092-802-3434

092-802-3432

Doctor of Engineering

Environmental Systems Engineering

Dr. Nakayama has been conducting following research topics.

1.Economic development and environmental issues in Asian countries
Since the adoption of reforming and opening policy, rapid industrialization and urbanization have taken place in Asian countries, accompanying the increasing generation of air and water pollutants. Development patterns and environmental conditions, however, differ significantly between regions. This study conducted a statistical analysis of regional characteristics of industrial development and air and water pollutant emission structures of cities in Asian countries. The DPSER(Driving Force-Pressure-State-Effect-Response) Model is adopted to analyze the relationships of the economic and environmental factors concerned. Then, pollutants emission structures of cities are compared between regions in which they are located, identifying the dominant characteristics of each region and demonstrating the contrast between the regions.
Dr. Nakayama participated in a project "Urban Policy Integration of Energy Related Environmental Issues in Selected Asian Mega-cities" as visiting researcher of the Institute for Global Environmental Strategies (IGES) in 2002-2003.


2. Environmental accounting for assessment of urban metabolism
Based on a method of environmental accounting, this study attempted to develop of a framework that can describe efficiency of waste disposal service at municipal solid waste landfill sites. Pollutants in landfilled waste are stocked in a landfill site for a certain period. A part of stocked pollutants dissolve into the rain water as leachate flow and is gathered by leachate collection pipes to be treated. A part is decomposed by microbes and then discharged as landfill gas flow. Final disposal service have a function to isolate pollutants in the waste from a natural environment until the stocked waste stabilizes to harmless, function to treat the pollutants generated as flow. This paper proposed the frame of environmental accounting from above noted viewpoints. Then, a final disposal service in a city was evaluated as a case study.

3. Remote Sensing for Landfill Monitoring
To meet the needs of disposing of large amounts of waste discharge, large-scale landfill have been constructed in Asian mega-cities. For example, Laogang landfill is one of the largest landfill sites in China and has more than 300 ha landfill area. In such large landfill, there are high costs and much manpower involved in monitoring and managing the landfill. Moreover, present methods of landfill monitoring, which are made at several points at a frequency that seems appropriate to the investigator, has difficulties in statistically extrapolating results and deducing quantitative results for the whole area. Especially, due to the inhomogeneous properties of landfilled waste, it is difficult to understand the situation of the entire landfill by limited information acquired from point surveys. In order to solve this problem, a preliminary survey, which can provide data with spatial distribution, is required to be done before the detail point surveys. Satellite remote sensing is one method that can help to solve the above noted problems. In this study, it was employed to develop a preliminary survey method of large-scale landfill monitoring.

Research Interests

• Economic development and environmental issues in Asian countries
  keyword : East Asia, Economic decelopment, Environmental problems
  2000.03.
• Environmental accounting for assessment of urban metabolism
  keyword : Urban metabolism, environmental accounting
  2005.04.
• Remote Sensing for Landfill Monitoring
  keyword : Waste, Landfill, Illegal dumping, Remote sensing
  2001.04.

Current and Past Project

• The East Asian countries, especially China, have achieved rapid economic growth, which currently play important roles of the demand and supply in the whole world. However, they have actually caused serious environmental destruction paralleled with the mass industrial production. Typical examples include air pollution in the Beijing and Shanghai areas and water pollution in the Chang and Yellow Rivers. Environmental destruction in China might expand air and marine pollution not only in Japan but also East Asia. In consequence, it could cause global environmental changes as “Cross-Border Pollution”.
  There is no border for the environmental problems. All we should solve these problems together, even if they are not own national issues. It is important to keep the mutually beneficial relationship among the East Asian countries. Fortunately, Japan, the neighboring country of China, has advanced environmental technologies and brilliant scientists at the world level, since we had overcome various pollutions during the high economic growth. China’s proactive role is of paramount importance. The only solution is to work together with Japan, Korea, and China.
  From this view, Kyushu University decided to organize “The East Asian Environmental Problems (EAEP) Project team” on September 2007 under the direction of Tisato Kajiyama, President, which is formed by the top-level environmental scientists in Kyushu University. Then, the 1st Kick-Off International Symposium was held in Fukuoka November in the same year; the participants from each country strongly decided to solve the environmental issues together.
  
