• Journal of the Korean institute of surface engineering
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• v.30 no.3
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• pp.191-201
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• 1997

Non-passivated electrolytic tinplates withour conventinal chemical treatment self-oxidize in ambient atmosphere to from yellow stain on the outermost surface during the long-term storage. The degree of yellowness of the stain increased linerly with the oxide thickness due to the interfeefence color of the $SnO_2$ Even though the thickness of the oxide layer was very thin, less than 100$\AA$ , it exerts an undesirable influence on the can-making processes, particularly the stripping behavior after ironing. Investigations were carried out on the morphologies of the coating layer, the changes in oxide thickness during successive can-making processes and the averge friction coefficients with the different oxide thinkness. These oxide layers were broken up and distributed within the bulk tin coating during the ironing process. This redistribution of the oxide layer prvented smooth pressing-aside of the tin coating layer, resulting in an increase in the ironing friction coefficient. As the friction was increased, the residual stress along the can wall thinkness(i.e., the hoop stress) was also increased. Due to both the oxibe layer accumulation, which increased the friction coefficient, and the hoop stress, can stripping efficiency without roll-back is reduced.

• Journal of the Korea Society for Simulation
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• v.22 no.3
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• pp.81-87
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• 2013

This paper is about study how to decrese surge pressure that is occurred in excavator driving motor. We used computer simulation program SimulationX. It is also about the way finding design problem and approaching a solution through interpreting shape design sensitivity analysis. Programmes are below. First of all, finding shape fault by analyzing dynamic behavior of valves installed in hydraulic driving motor which is designed now. And drawing variable which is considered sensitive to improve dynamic efficiency among a lot of shape variables. Then, targeting that variable and examining dynamic efficiency stabilization tendency with controlling it. Finally, suggesting the most effective tuning method through variable combination as there are a lot of sensitive variables.

• Management & Information Systems Review
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• v.11
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• pp.1-21
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• 2002

Corporate culture is being recognized as essential managerial resources in the future business management and in recently the attempts, though weak, of developing the corporate culture which is corresponded with their own structure and needs are being carried on by some major companies. Then, corporate culture research, drawing attention in nowadays, indicates that it attempts to analyze and search the organization matters in the basical dimension in regard to the assumptions, values and beliefs of organization and provides the solution of organizational negative effects, which have not been settled in the previews research methods of organizational behavior, and that present turbulent management environment demands the whole conversion from the previews hard style to the soft managerial style. For this reason, this study aim at identifying organizational structure and corporate culture in the business group. Futhermore, the influence of organizational structure and organizational culture are examined. The objective of this paper attempts to analyze the ways and results of strong and special culture on the organizational structure and culture. To accomplish this purpose, this study gathers in-depth data form various secondary courses. First, uncertainties in market and technology are the main sources of mimetic isomorphism. Due to the high level of uncertainty is market and technologies. Smallness in size is responsible for the low level of complexity in organizational structure. The rapid changes in market, contents of service, and tastes of customers are responsible for the low level of formalization, which enhances swift decision making and responses.

• Proceeding of EDISON Challenge
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• 2016.03a
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• pp.147-154
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• 2016

Co-nonsolvency is a puzzling phenomenon that a polymer swells in a good solvent individually, but it collapses in a mixture of good solvents. This structural transition with changing solvent environment has been drawing attention due to practical application for stimuli-responsive polymer. The aim of this work is to describe the physical origin of the co-nonsolvency. In this work, we present Monte Carlo simulations for polymer solutions by using simple and general model. We simulate linear and ring polymers to compare their co-nonsolvency behaviors. Calculating Flory exponents and bridging fractions gives a good description for polymer structures. While the polymer structure shows non-monotonous behavior with increasing the cosolvent fraction, the chemical potential decreases monotonously. This indicates that coil-to-globule transition of polymers is purely controlled by free energy and can be regarded as a thermodynamics transition. We also present that ring polymers have higher looping probability than linear polymers, thus the bridging fraction remains higher at high cosolvent fraction. Our study provides a new perspective to understand polymer structure when the polymer "dissolves well" in any solvent.

• Earthquakes and Structures
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• v.17 no.3
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• pp.307-315
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• 2019

Building prediction and control theory have been drawing the attention of many scientists over the past few years because design and control efficiency consumes the most financial and energy. In the literature, many methods have been proposed to achieve this goal by trying different control theorems, but all of these methods face some problems in correctly solving the problem. The Evolutionary Bat (EB) Algorithm is one of the recently introduced optimization methods and providing researchers to solve different types of optimization problems. This paper applies EB to the optimization of building control design. The optimized parameter is the input to the fuzzy controller, which gives the status response as an output, which in turn changes the state of the associated actuator. The novel control criterion for guarantee of the stability of the system is also derived for the demonstration in the analysis. This systematic and simplified controller design approach is the contribution for solving complex dynamic engineering system subjected to external disturbances. The experimental results show that the method achieves effective results in the design of closed-loop system. Therefore, by establishing the stability of the closed-loop system, the behavior of the closed-loop building system can be precisely predicted and stabilized.

