• Korea Real Estate Review
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• v.28 no.4
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• pp.53-62
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• 2018

When the contractor does not receive payment for his work due to the client's funding default, he can take various legal measures against the client, in addition to refusing to transfer the building under construction to the client. To claim top payment priority and to demand the equal enforcement of the law by applying for compulsory auction or auction by exercising the right of lien, the contractor should know the construction phase or the point in time when he could exercise a lien or apply for a forced auction of the unregistered building. This study was conducted to examine qualification for lien and auction of an unregistered building. First, the general criteria for qualification for lien from qualification for ownership were examined. This means that an unregistered building can be subject to lien from a certain point in time in the construction phase, where the ownership is qualified as an independent real estate with minimal pillars, roofs, and walls. Second, the contents of the narrow and broad auction qualification were analyzed. As the contractor can select the appropriate legal means to reimburse the construction cost for the unregistered building, the results of this study are expected to provide the bases for qualification for lien on and auction of unregistered buildings.

• Applied Chemistry for Engineering
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• v.29 no.6
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• pp.759-764
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• 2018

3D porous carbon electrodes (cNPIM), prepared by solution casting of a polymer of intrinsic microporosity (PIM-1) followed by nonsolvent-induced phase separation (NIPS) and carbonization are presented. In order to effectively control the pore size of 3D porous carbon structures, cNPIM was prepared by varying the THF ratio of mixed solvents. The SEM analysis revealed that cNPIMs have a unique 3D macroporous structure having a gradient pore structure, which is expected to grant a smooth and easy ion transfer capability as an electrode material. In addition, the cNPIMs presented a very large specific surface area ($2,101.1m^2/g$) with a narrow micropore size distribution (0.75 nm). Consequently, the cNPIM exhibits a high specific capacitance (304.8 F/g) and superior rate capability of 77% in an aqueous electrolyte. We believe that our approach can provide a variety of new 3D porous carbon materials for the application to an electrochemical energy storage.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.489-496
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• 2019

This paper is a study on the evaluation of loss factor of damping treatment materials to reduce the noise and vibration for panels of railway vehicles and automobiles. In order to determine the modal parameters of damping materials, beam excitation tests were carried out using different type PVC coated aluminum and steel base beam specimens. The specimens were excited from 10 Hz to 1000 Hz frequency range using sinusoidal force, and transfer mobility data were measured by using an accelerometer. The loss factors were determined by using integrated program, based on theories of Half Power Method, Minimum Tangent Error Method, Minimum Angle Error Method and Phase Change Method, which enable to evaluate the parameters using modal circle fit and least squares error method. In the case of lower loss factor and data of linear characteristics, any method could be applied for evaluation of parameters, however the case of higher loss factor or data including non-linear characteristics, the minimum angle error method could reduce the loss factor evaluation. The obtained dynamic properties of the coating material could be used for application of Finite Element Method analyzing the noise control effects of complex structures such as carbody or under-floor boxes of rolling stock. The damping material will be very useful to control the structural noise, because the obtained modal loss factors of each mode show very good effect on over $2^{nd}$ mode frequency range.

• Tunnel and Underground Space
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• v.31 no.3
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• pp.167-183
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• 2021

It is essential to understand the complex thermo-hydro-mechanical-chemical (THMC) coupled behavior in the engineered barrier system and natural barrier system to secure the high-level radioactive waste repository's long-term safety. The heat from the high-level radioactive waste induces thermal pressurization and vaporization of groundwater in the repository system. Groundwater inflow affects the saturation variation in the engineered barrier system, and the saturation change influences the heat transfer and multi-phase flow characteristics in the buffer. Due to the complexity of the coupled behavior, a numerical simulation is a valuable tool to predict and evaluate the THMC interaction effect on the disposal system and safety assessment. To enhance the knowledge of THMC coupled interaction and validate modeling techniques in geological systems. DECOVALEX, an international cooperation project, was initiated in 1992, and KAERI has participated in the projects since 2008 in Korea. In this study, we introduced the main contents of all tasks in the DECOVALEX-2023, the current DECOVALEX phase, to the rock mechanics and geotechnical researchers in Korea.

