Experimental investigations on the characteristics of snow accretion using the EMU-320 model train

This paper presents a snow accretion test conducted in a climate wind tunnel to investigate the icing process on a model train. The model used within this experiment was the cleaned-up and 2/3-scaled version of EMU-320, which is a high-speed train in Korea. The model was designed without an electronic power source or heat source so that the wheels did not rotate and snow accretion on the model did not occur due to heat sources. To investigate snow accretion, four cases with different ambient temperatures were considered in the climate wind tunnel on Rail Tec Arsenal. Before analyzing the snow accretion on the train, the snow flux and liquid water content of snow were measured so that they could be used as the input conditions for the simulation and to ensure the analysis of the icing process was based on the characteristics of the snow. Both qualitative and quantitative data were obtained, whereby photographs was used for qualitative analysis, and the density of the snow sample and the thickness of snow accreted on the model were used for quantitative analysis. Based on the visual observations, it was deduced that as the ambient temperature increased, the range of the snow accreted was broader. The thickness of snow accreted on the model nose was the largest on the upper and lower part at -3 oC, and on the middle part at -5 oC. Additionally, the cross section of snow accreted was observed to be trench-like. Similar icing processes were observed to occur on the slope of nose. Snow accreted on all components of the bogie, and for all cases, the thickness of snow at wheel was the largest at an arc angle of 40 to 70 o. These detailed data of experimental conditions can be applied as an input to simulations to improve simulations of ice conditions. Thus, they can facilitate the development of appropriate anti-icing designs for trainsComment: 31 pages, 23 Figures, 8 Table

Ambient particulate matter (PM10) concentrations in major urban areas of Korea during 1996–2010

AbstractIn this study, ambient particulate matter pollution was investigated using monthly PM10 concentration data collected from seven major cities in Korea from 1996 to 2010. The highest mean value for the whole study period is seen from the capital city, Seoul (63.2±17.9μg m–3), while the lowest is from Ulsan (46.7±14.8μg m–3). The concentrations of PM10 in all cities exhibited seasonal variations with the peak values occurring consistently in spring (March or April). The PM10 data in each city consistently exhibited strong correlations (p<0.01) with gaseous pollutants (SO2, NO2, and CO), except for O3 (p>0.05). The analysis of long term trends of PM10 levels indicates a weak but consistent decline in concentrations in most cities with the relative average annual reductions of between 0.4 and 2.8% y–1

The Determinant of Internet Banking Usage Behavior in Korea: A Comparison of Two Theoretical Models

Internet banking is an information intensive business and becomes a major trend in the financial marketplace. It is important to understand what factors will impact the actual use of internet banking. Therefore, this paper is aimed at analyzing the determinants of internet banking usage behavior in Korea. This study compares two models that predict an individual’s intention: Theory of Reasoned Action(TRA) and Theory of Planned Behavior(TPB). The results show that internet banking users ’ attitude and their perceived behavioral control play a vital role in influencing the behavioral intention of internet banking. However, intention is not formed by users ’ subjective norm in both TRA and TPB. In addition, attitude, subjective norm, and perceived behavioral control is, in turn, influenced by attitudinal belief structures, normative belief structures, control belief structures, respectively. Both TRA and TPB predict behavioral intention to use the internet banking quite well, with TPB having a slight empirical advantage. 1

Design of an Enhanced Web Archiving System for Preserving Content Integrity with Blockchain

A Web archive system is a traditional subject for preserving web content for the future and the importance is getting more significant due to the explosive growth of web content. The reference model for an open archival information system (OAIS) has been advising guidance for a long-term archiving system and most organizations that archive web content follow this guidance. In addition, the web archive (WARC) ISO standard is for web content archiving. However, there is no way to secure content integrity, and it is hard to identify the original. Because of limitations, a web archive system has a weakness against the dispute of content integrity. In this paper, we proposed the blockchain linked (BCLinked) web archiving system, which uses blockchain technology and an extended WARC field to keep a web content integrity metadata into a blockchain. Furthermore, we designed the BCLinked web archiving system, and we confirmed the proposed system secures content integrity through the experiment

