• The Journal of the Korea Contents Association
• /
• v.15 no.9
• /
• pp.146-156
• /
• 2015

The purpose of this study was to identify the mediating effect of anger expression between covert narcissism and SNS addiction proneness. It was conducted to measure anger expression, covert narcissism, and SNS addiction proneness from 252(132 male, 120 female) university students. The mediating effect was analyzed through Preacher and Hayes' SPSS Macro and bootstrapping analysis. As a result of analysis, first, there were positive relationship among covert narcissism, anger expression, and SNS addiction proneness. Second, anger-out had significant mediating effect within the relationship of covert narcissism and SNS addiction proneness. Third, anger-out had significant mediating effect within the relationship of covert narcissism and disturbance of adaptive life and control failure, preoccupation and tolerance, avoidance of negative emotions. Forth, anger-in and anger-control had significant mediating effect within the relationship of covert narcissism and virtual life orientation and withdrawal. Implications of these results were explored in relation to the importance of covert narcissism and SNS addiction proneness. In addition, this implication and suggestions for future research are provided.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.33 no.8B
• /
• pp.646-656
• /
• 2008

In this paper, we design and verify the MAC chip of the two-stage AWG-based WDM-PON which considers 128 ONUs and 32 wavelengths. Each wavelength with the capacity of 1Gbps is allocated to ONU for downstream transmission but each wavelength for upstream transmission can be shared by four ONUs. Therefore, MAC protocol is required to avoid the collision and use the network resource efficiently among ONUs which are sharing the same wavelength. To design a request/permit-based MAC protocol, we define a unit-chip module called sub-MAC. The WDM-PON with 128 ONUs can be implemented by using 32 sub-MAC modules. The sub-MAC consists of one control unit, one receipt unit and four transmission units. The state transition diagram of the module is described by the internal/external control signals among the functional units. The function of the sub-MAC module is verified through logic simulation using ModelSIM.

• Journal of the Society of Naval Architects of Korea
• /
• v.39 no.1
• /
• pp.73-81
• /
• 2002

This study is performed to evaluate and design the vibration characteristics of the onboard machinery with resilient mountings. To reduce the vibration revel of onboard machinery with resilient mountings, it is important to evaluate and, if necessary modify vibration characteristics of the resilient mountings. In this study we have developed a program to calculate natural frequencies of the machinery with resilient mountings, forced vibration levels due to internal excitation force of the machinery itself and external excitation forces of the main engine and the propeller, and the force and motion transmissibility of the resilient mountings. The developed program can be also applied to optimal design of the resilient mountings for obtaining a target natural frequency and for achieving a minimum forced vibration level at the center of gravity of the machinery.

• Korea journal of population studies
• /
• v.35 no.1
• /
• pp.53-75
• /
• 2012

This study aims to identify and evaluate the contents of ageism and to develop instrument of ageism. Ageism instrument development remains a necessary in aging research, for the explication of actual condition of ageing. The current study describes multidimensional view of ageism toward aging and the elderly. After pre-test and review of professionals, 31 items was constructed. Data were obtained from KGSS Survey of 1535 participants. The sample was randomly divided into two group to test reliability and validity of the scale. Finally, the 23-items with seven factors were suggested, based on the internal reliability and exploratory factor analysis with the first group. Another group were conducted confirmatory factor analysis. The results showed that the final 23-item scale with seven factors had a good model fit. Development and refinement of ageism scale are necessary elements for proceeding beyond theoretical and empirical discussions in ageism. It also provides a implications for current views of ageism and strategies for reducing ageism.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.14 no.4
• /
• pp.493-498
• /
• 2004

A novel approach for path planning of a polygonal robot is presented. Traditional path planners perform extensive geometric searching to find the optimal path or to prove that there is no solution. The computation required to prove that there is no solution is equivalent to exhaustive search of the motion space, which is typically very expensive. Humans seems to use a set of several different path planning strategies to analyse the situation of the obstacles in the environment, and quickly recognize whether the path-planning problem is easy to solve, hard to solve or has no solution. This human path-planning strategies have motivated the development of the presented algorithm that combines qualitative shape reasoning and exhaustive geometric searching to speed up the path planning process. It has three planning stages consisting of identification of no-solution cases based on an enclosure test, a qualitative reasoning stage, and finally a complete search algorithm in case the previous two stages cannot determine of the existence of a solution path.