• Nuclear Engineering and Technology
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• v.54 no.5
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• pp.1851-1859
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• 2022

Experimental research on flow characteristics of open natural circulation system was performed, to figure out the mechanism of the open natural circulation behaviors. The influence factors, such as the heating power, the inlet subcooled and the level of cooling tank on the flow characteristics of the system were examined. It was shown that within the scope of the experimental conditions, there are five flow types: single-phase stable flow, flash and geyser coexisting unstable flow, flash stable flow, flash unstable flow, and flash and boiling coexisting unstable flow. The geyser flow in flash and geyser coexisting unstable flow is different from classic geysers flow. The flow oscillation period and amplitude of the former are more regular, is a newly discovered flow pattern. By drawing the flow instability boundary diagram and sorting out the flow types, it is found that the two-phase unstable flow is mainly characterized by boiling and flash, which determine the behavior of open natural circulation respectively or jointly. Moreover, compared with full liquid level system, non-full liquid level system is more prone to boiling phenomenon, and the range of heat flux density and undercooling degree corresponding to unstable flow is larger.

• The Journal of Industrial Distribution & Business
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• v.13 no.9
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• pp.27-36
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• 2022

Purpose: The coronavirus pandemic has affected the tourism industry in a big way. The travel industry suffered intense damage from the pandemic and procedures acquainted to containing its spread because the pandemic outbreak has led to a decline in the number of tourists and a change in their behavior. At this point, this research is to investigate adequate solutions for tourism industry to overcome the crisis in a post-Covid 19 era. Research design, data and methodology: The current author gathered data from each included study to analyze and summarize the evidence when conducting a literature analysis. This stage involves gathering and reviewing intricate texts databases for the meta-analysis. Results: The current author found total five solutions from numerous literature contents, suggesting how to overcome the crisis in a post-Covid era for tourism industry. Solutions as follows, (1) Drawing beginning illustrations, (2) Introducing Government Backing Programs, (3) Increasing Promotion of Tourism Destinations, (4) Enhancing Safety and Security Measures, and (5) Improving Infrastructure and Facilities. Conclusions: This research suggests that although the global economic recession leads to reduced demand and intense competition from other sectors, the tourism industry will be well positioned to weather these challenges if practitioners of tourism organizations follow five solutions of this research.

• Journal of Korean Academy of Nursing
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• v.53 no.2
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• pp.191-207
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• 2023

Purpose: This study aimed to develop a motivational interviewing pulmonary rehabilitation program based on self-determination theory to maintain pulmonary rehabilitation-related health behaviors in patients with chronic obstructive pulmonary disease. The program was developed by reviewing the literature on pulmonary rehabilitation guidelines, drawing on the self-determinism theory to establish its contents, recruiting experts to test its validity, and conducting a preliminary survey. Methods: A quasi-experimental design was used to confirm the effect of the program. The participants were outpatients diagnosed with chronic obstructive pulmonary disease at three general hospitals in Busan. There were 33 subjects: 15 in the experimental group and 18 in the control group. The experimental group performed a motivational interviewing pulmonary rehabilitation program which comprised 11 sessions delivered over 10 weeks. The outcomes were measured using basic psychological needs, dyspnea, 6-minute walking distance, and functional status. Intervention effects were analyzed using repeated-measures ANOVA. Results: The analysis revealed significant differences between the experimental and control groups in competence among the subdomains of basic psychological needs, dyspnea during exercise, and functional status. Conclusion: The developed program affects physical conditions and can be applied as an effective clinical nursing intervention to continuously improve the pulmonary rehabilitation behavior of patients with chronic obstructive pulmonary disease.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.20 no.2
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• pp.143-153
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• 2009

This paper identifies some natural habits and patterns of children's and adolescents' information seeking and use by drawing a wide range of studies conducted with children and adolescents as study participants. The patterns reported here indicate that children's and adolescents' information seeking and use are affected by the nature of information tasks, the qualities of access tools, their cognitive ability to seek and use information, and their prior knowledge and experience about the tasks and topics given. The findings should provide insights for identifying future research issues as well as for programming the information environments particularly conducive to learning.

• Journal of Korea Foundry Society
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• v.43 no.5
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• pp.223-229
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• 2023

In this study, STS316L produced by a double-melting process involving vacuum induction melting (VIM) and vacuum arc remelting (VAR) was subjected to extrusion and drawing to form a tube and was subsequently electrolytic polished (EP). The grain size of the obtained STS316L without EP was approximately 55 ㎛, with no difference found after EP. The thickness of the EP layer was measured by AES and TEM, showing values of approximately 10 nm and 15 nm, respectively. After EP, the Cr/Fe and CrO/FeO ratios of the passive layer increased from 1.48 to 1.62 and from 2.15 to 2.26, respectively, while the surface roughness decreased significantly from 0.255 to 0.024 ㎛. Consequently, the corrosion rate decreased in both NaCl and HCl solutions after the EP process. Additionally, the amounts of eluted Cr and Fe ions were reduced from 1.2 to 0.8 ppb and 10.3 to 0.8 ppb, respectively. Furthermore, polarization tests revealed that STS316L treated with EP required a lower current density to reach a passive state, indicating that corrosion behavior was retarded.