• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.21 no.1
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• pp.1-10
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• 2011

Generally, the tire curing process is the process in which the sulfur is added and subsequently the tire is heated to give the tire elasticity. In this process, all kinds of the chemicals in the tire are emitted with a lot of heat. The chemical fume and heat aggravate the work environment. To solve this problem, 92 local exhaust ventilators and 8 gravity ventilators were used, but not satisfactory yet. Preliminary survey showed that the temperatures in the process were very high: 30.3, 32.9 and $37.2^{\circ}C$ at 2, 4 and 6m above the ground level, respectively in the winter (outside temperature was $2^{\circ}C$). It can be imagined that the process is severely hot in the summer time. The higher temperature distribution in the higher space tells us that the hot plume could not be removed with the existing ventilation systems. Therefore, in this study, some alternative ventilation systems were designed. The partitions were used to contain the hot plume to increase the capture efficiency. The gravity ventilators were newly designed to improve the extraction efficiency of hot fume. To satisfy the balance of pressure in the curing process, some supply air system was introduced by renewing the existing air conditioning system. Many alternative solutions were evaluated by using computational fluid dynamics modelling. The best and applicable solution was selected and the existing ventilation system was modified. After implementing the new ventilation system, the hot environment was much improved. The temperature reduction in the curing process was about $6.4^{\circ}C$.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.2169-2175
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• 2009

This research aims to evaluate the concept of eco-efficient water infrastructure and provides a list of case studies in order to help understand the applicability of eco-efficient water infrastructure to Asia and the Pacific. A set of indicators have been explored to assess eco-efficiency in water infrastructure for the region on a micro and macro scale. The core idea of eco-efficiency, 'more value with less impact (on the environment)', has proven to be applicable in management of water infrastructure. The fundamental elements in eco-efficient water infrastructure should encompass physical infrastructure and non-physical infrastructure, which is more needed particularly in Asian countries. The case studies have demonstrated the applicability of the concept of eco-efficient water infrastructure. The Republic of Korea has provided the case of the eco-friendly approaches to enhance dam management and its innovative solutions how to use water more efficiently through state-of-art technologies. The experiences of Singapore are some of the best evidence to establish eco-efficient water infrastructure, for instance, the NEWater project via application of cutting edge technologies (recycled water) and institutional reform in water tariff systems to conserve water as well as enhance water quality. A list of indicators to assess eco-efficiency in water infrastructure have been discussed, and the research presents a myriad of project cases which are good to represent eco-efficiency in water infrastructure, including multipurpose small dams, customized flood defense systems, eco-efficient ground water use, and eco-efficient desalination plants. The study has presented numerous indicators in five different categories: 1) the status of water availability and infrastructure; 2) production and consumption patterns of freshwater; 3) agricultural products and sources of environmental loads; 4) damages from water-caused natural disaster; and 5) urban water supply and sanitation. There are challenges as well as benefits in such indicators, since the indicators should be applied very carefully in accordance with specific socio-economic, political and policy contexts in different countries in Asia and the Pacific Region. The key to success of establishment of eco-efficient water infrastructure in Asia primarily depends on the extent to which each country is committed to balancing its development of physical as well as non-physical water infrastructure. Particularly, it is imperative for Asian countries to transform its policy focus from physical infrastructure to non-physical infrastructure. Such shift will help lead to implementation of sustainable in Asian countries.

• Environmental and Resource Economics Review
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• v.19 no.3
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• pp.597-632
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• 2010

There is general agreement that global warming is occurring and that the main contributor to this probably is the buildup of green house gasses, GHG, in the atmosphere. Two main contributors are the utilization of fossil fuels and the deforestation of many regions of the world. The burning of fossil fuels increases atmospheric carbon while the burning of fuel-wood reducing fossil fuel consumption along with its forest source maintain an atmospheric carbon level. The standing timber in the forests is a carbon sink, as are wood buildings and structures, and fossil fuel in the ground. This paper is designed to examine a number of current issues related to mitigating the global warming problem through forestry. For this purpose, we develop a modeling approach by integrating timber market, fossil fuel market and carbon cycling model. We use discrete time optimal control theory to identify optimal time paths, the laws of motion, and stationary stats solutions of endogenous variables in the model. On the basis of these results, we identify the optimal amounts of subsidies to be provided or taxes to be imposed by the regulatory agency to mitigate atmospheric carbon accumulation. We also present a numerical example to help illustrate the characteristics of variables in the model when the social cost for atmospheric carbon incrementally shifts upward. A surprising result is that the social cost function for atmospheric carbon has a very smaller impact on the optimal rotation period than previous literature suggested.