• Journal of the Korean Chemical Society
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• v.4 no.1
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• pp.15-17
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• 1957

1. Preparation of Titanium tetrachloride; The following precesses were strictly followed as the preliminary step to obtain pure $TiOCl_2$, titanyl chloride; First, pure Titanium Oxide mixed with carbon is rolled into pills. After drying up perfectly, these pills are heated at 900∼1000${\circ}C$. And then the pills are subjected to the flow of $Cl_2$ gas in a quartz tube heated to 900-1000${\circ}C$. Thus Titanium tetrachloride is obtained. 2. Preparation of $TiOCl_2$ ; Yellowish trobrown solution is made by pouring 80 g of conc. HCl (sp.gr. 1.19) to 45 gr of Titanium tetrachloride (approx. 2 times of theoretical amount). Then this solution is kept settled for 5-days in a desiccator filled with phosphorous pentoxide at room temperature. As the colorless amorphous solid thus obtained is washed with aceton, 36.5 g of the pure salt are obtained. 3. Determination of composition. The analysis of the sample taken from the deposit desiccated gives the following data; (A) Qualitative analysis; a) $Ti(OH)_4$ is precipitated by adding NaOH in water solution of the salt. b) Adding $AgNO_3$ solution, the water solution of the salt gives white precipitate of AgCl. c) When acid and $H_2O_2$ are added, the solution turns its color to redish brown (This proves that $TiO^{++}$ was converted into $TiO^{++}$ by oxidation of $H_2O_2$. (B) Quantitative analysis; a) $Ti(OH)_4$ precipitated by $10{\%}$ NaOH isalitatsubjected consecutively to the filtration and ignition in porcelain crucible at approx. 1000${\circ}C$. , then $TiO_2$ thus formed is weighed and calculated into Ti content. b) Chlorine involved in water solution of the salt is determined by Vorhardt method. Result: The values obtained from previous analysis, devied by their atomic weight gives the following composition: Ti : Cl = 1 : 2 Therefore $TiOCl_2$ should be given as its molecular formula. 4. Summary. When $TiCl_4$ is additated into conc. HCl, $TiO^{++}$ formed exists as a stable form, and forms $TiOCl_2$. However $TiOCl_2$ is unstable to heating. When the temperature is raised to $65{\circ}C$the decomposition of the solution is accelerated, and gives $TiO_2$ aq. $TiOCl_2$ in addition is highly hygroscopic.

• Journal of the Korean Geotechnical Society
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• v.33 no.3
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• pp.49-62
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• 2017

In order to understand response of geo-structures to the freezing-thawing process in the ground, it is necessary to consider phase change of the pore water of the ground and also to understand soil interaction with structures. In this study, numerical analysis was carried out for freezing and thawing effect on the modular road system. Neumann's theoretical equation for freezing-thawing processes in porous media can be used to estimate frozen depth and heaving from basic soil properties and ground and surface temperature, but its application is limited to the case for the sediment with fully saturated condition and zero unfrozen water content. Numerical analysis of the modular road system was performed on various soil types and different ground water table as the varying freezing index. The amount of heaving in the silty soil was much larger than those in granite weathered soil or sandy soil, and lowering groundwater level reduced ground heaving induced by freezing. Numerical analysis for temperature history of the ground surface predicted residual heaving near the surface by the freeze-thaw process in silty soil. It ought to reduce stiffness and bearing capacity of the ground so that it will impair stability and serviceability of new road system. However, the amount of residual heaving was insignificant for the road system installed in weathered soil granite and sandy soil. Since modular road system is a pavement structure mounted on the supporting substructure unlike the prevalent road pavement system, strict criteria should be applied for uniform and differential settlement of the pavement system.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.28 no.5
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• pp.451-457
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• 2015

This paper presents the analytical closed form solution for the impact load of a collision between rigid bodies and its application to a spent nuclear fuel disposal canister accidentally dropped and impacted on the ground. This paper performed a study on the numerical rigid body dynamic analysis to compute the impact load between two rigid bodies, especially, the impulsive force which is applied to the spent nuclear fuel disposal canister in the accidental drop and impact event on the ground. Through this study the impulsive force which is occurring in the spent nuclear fuel disposal canister under accidental drop and impact event on the ground and required in the process of structural safety design of the canister is computed numerically. The main content of this numerical study is about the technical method how to compute the impulsive force applied to the canister under the accidental drop and impact event on the ground by using the commercial computer code for the rigid body dynamic analysis. On the basis of this study a problem to compute the impulsive force which is occurring in the canister in the case of collision with the ground is numerically treated. This numerically computed impulsive force is compared with the theoretical value, which shows a good agreement.

