• Journal of Korean Society of Transportation
• /
• v.31 no.3
• /
• pp.55-64
• /
• 2013

Conventionally, greenhouse gas (GHG) emissions in the transport sector have been estimated using the fuel consumption (i.e. Tier 1 method). However, the GHG emissions on road networks may not be practically estimated using the Tier 1 method because it is not practical to monitor fuel consumption on a road segment. Further, air pollutant emissions on a road may not be estimated efficiently by the Tier 1 method either due to the diverse characteristics of vehicles, such as travel speed, vehicle type, model year, fuel type, etc. Given these conditions, the goal of this study is to propose a Tier 3 level methodology to calculate $CO_2$ and $NO_X$ emissions on inter-regional roads using the information from ITS infrastructure. The methodology may avoid the under-estimation issue caused by the concavity of emission factor curves because the ITS speed or volume information is aggregated by a short time interval. The proposed methodology was applied to 4 road segments as a case study. The results show that the management of heavy vehicles' speed is important to control the $CO_2$ and $NO_X$ emissions on road networks.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.10 no.5
• /
• pp.105-112
• /
• 2011

Delay reduction of vehicles at the intersection is highly dependent on the signal operation method. Improper traffic operation causes the violation of the traffic regulations and increasing traffic congestion. Delay because of congestion has contributed to the increase in carbon dioxide in the atmosphere. The focus of this paper is to measure the amount of carbon dioxide when the intersection is changed to roundabout. Even though, Intergovernmental Panel on Climate Change(IPCC) recommends Tier 1 method to measure the amount of greenhouse gas from vehicles, this paper used Tier 3 method because we could use the data of average running distance per each vehicle model. Two signalized intersections were selected as the study area and the delay reductions of roundabout operation were estimated by VISSIM microscopic simulation tool. The control delay for boksu intersection reduced from 28.6 seconds to 4.4 seconds and the KRIBB intersection sharply reduced from 156.4 seconds to 23.6 seconds. In addition, carbon dioxide for two intersections reduced to 646.5 ton/year if the intersection is changed to roundabout. Future research tasks include testing the experiment for networks, as well as for various intersection types.

• Journal of Climate Change Research
• /
• v.6 no.3
• /
• pp.175-184
• /
• 2015

In this study GC and PAS were used to calculate $N_2O$ concentration of exhaust gas from Wood Chip combustion system. Fuel supplied to the incinerator was collected and analyzed and then the analysis result was used to calculate $N_2O$ emissions. Tier 3 and Tier 4 Method were used to calculate the $N_2O$ emissions. Plant's Specific emission factor of $N_2O$ by Tier 3 Method was 0.35 kg/TJ, while default emission factor of Wood?Wood Waste proposed by 2006 IPCC G/L was 4 kg/TJ. So the $N_2O$ emission factor of this study was 3.65 kg/TJ lower compared to the IPCC G/L. The total emissions calculated by Plant's specific emission factor was 4.22 kg during the measuring period, but by Tier 4 Method it was 7.88 kg. This difference in emissions was caused by the difference of continuous measuring and intermittent sampling. It would be necessary to apply continuous measuring to calculate emissions of $Non-CO_2$ gas whose the density distribution is relatively high. However currently, according to the target management guideline of greenhouse gas and energy, the continuous measuring method to calculate greenhouse gas emission is applied only to $CO_2$. Therefore for reliable greenhouse gas emission calculation it would be necessary to apply continuous measuring to calculate $Non-CO_2$ gas emission.

• Journal of the Korean Applied Science and Technology
• /
• v.33 no.4
• /
• pp.855-863
• /
• 2016

Most greenhouse gases were arisen from the generation and use of energy, more than about 95 % of greenhouse gas from the traffic section was resulted by the transportation fuels. Also, when using the $CO_2$ emission factor suggested at IPCC G/L, there was the weakness which did not reflect the own property of fuel by country. And most industrialized countries have applied with the $CO_2$ emission factor of Tier 2 or Tier 3 to make the national greenhouse report to submit to UN according to the Kyoto Protocol. In this study, the transportation fuels using in domestic like unleaded gasoline, diesel, etc were analysed to identify the physical/chemical properties and these data were used to calculate the $CO_2$ emission factor of each fuels. And the study analysed the time series analysis to compare the property of fuels according to the change of time.

• Journal of Korean Society of Transportation
• /
• v.29 no.5
• /
• pp.55-65
• /
• 2011

In effort to estimate sustainability of the transportation sector, this study conducts a comparative analysis of methodology suggested for measuring greenhouse gas emission. There are two approaches proposed by the UN IPCC: 1) top-down approach (TDA) based on the amount oil sales, and 2) bottom-up approach (BUA) utilizing the velocity of moving source and traffic volume data. The subject areas for analysis were selected based on research results by the Korea Transportation Institute that evaluate traffic sustainability of each local government. Gwacheon-si being one of the top ranked areas in sustainability, and Anseong-si being ranked at the 7th level were analyzed. By the tier 1 methodology, Gwacheon-si and Anseong-si are estimated to create 74,813ton/yr, and 584,125ton/yr of the greenhouse gas emission, respectively. The tier 3 methodology, however, estimates Gwacheon-si and Anseong-si to create 91,462ton/yr, and 163,801ton/yr of the emission, respectively. Comparison of the two estimated emissions shows considerable differences; i.e., the tier 3 method over estimates Gwacheon-si's emission by 22.3% whereas it underestimates Anseong-si's greenhouse gas emission by the factor of about 3.5 compared to the emissions obtained from the tier 1 method. The result from this study implies that the traffic-sustainability-index based grade of each local government can be evaluated differently by the method adopted for measuring greenhouse gas emission.

