and norms, and use it to establish the resulting sentence in a penal scenario.