• Journal of Korean Tunnelling and Underground Space Association
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• v.25 no.2
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• pp.175-186
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• 2023

The buffer materials in disposal hole are exposed to the decay heat from spent nuclear fuels and groundwater inflow through adjacent rockmass. Since understanding of thermal-hydro-mechanical-chemical (T-H-M-C) interaction in buffer material is crucial for predicting their long-term performance and safety of disposal repository, it is necessary to investigate the heating-hydration characteristics and consequent T-H-M-C behavior of the buffer materials under disposal conditions considering geochemical factors. In response, the Korea Atomic Energy Research Institute developed a laboratory-scale 'Lab.THMC' experiment system, which characterizes the T-H-M behavior of buffer materials under different geochemical conditions by analyzing heating-hydration process and stress changes. This technical report introduces the detail design of the Lab.THMC system, summarizes preliminary experimental results, and outlines future research plans.

• Korean Security Journal
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• no.22
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• pp.231-258
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• 2010

A study apartment house inhabitants of to, crime prevention effort is done satisfaction analysis and that deduce design plan of CPTED that can overcome safe life space embodiment and criminal fear from crime in Juminin viewpoint through atomize group's interaction by background fantast. Is positive because factor analysis wave and satisfaction index of deduce universe (Total group) 8 factor are presented more than all 0, and quite was expose by level that is worth accommodating. Satisfaction index of The secondary design group (Group1) 8 factor is positive because is presented more than all 0, and mechanical access control, mechanical surveillance is level that is worth accommodating quite, and level that is proper in remainder 6 dimension appear. Can know that 1 The secondary design group(Group2) is expose by level that satisfaction characteristic of 8 factor can be presented more than all 0 and appeared positively, and accommodate quite in all dimensions. Result that analyze Two-way ANOVA satisfaction difference of environment design of group by satisfaction of the primary and the secondary design group is high in 8 all dimensions of CPTED, and satisfaction by appeared satisfaction high in group less than natural access control, 2 years of natural surveillance, and reciprocal action effect that go with group is high satisfaction in 2 years low in The secondary design group more than the primary and the secondary design group of systematic access control and natural access control, and the primary and the secondary design group appeared high in subgroup of 2 remainders. Satisfaction difference by group by crime prevention effort satisfaction of the primary and the secondary design group is high in 8 all dimensions of CPTED, and satisfaction difference by crime prevention effort appeared satisfaction high in 'A prize' group to The secondary design group, and reciprocal action efficiency is high in 'A prize' group in The secondary design group more than the primary and the secondary design group in mechanical access control, systematic access control, natural access control, territoriality reinforcement, and satisfaction of 'Between' and 'Very' group appeared high in the primary and the secondary design group.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.1
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• pp.119-125
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• 2018

The particle based computational fluid dynamics (CFD) method, which follow Lagrangian approach for fluid dynamics, fluid particle behavior by tracking all particle calculation physical quantities of each particle. According to basic concept of particle based CFD method, it is difficult to satisfy continuum theory and measure influences from neighboring particle. Article number density and weight function were used to solve aforementioned issue. Difficulties continuum mean simulate non-continuum particles such as solid including granular and sand. In this regard, the particle based CFD method modified solid particle problems by replacing viscous and surface tension forces friction and drag forces. In this paper, particle interaction model for solid particle friction model implemented to simulate solid particle problems. The broken dam problem, which is common to verify particle based CFD method, used fluid or solid particles. The angle of repose was observed in the simulation results the solid particle not fluid particle.

• The Journal of Korean Academy of Prosthodontics
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• v.44 no.6
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• pp.683-689
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• 2006