• The Journal of KAIRB
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• v.5 no.1
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• pp.14-20
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• 2023

Purpose: To obtain fundamental data on selection tools for an internal audit and develop a new guideline. We scored the indicated points from the internal audit, identified the research progress and problems that occurred, and confirmed the validity of the risk factors involved. Methods: Of the 63 internal audits conducted by Keimyung University Dongsan Hospital from 2014 to 2021, we analyzed 55 clinical trials with an inspection checklist. We excluded 8 that failed to transfer data and refused to comply with the internal audit. The statistical summary of the collected data was verified and interpreted by using frequency analysis and a chi-square test. Result: Of total 55 cases included in the internal audit, sponsor-initiated trial (SIT) was 63.6% (vs. investigator-initiated trial [IIT]), clinical trial for investigational drug was 71.0% (vs. nonclinical or clinical trial for investigational device), domestic multicenter trial was 60.0% (vs. single center or multinational multicenter trial), and trial requisition for MFDS approval was 69.1% (vs. exception for MFDS approval). The 10 areas of the clinical trial inspection checklist (reports, protection of subjects, compliance with protocols, records, management of investigational drug and/or device, delegation of duties, qualification of investigators, management of specimen, contract-agreement and approval of protocols, and preservation of recorded documents) were weighted between 2 to 5 points. The average of the total points was 16.09±13.2 and 20 clinical trials were above the average. As a result of comparing the average of the total points weighted by year, the highest score was in 2020. The 4 factors that play significant roles in determining the internal quality were (1) principal subjects that initiated the clinical trials (p=0.049), (2) type (p=0.003), (3) phase of clinical trials (p=0.024), and (4) number of registered subjects reported at the time of continuing deliberation (p=0.019). Of the 10 areas of the clinical trial inspection checklist, 'record' was the most inappropriate and insufficient. We found more indicated points; the quality of performance declined in IIT, nonclinical trials, and other clinical trials that were not in phase I1-IV4, and the study of more than 30 registered subjects at the time of continuing review. Conclusion: If an institution has an internal audit selection tool that reflects the aforementioned risk factors, it will be possible to effectively manage high-risk studies; thereby, contributing to an efficient internal audit and improving the quality of clinical trials.

• IMMUNE NETWORK
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• v.23 no.6
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• pp.45.1-45.22
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• 2023

Interstitial lung disease (ILD) involves persistent inflammation and fibrosis, leading to respiratory failure and even death. Adult tissue-derived mesenchymal stem cells (MSCs) show potential in ILD therapeutics but obtaining an adequate quantity of cells for drug application is difficult. Daewoong Pharmaceutical's MSCs (DW-MSCs) derived from embryonic stem cells sustain a high proliferative capacity following long-term culture and expansion. The aim of this study was to investigate the therapeutic potential of DW-MSCs in experimental mouse models of ILD. DW-MSCs were expanded up to 12 passages for in vivo application in bleomycin-induced pulmonary fibrosis and collagen-induced connective tissue disease-ILD mouse models. We assessed lung inflammation and fibrosis, lung tissue immune cells, fibrosis-related gene/protein expression, apoptosis and mitochondrial function of alveolar epithelial cells, and mitochondrial transfer ability. Intravenous administration of DWMSCs consistently improved lung fibrosis and reduced inflammatory and fibrotic markers expression in both models across various disease stages. The therapeutic effect of DW-MSCs was comparable to that following daily oral administration of nintedanib or pirfenidone. Mechanistically, DW-MSCs exhibited immunomodulatory effects by reducing the number of B cells during the early phase and increasing the ratio of Tregs to Th17 cells during the late phase of bleomycin-induced pulmonary fibrosis. Furthermore, DW-MSCs exhibited anti-apoptotic effects, increased cell viability, and improved mitochondrial respiration in alveolar epithelial cells by transferring their mitochondria to alveolar epithelial cells. Our findings indicate the strong potential of DW-MSCs in the treatment of ILD owing to their high efficacy and immunomodulatory and anti-apoptotic effects.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.10 no.1
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• pp.100-112
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• 2005

