• Journal of the Korean Regional Science Association
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• v.36 no.2
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• pp.3-12
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• 2020

Recently, metropolitanization and suburbization have been occurring mainly in large cities, and spatial miss-match between residential and employment areas has increased. Spatial miss-match is different in the metropolitan cities and other metropolitan cities in Korea. Seoul and other metropolitan cities have grown to become centers of business functions, while other metropolitan cities have been transformed into residential function centers. Accordingly, The reverse commuting phenomenon is occurring in the rural metropolitan. The reverse commuting phenomenon limits the employment opportunities of specific classes among urban residents, and cause various problems such as environmental pollution and traffic congestion. Therefore, many studies on spatial mismatch and reverse commuting have been conducted, but a number of studies have been conducted on the Seoul metropolitan area, and research on other metropolitan areas is insufficient. The purpose of this study is to analyze the cause of the commuting phenomenon in the metropolitan area of the non-metropolitan area by considering spatial mismatch and understanding the reverse commutation situation in the local metropolitan area. This study is analyzed by a multi-level model and suggests the need for management of industrial location and expansion of residence in suburban.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.19 no.2 s.72
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• pp.161-169
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• 2006

The study proposes component models in developing an efficient platform for internet-based structural analysis. Since a structural analysis requires an operation of complicated algorithms, a client-side computation using X-Internet is preferred to a server-side computation to provide a flexible service for multi-users. To compete with the user-friendly interfaces of available commercial analysis programs, a window-based interface using Smart Client was applied. Also, component-based programming was performed with the considerations on reusability and expandability so that active Preparation for future change or modification could be feasible. The components describe the whole system by subdivision and simplification. In the relationship between upper-and lower-level components and also in the relationship between components and objects, a unified interface was used to clearly classify the connection between the libraries. By performing data communication between different types of platforms using XML WebService, a conner-stone of data transfer is proposed for the future integrated CAE. The efficiency of the developed platform has been examined through a sample structural analysis and design on planar truss structures.

• Korean Journal of Health Education and Promotion
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• v.32 no.4
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• pp.67-78
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• 2015

Objectives: This study aims to examine the trends of mobile-health research in terms of community participation. Methods: A set of 24 peer-reviewed articles were identified for review. Two authors independently reviewed the articles using a literature review matrix and reexamined as a team. Review categories include: general characteristics, research methods, levels and ranges of community participation, and research topics. Results: Most of the articles were published in 2013-2014, including one domestic paper. Multidisciplinary approaches were used in 65% of the studies. Community participation was at low or mid-levels of Arnstein's participation model. In mobile-health research so far, the level of participation tends to improve as more diverse stakeholders participate in health promotion initiatives with mobile-health. The review yielded five types of mobile-health research for community health promotion: improving the quality of primary healthcare through the community health workers' capacity enhancement; improving the data collection capabilities; facilitating exchanges of community information and resources; reinforcing community identity; and monitoring physical environment of the communities. Conclusions: Although at an early stage of research development, application of mobile-health to community health promotion via participation has a potential. Multi-disciplinary approaches should be fostered for further development.

• Journal of the Korea Convergence Society
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• v.8 no.5
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• pp.117-125
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• 2017

This is a convergence study to present strategies for performance enhancement by verifying the causal relationship between the influencing factor on the performance of the healthcare-associated infection control guidelines in hospital nurses. Participants were 388 nurses recruited from 16 different tertiary and general hospitals in Korea. Data collection was conducted using self-report questionnaires and analyzed using SPSS 21.0 and AMOS 21.0 programs. The overall fitness was ${\chi}^2=99.64$ (df=14, p<.01), GFI=.94, RMSEA=.10, NFI=.84, CFI=.90. The explanatory power of predictive variables on intention were 23.8%, and those on behavior were 17.7%. As a result of this study, it was found that TPB is an appropriate theory to explain the performance of healthcare-associated infection control guidelines, and repeated studies including multi-level modeling of career experience and organizational influences on behavior with strong social characteristics are needed.

• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.12
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• pp.226-233
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• 2012

In this paper, we propose a 'linear approximation method' which is an accelerated BER (Bit Error Rate) test method for high speed interfaces, based on an analytical BER model. Both the conventional 'Q-factor estimation method' and 'linear approximation method' can predict a timing margin for $10^{-13}$ BER with an error of about 0.03UI. This linear approximation method is implemented on a hardware as an accelerated Built-In Self Test (BIST) with an internal BERT (BET Tester). While a direct measurement of a timing margin in a 3Gbps interface takes about 5.6 hours with $10^{-13}$ BER requirement and 95% confidence level, the accelerated BIST estimates a timing margin within 0.6 second without a considerable loss of accuracy. The test results show that the error between the estimated timing margin and the timing margin from an actual measurement using the internal BERT is less than 0.045UI.

