• Journal of the Korea Institute of Military Science and Technology
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• v.11 no.5
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• pp.58-70
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• 2008

Earlier researches on Sensor Networks preferred symmetric key-based authentication schemes in consideration of limitations in network resources. However, recent advancements in cryptographic algorithms and sensor-node manufacturing techniques have opened suggestion to public key-based solutions such as Merkle tree-based schemes. These previous schemes, however, must perform the authentication process one-by-one in hierarchical manner and thus are not fit to be used as primary authentication methods in sensor networks which require mass of multiple authentications at any given time. This paper proposes a new concept of public key-based authentication that can be effectively applied to sensor networks. This scheme is based on exponential distributed data concept, a derivative from Shamir's (t, n) threshold scheme, in which the authentication of neighbouring nodes are done simultaneously while minimising resources of sensor nodes and providing network scalability. The performance advantages of this scheme on memory usage, communication overload and scalability compared to Merkle tree-based authentication are clearly demonstrated using performance analysis.

• Journal of architectural history
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• v.28 no.6
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• pp.7-18
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• 2019

This study is to find out the design concept of asymmetrical building with 4 purlins mainly in Sungkyunkwan(Confucian Shrines), Changgyeonggung palace and Changdeokgung palace The results are as follows: First, asymmetrical building with 4 purlins has the same height pillars, which was useful to control the side lenght and put a higher pillar without limit. Second, the side length of the asymmetrical building with 4 purlins is between 12 to 14 Ja[尺]. It's relatively longer than the minimum length(12 Ja) of 5 purlins architecture seen in later Joseon dynasty. Third, asymmetrical building with 4 purlins was not an anomalous structure when compared to 3 purlins and 5 purlins. It was actually a traditional style, unlike the current architectural recognition nowadays, which mainly focused on the balanced roof structure. These examples show that the architectures in Early Joseon dynasty were planned and constructed first according to the plane division that fit in a specific use or space.

• Transactions of the Korean hydrogen and new energy society
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• v.17 no.3
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• pp.263-271
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• 2006

In this study, $20\;Nm^3/hr$ scale compact hydrogen generator which can be apply to the hydrogen station was manufactured and tested. The design of $20\;Nm^3/hr$ scale compact hydrogen generator was upgraded on the base of $5\;Nm^3/hr$ scale plate hydrogen generator concept stacking the plate reactors. Ideas for improving system efficiency such as heat recovery from the exhaust, exhaust duct which is especially design for plate type reactor, reinforcement of insulation, enlargement of heat exchange area of reactor, introduction of desulphurizer reactor and PROX rector in a compact design etc. were applied. From the performance test, we can learn that the $20\;Nm^3/hr$ scale compact hydrogen generator can be operated steadily at 100% road condition and the methane conversion of over 94%(at S/C=3.75) was obtained. This result shows that the concept of plate type hydrogen generator can be scale-up to the $20\;Nm^3/hr$ scale and fit for hydrogen generator for on site hydrogen station application.

• Journal of Korean society of Dental Hygiene
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• v.20 no.5
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• pp.665-674
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• 2020

Objectives: This study investigated the perception and educational needs of the health care professionals in wake of the fourth industrial revolution. Methods: This study was conducted among 115 students from the Department of Dental Hygiene and 122 dental hygienists from Gwangju and Jeonnam, from June 25 to September 20, 2020. The questionnaire consisted of one question on the perception of the concept of the fourth industrial revolution and two questions on the influence of the fourth industrial revolution. It contained a total of eight questions on the desired education hours and education expenditure. Results: The degree of perception of the concept and influence of the fourth industrial revolution was 3.20 for both dental hygiene students and dental hygienists; the average of the two groups was the same. Regarding the educational experience, 'no experience' was the most marked response among both dental hygiene students and dental hygienists and no statistically significant difference was observed (p>0.05). Conclusions: As demanded by the changing times, it is necessary to identify the differences in educational demands of the two groups, develop educational programs according to the fourth industrial revolution, as demanded by the changing times, and apply educational programs that fit the educational needs of each group.

• Journal of the Korean Society of Propulsion Engineers
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• v.12 no.4
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• pp.42-47
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• 2008

The power control system of Smart UAV is similar to the propeller pitch governing concept of turboprop aircraft. The pilot adjusts the engine power directly and the pitch governor controls the propeller pitch to maintain the propeller rotational speed. The electronic engine controller(EEC) of PW206C engine developed for helicopter is not fit for the power control concept of Smart UAV, and therefore the manual back-up system of PW206C engine is used for the engine power control of Smart UAV. Engine performance estimation program is used to predict the control range of power lever angle(PLA) according to the variation of engine output shaft speed, flight altitude and flight speed. These data provide a guide for the PLA control in manual mode operation.

