• Journal of the Korea Organic Resources Recycling Association
• /
• v.3 no.1
• /
• pp.43-59
• /
• 1995

Composting of muicipal waste is essential to achieve high national reading rate exceeding 20% to encourage composting activity, intensive education and qublic information activity for residents are necessary. More developed countries such as Europe and America, some effecient and systematic education program were developed and gained considerake success. In this paper we analyzed the edacation and public information program in USA and Germany. And then, we suggested schematic program of education and public information for composting.

• Journal of environmental and Sanitary engineering
• /
• v.2 no.2 s.2
• /
• pp.69-78
• /
• 1987

Due to the increase of population and development of industry, the demand of available water resources increased . Many reservoirs have been constructed in large scales to meet this urgent need , resulting in the increased amount of water resources. After the constructions, however, serious pollution-especially eutrophication-in some reservoirs become a socialaffair. Therefore, water quality control in these resources should be considered more intensively than any other environmental preservation policies. It also seems to be imminent to prepare the precautionary steps. Most water pollution in Korea-73 percent - can be traced to domestic sewage. It may rome as a surprise to Some, Industry is responsible for just 27 percent of ]Korea's water pollution. What he calls 'non-point' Sources, which may include agricultural Chemicals, Create only negligible amount of water pollution. Up to $15\%$ of domestic sewage is treated in Korea, which is quite low when compared with the waste processing in developed countries. So it is the most urgent matter to control the pollution sources. One of the precautionary plans, more urban domestic sewage treatment plants must be installed and operated efficiently. It is known that nutrients such as nitrogen and phosphorous are the major factors the process of eutrophication, which can be removed majorly by the tertiary or advanced treatment process.

• Journal of Soil and Groundwater Environment
• /
• v.27 no.2
• /
• pp.41-49
• /
• 2022

To abate the environmental burdens arising from CO₂ emissions, biochar offers a strategic means to sequester carbons due to its recalcitrant nature. Also, biochar has a great potential for the use as carbon-based adsorbent because it is a porous material. As such, developing the surface properties of biochar increases a chance to produce biochar with great adsorption performance. Given that biochar is a byproduct in biomass pyrolysis, characteristics of biochar are contingent on pyrolysis operating parameters. In this respect, this work focused on the investigation of surface properties of biochar by controlling temperature and reaction medium in pyrolysis of pine sawdust as case study. In particular, CO₂ was used as reaction medium in pyrolysis process. According to pyrolytic temperature, the surface properties of biochar were indeed developed by CO₂. The biochar engineered by CO₂ showed the improved capability on CO₂ sorption. In addition, CO₂ has an effect on energy recovery by enhancing syngas production. Thus, this study offers the functionality of CO₂ for converting biomass into engineered biochar as carbon-based adsorbent for CO₂ sorption while recovering energy as syngas.

• Tunnel and Underground Space
• /
• v.31 no.1
• /
• pp.1-9
• /
• 2021

Recently, the development of underground space has been accelerated with rapid urbanization, and it is significantly important for safe construction to accurately understand the geological conditions of the section when excavating rocks. In this paper, a boring alignment tracking and geological exploration system have been developed to identify the geological conditions beyond the excavation face by utilizing a MSP method that bores a large empty hole to reduce blast-induced vibration. The major advantage of the proposed exploration system is that we can obtain the ground condition of 50 m ahead of the excavation face through exploration along blast cut-holes drilled for the NATM tunnel construction. In addition, we introduce several case histories regarding the assessment of the geological conditions beyond the tunnel face by monitoring the inside of large empty holes using the proposed hole exploration system.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2023.05a
• /
• pp.431-431
• /
• 2023

In recent decades, the socio-hydrology community has developed several socio-hydrological frameworks to understand the complexity of the coupled human-water system. Although there have been efforts to relate sociology and hydrology, there still have been some insights that remain debatable. As for this study, the Value-belief-norm theory was used to represent the human behavior in order to connect the human-water system. The theoretical framework of values, beliefs and norms was developed to understand the human culture towards the environment. In addition to the theory, norms are legislation of human behavior in the society while the values are the guiding principle to motivate beliefs and norms. The overview of this study implied on developing a socio-hydrological model consisting of the four systems defined as hydrology, socio-economy, technology and institutional. The interconnectors between the four systems are the key variables and parameters representing a module namely the causal loop diagram. Moreover, water quality, size of population, infrastructure capacity and norms are the key variables to connect the four systems. The developed model will be applied to Han River to represent the coevolutionary of the dynamics of human-water systems.