• Journal of Korean Society of Archives and Records Management
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• v.24 no.2
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• pp.41-63
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• 2024

This study investigated research trends in digital curation indexed in a prominent domestic academic information database. A systematic literature review was conducted on 39 academic papers published from 2009 to 2023. The review examined indexing status according to publication year, venue, academic discipline, research area distribution, research affiliation and occupation, and research types. In addition, network centrality analysis and cohesive group analysis were performed on 69 author keywords. The findings revealed several key points. First, digital curation research peaked in 2015 and 2016 with 5 publications each year, followed by a slight decrease, and then consistently produced 4 or more publications annually since 2019. Second, among the 39 studies, 25 were conducted in interdisciplinary fields, including library and information science, while 11 were in the humanities, such as miscellaneous humanities. The most prominent research areas were theoretical and infrastructural aspects, information management and services, and institutional domains. Third, digital curation research was predominantly led by university-affiliated professors and researchers, with collaborative research more prevalent than solo research. Lastly, analysis of author keywords revealed that "digital curation," "institution," and "content" were the most influential central keywords within the overall network.

• Cartoon and Animation Studies
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• s.50
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• pp.153-185
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• 2018

This study analyzed the comic "Monster" based on J. Lacan's psychoanalytic theory. J. Lacan advocated a new psychoanalytic theory through S. Freud's psychoanalytic theories and socio-cultural studies. The main theory of his theoretical background is the 'desire theory' which analyzed human desires. He distinguished human desires as desires and demands and had the basic proposition that 'human desire is the desire of the other'. J. Lacan (J. Lacan) studied in depth the relationship between oneself and others, which he defined by dividing it into an imaginary system (mirror stage), a symbolic system (Oedipus complex), and a real system (desiring subject). Based on these theories, the main purpose of this study is to analyze the comic "Monster" by Naoki Urasawa focused on the desire theory of J. Lacan based on psychoanalysis to examine what new meaning could be extracted. In order to analyze the comic "Monster", the qualitative research method was used and the method of analysis was the descriptive phenomenological method devised by Giorgi (1985). Through this analytical method, the background, characters, and symbols of "Monster" were analyzed and content analysis was performed based on the theory of Giorgi (1985) and the desire theory of J. Lacan As a result of the analysis of the meaning unit and components related to the desire theory through content analysis, the contents analysis was divided into four components: identification, reproduction of desire, alienation, and unique desire and freedom. The results of this study are summarized as follows. First, on the basis of psychoanalysis, "Monster" is classified into four elements, identification of twin characters, reproduction of desire, feeling of alienation and unique desire and freedom of characters based on desire theory of J. Lacan. Second, the characters analyzed by the desire theory of J. Lacan attempted to reproduce their desires through identification and projection of twins due to their traumatic experience when they were young. Also, the characters who felt alienated in the process of reproduction made a tragic ending to complete human desire and freedom to fill in their emptiness. This result shows that desire theory of J. Lacan based on psychoanalysis can be used as a new analytical theory, a comic analysis which suggested a new meaning. The results of this study suggest that a new field of research, a comic analysis using psychological theory, needs to be created and further studies in this field are required.

• Journal of Digital Contents Society
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• v.15 no.3
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• pp.327-338
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• 2014

This study proposes the evolution model of emerging media platform including smart media (M-IPTV, Smart TV) and IPTV, through a spiral evolution model based on the theory of the exploration & the exploitation. Authors suppose that the IP media evolved from IPTV technology, evolution of which has come through the development model of serial circular process. For explanation of this evolution, we propose the research model integrating the spiral model and the exploration & exploitation theory. Researchers define the smart media as the evolved media from IPTV, through this proposed model. We expect this model to be the theoretical base of media regulation and setting direction of future media service. Thus, this research are summed up as follows. To begin with, we classify the evolutionary stage of IPTV from the view points of service feature, regulation frame and technological characters. Secondly, we organize and confirm the research model of IPTV evolution through case analysis of the 3 cycles of each evolutionary stage. As a result, discussion of this study helps understanding mobile IP media and smart media as a post IPTV and leads the solution of various regulation issues and the development of the innovative media service and content. In addition, it can guide the government for the evolutionary direction to promote the media and the content industry.

