• Journal of the Korean Geotechnical Society
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• v.22 no.9
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• pp.61-68
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• 2006

Recently the large scale civil engineering projects are being implemented by reclaiming the sea or utilizing seashore and river embankment areas. The reclaimed land and utilized seashore are mostly soft ground that doesn't have sufficient bearing capacity. This soft ground consists of fine-grained soil such as clayey and silty soils or large void soil like peat or loose sand. It has high ground water table and it may cause the failure and crock of building foundation by uplift pressure and ground water leakage. In this study, the permittivity and the transmissivity were evaluated with the applied normal pressure in the laboratory. The laboratory model tests were conducted by utilizing geocomposite drainage system for draining the water out to release the uplift pressure. The soil used in the laboratory drainage test was dredged soil from the reclaimed land where uplift pressure problems can arise in soil condition. Geocomposite drainage system was installed at the bottom of apparatus and dredged soil was layered with compaction. Subsequently the water pressure was supplied from the top of specimen and the quantities of drainage and the pore water pressure were measured at each step water pressure. The results of laboratory measurements were compared with theoretical values. For the evaluation of propriety of laboratory drainage test, 2-D finite elements analysis that can analyze the distribution and the transferring of pore water pressure was conducted and compared with laboratory test results.

• Korean Journal of School Psychology
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• v.16 no.2
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• pp.89-110
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• 2019

This study is to verify relative influence of individual, parent, peer, teacher-related variables as protective factors and risk factors of academic hatred. Surveys were conducted with 1,015 (women, 57.3%) high school third grade students across eight schools where are located in Seoul, Incheon, and Geyonggi province. Correlation analysis and hierarchical multiple regression analysis were performed. The findings are summarized as follows. Teacher's academic pressure did not have significant correlation with student's basic psychological needs, teacher's autonomy support, teacher's support, and peer support whereas other variables showed significant correlation each others. The hierarchical multiple regression analysis indicated that student's individual competence and autonomy, parent's academic support, and teacher's emotional support work as protective factors and that parent's academic pressure functions as a risk factor. The effects of peer support disappeared when teacher-related factors were included. In addition, the effects of teacher's autonomy support disappeared, while the effects of teacher's support strengthened when learner's basic psychological needs were input. This study is meaningful in that it clarified academic hatred which had not been studied in other research and that it provided theoretical foundation for subsequent studies on academic hatred by examining relative influence of related variables. Lastly, it presented its limitation, implications on intervening strategies in school counseling, and suggestions for later studies.

• Korean Journal of Culture and Social Issue
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• v.14 no.2
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• pp.63-81
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• 2008

Hasteful behavior means choosing the best suited methods while behaving fast and quickly. We can't conclude whether hasteful behavior is totally bad or good. Striving for achievement of own certain purpose reflects achievement motivation or need for achievement. However, this striving also has potentiality of missing confirmation, therefore the potentiality may cause errors. The aim of this study is to investigate the psychological structure and characteristic of the hasteful behavior. One hundred ninety-one students conducted Hasteful Behavior Questionnaire, Achievement Motivation Measuring Scale, and NEO Personality Inventory. We analyzed data of 188 respondents, because of missing value. The result of factor analysis showed that hasteful behavior consisted of 5 factors- 「Uncomfortableness」, 「Time Pressure」, 「Isolation」, 「Boring Condition」, and 「Expecting Rewards」. According to correlations among the hasteful behavior factors and the relationship between hasteful behavior and achievement motivation, we found that hasteful behavior had two aspects, one was "Missing Confirmation(MC)" and the other was "Need for Achievement(NA)". We also found that 「Time Pressure」 was related to the both aspects. MC had a positive relation to Neuroticism, whereas MC correlated negatively with Conscientiousness. On the other hand, NA had a positive relationship with Extraversion and Achievement Striving.

• Journal of Wetlands Research
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• v.20 no.2
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• pp.181-189
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• 2018

This study was performed to analyze the dynamics and distributional condition of biological community and to support the basic information about the estuarine ecosystem management by using the intensively surveyed results by each taxon experts around Tamjin river. We analyzed the biological diversity, abundance, correlation among species, and ecological characteristics about 11 taxa groups including vegetation, fish, birds, mammals, etc. in the Tamjin river estuarine ecosystem. We classified vegetation types into 7 physiognomic types and 18 communities according to habitat conditions with the physical environments and salinity. In total, 1125 species including 9 species of endangered species were identified in research area. The species composition and distributional characteristics of each taxon were corresponded to the environmental characteristics of the estuarine ecosystem. Especially, the species diversity and distribution were clearly distinguished in the river according to the difference of the environmental factors such as flow rate, salinity, and soil. Despite the disturbance factors such as barrage and levees, the biodiversity and its distribution were evaluated to be high level under the current environmental conditions. However, loss or reduction of wildlife habitat due to reclamation, embankment, barrage installation and expansion of farmland has been identified as a major threat to the diversity and health of the local ecosystem. The results of this study can be used as a basic data to cope with various development pressure and damage crisis of the whole estuaries including Tamjin river.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2022.06a
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• pp.327-328
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• 2022

The recent spread of the corona pandemic and a temporary surge in demand for consumer goods have resulted in an increase in port cargo volume, and the resulting port congestion is coupled with a shortage of labor in the port, exacerbating the global supply chain chaos. Supply chain disruptions will increase logistics costs and ultimately increase global inflationary pressures. In this situation, the role of the port, which is the nodal point between land and sea, is gradually becoming more important. And fully automated ports that are operated unmanned are evaluated as being able to respond stably and flexibly by reducing operational risks in situations such as COVID-19. Therefore, this study compared the operational performance of fully automated and non-fully automated terminals within the same port before and after the corona outbreak, and analyzed the fully automated terminal was stable in actual operation. As a result of the analysis, the fully automated terminal showed stable operating efficiency in all aspects of operational performance compared to the non-fully automated terminal even under severe port congestion due to COVID-19.

