• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.44 no.5
• /
• pp.595-602
• /
• 2024

This paper analyzes serviceability guidelines and index related to the motion of floating structures concerning human comfort. The guidelines for the motion of floating structures regarding human comfort must meet requirements such as including frequency range of floating structure and providing index for vertical direction, which is a major component of human discomfort. Therefore, ISO 2631-1:1997 was found to be applicable. The evaluation of serviceability of the floating structure showed that the frequency-weighted RMS acceleration, due to the characteristics of frequency weighting function, is significantly influenced by the period of the floating structure. Additionally, the frequency-weighted RMS acceleration presented lower values compared to the general RMS acceleration. These results are expected to contribute to the establishment of reasonable guidelines for human activities to the motion of floating structures.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.44 no.5
• /
• pp.663-672
• /
• 2024

Nitrate contamination primarily results from agricultural activities and wastewater inputs, potentially leading to groundwater pollution. This study analyzed the reactive transport of nitrate in surface-groundwater interactions in the Gadeok-myeon, Cheongwon-gun, using integrated SWAT, MODFLOW, and RT3D models. The study used SWAT to simulate hydrological cycles, MODFLOW for groundwater flow analysis, and RT3D to model the reactive transport of nitrate. SWAT was used to estimate daily groundwater recharge and nitrate concentrations, which were then input into MODFLOW and RT3D models. The results showed that groundwater flow and reactive transport of nitrate were effectively simulated, providing insights into improving predictive models for groundwater and surface water interactions.

• 한국도로학회지:도로
• /
• v.5 no.4 s.18
• /
• pp.86-87
• /
• 2003

• Journal of the Korean Geotechnical Society
• /
• v.33 no.12
• /
• pp.115-125
• /
• 2017

PHC-W earth retaining wall could be constructed continuously. Various retaining wall methods such as C.I.P. etc. method require separate waterproof method. However, the PHC-W retaining wall method prevents leakage of groundwater by inserting a waterproofing material at connection part between 2 PHC piles. In this study, the experimental study on 3 waterproofing method for PHC-W retaining wall was conducted at the model pressure chamber. In the method using textile with 1-liquid type and 2-liquid type urethane, rapid leak occurred at the pressure of 120 kPa and 140 kPa or more. In the method of textile with grouting, rapid leak occurred at the pressure of 120 kPa or more, however, in this method, the rapid leakage happened at the top part and the bottom part reinforced with urethane.

• Journal of the Korean Geophysical Society
• /
• v.10 no.1
• /
• pp.37-44
• /
• 2007

Nowadays, Global Navigation Satellite System(GNSS) which is the new concept of positioning system has been developed because of satisfaction human's intelligent desire and rapid science development. GNSS which is represented by GPS provides 3-Dimension positioning information not expensively in whenever, wherever. The industry of positioning information has extending civil market widely as well as military market. So GNSS is running the role of society infra structure including car and airborne navigation, civil engineering, GIS resource, telematics and LBS, and so on. As USA removes the SA(Selective Availability), GPS has monopolizing the market and other countries have been depended on GPS, absolutely. In this paper, the author developed the software for analysis of influence using next generation, Galileo system. The local analysis was performed according to positioning mode. And GPS/Galileo combined system can implement positioning in the worst mask environment like urban cannon.

• The Korean Journal of Archival Studies
• /
• no.77
• /
• pp.75-107
• /
• 2023

In recent discussions on civil records, the term citizen records is being used instead of civil records. It is necessary to analyze the implications of using the term 'citizen record' instead of the term 'civil record'. Specifically, this paper examines how various words, including min, are understood and used in modern Korean politics and society, and the conceptual changes in relation to social changes in Korean society, so that we can name them civil records rather than civilian records. We want to find out the conceptual implications of what we do. To this end, first, we understand the concept of citizen as a historical contrast to the people, and second, we examine the meaning of citizen record management as part of citizenship. Furthermore, from the perspective of associational civic movements, we will look at village development and community movements, and consider the political and social meanings of civic records produced by citizens in their daily lives through these activities.

• Journal of the Korean Society of Safety
• /
• v.20 no.2 s.70
• /
• pp.113-118
• /
• 2005

Recently, the corrosion of reinforced concrete structures has received great attention related with the deterioration of sea-side structures, such as new airport, bridges, and nuclear power plants. In this regards, many studies have been done on the chloride attack in concrete structures. The purpose of the present study is to explore the influences of chloride attack parameters to service life of reinforced concrete structures and to propose the rational program for the guarantee of service life. for this purpose, several codes for durability design have been examined and the diffusion analysis based on Fick's second law has been performed with various parameter value. The present study indicates that durability design code of Japan Society of Civil Engineers is more rational than other codes but the application of durability design code of JSCE to domestic durability design needs more studies to the various parameter values related with chloride penetration.

• Journal of Contemporary Eastern Asia
• /
• v.13 no.2
• /
• pp.15-39
• /
• 2014

This research conducted a before/after naturalistic field experiment, with the early Arab Spring as the treatment. Compared to before the early Arab Spring, after the observation period the associations became stronger among the Web terms: 'Jihad, Sharia, innovation, democracy and civil society.' The Western concept of civil society transformed into a central Islamist ideological component. At another level, the inter-nation network based on Jihad-weighted Web hyperlinks between pairs of 46 Muslim Majority (MM) nations found Iran in one of the top two positions of flow betweenness centrality, a measure of network power, both before and after early Arab Spring. In contrast, Somalia, UAE, Egypt, Libya, and Sudan increased most in network flow betweenness centrality. The MM 'Jihad'-centric word co-occurrence network more than tripled in size, and the semantic structure more became entropic. This media "cloud" perhaps billowed as Islamist groups changed their material-level relationships and the corresponding media representations of Jihad among them changed after early Arab Spring. Future research could investigate various rival explanations for this naturalistic field experiment's findings.

• Journal of Korean Society of Water and Wastewater
• /
• v.32 no.5
• /
• pp.381-388
• /
• 2018

Microbubbles oxygen transfer to water was simulated based on experimental results obtained from the bubbles generation operated under varying liquid supply velocity to the multi-step orifices of the generator. It had been known that liquid supply velocity and bubble size are inversely related. In the oxygen transfer, a non-steady state was assumed and the pseudo stagnation caused the slow movement of bubbles from the bottom to the water surface. Two parameters were considered for the simulation: They represent a factor to correct the pseudo stagnation state and a scale which represented the amount of bubbles in supply versus time. The sum of absolute error determined by fitting regression to the experimental results was comparable to that of the American Society of Civil Engineers (ASCE) model, which is based on concentration differential as the driving force. Hence, considering the bubbles formation factors, the simulation process has the potential to be easily used for applications by introducing two parameters in the assumptions. Compared with the ASCE model, the simulation method reproduced the experimental results well by detailed conditions.

• Journal of applied mathematics & informatics
• /
• v.30 no.3_4
• /
• pp.613-622
• /
• 2012

In this paper, we propose a new algorithm to modify the standard Mann' process to have strong convergence for $k$-strictly pseudo-contractive non-self mapping in Hilbert spaces.