• Journal of Environmental Science International
• /
• v.14 no.7
• /
• pp.629-637
• /
• 2005

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were investigated in soil and pine needle samples taken from 16 sites of industrial and residential areas in Changwon, Korea to assess their distribution levels and to suggest the influence of industrial activities, PCDDs/DFs levels in the soil samples ranged from 0.57 to 20.79 pg I-TEQ/g dry weight with a mean value of 4.20 pg I-TEQ/g dry weight. PCDDs/DFs levels in the pine needle samples ranged from 0.39 to 8.75 pg I-TEQ/g dry weight with a mean value of 4.09 pg I-TEQ/g dry weight. In both soil and pine needle samples, the PCDDs/DFs concentrations in the industrial area sites were higher than those in the residential area sites. Homologue profiles in pine needle samples showed different patterns compared with soil samples. Based on the results of principal component analysis (PCA), it was confirmed that pine needles reflected a direct influence from local potential sources of PCDDs/DFs, showing a much higher degree of reflection than in soils. Pine needles are very useful as an indicator for monitoring or estimating the contamination of PCDDs/DFs in other areas which have been impacted by point pollution sources.

• The Journal of Asian Finance, Economics and Business
• /
• v.7 no.9
• /
• pp.755-767
• /
• 2020

The objective of this study is to examine and provide guidelines for regional governments, communities, and the private sector in planning and implementing poverty-reduction activities that are more effective, efficient, and targeted. Besides, this research's specific aims are: 1) increasing the rate of regional economic growth through optimization of potential sources of local income, 2) increasing per-capita income, and 3) reducing poverty, unemployment, and social-economic inequality of the community. The study was conducted in North Morowali District, Central Sulawesi Province, Indonesia, in 2018-2019. The research approach used quantitative and qualitative descriptive analysis. Data sources include sources from the Focus Group Discussion (FGD) and Regional Statistics. The results of this study are based on the Millennium Development Goals (MDG's) indicators that there are four priority scales in poverty reduction, namely, Health and Infrastructure (Priority I), Education (Priority II), Food stability (Priority III), and Population and Employment (Priority IV). Therefore, as a solution to poverty alleviation strategies, the cost approach through regional economic optimization and local income sources and community empowerment factors are essential. Apart from that, the involvement between elements (government, organizations, society, universities, and institutions) is expected to continue as an effort to realize poverty reduction can be optimally overcome.

• Journal of Korean Society for Atmospheric Environment
• /
• v.22 no.1
• /
• pp.135-143
• /
• 2006

The objective of this study is to develop PSCF (potential source contribution function) program and determine the optimal values of control parameters to enhance the prediction of PSCF modeling. This study provides an important information and methodologies that can be used to get better results of locating influencing sources, especially unknown and fugitive sources. To determine proper values of control parameters in PSCF model, the diagnostic assessment on the results obtained by the various input conditions was carried out. PSCF model has created and improved from version 1.0 to version 7.0 since 200 I and the measured data (at least > 100) of receptor, and the values of control input parameters should be arranged and determined to obtain reliable results in PSCF modeling. The size of modeling domain must be determined to include enough trajectories to get reliable results. And the size of grid is recommended to be 2.5 $\sim$ 5 degrees for global scale, 0.2 $\sim$ 1 degrees for regional scale and 0.05 degree for local scale.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1996.11a
• /
• pp.743-747
• /
• 1996

A Potential Field Method is applied to the proposed algorithm for the planning of collision-free paths of redundant manipulators. The planning is carried out on the base of kinematic configuration. To make repulsive potentials, sources are distributed on the boundaries of obstacles. To escape from local minimum of the main potential and to attack other difficulties of the planning, various potentials are defined simultaneously, Inverse Kinematics Problems of the redundant manipulators are solved by unconstrained optimization method. Computer simulation result of the path planning is presented.