AGU hydrology days 2012

2012 annual AGU hydrology days was held at Colorado State University on March 21 - March 23, 2012.Includes bibliographical references.Climate change has affected water resources and environment all over the world and its impacts assessment and adaptation are very important issues that are significant in terms of science and policies. In view of water resources, estimation of discharge is essential to make basic data in watershed management and water environment like flood and drought. The change of discharge has affected both eco-system and human system. So that, using technical methods are necessary to develop nature restoration and disaster reduction. Therefore, this study applied to GCMs (General Circulation Models) using A1B scenario which reflects climate characteristics of Korea well and analyze out the future climate change discharge. The main result of these studies is compared and analyzed at Nakdong River basin about discharge by A1B scenario. The study period (2011~2100) was divided into three periods (F1:2011~2040, F2:2041~2070, F3:2071~2100) and compared with observed data for 1980~2009. This study presents technical methodology for assessing influence on water environment resources. Furthermore, the results of this study expect to be quantitative and reliable data in studying climate change throughout the application to other rivers. If water environment impact assessment and analysis of the future water balance including a forecast of water supply and demand take place based on the results of this study, the results will be sufficiently valuable both as researches on national measures to climate change and policy materials

Formation of crystalline TiO2-xNx and its photocatalytic activity

Amorphous precursors to nitrogen-doped TiO2 (NTP) and pure TiO2 (ATP) powders were synthesized by hydrolytic synthesis and sol-gel method (SGM), respectively. Corresponding crystalline phases were obtained by thermally induced transformation of these amorphorus powders. From FT-IR and XPS data, it was concluded that a complex containing titanium and ammonia was formed in the precipitate stage while calcination drove weakly adsorbed ammonium species off the surface, decomposed ammonia bound Oil surface Or precipitated powder and led to substitution of nitrogen atom into the lattice of TiO2 during the crystallization. The activation energies required for grain growth in amorphous TiO2-xNx and TiO2 samples were determined to be 1.6 and 1.7 kJ/mol, respectively. Those reqUircd for the phase transformation from amorphous to crystalline TiO2-N-x(x) and TiO2 were determined to be 129 and 142kJ/mol respectively. A relatively low temperature was required for the phase transformation in NTP sample than in ATP sample. The fabricated N-doped TiO2 photocatalyst absorbed the visible light showing two absorption edges; one in UV range due to titanium oxide as the main edge and the other due to nitrogen doping as a small shoulder. TiO2-xNx photocatalyst demonstrated its photoactivity for photocurrent generation and decomposition of 2-propanol (IPA) Under visible light irradiation (lambda >= 420nm). (c) 2006 Elsevier Inc. All rights reservedclose657

Surgical outcomes of acetabular fracture of elderly patients with superomedial dome impaction

Abstract This study aimed to investigate the outcomes of elderly acetabular fractures according to the reduction of impacted dome fragments. A retrospective cohort study was performed in two institutions. Fifty-four patients aged ≥ 60 years with acetabular fractures were enrolled. Data for dome impaction and postoperative reduction was collected. Patients were divided into the good reduction group (displacement ≤ 3 mm) and poor reduction group (displacement > 3 mm). Postoperative osteoarthritis (OA), Harris hip score (HHS), total hip arthroplasty conversion, good/poor outcomes were compared between the two groups. The good reduction group (N = 45) demonstrated a lower proportion of radiographic OA (18 vs. 77%, P = 0.001), higher HHS (82.1 vs. 68.6, P = 0.022), and higher proportion of good outcomes than the poor reduction group (N = 9) (89 vs. 22%, P < 0.001). In a subgroup analysis of the patients with dome impaction, the good reduction group had a higher proportion of good outcomes (80 vs. 20%, P = 0.031). On comparing within the good reduction group, dome impaction did not influence clinical outcomes. Elderly acetabular fractures demonstrated favorable outcomes when adequate reduction was achieved even with dome impaction. Well-reduced dome impaction could achieve satisfactory outcomes in elderly acetabular fractures