• International Commerce and Information Review
• /
• v.16 no.3
• /
• pp.381-412
• /
• 2014

Un globalization unfolds, concerns and research toward the differnces international cultures has increased. However, there is a dearth of research regarding how to nature culture align orgainzational performance with leadership style. Accordingly, this study aims to identify the relationship between leadership style and the orgainzational performance with mediating effect of national culture. Understanding the cultures of other countries is not as fast as the speed of internationalization. As globalization advances, interest and research on the characteristics of national culture differences have been increasing. One of the important challenges for business leaders is the ability to understand and deal with cross-cultural management. But there is a lack of research on cross-cultural management. In order to achieve this objective, this study, adopts Hofstede cultural dimensions, and finds the mediating effect on these transformational and transactional leadership on organizational performance.Feminism, collectivism, power distance, and uncertainty avoidance were classified into four factors of national culture has differnct mediating effect on leadership style and performance. This research has concentrated on leadership-styles and organizational performance with mediating effect of national culture.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• v.29 no.1
• /
• pp.77-83
• /
• 2005

In collision avoidance problem of a ship, collision risk model is usually set up using the interview results fron experts who sit on a simulator by varying parameters, in which DCPA and TCPA are commonly used. This method, however, has the weakness in that not only it is expensive but also it shows different results depending on the inerviewees and other navigational parameters. In this study, a fuzzy inference system is designed based on own ship's maneuverability verified fron simulation instead of interviewing navigators. The time and distance corresponding to the collision risk value on which avoidance maneuver should be started are set to the minimum marginal time at which own ship starts maneuvering and the minimum marginal distance suggested by marine traffic rules respectively. This system can be recorfigured as a nonlinearity-strengthened one by increasing the number of fuzzy membership functions.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.15 no.5
• /
• pp.83-94
• /
• 2016

Providing a voice alarm to drivers approaching a work zone could be an effective alternative to mitigate the potential safety problems of the work zone. This study conceived a voice alarm with a direction sound speaker and a field test was conducted that evaluated the feasibility of the voice alarm at a highway work zone. During the field study, we carried out on-site driver surveys to obtain drivers' perception and preference, collected approaching speeds, and measured sound level during the off-peak 2-hour for two days, respectively. The results showed that while the voice alarm has the potential to be an effective tool in improving safety, the alternative appeared to have the negative effect of noise. Further refinement to a voice alarm with a directional speaker is required to improve feasibility, and the results are expected to be utilized as basic data useful for the refinement.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.38A no.1
• /
• pp.33-43
• /
• 2013

This paper proposes a distributed MAC protocol called Carrier Sensing Multiple Access with Collision Resolution (CSMA/CR) considering fully-connected single hop network environments for next-generation wireless LAN with high density of stations. The proposed CSMA/CR is compatible with the conventional MAC protocols by observing the operation of CSMA/CA and is able to detect a collision promptly without RTS/CTS exchange by applying the technique of CSMA/CD to wireless environments. Moreover, once a collision is detected, the dedicated resource is allocated to the next transmission and so the collision that may occur again is resolved. We investigate some implementation issues for the practicality of CSMA/CR and compare it with the typical distributed MAC protocols. The simulation results show that the proposed CSMA/CR has a low overhead as detecting a collision without the RTS/CTS exploitation and achieves always the best throughput regardless of the number of access stations, by using the reservation-based collision resolution technique.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.34 no.8
• /
• pp.1129-1136
• /
• 2010

Damper springs in a drive-line absorb the impulsive torque generated when a lock-up clutch is connected directly, instead of via a fluid coupling. Design optimization and finite element analysis were performed to improve the shock- and vibration-absorption capacity of the lock-up clutch. For this purpose, a multi-body dynamics model was developed by including the main parts of a vehicle, such as an engine with a clutch, a transmission, drive shafts and wheels, and a whole mass of a vehicle. The spring constants were selected so that resonance of a system could be avoided. Damper springs were optimized on the basis of the spring constants, impulsive torques, compressed angles, spring counts, fatigue constraints, etc. Topology optimization was performed for three plates with the damper springs. The compliance was set up as an objective function, and volume fraction was fixed below 0.3. A new shape for the plates was proposed on the basis of the topology result.