• Applied Chemistry for Engineering
• /
• v.26 no.2
• /
• pp.178-183
• /
• 2015

Biomass is recognized as one of important renewable energy sources because it can be converted and used as solid, gaseous and liquid forms. Also, biomass is one of promising ways to solve the depletion of fossil fuels and global warming problems. The information about local biomass energy potentials and space energy densities can be powerfully utilized to determine the scale of biomass energy conversion plant and to analyze economic effects. The latest data on domestic biomass resources, such as agricultural, forestry, livestock and urban wastes, were collected from various government organizations and institutes and were analyzed to calculate biomass energy potential and space energy density. As local areas in South Korea to collect biomass resources increased, energy potentials increased, but space energy densities of total biomass decreased.

• Journal of Information Processing Systems
• /
• v.14 no.2
• /
• pp.448-454
• /
• 2018

Artificial bee colony (ABC) algorithm has attracted significant interests recently for solving the multivariate optimization problem. However, it still faces insufficiency of slow convergence speed and poor local search ability. Therefore, in this paper, a modified ABC algorithm with bees' number reallocation and new search equation is proposed to tackle this drawback. In particular, to enhance solution accuracy, more bees in the population are assigned to execute local searches around food sources. Moreover, elite vectors are adopted to guide the bees, with which the algorithm could converge to the potential global optimal position rapidly. A series of classical benchmark functions for frequency-modulated sound waves are adopted to validate the performance of the modified ABC algorithm. Experimental results are provided to show the significant performance improvement of our proposed algorithm over the traditional version.

• Journal of Agricultural Extension & Community Development
• /
• v.11 no.2
• /
• pp.251-265
• /
• 2004

The agricultural sector's economic structure in Korea is regarded to encounter major barriers on the way toward revitalizing its economic prosperity. Among many, the energy-related problem is one of prime nuclei embedded in the country's agricultural sector. The ought-to-come structural changes in the country's agricultural energy system hinge upon the central government's policy direction as well as efforts of local governments and local farming community members. The indirect aids via 'cross subsidy' of electricity tariff rate and 'tax-exempt price' of oil fuels are two notable causes of the unsustainable energy consumption pattern in the country's agricultural sector. As measures, demand-side management(DSM) and energy-efficiency promotions are regarded to be the most attractive methods for energy conservation and economic productivity as well. Development of renewable energy sources are also receiving a great deal of attention for the long-term alternatives to the country's existing oil-based agricultural production mode. This study examines the contributive potential of DSM approaches and renewables-based technologies. With the critical evaluation on the concurrent adversities of the country's agricultural energy system, various sources of renewable energy-solar power, wind power, biomass, etc.-are examined for the purpose of technological and economical viability. As sufficient potentials of renewable energy sources are being estimated, both the system production cost and the installation cost for the county's rural areas are expected to lower in the long term. DSM options are also evaluated to be fruitful even in the short term. Both the public and civil arenas must galvanise each side's effort in order to promote these policy options and community potentials.

• Journal of Korean Society for Atmospheric Environment
• /
• v.25 no.4
• /
• pp.275-288
• /
• 2009

The Korean government strengthened the environmental polices to manage and enhance Metropolitan Area air quality, and also has enforced "Special Act on Seoul Metropolitan Air Quality Improvement (SASMAQI)" issued in Dec. 2004. Recently government expanded the Seoul Metropolitan Air Quality Management District (SMAQMD) to the outskirts satellite cities of Seoul area through the "Revised Law Draft of SASMAQI". The SMAQMD has been alloted the allowable emission loads to the local governments on the basis of the carrying $PM_{10}$ capacity. However, in order to establish the effective air quality control strategy for $PM_{10}$, it is necessary to understand the corresponding sources which have a potential to directly impact ambient $PM_{10}$ concentration. To deal with the situations, many receptor methodologies have been developed to identify the origins of pollutants and to determine the contributions of sources of interests. The objective of this study was to extensively identify $PM_{10}$ sources and to estimate their contributions at the metropolitan area. $PM_{10}$ samples were simultaneously collected at the 3 semi-industrialized local cities in the Seoul metropolitan area such as Hwasung-si, Paju-si, and Icheon-si sites from April 15 to May 31, 2007. The samples collected on the teflon membrane filter by one $PM_{10}$ cyclone sampler were analyzed for trace metals and soluble ions and samples on the quartz fiber filter by another sampler were analyzed for OC and EC. Source apportionment study was then performed by using a positive matrix factorization (PMF) receptor model. A total of 6 sources were identified and their contributions were estimated in each monitoring site. Contribution results on Hwasung, Paju, and Icheon sites were as follows: 33%, 27%, and 27% from soil source, 26%, 26%, and 21% from secondary aerosol source, 11%, 11%, and 12% from biomass burning, 12%, 6%, and 5% from sea salt, 7%, 15%, and 19% from industrial related source, and finally 11%, 15%, and 16% from mobile and oil complex source, respectively. This study provides information on the major sources affecting air quality in the receptor sites and thus it will help to manage the ambient air quality in the metropolitan area by establishing reasonable control strategies, especially for the anthropogenic emission sources.

