• Journal of the Korean Geotechnical Society
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• v.25 no.12
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• pp.47-55
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• 2009

As a conventional line-fitting method, the Bouwer and Rice method has been popularly adopted to estimate the hydraulic conductivity of an aquifer through a slug test. Because a vertical cutoff wall is usually very compressible and features a small wall thickness, the Bouwer and Rice method should be carefully applied to analyzing slug test results to estimate the hydraulic conductivity of vertical cutoff walls. In addition, a relatively impermeable layer, called a filter cake, formed at the interface between the cutoff wall and the natural soil formation makes it difficult to use the Bouwer and Rice method directly. In order to overcome such limitations, the original Bouwer and Rice method has been modified by incorporating the concept of the flow net method. In this modification, the geometry condition of cutoff walls including the filter cake is effectively considered in evaluating the hydraulic conductivity of a vertical cutoff wall.

• The Journal of the Convergence on Culture Technology
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• v.10 no.2
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• pp.447-452
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• 2024

As the remarkable achievements of generative artificial intelligence technology become increasingly visible, the issue of 'controllability' in artificial intelligence is emerging as a prominent global keyword. This comes at a time when existential threats, such as the possibility of machines dominating humans, are being raised. Accordingly, this study aims to establish the groundwork for shaping a social public sphere by closely examining the concept of control, the current status, and the global landscape of artificial intelligence. It seeks to address the innovative changes anticipated in future society, with artificial intelligence technology at its core. The study aims to derive implications for preparing countermeasures against social problems and unpredictable variables that may arise from the evolution of artificial intelligence technology. It also aims to present guidelines and strategic insights for the establishment of government regulations. Furthermore, the study seeks to uncover implications for the formation of social public discourse.

• Bulletin of the Korean Chemical Society
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• v.23 no.5
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• pp.688-692
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• 2002

The aminomethylation of phenols with para-substituents by the Mannich reaction has successfully been accomplished to produce the Mannich bases 2-6. The compounds 7-8 have also been synthesized in order to identify the effect of the side arms and t he macrocycle in the complex formation. Protonation constants and stability constants of the double armed diaza-18-crown-6 ethers 2-7 with metal ions have been determined by potentiometric method at 25 $^{\circ}C$ in 95 % methanol solution. Under a basic condition (pH > 8.0), the double-armed crown ethers 2-6 revealed stronger interaction with divalent metal ions than the simple diazacrown ether 1. The stability constants with these metal ions were Co 2+ < Ni2+ < Cu2+ > Zn 2+ in increasing order, which are in accordance with the order of the Williams-Irving series. The stability constants with alkali earth metal ions were Ca 2+ < Sr 2+ < Ba 2+ in increasing order, which may be explained by the concept of size effect. It is noteworthy that the hosts 2-6, which have phenolic side arms and a macrocycle, bind stronger with metal ions than the hosts 1 and 7. On the other hand, the host 8, which has phenolic side arms with a pyperazine ring,provided comparable stability constants to those with the host 3. These facts demonstrate that phenolic side arms play a more important role than the azacrown ether ring in the process of making a complex with metal ions especially in a basic condition. In particular, the log KML values for complexation of divalent metal ions with the hosts 2-6 had the sequence, i.e., 2 (R=OCH3) < 3 (R=CH3) < 4 (R=H) < 5 (R=Cl) < 6 (R=CF3). The stability constants of the hosts 5 and 6 containing an electron-withdrawing group are larger than those of the hosts 2 and 3 containing an electron-donating group. This substituent effect is attributed to the solvent effect in which the aryl oxide with an electron-donating group has a tendency to be tied strongly with protic solvents.

• The Journal of the Korea Contents Association
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• v.16 no.10
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• pp.676-686
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• 2016

This study explored the development and applicability of a classics book reading program in the nursing curriculum as a character education program in order to enhance nursing students' holistic growth and development. An increasing number of universities in Seoul have introduced a classics book reading program as part of the curriculum and some have even designated it as an essential subject. Various such programs have been developed in addition to the regular education curriculum. The following aspects are important to consider in a classics book reading program for nursing students: trust, respect, responsibility, fairness, caring, citizenship, endurance, healthy self-concept, and self-sustained growth performance. Classics book selections need to take into account the level of the students, and the efforts should be made to ensure the accuracy of the translation and the level of students' understanding. It is difficult to form character through short-term education. Despite difficulties, character formation requires continued interest and systemic education that will lead nursing students to show inbuilt positive characteristics. Inclusion of character education in the nursing curriculum should be considered with the agreement of the university, based on political decision-making.