• Journal of the Korean Geotechnical Society
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• v.27 no.10
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• pp.93-104
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• 2011

In this paper, a numerical procedure of probabilistic steady seepage analysis that considers the spatial variability of soil permeability is presented. The procedure extends the deterministic analysis based on the finite element method to a probabilistic approach that accounts for the uncertainties and spatial variation of the soil permeability. Two-dimensional random fields are generated based on a Karhunen-Lo$\grave{e}$ve expansion in a fashion consistent with a specified marginal distribution function and an autocorrelation function. A Monte Carlo simulation is then used to determine the statistical response based on the random fields. A series of analyses were performed to verify the application potential of the proposed method and to study the effects of uncertainty due to the spatial heterogeneity on the seepage behavior of soil foundation beneath water retaining structure with a single sheet pile wall. The results showed that the probabilistic framework can be used to efficiently consider the various flow patterns caused by the spatial variability of the soil permeability in seepage assessment for a soil foundation beneath water retaining structures.

• The Journal of the Korea Contents Association
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• v.16 no.8
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• pp.717-728
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• 2016

This study examined the factors for feelings of emptiness on Facebook use, and how these feelings are related to the user's personal attributes and the addiction to Facebook usage. For analysis, the factors for feelings of emptiness on Facebook use among college students were measured and a questionnaire was developed. After analysis, 3 factors were identified: 'isolation and loneliness', 'self-regulation disorder', and 'unreality'. Then, variables influencing the feelings of emptiness were identified. Among big 5 personalities, neuroticism, agreeableness, and openness to experience were related to the factors for feelings of emptiness. The study also found that motivations such as 'self-disclosure' and 'social pressure from others' tended to enhance the feelings of emptiness. Finally, the study examined the relationship between feelings of emptiness on Facebook use and the addiction to it. Factors of 'isolation and loneliness' and 'unreality' revealed more addiction tendency on Facebook.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.1
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• pp.83-90
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• 1998

Stage transformation characteristics of Li, K and Na-graphite deintercalation compounds (GDICs) were studied under consideration of a deintercalation mechanism of the intercalants between carbon layers. Li-graphite intercalation compounds (GICs) synthesized by a controlling temperatures and pressures have been spontaneously decomposed in the atmosphere. By X-ray differaction analysis the $d_{001}$-values of stage 1 and 2 were identified to be 3.71 and 7.06 $\AA$, respectively. After 6 weeks, the deintercalation reaction of the Li-GICs ceased and only residual compounds could be observed. K-GICs were synthesized by the modified two-bulb method resulting in structural stabilities and stage transitions. By X-ray diffraction analysis the very stable K-graphite residue compounds were observed after 10 weeks. Na-GICs with stage 1 and 2 were synthesized using the high temperature and pressure technique. The temperature dependence of a deintercalation reaction and a thermal stability of Na-GICs were discussed. The structure changes of the Na-GDICs depending on heating rates were identified by X-ray diffraction. According to the deintercalation process, the stage transformations could be attributed to irregular deintercalations of the GDICs with disordered stage.

• Analytical Science and Technology
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• v.11 no.2
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• pp.92-95
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• 1998

K-SGICs(synthetic graphite intercalation compounds) were synthesized in a modified two-bulb pyrex tube. The pressure in the two-bulb tube was maintained at approximately $10^{-3}$ torr for the reaction of potassium and graphite. Deintercalation process of the K-SGlCs obtained by the modified method was heat-treated by keeping in liquid paraffin between $25^{\circ}C$ and $1400^{\circ}C$. The thermal stability and the temperature dependence of the K-SGICs were characterized using differential scanning calorimeter(DSC) analyzer. Enthalpy and entropy for K-SGIC formations were calculated by confirming the deintercalation and thermodynamic exothermic reactions depending on the various temperatures. The structure changes and thermal stability of K-SGICs during the deintercalation reaction of potassium ions and the interlayer spaces of the synthetic graphite were identified by X-ray diffraction(XRD).

• Journal of the Korean Institute of Gas
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• v.9 no.1 s.26
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• pp.44-50
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• 2005

This paper presents integrated control and safety management system for a LNG storage tank. This system is for collecting and analyzing the temperature, pressure, and vibration signals in which are used to control and guarantee the system safety and leakage control from the inner gas tank. Based on the investigations of LNG tank related failures and accidents, we strongly recommend the modification and new development of current safety related measuring and control systems because the LNG tank is constructed bigger and bigger in recent years for the efficiency and safety increments. Thus, this paper presents newly developed integrated control and safety management system for a large LNG storage tank. This system provides the enhanced measuring and control systems, and new displacement based safety system, which may detect and control the deformation properties of tank structures. In addition, we recommend that the new integrated control and safety management system should be coupled by process integrated innovation system (PIIS) for an increased safety, efficiency, and productivity of LNG tanks.