• Journal of Korea Water Resources Association
• /
• v.55 no.5
• /
• pp.383-392
• /
• 2022

The restoration of the Nakdong River estuary is one of the most important projects of the Ministry of Environment, Republic of Korea. A real-scale experiment of gate operation was executed from 2019 to 2020, and a pilot operation was performed in 2021. The gate of Nakdong River Estuary Barrier (NEB) is supposed to be continuously opened based on the experiment results. Many critical decisions should be made immediately during the experiment based on the real-time measured data and numerical analysis considering the seawater inflows. The decision-making sequence was made systematically with the accurate estimation of seawater inflow. The estimation of seawater inflow is the main research objective and the equations of seawater inflow were developed, reflecting the structural characteristics of NEB. The inflow equations were developed in two forms, overflow and underflow. ADCP (Acoustic Doppler Current Profiler) was used to measure seawater inflow, check the accuracy of the developed equations, and derive the flow coefficient. The comparison error of the developed equations was about 3% compared to the measured data.

• The Journal of Asian Finance, Economics and Business
• /
• v.9 no.2
• /
• pp.209-215
• /
• 2022

This study aims to analyze the livelihood resources and income diversification of informal recyclers in the Mekong River Delta (MRD). The multiple linear regression model was applied to determine income diversification and total household income with the sustainable livelihood analysis framework developed by the United Kingdom Department for International Development (2000), including human resources, physical resources, natural resources, financial resources, and social resources. The results indicated that up to 25% of itinerant waste buyers worked on average more than 7.3 hours/day, which was higher than the urban near-poor level regulated by the Vietnam government. The results of the regression model revealed that total households' income was affected by the factors of health status, gender, urban location type 1, the amount of potential savings, and informal credit participation, while the factors of health status, urban location, the amount of potential savings, and informal credit participation have the effect of diversifying farm household income. Thus, if the informal waste recycling sector is supported and regulated by proper government management, it will not only help poor households diversify their income, but it will also help poor households diversify their income, particularly women's income, which is vulnerable and lower than male income in the MRD.

• Resources Recycling
• /
• v.25 no.6
• /
• pp.3-12
• /
• 2016

In this study, Au distribution in F-PGA chip and W-BGA chip were examined to recover Au effectively from CPU chips. The result showed that 80.8% and 89.8% of Au exist in terminal of F-PGA chip and bare die of W-BGA chip, respectively. Based on the fact that Au exists in specific parts of the chips, an CPU chip dismantling apparatus was developed. The experimental variables were roller rotating speed, heat temperature of IR heater and heating time. Terminals of F-PGA chips were completely recovered under the temperature of $300^{\circ}C$ and the residence time of 90 s. Bare dies of W-BGA chips were completely recovered as well under the temperature of $300^{\circ}C$, the roller rotating rate of 90 rpm and the residence time of 90 s.

• Korean Journal of Organic Agriculture
• /
• v.11 no.3
• /
• pp.21-35
• /
• 2003

Environmental-friendly agriculture(EFA) has been mainly developed at many areas which have factors of natural, social cultural and economic characteristics. These rural areas can be developed into environmental-friendly space to preserve ecosystem, natural and cultural scenery, and environmental resources. The plan for developing a regional agriculture has to get central operating bodies, producers' organizations, a homogeneous district for farming, and so on. This case study is focused on development directions and situations of the EFA of Kosam area in Anseong. Kosam cooperatives is a central managing body to produce and sell rice by duck-farming method, and to develop rural area. This cooperatives is one of the leading those that have developed the regional agriculture in Korea. Kosam area is at a disadvantage of natural-geographical conditions and farming size. Kosam cooperatives has been trying to overcome these agricultural weaknesses by introducing duck-farming method. They have got many excellent results through developing EFA as a regional agriculture. Kosam area will be a good place for green tourism if they can actualize the combination model of three demand factors (natural and agricultural scenic view, natural-friendly recreation and safe food) for green tourism in the near future.

• Journal of Plant Biotechnology
• /
• v.36 no.3
• /
• pp.202-206
• /
• 2009

In many countries including China and U.S., researchers are developing methods to use sweetpotato as raw material for biofuel. We consider the sweetpotato is not only a source of green fuel, it eventually will provide various material including paper, adhesives, biodegradable plastics, and secondary metabolites. Sweetpotato is one of the high efficiency crop because it yields more calories per unit area than either maize or potato, and it requires the shortest growing cycle of the root crops grown in the tropics. Sweetpotato is the most useful crop for the coming starchbased industry era. Sweetpotato genetic resources are collected, characterized, evaluated, and maintained by U.S., China, Japan, and the International Potato Center. New varieties of sweetpotato using the proper genetic resources and molecular breeding will be developed to cope with the global food and energy in 21st century.