• The Journal of the Korea Contents Association
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• v.19 no.8
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• pp.184-193
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• 2019

With the development of the information and communication technology, tourism items or products based on new technology is created or developed for tourists. This study examines tourist's satisfaction about VR program, "Secret Wind Forest", which is the story of Gotjawal, one of famous Jeju eco-tourism attraction. In order to achieve the study goal, it identified a study model from the previous studies. It collected data using survey from visitors who used VR program. The total of 227 questionnaires was utilized for data analysis. Based on the study model, it accepted five hypotheses (H1~H5), which are as follows. Firstly, individual innovativeness has a significant effect on perceived usefulness. Secondly, individual innovativeness influenced perceived usefulness, and perceived usefulness and ease influenced usage satisfaction. These results have both theoretical and practical contribution in terms of the development to tourist products using VR program. Academics can provide basic theories such as tourism activities, behaviors, and attitudes to tourism consumer-related studies on VR tourism program in terms of content application. Practically, it can help tourist marketers who want to use VR tourism program and content developers who use VR devices to construct VR program stories using tourism resources and to plan and execute contents considering the target market.

• Journal of the Korean School Mathematics Society
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• v.25 no.3
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• pp.261-278
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• 2022

The purpose of this study is to develop an assessment to diagnose difficulties in learning mathematics and misconstructions that elementary students have. With thorough theoretical background and analysis of mathematics curriculum documents, we established learning trajectories for the following content areas in grades 3 to 6: number and operation, regularity, data and chance, geometry, and measurement. Then, the research team created the assessment items targeting a specific stage in the learning trajectories and including item options to identify possible misconceptions. Based on the unified validity theory, we reported the detailed procedure of the assessment development and the evidence for the content, substance, and structural validity of the assessment. We collected the data of 675 elementary students. Rasch measurement modeling was applied, and Cronbach's alpha was estimated. We considered how to report students' assessment results to teachers appropriately and immediately, which suggested important implications for supporting teaching and learning mathematics in elementary schools. We also suggested how to use the assessment developed in this study in online and distance learning environments due to the COVID-19 pandemic.

• Information Systems Review
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• v.25 no.4
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• pp.1-25
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• 2023

The online fitness industry has experienced rapid growth in recent years, overcoming physical constraints of conventional fitness programs. The COVID-19 pandemic accelerated the trend as social distancing policies were implemented. However, as financial distress of offline gyms worsened, the Korean government implemented the "With-COVID19" policy, which lifted most of the restrictions and regulations on offline gyms, on November 1st, 2021, raising concerns about the loss of drivers for the growth of the online fitness industry. Using regression discontinuity design in time (RDDiT), this study investigates the causal effect of the "With-COVID19" policy on the viewer engagement of online fitness content. Contrary to expectations that viewer engagement would decrease, it increased by 21%. Additionally, subgroup analysis based on opportunity cost reveals heterogeneity, and the high-cost group experienced a greater increase of 32% compared to low-cost group. Based on these findings, the study provides possible mechanisms of the increase, theoretical contributions on using RDDiT in the Information Systems, and practical implications for guidelines on managing online fitness platforms and content in the era of digital transformation.

• Information Systems Review
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• v.18 no.4
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• pp.89-106
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• 2016

The latest movement in live video streaming service is mobile personal broadcasting (MPB), which refers to consumers accessing the service through social media with mobile devices, such as smartphones and tablet PCs. This service is possible through the advancements in mobile video technology and platforms. Features such as enhanced user interaction, personalization, and real-time broadcasting, combined with a greater variety of content, have led to the development of MPB. The increase in MPB users calls for research, including that on the hedonic motivational angle. This study aims to assess MPB users' intrinsic motives through the hedonic-motivation system adoption model (HMSAM) using seven factors: joy, temporal dissociation, escapism, focused immersion, perceived ease of use, perceived usefulness and intention to watch. Survey data collected from 154 samples were analyzed with statistical techniques, such as structural equation modeling. Results showed that time dissociation, escapism, and perceived ease of use have a positive relationship with heightened enjoyment. Joy significantly affects focused immersion and intention to watch. Escapism also had a statistically significant influence on focused immersion. This study contributes to the advancement of the MPB study under the HMSAM theoretical framework and offers practical suggestions to managers to enhance MPB content viewership.