• 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.

• Speech Sciences
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• v.4 no.1
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• pp.113-133
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• 1998

The system proposed in this paper prosodically transcribes the intonation patterns, prosodic structures, phrasings, and other prosodic aspects of Korean utterances, on four parallel tiers: a tone tier, an orthographic tier, a break index tier, and a miscellaneous tier. The tone tier employs two phrase accents (L* and H *), three accentual phrase boundary tones (L-, H-, LH-), and four intonational phrase boundary tones (L%,H%,LH%,LHL%) in order to provide a phonological transcription of pitch events associated with accented syllables and phrase boundaries. The break index tier uses five break indices, numbered from 0 to 4, which mark a prosodic grouping of words and its prosodic structure in an utterance. Among the five indices, the break index 3 and the break index 4 align with an accentual phrase boundary tone and an intonational phrase boundary tone, respectively, in the tone tier.

• International Journal of Computer Science & Network Security
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• v.22 no.4
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• pp.329-339
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• 2022

Small cells, particularly femtocells, are regarded a promising solution for limited resources required to handle the increasing data demand. They usually boost wireless network capacity. While widespread usage of femtocells increases network gain, it also raises several challenges. Interference is one of such concerns. Interference management is also seen as a main obstacle in the adoption of two-tier networks. For example, placing femtocells in a traditional macrocell's geographic area. Interference comes in two forms: cross-tier and co-tier. There have been previous studies conducted on the topic of interference management. This study investigates the principle of categorization of interference management systems. Many methods exist in the literature to reduce or eliminate the impacts of co-tier, cross-tier, or a combination of the two forms of interference. Following are some of the ways provided to manage interference: FFR, Cognitive Femtocell and Cooperative Resource Scheduling, Beamforming Strategy, Transmission Power Control, and Clustering/Graph-Based. Approaches, which were proposed to solve the interference problem, had been presented for each category in this work.

• 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.

• Journal of Information Technology Applications and Management
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• v.22 no.1
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• pp.153-163
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• 2015

The purpose of this study is to investigate the relationship among factors that expand the win-win growth between domestic finished goods-making manufacturers and subcontractors. One-hundred twenty six firms participated for this study and were used for the data analysis. As a result of analysis, first, it was found that the win-win growth between first-tier suppliers and second-tier suppliers has positive effects on the win-win growth made by second-tier suppliers helping the third-tier suppliers. Second, it was found that the win-win growth policies supported by the government for the positive relationship between first-tier suppliers and second-tier suppliers for the finished goods-making manufacturers have positive effects on the win-win growth between second-tier suppliers and third-tier suppliers. Third, the results also showed that the win-win growth between second-tier suppliers and third-tier suppliers has a positive influence both on the financial and on the non-financial performances of the second-tier suppliers. Based on the results of this study, it is recommended to (1) construct infrastructure by sector through partnership between finished goods-making manufacturers and subcontractors, (2) draw in active support through the governmental win-win growth policies, (3) induce increasing productivities through information sharing, manpower support, technical support and educational support, and (4) strengthen and cultivate the culture of the small- and medium-sized companies.

• 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.

• Speech Sciences
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• v.2
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• pp.159-172
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• 1997

This paper proposes a prosodic representation system of the Kyungnam dialect of Korean, based on the ToBI system. In this system, diverse intonation patterns are transcribed on the four parallel tiers: a tone tier, a break index tier, an orthographic tier, and a miscellaneous tier. The tone tier employs pitch accents, phrase accents, and boundary tones marked with diacritics in order to represent various pitch events. The break index tier uses five break indices, numbered from 0 to 4, in order to represent degrees of connectiveness in speech by associating each inter-word position with a break index. In this, each break index represents a boundary of some kind of constituent. This system can contribute not only to a more detailed theory connecting prosody, syntax, and intonation, but also to current text-to-speech synthesis approaches, speech recognition, and other quantitative computational modellings.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.4
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• pp.454-465
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• 2012

The Korean government decided to reduce 30% of GHG (greenhouse gas) emissions BAU in 2020. Since many efforts to reduce emissions are urgently needed in Korea, the central administrative organization urges local governments to establish their own reduction schemes. Among many GHG emission categories, the emission from mobile source in Gyeonggi Province accounted for 25.3% of total emissions in 2007 and further the emission from road transport sector occupied the most dominant portion in this transportation category. The objective of this study was to compare 3 types of GHG emissions from road transport sector in 31 local cities/counties of Gyeonggi Province, which have been estimated by Tier 1, Tier 2, and Tier 3 methodologies. As results, the GHG emission rates by the Tier 1 and Tier 2 were $19,991kt-CO_2\;Eq/yr$ and $18,511kt-CO_2\;Eq/yr$, respectively. On the other hand, the emission rate by Tier 3 excluding a branch road emission portion was $18,051kt-CO_2\;Eq/yr$. In addition, the total emission rate including all the main and branch road portions in Gyeonggi Province was $24,152kt-CO_2\;Eq/yr$, which was estimated by a new Tier 3 methodology. Based on this study, we could conclude that Tier 3 is a reasonable methodology than Tier 1 or Tier 2. However, more accurate and less uncertain methodology must be developed by expanding traffic survey areas and adopting a suitable model for traffic volumes.

• Journal of Climate Change Research
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• v.4 no.3
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• pp.235-244
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• 2013

Carbon dioxide emission estimation methods consist of four tiers according to the IPCC guideline. In this study, estimated results by tier 3 and tier 4 were compared with the theoretically calculated $CO_2$ emissions based on the mass balance approach for a gas fired power plant between March and May 2011. It was found that the relative differences were upto 17% between the measured emissions by tier 4 and theoretically estimated emissions, while the results of tier 3 were similar to those from theoretically estimated ones. The comparisons suggested the possibility of misestimation due to replacing missing, abnormal, or invalid data in continuous emissions monitoring system. When using only the data without those missing, abnormal, or invalid data, the relative differences decreased somewhat but still showed consistent differences depending on the stack. It is suggested that this differences might be due to the accuracy of the measurement instruments for the tier 4, especially, for the flow rate measurement instrument.

• Journal of the Korea Convergence Society
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• v.5 no.4
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• pp.9-13
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• 2014

The environment of IT is, currently, on its developing process to the period of cloud computing, big data, and business intelligence which not only enable computer and internet to be utilized like the water or the air, but also be a new motivating force for its advance. In the respect of various interactions and Infographics, however, it is requiring more demands from its users, and additional functions which cannot be provided by the Web Browser. In this study, therefore, it will be suggested a design of N-screen convergence presentation tier by using infographics based on N-Tier platform.