• The KIPS Transactions:PartC
• /
• v.17C no.3
• /
• pp.281-290
• /
• 2010

In geographic forwarding algorithms, traditional route maintenance requires mobile nodes periodically exchange beacon messages with their neighbors. In beacon message based forwarding scheme, a longer interval reduces the number of beacons needed, but may result in significant location errors. Conversely, a shorter interval guarantees more accurate location information, but induces control overheads.Therefore, the fixed or dynamic interval scheme based forwarding schemes cannot adapt well to different mobility environments. Also, existing schemes result in the uncertainty of neighbor node's position in the forwarding table of mobile node. Therefore, this paper presents a self-adaptive location checking mechanism based proactive geo-routing algorithm for beacon-based geographic routing. Simulation results show that the proposed routing algorithm not only significantly increases the relay transmission rate but also guarantees the high end-to-end packet delivery in low and high mobility environments.

• Journal of the Korean School Mathematics Society
• /
• v.15 no.3
• /
• pp.565-584
• /
• 2012

This study investigates how the GSP helps gifted and talented students understand geometric principles and concepts during the inquiry process in the generalization of the internal triangle, and how the students logically proceeded to visualize the content during the process of generalization. Four mathematically gifted students were chosen for the study. They investigated the pattern between the area of the original triangle and the area of the internal triangle with the ratio of each sides on m:n respectively. Digital audio, video and written data were collected and analyzed. From the analysis the researcher found four results. First, the visualization used the GSP helps the students to understand the geometric principles and concepts intuitively. Second, the GSP helps the students to develop their inductive reasoning skills by proving the various cases. Third, the lessons used GSP increases interest in apathetic students and improves their mathematical communication and self-efficiency.

• Journal of Korea Society of Industrial Information Systems
• /
• v.23 no.3
• /
• pp.35-48
• /
• 2018

Recently, We will analyzed the effects of supply chain management(SCM) execution factors on the competitive advantage, focusing on display industry, which is the most intense sectors in global competition. It is important for global companies to secure corporate agility to actively respond to rapid changes in the market. This study examines whether business agility influences competitive advantage and plays a mediating role between performance and competitive advantage considering market situation.. As a result, it was analyzed that three variables of strategic factors such as strategic partnership, information sharing, and information technology have statistically significant effects on firm agility and competitive advantage. Also, it is proved that corporate agility is mediating effect on SCM execution factor and competitive advantage. This study suggests that SCM in global manufacturing industry is a Business Management System(MIS) that must be operated in enterprise management.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.9 no.1
• /
• pp.59-69
• /
• 2001

The rotor blade is modeled using a composite box beam with arbitrary wall. The active constrained damping layers are bonded to the upper and lower surfaces of the box beam to provide active and passive damping. A finite element model, based on a hybrid displacement theory, is used in the structural analysis. The theory is capable of accurately capturing the transverse shear effects in the composite primary structure, the viscoelastic and the piezoelectric layers within the ACLs. A reduced order model is derived based on the Hankel singular value. A linear quadratic Gaussian (LQG) controller is designed based on the reduced order model and the available measurement output. However, the LQG control system fails to stabilize the perturbed system although it shows good control performance at the nominal operating condition. To improve the robust stability of LQG controller, the loop transfer recovery (LTR) method is applied. Numerical results show that the proposed controller significantly improves rotor aeromechanical stability and suppresses rotor response over large variations in rotating speed by increasing lead-lag modal damping in the coupled rotor-body system.

• Archives of design research
• /
• v.18 no.1 s.59
• /
• pp.245-252
• /
• 2005

In this paper, I am going to analyze a commercial film narrative focused on a temporal order through the theory of narrative discourse by Gerard Genette. Advertisements has a special quality or feature to be convertible into mythological hyper reality to advertise an product effectively. In this process, narrative in a commercial film has visual variations using a temporal order to show an glamorously advertisements in television. The reason that narrative in a commercial film is subject to variation with a temporal order, duration, frequency is to get some aesthetic effect for making sure people see them. Under the influence of postmodernism, image making like a pop-art became the first consideration in a commercial film with the consequence that representation as a signifier came to be more important than object as a signified. As a commercial film have more sensational image as a result of visual variation, images in a commercial film became vague so that it does not explain or express an advertising concept dearly. However, those aspects have assets that it gives the TV audience a room for interpretation in advertisements by themselves.