Statement of problem. Interfacial toughness is important in the mechanical property of layered dental ceramics such as core-veneered all-ceramic dental materials. The interfaces between adjacent layers must be strongly bonded to prevent delamination, however the weak interface makes delamination by the growth of lateral cracks along the interface. Purpose. The purpose of this study was to determine the effect of the reaction layer on the interfacial fracture toughness of the core/veneer structure according to the five different divesting. Materials and methods. Thirty five heat-pressed Lithia-based ceramic core bars (IPS Empress 2), $20mm{\times}3mm{\times}2mm$ were made following the five different surface divesting conditions. G1 was no dissolution or sandblasting of the interaction layer. G2 and G3 were dissolved layer with 0.2% HF in an ultrasonic unit for 15min and 30 min. G4 and G5 were dissolved layer for 15min and 30min and then same sandblasting for 60s each. We veneered bilayered ceramic bars, $20mm{\times}2.8mm{\times}3.8mm$(2mm core and 1.8mm veneer), according to the manufacturer's instruction. After polishing the specimens through $1{\mu}m$ alumina, we induced five cracks for each of five groups within the veneer close to interface under an applied indenter load of 19.6N with a Vickers microhardness indenter. Results. The results from Vickers hardness were the percentage of delamination G1:55%, G2:50%, G3:35%, G4:0% and G5:0%. SEM examination showed that the mean thickness of the reaction layer were G1 $93.5{\pm}20.6{\mu}m$, G2 $69.9{\pm}14.3{\mu}m$, G3 $59.2{\pm}20.2{\mu}m$, G4 $0.61{\pm}1.44{\mu}m$ G5 $0{\pm}0{\mu}m$. The mean interfacial delamination crack lengths were G1 $131{\pm}54.5{\mu}m$, G2 $85.2{\pm}51.3{\mu}m$, and G3 $94.9{\pm}81.8{\mu}m$. One-way ANOVA showed that there was no statistically significant difference in interfacial crack length among G1, G2 and G3(p> 0.05). Conclusion. The investment reaction layer played important role at the interfacial toughness of body ceramic bonded to Lithia-based ceramic.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.74-79
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• 2017

The fire extinguishing performance of hybrid nozzle systems is improved by injecting an extinguishing agent concentrically into the target site and, in this study, water mist is used as a water curtain to confine the droplets of the agent. In this study, we numerically investigated the effect of the foundation angle and injection pressure on the performance of a hybrid nozzle by evaluating the mean radius of the volume fractions of the agent and water mists. An experiment involving a water mist nozzle was carried out to validate the numerical method and then the droplet behaviors, e.g., stochastic collision, coalescence and breakup, were calculated with 2-way interaction Discrete Particle Modeling (DPM) in the steady state for the hybrid nozzle system. The mean radius of the water mists increased by about 40 %, whereas that of the agent decreased by about 21 %, when the injection pressure was increased from 30 bar to 60 bar. In addition, the mean radius of the agent increased by about 24 % as the foundation angle of the hybrid nozzle head increased from $30^{\circ}$ to $60^{\circ}$. As a result, it can be inferred that the injection angle and pressure are important factors for hybrid water mist designs.

• Journal of Life Science
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• v.25 no.5
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• pp.585-593
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• 2015

Stress fiber (SF) alteration is mediated by cellular receptors, which, upon interaction with the extracellular counterpart, signal to the actin cytoskeleton for remodeling. This association is mediated by a variety of scaffold and signaling factors, which control the mechanical and signaling activities of the interaction site. The heterotrimeric transmembrane lymphotoxin α1β2 (LTα1β2), a member of the tumor necrosis factor (TNF) family of cytokines, including soluble homotrimeric lymphotoxin (LT α), plays an important role in lymphoid tissue architecture. Ligation between LTα1β2 and the lymphotoxin β receptor (LTβR) activates signal-cascade in fibroblastic reticular cells (FRCs). We found LTβR stimulation using an agonistic anti-LTβR antibody alone or combined with LTα or TNFα induced changes in the actin and plasticity of cells. To clarify the involvement of myosin underlying the alteration, we analyzed the effect of myosin light chain kinase (MLCK) with an MLCK inhibitor (ML7), the phosphorylation level of myosin light chains (MLC), and the level of phospho-myosin phosphatase target subunit 1 (MYPT1) after treatment with an agonistic anti-LTβR antibody for cytoskeleton reorganization in FRCs. The inhibition of MLCK activity induced changes in the actin cytoskeleton organization and cell morphology in FRC. In addition, we showed the phosphorylation of MLC and MYPT1 was reduced by LTβR stimulation in cells. A DNA chip revealed the LTβR stimulation of FRC down-regulated transcripts of myosin and actin components. Collectively, these results suggest LTβR stimulation is linked to myosin regarding SF alteration in FRC.

