• Journal of Climate Change Research
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• v.1 no.1
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• pp.13-20
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• 2010

Recently, the operation of construction equipments have increased by many construction project. So a respectable amount of greenhouse gas is expected from construction equipments. But the greenhouse gas emissions from construction equipment have been high uncertainty due investigation of a lack of activity data and emission factors in Korea. In this study, annual greenhouse gas emissions from construction equipment are estimated by IPCC's Tier 2 and Tier 3 method. These methods require emission factors, fuel consumption, average kilowatts and operating hours. As the results, the nationwide emission from construction equipments by Tier 2 and Tier 3 are calculated as $21,784kton-CO_2eq/year$ and $22,811kton-CO_2eq/year$ in 2008.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.3D
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• pp.375-381
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• 2011

This study presents an analysis of $CO_2$ emission reduction effect on bus information system (BIS) which is operated to improve various services of bus transit such as rapid and on-time service. Although the Intergovernmental Panel on Climate Change (IPCC) released three methodological types of models for analyzing the amount of greenhouse gas reduction, this study used the Tier 3 method that is the most concrete one. A case study was performed to a 8.3 km section of Daejun-Chungjoo BIS system, and dataset required to the Tier 3 method was obtained from ITS-based surveillance systems. The study result showed that the reduction effect of $CO_2$ on BIS operation was yearly $39.45tCO_2/km$. Therefore, such effect can be potentially useful to a measurement of effectiveness (MOE) of BIS projects hereafter.

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

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2000.04a
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• pp.164-166
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• 2000

어플리케이션이 조직 전체로 대형화되고, 대규모의 분산 시스템이 적용됨에 따라 예상치 못한 새로운 문제에 직면하게 되는데, 분산환경에 있어서 어플리케이션의 관리, 보안 관리, 어플리케이션의 부하 증대로 인한 성능 저하, 이기종 DBMS간의 연계 문제 등이 그 것이다. 이러한 문제 해결 방법의 하나로 3계층(3-Tier) 아키텍처를 들 수 있는데, 초기 시스템 투자 비용이 2-Tier에 비해 많이 들고 구현이 상대적으로 어려움에도 불구하고 이기종 DBMS 연결, 다양한 하드웨어 및 개발툴을 선택할 수 있는 유연성, 전사 규모로의 확장성, 동시 병행 개발과 소프트웨어 재활용을 통한 개발 생산성 향상 측면에서의 장점을 제공한다. 본 연구에서는 부서 단위의 관리시스템을 개발하기 위해 초기 2-Tier 개념의 클라이언트/서버 시스템 컨셉에서 출발한 뒤, 사업부 차원의 상위 시스템 아키텍처가 이기종 자원(하드웨어, DBMS, 개발 툴 등)을 통합해 주는 패러다임인 3-Tier로 변경됨에 따라 발생하게된 관련 시스템과의 인터페이스 및 개발 구축 방법론에 대한 사례를 소개한다.

• Journal of the Korea Society for Simulation
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• v.18 no.4
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• pp.29-37
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• 2009

This paper deals with the priority queues exploited for the management of future event list in discrete event simulation. Among several implementations of priority queues, MList which consists of 3 tiers has been known to reveal the good performance. To improve the performance of MList, Dynamic-Shift MList (DSMList) is proposed in this paper. Whenever the number of events in tier 3 exceeds a critical number, DSMList creates new calendar queue in tier 2, then moves events from Tier 3 to the calendar queue. Instead of one calendar queue, therefore, a number of calendar queues are dynamically created in tier 2. Throughout experiments for the performance evaluation of DSMList, it shows that at least 20% improvement is obtained compared with MList.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.10
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• pp.701-708
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• 2011

In this study, the emissions of GHG from general ships were calculated by Tier1 method based on the fuel consumption, and by Tier3 method based on the activities data such as power and SFOC of each engine, sailing characteristics (e.g. time and load factor, etc.) considering the ship type. In 2009, the emissions of GHG by Tier1 and Tier3 method were appeared 28.27 mega-ton $CO_{2eq}$ and 30.81 mega-ton $CO_{2eq}$. The emissions by Tier3 were slightly more than those by Tier1. We found that the values of the sailing characteristics for surveyed data are overestimated slightly. In the near future, more detailed researches for sailing characteristics considering ship types would be needed for sailing, anchoring, and berthing condition, etc.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.4
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• pp.405-415
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• 2011

The objective of this study was to compare greenhouse gas emissions from road transportation by calculation methods (Tier 1, Teir 2, and Tier 3). Tier 1 based on 2006 IPCC guidelines default emission factor and amount of fuel consumption. The Tier 2 approach is the same as Tier 1 except that country-specific carbon contents of the fuel sold in road transport are used. Tier 2 based on emission factor of guidelines for local government greenhouse gas inventories (Korea Environment Corporation), the fuel consumption per one vehicle, and the registered motor vehicles. The Tier 3 approach requires detailed, country-specific data to generate activity-based emission factors for vehicle subcategories (National Institute of Environmental Research) and may involve national models. Tier 3 calculates emissions by multiplying emission factors by vehicle activity levels (e.g., VKT) for each vehicle subcategory and possible road type. VKT was estimated by using GIS road map and traffic volume of the section. The GHG average emission rate by the Tier 1 was 728,857 $tonCO_2eq$/yr, while Tier 2 and Tier 3 were 864,757 $tonCO_2eq$/yr and 661,710 $tonCO_2eq$/yr, respectively. Tier 3 was underestimated by 10.1 and 20.7 percent for the GHG emission observed by Tier 1 and Tier 2, respectively. Based on this study, we conclude that Tier 2 is reasonable GHG emissions than Tier 1 or Tier 3. But, further study is still needed to accurate GHG emission from Tier 3 method by expanding the traffic survey area and developing the model of local road traffic.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2010.04a
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• pp.209-210
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• 2010

• Journal of Climate Change Research
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• v.5 no.1
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• pp.61-70
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• 2014

The amount of greenhouse gas (GHG) emissions has been increasing steadily over the last 3 years (2009~2011), averaging 5.7 percent a year, due to the growth of low cost carriers and the increased demand for air transportations. The present study attempts to investigate the aviation fuel consumption and GHG emissions of Tier 3a type by the flight phase from three aircraft type such as B737-600(routes between Gimpo-Jeju airport), B737-700(routes between Gimpo-Jeju airport and Inchon-Narita), B737-800(routes between Inchon-Narita) using the Flight Operation Quality Assurance(FOQA) data of the year 2011.

• Journal of Climate Change Research
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• v.1 no.1
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• pp.51-57
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• 2010

Recently the number of motorcycles has increased in urban area, and it is believed that motorcycle is one of the air pollution and greenhouse gas emission sources. But the greenhouse gas emission from motorcycle has been high uncertainty due investigation of a lack of activity data and emission factors in Korea. So in this study, the greenhouse gas emission from motorcycle is estimated by considering the population of moped and VKT(vehicle kilometers travelled) of motorcycle by recent other studies. And the emissions by IPCC Tier 2 and Tier 3 methodology are calculated and compared. As the results, the nationwide $CO_2$ equivalent emissions from motorcycles by Tier 2 and Tier 3 method are calculated as 2,758 kton/yr and 2,739 kton/yr in 2008. The contribution ratio of this emission is estimated as 2.7% in on-road transport sector.