• Membrane Journal
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• v.6 no.4
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• pp.203-212
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• 1996

The operating parameters influencing on limiting flux was investigated in the ultrafiltration of PVA, and a new model, which is based on the Amiar model using the concept of heat transfer coefficient, was devised to overcome the limitation of gel-layer model. Using polysulfone plate-unit membrane (MWCO=20,000) and hollow-fiber membrane (MWCO= 30,000), ultrafiltration characteristics of PVA was examined with the variation of operating parameters such as cross flow velocity, transmembrane pressure, temperature, and PVA concentration. According to experimental results, the ultrafiltration of PVA through polysulfone membrane is mainly controlled by well-known phenomena of concentration polarization caused by gel-layer formation. On the contrary, in hollow fiber membrane was observed upward limiting flux which can not be explained by gel-layer model. New model was applied to predict the upward limiting flux behavior with partial satisfaction. The application of new model including viscosity correction factor, however, revealed that PVA ultrafiltration is closely related to the viscosity of permeating fluid.

• Journal of the Korean Chemical Society
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• v.61 no.1
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• pp.34-44
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• 2017

The purpose of this study was to analyze the conception type change and to investigate the effect of understanding on concepts in electrochemistry after general chemistry lessons. The significant differences in concept understanding of electrochemistry were shown in both groups. Statistically significant gains in both groups were as shown in distinguishing the chemical cell, in identifying the anode and cathode, and in understanding current formation and flow, while, significant achievements in understanding the role of the salt bridge, and the need for a standard half-cell were not found. Taking elective chemistry II in high school had an effect on understanding related concepts of electrochemistry in general chemistry lessons. It was shown that many freshmen had difficulties in understanding exact related concepts in several kinds after general chemistry lessons. In order to solve these problems, it is necessary to teach contents of the basic concepts in electrochemistry exactly and to hold supplementary lessons.

• Journal of Digital Convergence
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• v.10 no.11
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• pp.235-241
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• 2012

This paper takes the online automobile brand community in china as an example, importing 'interactivity', the concept of sociology, into online brand community study. It follows the logical way as 'How does interactivity embody among the online communities ${\rightarrow}$How about its deepening process? ${\rightarrow}$What the results of interactivity will be?', that is, 'formation of the relationship (Interaction) - deepening of the relationship (identification)-result of the relationship(brand loyalty)', makes systematic study through the method of combining theory and case analysis together, and puts forward the marketing strategic direction for online brand communities.

• Journal of the Economic Geographical Society of Korea
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• v.21 no.4
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• pp.425-437
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• 2018

Since the 1990s, clusters defined as a geographic concentration of interconnected companies, research and educational institutions, technology transfer agencies, and other public or semi-public institutions in a particular field have not only been subject to academic research, but have also become goals for various innovation and regional policies. Over the past 20 years Germany at both the Federal and $L{\ddot{a}}nder$ levels has been pursuing various cluster promotion policies and initiatives for upgrading industries' competitiveness and innovations, and some of these measures have been evaluated as successful. This study aims to examine the industrial cluster promotion policy of Germany. For this purpose, the study first outlines the concept of cluster and cluster policy theoretically, and then explores the formation and historical development of cluster polices of the German federal government.

• Journal of Korean Society of Archives and Records Management
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• v.22 no.3
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• pp.37-53
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• 2022

This study aims to discuss the issues of the detailed criteria of information subject to nondisclosure of the current National Assembly Information Disclosure Regulations and provide alternative strategies for the issues. As a theoretical study, the relevant previous studies were analyzed, the history of the National Assembly Information Disclosure Regulations was summarized, and the legal and institutional concept of the detailed criteria was discussed. Subsequently, the detailed criteria were analyzed in three aspects, namely, composition, operation, and content. For this analysis, opinions were collected by conducting interviews with five experts related to information disclosure at the National Assembly. In conclusion, the study provides alternative strategies, including a comprehensive revision of the National Assembly Information Disclosure Regulations, the necessity of revising detailed criteria, and the formation of a temporary specialized organization for revising detailed criteria.

• Journal of Engineering Education Research
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• v.26 no.6
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• pp.19-29
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• 2023

This study aims to develop and apply a metaverse-based instructional design model for the education in science and technology. It analyzed the concept and characteristics of metaverse, existing non-contact education models, and major teaching strategies systematically. Based on the prior researches, an instructional design model using metaverse is developed that presents metaverse-related teaching strategies and design principles for the before-, during-, and after-lesson phases. Then, this model was applied to a project-based learning program, conducted a perception survey on instructors and learners, and revised the metaverse instructional design model based on the results of the survey. In the Metaverse Instructional Design Model, before-lesson phase is a physical and psychological preparation stage for class participation, which includes familiarization with the Metaverse learning environment, formation of expectations for education, and self-directed pre-learning. During the lesson, to effectively deliver the lesson content, it is necessary to build confidence in the learning environment, promote learning participation, provide reference materials, perform team projects and provide feedback, digest learning content, and transfer learning content. The after-lesson phase provides strategies for ongoing interaction between learners and mentors. This study introduces a new instructional design model that utilizes metaverse and shows the potential of metaverse-based education in science and technology. It also has important implications in that it provides practical guidelines for the effective design and implementation of metaverse-based education.