• Journal of Wetlands Research
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• v.18 no.1
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• pp.94-99
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• 2016

Non-point source control has been issued and intensively studied for the control of water quality in streams and rivers. In this study, non-point source pollutants monitoring was conducted at the end of five small streams which were connected to a main stream in three stages including Phase I (one hr before the rainfall), Phase II (one hr after the rainfall), and Phase III (six hrs after the rainfall). For all five small streams, the concentrations and loading rates of non-point source pollutants significantly increased due to the rainfall. As a result of this, priority control streams and priority pollutants were suggested to prepare for future plans of the non-point source control.

• Journal of Korean Society of Transportation
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• v.32 no.4
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• pp.410-420
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• 2014

This research suggests a new tram signal priority model which determines signal timings and tram intersection waiting time using analytical method. This model can calculate the signal timings for Early Green and Green Extension among the active tram signal priority techniques by tram detection time of upstream detector. Moreover, it can determine the tram intersection waiting time that means tram intersection travel time delay from a vantage point of tram travel. Under the active tram signal priority condition, priority phases can bring additional green time from variable green time of non-priority phases. In this study, the signal timing and tram intersection waiting time calculation model was set up using analytical methods. In case studies using an isolated intersection, this study checks tram intersection waiting time ranged 12.7 to 29.4 seconds when variable green times of non-priority phases are 44 to 10 seconds under 120 seconds of cycle length.

• Journal of KIISE:Information Networking
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• v.27 no.1
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• pp.22-29
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• 2000

In this paper, we analyzed the performance of EY-NPMA(Elimination Yield-Non-preemptive Priority Multiple Access) protocol-channel access control protocol of HIPERLAN(HIgh PErformance Radio Local Area Network) type 1 specification, adopted as european high speed wireless LAN standard by ETSI(European Telecommunication Standards Institute). We established a system model for EY-NPMA protocol analysis, analyzed success probability in a channel access cycle, and derived expressions for the average length of contention phase. Using a M/G/1 model, we approximated the normalized delay, and throughput, and we evaluated these results by simulations.

• Journal of Korean Society of Transportation
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• v.31 no.5
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• pp.60-70
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• 2013

This study aims to develop a truck priority on left-turn algorithm that can reduce greenhouse gas emissions by reducing heavy duty truck's stops at signalized intersection. The signal priority is granted for a left-turn phase, because heavy duty trucks can deteriorate left-turn traffic flow due to the low acceleration or deceleration rate and large turn radius. Truck priority allows to provide the stable speed control for heavy duty truck, and reduces emissions at the signal intersection. Also, two signal recovery strategies are compared for various traffic conditions. This study analyzes the effectiveness of truck priority such as greenhouse gas emissions and fuel consumption reduction, and total travel time saving using the PARAMICS and Comprehensive Modal Emissions Model (CMEM). The results show that signal priority for heavy duty trucks has an effect on reducing greenhouse gas emissions and fuel consumptions at non-peak hour. Also, it shows decreasing total travel time due to reducing truck stops.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.12
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• pp.1099-1104
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• 2007

In order to develop non-heated STAl(super thermal resistant Aluminum alloy) for ampacity gain conductor, the systematic research was carried out. Especailly, the effect of a very small amount of Zr, Sc element in EC grade Al ingot on mechanical and electrical properties was our priority. As a result, it was found that the strength and recrystallization temperature of designed alloy was gradually increased with Zr, Sc addition up to 0.3 wt.%. However, the electric conductivity showed no drastic change. The tensile strength and recrystalliztion temperature, $17.75{\sim}20.05\;kgf/mm^2$ and $420{\sim}520\;^{\circ}C$, was obtained at 0.3 wt.% Zr, Sc addition, respectively. Particles of the $Al_3Zr$ and $Al_3Sc$ phase affected the ambient and elevated-temperature strength of the alloys.

• Journal of Environmental Science International
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• v.16 no.3
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• pp.247-253
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• 2007

Polycyclic aromatic hydrocarbons (PAHs) are a major concern because of their potential mutagenic and carcinogenic risks to human beings. One of these harmful, yet commonly observed PAHs is pyrene. Pyrene is one of the 16 PAHs listed by the United States Environmental Protection Agency as priority pollutants. The purposes of this research are to develop a method of pretreatment for PAH contaminants prior to a typical biological treatment and to demonstrate the biodegradablity of these compounds. Since pyrene is non-polar, hexane was chosen as a solvent to effectively dissolve pyrene. Pyrene solutions were treated with ozone, as it has hish oxidation capacity and electrophilic character. The intermediates and byproducts of pyrene were dissolved in alkaline water at pH 11.4 and neutralized to test for $BOD_5$, COD, and toxicity. These solutions were further ozonated and assessed of biodegradability. The first-order rate constant to was found to be between $0.121day^{-1}$ and $0.081 day^{-1}$, depending on the duration of reozonation. The $BOD_5/COD$ ratio was found to 0.66. The toxicity test showed that after 10 min of reozonation time, the byproducts and intermediates of pyrene were within the lion-toxic range of ${\pm}10%$ inhibition for E-Coli bacteria.