• Journal of Environmental Health Sciences
• /
• v.50 no.4
• /
• pp.257-266
• /
• 2024

Background: Exposure to fine particulate matter (PM_2.5) and ozone (O₃) poses potential health risks. The Indoor-to-Outdoor ratio (I/O ratio) is a valuable tool for understanding indoor air quality and identifying potential indoor sources. Objectives: The objective of this study was to determine I/O ratios of PM_2.5 and O₃ by different microenvironments and seasons in Korea. Methods: From December 2021 to November 2023, indoor concentrations of PM_2.5 and O₃ were monitored every hour in 13 microenvironments (residential indoor, office, school, restaurant, pub, café, study café, private educational institute, PC room, billiard room, screen golf center, supermarket, and shopping mall) in Korea. Hourly outdoor concentrations of PM_2.5 and O₃ were obtained from local air quality monitoring stations, provided by airkorea.or.kr. The hourly I/O ratio was calculated by the indoor and outdoor concentrations. Results: At the pub, billiard room, and PC room, the median PM_2.5 I/O ratio exceeded 1 in all seasons, except in spring at the PC room (0.9), suggesting indoor smoking as a potential cause. The median PM_2.5 I/O ratio at the restaurant exceeded 1 in winter, autumn, and summer, except for spring (0.9), indicating significant PM_2.5 emission sources in the restaurant. The median O₃ I/O ratio was below 0.5 in all seasons and microenvironments. Conclusions: This study provided useful data on relationships between indoor and outdoor pollution in various microenvironments by seasons. These I/O ratios could be applied for more accurate exposure assessment to protect health of human.

• Journal of Ecology and Environment
• /
• v.48 no.2
• /
• pp.182-195
• /
• 2024

Background: Invasive alien plant species (IAP) significantly threaten Nepal's protected areas and local communities. Understanding their distribution, impact, management, and utilization is essential for developing effective management strategies and sustainable utilization practices. The systematic literature review of publications from 2010 to 2023. The search was conducted through the database Nepal Journal online database (NepJOL) and Google Scholar, yielding an initial pool of 4,304 publication. After applying inclusion and exclusion criteria; we meticulously reviewed 43 articles for data extraction. Results: Seventeen IAP are found in protected area, Nepal with the highest prevalence observed in Koshi Tappu Wildlife Reserve, followed by Chitwan and Sukhlaphanta National Park. The most problematic species in terrestrial ecosystems are Mikania micrantha, Lantana camara, and Chromolaena odorata. The grassland ecosystems of wildlife habitats, primarily in the Terai and Siwalik regions, are the most invaded. Various management approaches are employed to mitigate the spread and impact of IAP, including mechanical methods such as uprooting, burning, and cutting. However, these methods are costly, and context-specific interventions are needed. The study also explores the potential use of IAP for economic, ecological, or cultural purposes, such as medicinal properties, energy production potential, and economic viability. Local communities utilize these plants for animal bedding, mulching, green manure, briquette, and charcoal production. Conclusions: Applying silvicultural practices alongside mechanical management is recommended to maintain a healthy terrestrial ecosystem and utilize the removed biomass for valuable products, thereby reducing removal costs and increasing income sources, potentially benefitting both local communities and wildlife in protected areas.