• KSBB Journal
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• v.24 no.3
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• pp.227-238
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• 2009

In the recent years, some organic toxic chemicals were used for obtaining high-yield productivity in agriculture. The undegraded pesticides may remain in the agricultural foods through atmosphere, water, and soil and cause public health problems to environmental resources and human beings even at very low concentrations. Small amounts of pesticides can affect a central nervous system, resulting in immunogenic diseases, infertility problems, respiratory diseases and born marrow diseases, which can lead even to death. Monitoring of the environmental pesticide is one of the important issues for the human well-being. Several kinds of biosensors have been successfully applied to the detection of agrichemical toxicity. Also, few platforms for biocide detection have been definitely developed for the degradation and reaction of pesticides. Biochip and electrochemistry experiments involve immobilizing a receptor molecule on a solid substrate surface, and monitoring its interaction with an analyze in a sample solution. Furthermore, nanotechnology can be applied to make high-throughput analyses that are smaller, faster and sensitive than conventional assays. Some nanomaterials or nanofabricated surfaces can be coupled to biomolecules and used in antibody-based assays and enzymatic methods for pesticide residues. The operation procedure has become more convenient as it does not require labeling procedure. In this paper, we review the recent advances in agrichemical defection research and also describe the label-free biosensor for pesticides using various useful detection methods.

• Journal of Korean Academy of Nursing Administration
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• v.3 no.2
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• pp.95-107
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• 1997

For nursing as a science to establish a unique system of knowledge, nursing researchers should include the philosophical activities such as establish of nursing philosophy. For establish of philosophy nursing, the nature and realms and essential characteristics of nursing science should be made clear at first. The purpose of this study identify alienation and the situation of happen to alienation and Martin Buber Philosophy(I and Thou). Understanding of this concept should enlighten nurses to interaction and relationship problems between patients and nurse and thus lead to further toward enhancing these interaction and relationship. The alienation was serious problem in present society which was cultural, political, economical, mechanical, religious classified. The overcome of alienation in nursing situation was caring and interpersonal relationship based on Martin Buber philosophy. The essential philosophy of Martin Buber was "I and Thou" relationship. I and Thou relationship are consist of five characteristics ; 1)mutuality 2)directness 3)presentness 4)intensity 5)ineffability As health care technology becomes more sophisticated, there is a tendency to rely on monitors and machines to assess the patient's status. Therefore focus on the functioning and care of machine can result in less meaningful communication with patients. This study points to the need for health professional and patient relationship based on Martin Buber philosophy(I and Thou). This relationship may suggest that professional shoud have sincerity, concerning, respect and warm emotional toward their patients. Ultimately this study provide the basic information to contribute understanding of "I and Thou" relationship and nursing philosophy development in nursing education.

• Korean Journal of Social Welfare
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• v.59 no.1
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• pp.87-116
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• 2007

The purpose of this study is to identify the adaptation experience of foster children. This qualitative research was conducted through in-depth interview of 8 foster children in and over 4th grade. In data analysis of this qualitative study, the grounded theory suggested by Strauss and Corbin(1998) was used. The raw data collected from in-depth interview with the participants were analyzed in open coding, through theoretically sensitive and constant comparisons method. As a result, total 11 categories, 30 subcategories and 96 concepts were generated. In summary, the casual condition that caused the core phenomenon was 'family stability collapse'. The core phenomenon that foster children experience during the process of adaptation was 'marginalization'. The contextual condition that affected the outcome was 'cultural shock' and 'loyalty conflict.' The intervening condition that promote or restrain the action/interaction on core phenomenon were, 'support system', 'resilience menifestation', 'negative predestination'. The action/interaction strategy on core phenomenon were 'will to power' and 'pursuing moral superiority'. As a result, two concepts, 'mechanical adaptation to foster care environment' and 'active formation' of foster care environment' were assumed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.7
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• pp.961-967
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• 2019

This research presents an efficient method based on computational fluid dynamics (CFD) for estimating the resistance performance of a ship with a large settlement amount and a dynamic trim. The settlement of the inviscid flow analysis and the results of dynamic trim were used to set a large attitude for the ship prior to performing a viscous flow analysis; a viscous flow analysis was subsequently performed by Dynamic Fluid Body Interaction (DFBI). This method is termed as method I, in which a simple grating system can be used without employing the overset mesh technique by setting many attitudes before interpretation. Thus, method I is advantageous in reducing calculation time and improving calculation accuracy. The viscous flow analysis was performed using a commercial CFD code STAR-CCM+. Compared with the final convergence result, the first viscous flow analysis result of method I exhibited a variation of less than 1 % of resistance. The result was obtained by changing the gratings each time an attitude is changed at each calculation stage, based on the DFBI method provided to STAR-CCM+ using a simple grating system, which is not a superposed grating. This method is termed as method II. Compared with method II of resistance, method I exhibited a dif erence of 0.03-0.6 % for linear velocity. The results of method I were confirmed to be qualitatively and quantitatively appropriate through comparison with several trillion simulations.