• Journal of the Korea Society of Computer and Information
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• v.8 no.2
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• pp.97-105
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• 2003

This thesis proposes a new type of Input-Output Buffered ATM Switch which employs an arbiter and its performance under different traffic conditions studied. The proposed switch is designed with a view to exploit the architecture and other characteristics of the arbiter The primary aim of the proposed switch is the elimination, or at least, the reduction of HOL blocking phenomenon which occurs in the simple input buffered switch. Several HOL arbitration algorithms have been proposed for this purpose in the literature. The Proposed switch attempts to reduce the HOL blocking as it uses the arbiter and the buffer at the output Port in an effective manner. The arbiter is designed to work with Three Phase Algorithm which is one of the many well known HOL arbitration algorithms . The proposed switch acquires control over priority transmission through the REd signal. As the signals are transmitted to the arbiter, the latter controls the one which is sent by the input buffer. Computer simulation results have been provided to demonstrate the effectiveness of the proposed switch under non-uniform random traffic conditions.

• Journal of Korean Society on Water Environment
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• v.22 no.6
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• pp.1123-1129
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• 2006

Pyrene of natural and anthropogenic sources is one of the toxic, mutagenic polycyclic aromatic hydrocarbons (PAHs) listed as priority pollutants. The objectives of this research are to break down pyrene by using ozonation, identify the intermediates and byproducts of pyrene, and test the biodegradability of intermediates and byproducts of pyrene in the aqueous phase. Since pyrene is non-polar, hexane was chosen as a solvent to effectively dissolve pyrene. Pyrene solutions were treated with ozone, as it has high oxidation capacity and electrophilic characteristic. After different ozonation pretreatment times (2, 3, and 10 minutes), intermediates of pyrene in the form of yellowish solid were collected from the hexane solution using a centrifuge. They were identified by gas chromatography/mass spectrometer (GC/MS). $BOD_5$, COD, and E-coli toxicity tests have been performed to assess the ozonation products.

• The Journal of the Korea Contents Association
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• v.13 no.10
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• pp.480-494
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• 2013

Globally branded culture festival in the region as a key component to the originality and distinction and with local residents and visitors to share experience and has succeeded in branding through Mind. Than mimics festivals in competitive and differentiated cultures containing festivals create a unique festival brand, and through the cultural and economic competitiveness, as well as the phase of the World Festival and preserve local culture and identity. Developing The best areas will be an asset. In order to build this world-class festival brand differentiation strategy above all, must be a top priority, Discrimination discovery and development of the local culture and sensibility in the age of the most powerful marketing tool that is being presented through storytelling brand assets to be passed on to visitors should. Thus the creation of storytelling festivals. Sensitivity of the festival right direction and in an era of paradigm key drivers of the local economy, such as image enhancement, and building long-term regional development and differentiation based on quality of life by creating a local culture can improve will Region's cultural and economic areas, the most important resource for the success of the festival is uniformly short-term planning and configuration, tube-driven operating as a one-sided non-participation. Sharing. Communication with an emphasis on the application of storytelling that is essential is considered.

• Journal of the Korean association of regional geographers
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• v.20 no.2
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• pp.176-188
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• 2014

Since the late 1990s, a nationwide movement against dam and river-mouth weir plans in Japan has been promoted with a movement against a river-mouth weir for the Nagara river(長良川). This movement has been a catalyst for institutional frameworks on the central government's dam and river-mouth weir plans. Subsequently, water resource and river management policies have entered a new phase, with provinces governors's participation in "Statements on withdrawal from dam and river-mouth weir" as well as the seizing of power by the Democratic Party. However, problems with dams and river-mouth weirs have been confused due to poor countermeasures from the Democratic Party and to the Liberal Democratic Party(LDP)'s return to power. The fundamental causes on this situation are the non-establishment of fiscal norms for public projects and the rigidity of the water-right allocation system in Jananese policy-making processes. To successfully settle future policy on water resources and rivers, the first priority is to prepare specific institutional frameworks on finance of public projects and to organize a practical policy coordination system among government organizations. These policy tasks provide implications for river and water management policy in Korea.