• The Journal of Advanced Prosthodontics
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• v.6 no.5
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• pp.346-350
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• 2014

PURPOSE. Impact forces in implant supported FDP (fixed dental prosthesis) are higher than that of tooth supported FDPs and the compositions used in frameworks also has a paramount role for biomechanical reasons. The aim of this study was to evaluate the flexural strength of two different zirconia frameworks. MATERIALS AND METHODS. Two implant abutments with 3.8 mm and 4.5 mm platform were used as premolar and molar. They were mounted vertically in an acrylic resin block. A model with steel retainers and removable abutments was fabricated by milling machine; and 10 FDP frameworks were fabricated for each Biodenta and Cercon systems. All samples were thermo-cycled for 2000 times in $5-55^{\circ}C$ temperature and embedded in $37^{\circ}C$ artificial saliva for one week. The flexural test was done by a rod with 2 mm ending diameter which was applied to the multi-electromechanical machine. The force was inserted until observing fracture. The collected data were analyzed with SPSS software ver.15, using Weibull modulus and independent t-test with the level of significance at ${\alpha}=.05$. RESULTS. The mean load bearing capacity values were higher in Biodenta but with no significant differences (P>.05). The Biodenta frameworks showed higher load bearing capacity ($F_0=1700$) than Cercon frameworks ($F_0=1520$) but the reliability (m) was higher in Cercon (m=7.5). CONCLUSION. There was no significant difference between flexural strengths of both zirconia based framework systems; and both Biodenta and Cercon systems are capable to withstand biting force (even parafunctions) in posterior implant-supported bridges with no significant differences.

• Journal of Mechanical Science and Technology
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• v.19 no.9
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• pp.1695-1705
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• 2005

Reaction wheels and thrusters are commonly used for the satellite attitude control. Since satellites frequently need fast maneuvers, the minimum time maneuvers have been extensively studied. When the speed of attitude maneuver is restricted due to the wheel torque capacity of low level, the combinational use of wheel and thruster is considered. In this paper, minimum time optimal control performances with reaction wheels and thrusters are studied. We first identify the features of the maneuvers of the satellite with reaction wheels only. It is shown that the time-optimal maneuver for the satellite with four reaction wheels in a pyramid configuration occurs on the fashion of single axis rotation. Pseudo control logic for reaction wheels is successfully adopted for smooth and chattering-free time-optimal maneuvers. Secondly, two different thrusting logics for satellite time-optimal attitude maneuver are compared with each other: constant time-sharing thrusting logic and varying time-sharing thrusting logic. The newly suggested varying time-sharing thrusting logic is found to reduce the maneuvering time dramatically. Finally, the hybrid control with reaction wheels and thrusters are considered. The simulation results show that the simultaneous actuation of reaction wheels and thrusters with varying time-sharing logic reduces the maneuvering time enormously. Spacecraft model is Korea Multi-Purpose Satellite (KOMPSAT)-2 which is being developed in Korea as an agile maneuvering satellite.

• Journal of Digital Convergence
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• v.12 no.2
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• pp.211-221
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• 2014

The study aims to estimate the determinants of policyholder's trust for the Chinese insurance industry by structural equation model. In particular, differences in determinants of trust among Chinese life insurance and auto insurance were derived from the latent mean and multi group analysis. The result shows the most effective determinants of trust were honesty, followed by credibility which shows the compensation ability of insurance company. However, benevolence is not influence statistically on the determinants of trust of both life insurance and auto insurance. Moreover, the policyholder's trust for the insurance industry was later extended to relationship commitment such as renewal and recommendation intentions. Especially, the linkage between the level of trust and relationship commitment was the strongest in life insurance than auto insurance. Even though the result is differ based on types of insurance, in order for the insurance industry to grow stably it is importance to get trust from policyholder.

• Convergence Security Journal
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• v.15 no.4
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• pp.43-55
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• 2015

The effective cyber capability assessment methodology does not exist, it's difficult to check the current state of the our country's cyber capabilities and to establish cyber capability enhancement plan based on the result of assessment. The cyber capability assessment is necessary in order to determine the current level of the country, establish policy directions and provide the basis for effective budgeting. But assessment of national cyber capability is multi-criteria decision makink problem. In this paper develops an assessment model based on the AHP and TOPSIS. AHP is used to determine weight of the criteria and TOPSIS method is used to obtain final ranking. We also introduce the result of four major nations cyber capability assessment using the proposed methodology. The experiment used the virtual experimental data. And the result show that the proposed methodology can expand the number of criteria and alternatives for assessment and provide more sophisticated mathematical base for objective assessment comparing methodology using AHP only.

• Korean Journal of Construction Engineering and Management
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• v.10 no.2
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• pp.93-101
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• 2009

BTL projects, which has been 3 years since it was carried out in 2008, trigged the controversy on the adequacy in the calculation of disbursement for Government due to such problems as low earning rate and the burden of service level compared with the project suggestion. Thus, the purpose of this study is to offer a suggestion on the calculation system for the purpose of the standardized - expense appropriation by item and database including the antecedent study on the finance model and the feasibility in BTL projects. The system is composed of 4 steps - project management, basic database, an analysis on expense by item and the result, and an analysis on sensitivity, and it is possible to carry out a comparative analysis on single and multi alternatives by variable change along with the ground on expense calculation.