• Structural Engineering and Mechanics
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• v.41 no.6
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• pp.759-773
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• 2012

The objective of this paper is to present an energy-based method for calculating target displacement of RC structures. The method, which uses the Newmark-Hall pseudo-velocity spectrum, is called the "Pseudo-velocity Spectrum (PSVS) Method". The method is based on the energy balance concept that uses the equality of energy demand and energy capacity of the structure. First, nonlinear static analyses are performed for five, eight and ten-story RC frame structures and pushover curves are obtained. Then the pushover curves are converted to energy capacity diagrams. Seven strong ground motions that were recorded at different soil sites in Turkey are used to obtain the pseudo-acceleration and the pseudo-velocity response spectra. Later, the response spectra are idealised with the Newmark-Hall approximation. Afterwards, energy demands for the RC structures are calculated using the idealised pseudo-velocity spectrum. The displacements, obtained from the energy capacity diagrams that fit to the energy demand values of the RC structures, are accepted as the energy-based performance point of the structures. Consequently, the target displacement values determined from the PSVS Method are checked using the displacement-based successive approach in the Turkish Seismic Design Code. The results show that the target displacements of RC frame structures obtained from the PSVS Method are very close to the values calculated by the approach given in the Turkish Seismic Design Code.

• Informatization Policy
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• v.25 no.3
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• pp.95-115
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• 2018

This study aims to examine organization members' intention to violate security policies based on the Person-Environment Fit Model. This study investigated the effect of the relationship between organizational security environment and the individual security value on the intention of organizational security policy violation. The security environments are classified into the organizational information security culture and peers' behavior of security compliance, while the personal values are classified into reconstructing the conduct, distorting the consequence, and devaluing the organization as presented in the moral disengagement theory. Based on the concept of the moral disengagement theory, we measured the individual security values as a second order factor. This study found that the information security culture had a statistically significant impact on devaluing the organization, but did not have as much impact on reconstructing the conduct and distorting the consequence. Peers' behavior of security compliance had a significant impact on reconstructing the conduct, distorting the consequence and devaluing the organization, all of which also had relevant impact on the organizational members' intention of security policy violation.This study measured a persons' perception on security policy breach by presenting scenarios of password sharing that is common in many organizations. This study is expected to make practical contributions, as it deals with challenges that many organizations are actually faced with.

• Child Health Nursing Research
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• v.20 no.1
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• pp.1-10
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• 2014

Purpose: The purposes of the study were to develop and test a model which explains the relationship among factors affecting behavioral problems in elementary school children. Methods: The participants for the study were 368 elementary school children and their mothers at 3 elementary schools in one city. Data analysis was done using the SPSS 17.0 program for t-test, -test, and ANOVA and the AMOS 17.0 program for theoretical model testing. Results: The theoretical model showed a significant goodness of fit to the empirical data (Goodness of Fit Index: .96, Adjusted Goodness of Fit Index: .93 Comparative Fit Index: .95, Root Mean Square Error of Approximation: .06, Standardized Root Mean Square Residual: .02). Six paths were found to be statistically significant including from child rearing attitude to self-esteem, stress, stress coping and behavioral problems, and from self-esteem to stress and behavioral problems. Child rearing attitude showed a significant effect to behavioral problems by total effect. Self-esteem affected behavioral problems by total and direct effects. Conclusion: Child rearing attitude and selfesteem of children are important factors affecting behavioral problems in elementary school children.

• Korean Journal of Culture and Social Issue
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• v.24 no.2
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• pp.221-250
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• 2018

The purpose of this study is to find out the causes of turnover, the causes of stay, and the effects of turnover of college graduates with early careers, based on the concept of job embeddedness and their stances. For this study, semi-structured interviews were conducted with 20 college graduates with early careers and the interviews were analyzed with phenomenological analytic research. The result of the study shows that the cause of turnover intention includes fit and link which are components of job embeddedness. More specifically, turnover intention of the interviewee is affected by fit which includes whether their ability and talent are used properly and whether their vision and culture fit well those of their organization, also affected by link which includes the formal or informal mutual relationship with coworkers and superiors. Stay intention, on the other hand, includes fit which contains satisfaction about work and organization, long-term career management. Stay intention also includes sacrifice which are anxiety about uncertain future and satisfaction about being employed. As an aspect of the effect of turnover, the satisfaction and fulfillment about work which are experienced after turnover by the interviewees and the satisfaction about coworkers and the team in which the interviewees are included offset the negative effect of turnover. The result also shows that organization should consider their workers' satisfaction about the first work, their amicable relationship, and turnover cost, to improve working and living standard of colleges graduates with early careers and to prevent them from turnover.

• Journal of Physiology & Pathology in Korean Medicine
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• v.33 no.6
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• pp.311-321
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• 2019

In this paper, we try to define and classify the concepts of Convergent Research of Korean-Western Medicine (CRKWM) to clarify the goals of research. In addition, some suggestions that are necessary to promote the CRKWM were made. The results are as follows. First, the CRKWM should be used as a concept that refers to 'interdisciplinary research' jointly conducted by experts in both Korean and Western medicines beyond their own fields. Second, True CRKWM is an "eclectic combination of East-West" that combines the advantages of traditional Korean medicine and western medicine to create a new field; it is necessary to redefine the concept of 'Integrative medicine', which is used in different context by the traditional Korean medicine and western fields in Korea, as an "eclectic combination of East-West" type. Third, In order to promote the CRKWM, it is necessary to convert the current dual medical system of relativism to one of pluralism. Forth, In order for CRKWM to be promoted, methodologies, theories, and models that become the backbones of convergence should be developed. As of now, systems medicine and network science are the best fit. Fifthly, In order to promote convergent clinical research, the development of Korean-Western diagnostic model that integrates the pathologies of Western medicine and symptoms of Korean medicine is urgent. Lastly, Mutual understanding between Korean and Western medicine fields should be preceded in order for CRKWM to be stimulated.