Introduction
The rapid growth of human population in conjunction with remarkable change in the life style of people, had led to serious socio-environmental problems, including solid waste management, in the third world countries. The situation is worse in the metropolises, where the population density is far higher than the threshold limit. Solid waste management in these cities is no longer just an intangible threat as more and more streets are getting filled with garbage, thereby putting the public at great health risk.
Economics of waste logistics
Consequently, in the last decades, management of wastes has evolved as a complex discipline. Collection and transport are the two main operations of waste management that expend maximum resources, both in terms of man power and infra structure. In the developing countries like India, these two operations utilize almost the entire funds allocated for waste management. This is because, the wastes are neither treated nor disposed off safely, rather dumped indiscriminately on water bodies as well as open lands and burnt to save space. Hence, while budgeting for solid waste management, meager or no money is allocated for the treatment or disposal. Nevertheless, major share goes only for collection and transport of waste. The vehicles generally used for municipal solid waste collection and transportation are not suited to the road and traffic conditions of the cities. The problem, difficult per se, is further complicated by the dilapidated condition of the vehicles which cause severe economical and environmental damage. The fuel consumption does not commensurate with the distance traveled, thus adding a large sum of money to the recurring costs.
Vehicle routing
In this situation, optimization of the movement of waste collection vehicles becomes an imperative need. However, conventionally the route plan of the waste collection vehicles is manually worked out by the drivers on a trial and error basis. With the rate of waste generation ever increasing and vehicular traffic on the roads becoming extremely congested, manual planning of waste collection could only yield severely inefficient solutions. At this juncture, the need for a computer based solution which can optimize the vehicle routing and in doing so could significantly moderate the overall costs incurred on the collection and transportation of solid waste.
Hybrid Algorithms for Waste Kinematics
Having this in mind, a hybrid algorithm-based computer solution, named as HAWK (Hybrid Algorithms for Waste Kinematics) was developed by the authors, specifically to address the problem of waste logistics in the developing countries. The concept of HAWK is not only restricted for the transportation of waste, rather with necessary refinement could be applied across disciplines, ranging from airport baggage handling to supply chain management. The analytical methodology of HAWK was expounded with its application to a real case, Pondicherry Engineering College.