Soil temperature was measured from the surface to 40 cm depth at three stations with different heights in tidal flat of Gomso Bay, west coast of Korea, for one month in every season 2004 to examine the thermal structure and the variation. Mean temperature in surface layer was higher in summer and lower in winter than in lower layer, reflecting the seasonal variation of vertically propagating structure of temperature by heating and cooling from the tidal flat surface. Standard deviation of temperature decreased from the surface to lower layer. Periodic variations of solar radiation energy and tide mainly caused short term variation of soil temperature, which was also intermittently influenced by precipitation and wind. Time series analysis showed the power spectral energy peaks at the periods of 24, 12 and 8 hours, and the strongest peak appeared at 24 hour period. These peaks can be interpreted as temperature waves forced by variations of solar radiation, diurnal tide and interaction of both variations, respectively. EOF analysis showed that the first and the second modes resolved 96% of variation of vertical temperature structure. The first mode was interpreted as the heating antl cooling from tidal flat surface and the second mode as the effect of phase lag produced by temperature wave propagation in the soil. The phase of heat transfer by 24 hour period wave, analyzed by cross spectrum, showed that mean phase difference of the temperature wave increased almost linearly with the soil depth. The time lags by the phase difference from surface to 10, 20 and 40cm were 3.2,6.5 and 9.8 hours, respectively. Vertical thermal diffusivity of temperature wave of 24 hour period was estimated using one dimensional thermal diffusion model. Average diffusivity over the soil depths and seasons resulted in $0.70{\times}10^{-6}m^2/s$ at the middle station and $0.57{\times}10^{-6}m^2/s$ at the lowest station. The depth-averaged diffusivity was large in spring and small in summer and the seasonal mean diffusivity vertically increased from 2 cm to 10 cm and decreased from 10 cm to 40 cm. Thermal propagation speeds were estimated by $8.75{\times}10^{-4}cm/s,\;3.8{\times}10{-4}cm/s,\;and\;1.7{\times}10^{-4}cm/s$ from 2 cm to 10 cm, 20 cm and 40 cm, respectively, indicating the speed reduction with depth increasing from the surface.

• Journal of the Korean Solar Energy Society
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• v.32 no.spc3
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• pp.235-244
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• 2012

This paper presents a design and simulation of bi-directional DC/DC boost converter for a fuel cell system. In this paper, we analyze the equivalent model of both a boost converter and a buck converter. Also we propose the controller of bi-directional DC-DC converter, which has buck mode of charging a capacitor and boost mode of discharging a capacitor. In order to design a controller, we draw bode plots of the control-to-output transfer function using specific parameters and incorporate proper compensator in a closed loop. As a result, it has increased PM(Phase Margin) for better dynamic performance. The proposed bi-directional DC-DC converter's 3pole-2zero compensation method has been verified with computer simulation and simulation results obtained demonstrates the validity of the proposed control scheme.

• Journal of Microbiology and Biotechnology
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• v.26 no.1
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• pp.130-138
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• 2016

The use of antibiotics in aquaculture raises environmental and food safety concerns because chronic exposure of an aquatic ecosystem to antibiotics can result in the spread of antibiotic resistance, bioaccumulation of antibiotics in the organisms, and transfer of antibiotics to humans. In an attempt to overcome these problems, high-concentration red clay was applied as an alternative antibiotic against the following common fish pathogens: Aeromonas salmonicida, Vibrio alginolyticus, and Streptococcus equinus. The growth of A. salmonicida and V. alginolyticus was retarded by red clay, whereas that of S. equinus was promoted. Phase contrast and scanning electron microscopy analyses confirmed the attachment of red clay on cell surfaces, resulting in rapid gravitational removal and cell surface damage in both A. salmonicida and V. alginolyticus, but not in S. equinus. Different cell wall properties of grampositive species may explain the unharmed cell surface of S. equinus. Significant levels of oxidative stress were generated in only the former two species, whereas significant changes in membrane permeability were found only in S. equinus, probably because of its physiological adaptation. The bacterial communities in water samples from Oncorhynchus mykiss aquacultures supplemented with red clay showed similar structure and diversity as those from oxytetracycline-treated water. Taken together, the antibiotic effects of high concentrations of red clay in aquaculture can be attributed to gravitational removal, cell surface damage, and oxidative stress production, and suggest that red clay may be used as an alternative for antibiotics in aquaculture.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.1
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• pp.202-210
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• 2014

This paper is to discover selection indicator for academia-industrial cooperation R&D project. Existing Project lacks careful consideration for participant enterprise. But, This project must be focused on enterprise for the goal of project is to improve business competition. Therefore, we analyze the survey result of enterprise satisfaction and deduct the factor of satisfaction by statistical analysis like One-way ANOVA and Regression. The study says that collaboration time, the time of planning of commercialization, technology transfer and the level of goal achievement improve enterprise satisfaction. And it implies needs for plan of manpower input and commercialization at the selecting phase. This paper is significant that it can improve project system by satisfaction. We expect that this result is utilized by planning and management.