• 한국신재생에너지학회:학술대회논문집
• /
• 2011.05a
• /
• pp.189.1-189.1
• /
• 2011

Global warming effect was intensified due to rapid growth of fossil fuel consumption caused by urbanization and industrialization. Various efforts was being done to solve the problems leading to anomaly climate such as flood, downpour, heavy snow. As a results of international efforts for management of global warming, Kyoto Protocol, which was passed in Kyoto, Japan in 1997, designated $CO_2$, $CH_4$, $N_2O$, HFCs, PFCs, $SF_6$ as a global warming gases. And IPCC(Intergovernmental Panel on Climate Change) suggested IPCC guideline for systematic establishment of national greenhouse gas inventory. Among five categories in IPCC guideline, the representative emission source of waste category is SWDS(solid waste disposal site). The concentrative research should progress for effective management of greenhouse gas related with waste. In this study, Tier1 and Tier2 methods which was suggested by 2006 IPCC(Intergovernmental Panel on Climate Change) guideline, was used to predict methane generation from C sanitary landfill located in Chungju area. To predict methane generation from C sanitary landfill, all factors were defaults values that were provided by 2006 IPCC guideline and Korea emission factors for Tier1 and Tier2 method. And economics of generated methane was estimated. From the predicted result using IPCC guideline, the methane generation was persistingly increased over a 9-year period(2000 ~ 2008). Aggregated amount of methane generation was about 3,017ton and 3,170ton predicted by Tier1 and Tier2, respectively. From the results of estimated economic value gained by generated methane from the C sanitary landfill for ten years from now(2010 ~ 2020), the profit was about 2.39 ~ 2.76 hundred million won.

• ETRI Journal
• /
• v.40 no.6
• /
• pp.726-735
• /
• 2018

Femtocells are good examples of the ultimate networking technology, offering enhanced indoor coverage and higher data rate. However, the dense deployment of femto base stations (FBSs) and the exploitation of subcarrier reuse between macrocell base stations and FBSs result in significant co-tier and cross-tier interference, thus degrading system performance. Therefore, appropriate resource allocations are required to mitigate the interference. This paper proposes a discrete bacterial foraging optimization (DBFO) algorithm to find the optimal resource allocation in two-tier networks. The simulation results showed that DBFO outperforms the random-resource allocation and discrete particle swarm optimization (DPSO) considering the small number of steps taken by particles and bacteria.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.58 no.3
• /
• pp.214-222
• /
• 2022

This study calculated the on-site measurement (Tier 4) of greenhouse gases emitted during the production stage of major fishing periods that utilize set nets and bamboo weir fishing boats. In addition, using theoretically calculated results (Tier 1), the emission factor presented by the Intergovernmental Panel on Climate Change (IPCC) was comparatively analyzed. On average, carbon emissions for each operating period in the bamboo weir and set net were calculated to be 0.16 and 3.58 kg CO₂ time^-1, respectively; and the measurement values (Tier 4) for each tool were about 4-17 times lower than their respective theoretical values (Tier 1). Significant differences were found based on engine performance. As port entry, port departure, and operating periods of the vessels show negligible variation with short distances, the operation of the vessel engine was considered as the main variable for carbon emissions in anchovy set net fishing.

• Journal of Korean Society of Transportation
• /
• v.32 no.6
• /
• pp.694-702
• /
• 2014

Since Greenhouse Gas Inventory & Research Center (GIR) of Korea was founded in 2010, the annual greenhouse gas inventory reports, one of the collections of GIR's major affairs, have been published from 2012. In the reports many items related to greenhouse gas emission quantities are included, but among them uncertainty values are replaced to basic values which IPCC guideline suggests. Even though IPCC guideline suggests the equations of each Tier level in details, the guideline recommends developing nation's own methodology on uncertainty which is closely related to statistical problems such as the estimation of a probability density function or Monte carlo methods. In the road transportation sector the emissions have been calculated by Tier 1 but the uncertainties have not been reported. This study introduce a bootstrap technique and Monte carlo method to estimates annual emission quantity and uncertainty, given activity data and emission factors such as annual traveled distances, fuel efficiencies and emission coefficients.

• Journal of the Korean Society for Railway
• /
• v.15 no.4
• /
• pp.408-412
• /
• 2012

Recently, new climate change mechanism after 2020 year has been accepted with the parties, and so government is pushing ahead the GHG reduction policies to achieve the effective results. Especially, it is essential to enhance the role of railroad in the public traffic system as well as to develop new cars with high energy efficiency for the GHG reduction of transportation sector. Thus, the calculation method of GHG emission of railroad should be established to manage the emission continuously. In this study, the calculation method of GHG emission of railroad was defined with Tier level considering its emission sources to refer to 2006 IPCC guideline for national GHG inventories. Also, the GHG emission of railroad at Tier 1 level was investigated using the activity data related to the amount of diesel and electricity consumption from 2008 to 2010. As a result, total GHG emission in 2010 was about 2,060 thousands ton CO2e, which have 73% of electricity and 27% of diesel. In future, the plans on the GHG reduction of railroad will be accomplished by the analysis of the detailed trends on the basis of the emission management of Tier 3 level under operating patterns. Therefore, it is important to develop the specific GHG emission factors of railroad in advance.