• The amount of resources and energy used in the field of "dwelling" in Japan is increasing. Environment loads are increasing markedly, so the formation of dwelling spaces that maintain affluence while considering the environment is necessary.
  The purpose of this research is to examine methods of evaluating the affluence of habitats by gaining an understanding of the current status of housing and other "dwelling"-related facilities and equipment. In concrete terms, this involves examination of targets thought necessary to an evaluation of affluence and basic investigation of accounting system construction in order to quantitatively grasp the value of "dwelling"-related facilities and the environment loads derived therefrom. The investigation is performed with the following three questions for indices in mind: (1) is there a need for the index, (2) does it maintain objectivity, and (3) are statistics available.
• Based on a method of environmental accounting, this study attempted to develop of a framework that can describe efficiency of waste disposal service at municipal solid waste landfill sites. Pollutants in landfilled waste are stocked in a landfill site for a certain period. A part of stocked pollutants dissolve into the rain water as leachate flow and is gathered by leachate collection pipes to be treated. A part is decomposed by microbes and then discharged as landfill gas flow. Final disposal service have a function to isolate pollutants in the waste from a natural environment until the stocked waste stabilizes to harmless, function to treat the pollutants generated as flow. This paper proposed the frame of environmental accounting from above noted viewpoints. Then, a final disposal service in a city was evaluated as a case study.
• To meet the needs of disposing of large amounts of waste discharge, large-scale landfill have been constructed in Asian mega-cities. For example, Laogang landfill is one of the largest landfill sites in China and has more than 300 ha landfill area. In such large landfill, there are high costs and much manpower involved in monitoring and managing the landfill. Moreover, present methods of landfill monitoring, which are made at several points at a frequency that seems appropriate to the investigator, has difficulties in statistically extrapolating results and deducing quantitative results for the whole area. Especially, due to the inhomogeneous properties of landfilled waste, it is difficult to understand the situation of the entire landfill by limited information acquired from point surveys. In order to solve this problem, a preliminary survey, which can provide data with spatial distribution, is required to be done before the detail point surveys. Satellite remote sensing is one method that can help to solve the above noted problems. In this study, it was employed to develop a preliminary survey method of large-scale landfill monitoring.
• Geomembrane liner sheets can be inspected for degradation by performing destructive tests where small samples are cut from the sheets and examined using strength testing. However cutting out samples compromises the most important function of liner sheets which is to prevent water leakage and ideally should not be performed. The aim of this study is to develop an on-site non-destructive testing method to detect the degradation of geomembrane liner sheets at a landfill site using visible near-infrared (VNIR) spectroscopy. The author shows that the reflectance spectrum of a geomembrane changes at particular wavelengths after the geomembrane has been soaked in chemicals, and there is a correlation between the change of reflectance spectrum and the change of strength, stretch and weight of the geomembrane. The author also explains the mechanism of degradation of the geomembrane by using a microscope and FTIR analysis. Geomembrane degradation occurs when the plasticizer and filling material dissolves from the main body of geomembrane, causing a change in the VNIR spectrum.
• There are possibilities on remote sensing for the use of waste management. One of them is the detection of illegal waste dumping by using satellite remote sensing images. In Japan, the amount of illegally dumped waste has been increasing due to the increase of the cost for waste treatment and lack of the capacity in landfill sites. Municipalities worry about the pollution caused by such illegal dumping and require an effective tool to detect dumped waste. Dr. Nakayama was involved in the research on detection of illegal dumping to meet this urgent need.
  The change of the reflectance pattern of EM might occur in which waste had dumped on the ground (e.g. grassland, bare land). If this change can be detected by the remote sensing sensor on the satellite platform, illegal dumping sites may be found easer than present method.
• Since the adoption of reforming and opening policy, rapid industrialization and urbanization have taken place in Asian countries, accompanying the increasing generation of air and water pollutants. Development patterns and environmental conditions, however, differ significantly between regions. This study conducted a statistical analysis of regional characteristics of industrial development and air and water pollutant emission structures of cities in Asian countries. The DPSER(Driving Force-Pressure-State-Effect-Response) Model is adopted to analyze the relationships of the economic and environmental factors concerned. Then, pollutants emission structures of cities are compared between regions in which they are located, identifying the dominant characteristics of each region and demonstrating the contrast between the regions.
  Dr. Nakayama participated in a project "Urban Policy Integration of Energy Related Environmental Issues in Selected Asian Mega-cities" as visiting researcher of the Institute for Global Environmental Strategies (IGES) in 2002-2003.

Academic Activities

Educational Activities