• Journal of the Korean Society for information Management
• /
• v.32 no.1
• /
• pp.227-243
• /
• 2015

The objective of this research was to quantitatively examine the uses of first person pronouns in academic journal paper abstracts. An approximate total of 144,400 abstracts that comprising of four disciplines (chemistry, computer sciences, social sciences, and medicine) from nine countries (China, Germany, India, Japan, South Korea, France, Spain, United Kingdom, and U.S.) were quantitatively examined. By exploring the use of first person pronoun in abstracts, this paper examined the current practices among academics in the world. The results indicate the norms of each author's country and the norms of each discipline. Furthermore, the frequency-count result of this study contradicted viewpoints of academics who disapprove the use of personal person expressions in abstracts. An implication of this study is that there is a need for academics to acknowledge the uses of first person pronoun in the real world before forming personal opinions regarding the first person pronoun.

• Journal of Biomedical Engineering Research
• /
• v.19 no.4
• /
• pp.423-429
• /
• 1998

Human pharynx is unique, acting as a complex interchange between the oral cavity and esophagus, and between the nasal cavity and lungs. It is actively involved in the transport of food and liquid, producing the forces that guide that bolus into the upper esophagus and away from the adjacent larynx and lungs. This study intended to develop a biomechanical model of the human pharynx, utilizing Finite Element Method(FEM). Within each model changes in cross sectional intralumenal area were calculated and compared with the area from the computer-generated FE model. Area matching allowed estimation of intraluminal pressure gradients during swallow. The estimated pharyngeal pressure gradient varies from one region to another. The estimated pharyngeal pressure gradients showed different patterns for upper four levels and lower four levels. The contraction velocity for upper four levels is much higher than lower four levels. The higher contraction velocities and pressure gradients in the upper levels are consistent with the bolus velocities required for efficient swallow.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2008.10a
• /
• pp.76-94
• /
• 2008

This paper investigates performance of the Markowitz's portfolio selection model with applications to Korean stock market. We choose Samsung-Group-Funds and KOSPI index for performance comparison with the Markowitz's portfolio selection model. For the most recent one and a half year period between March 2007 and September 2008, KOSPI index almost remains the same with only 0.1% change, Samsung-Group-Funds shows 20.54% return, and Markowitz's model, which is composed of the same 17 Samsung group stocks, reaches 52% return. We perform sensitivity analysis on the duration of financial data and the period of portfolio change in order to maximize the return of portfolio. In conclusion, according to our empirical research results with Samsung-Group-Funds, investment by Markowitz's model, which periodically changes portfolio by using nonlinear programming with only financial data, outperforms investment by the fund manager who possesses rich experiences on stock trading and actively changes portfolio based on minute-by-minute market news and business information.

• Journal of KIISE:Information Networking
• /
• v.37 no.2
• /
• pp.99-108
• /
• 2010

The Wireless Ad Hoc network is discussed as a core technology for ubiquitous computing, and the smart tag technology is currently being actively discussed as a part of the sensor network. Thus, considering its security may advance the realization of ubiquitous computing. RFID (Radio Frequency Identification) technology using the smart tag technology as a part of the sensor network is currently in the limelight. In particular, when RFID is applied to a knowledge management system managing various data, data mobility and management convenience are ensured and automated knowledge service can be provided to users. Accordingly, this paper to proposed a secure scheme for mobility knowledge management systems using multi-agents differentiated from the existing knowledge management systems. Specifically, the proposed scheme designates user's authentication and privilege information in multi-agents and provides effective knowledge service through grouping based on user information. Moreover, even user's movement, the proposed scheme ensures service availability and provides continuous information through communication with multi-agent systems.

• The Journal of the Korea Contents Association
• /
• v.15 no.4
• /
• pp.153-167
• /
• 2015

This paper empirically analyzes specific characteristics of VOD users and their practical viewing patterns, using socio-demographic data of the current IPTV subscribers in combination with actual data of genre usage and payment. The findings revealed active viewing patterns of male, the unemployed, high earners and early adopters. In terms of preferences, households with large numbers of women prefer time shift contents, whereas households composed of more men or preschoolers prefer non-time shift contents. Likewise, the households that have more women or higher income had relatively a lot of experiences of purchasing time shift contents on one hand, but the households characterized by the larger numbers of family members or unemployed householder or young householder showed much willingness to pay premium contents on the other hand. Given the utilization of correct database, the findings offer useful information conducive to service promotion and marketing strategies to maximize VOD use in the practical dimension.