• Korean Business Review
• /
• v.19 no.2
• /
• pp.183-206
• /
• 2006

Recently, the notion of "increasing returns" has been popular not only in academia but also in industries. This notion has been drawn from prior research on network effects, which showed that the market evolution would lock in to a dominant technology. However, the long history of technological change has rarely shown the possibility of lock-in to an inferior technology. How could the market with network effects make transition between incompatible technologies regimes by escaping the lock-in? This paper analyzes the effectiveness of R&D and technological choice to investigate the sources of the dynamic capabilities in the presence of network effects and uncertain technological progress. Why does the market sometimes work against a radical technology, and why, at other times, does the market operate in favor of it? This study is to address this question by modeling the situation of two competing technologies in the presence of network effects. The numerical analysis indicates that the evolution strategy of compatibility is more likely to increase the chance of firm growth when a majority of customers are not power users or when demand for an old technology has been escalated. But when there are a substantial number of power users or when a new technology emerges before such an escalation of demand, the revolution strategy of compelling performance is more likely to be effective. The result suggests a potential mechanism for overcoming the lock-in problem. When the market exhibits some inertia to an obsolete technology, which is reinforced by the increasing customer value with respect to backward compatibility, the survival of a new technology depends on power users. When many power users are cultivated by firms' technological efforts regarding the new technology, the market is less likely to lock into an obsolete technology. Indeed, in the workstation market, where power users characterize much of the demand, innovators like Sun successfully switched to the RISC architecture.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.12 no.6
• /
• pp.2841-2860
• /
• 2018

Vehicular networks play an important role in current intelligent transportation networks and have gained much attention from academia and industry. Vehicular networks can be enhanced by Long Term Evolution-Vehicle (LTE-V) technology, which has been defined in a series of standards by the 3rd Generation Partnership Project (3GPP). LTE-V technology is a systematic and integrated V2X solution. To guarantee secure LTE-V communication, security and privacy issues must be addressed before the network is deployed. The present study aims to improve the security functionality of vehicular LTE networks by proposing an efficient and secure ID-based message authentication scheme for vehicular networks, named the ESMAV. We demonstrate its ability to simultaneously support both mutual authentication and privacy protection. In addition, the ESMAV exhibit better performance in terms of overhead computation, communication cost, and security functions, which includes privacy preservation and non-frameability.

• Journal of the Korea Society of Computer and Information
• /
• v.7 no.4
• /
• pp.33-39
• /
• 2002

The present so many systems are used by evolution of Program to expel DNC(Direct Numerical Control) Network Infra for many CNC Controller. However, these systems is an inefficiency side in case of mutual connection at a long distance between Server Computer and Machining center Also, the machining center have so many controversial points in data transmission-receiver from the NC data server. So, this thesis well constructed the remote control system from CNC(Computer Numerical Control) Controller to CAD/CAM Server Computer. This system have some kinds of merits. Firstly. the machining center's user can easily use the saved NC data transmission from the CAD/CAM Server Secondly, the remote control is possible without the mutual conversation between the CAD/CAM Server and the machining center.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.12 no.4
• /
• pp.163-169
• /
• 2016

This study is to analyze factors affecting a growth of online community with perspectives of social network. Particularly this study tries to explore structural phenomenon built by interactions between users in a certain of free board belonging to the online community, in which focuses on one's writing a comments responding on those of others. With using SNA(Social Network Analysis), the social network data calculated from users' interaction shown as their comments were collected to draw out each individual's centrality value representing the structure of the online community and also we estimated duration time and the number of each comments as a proxy variable representing growth of the online community. And then cause-and-effect relationship between individual's centrality value and the duration time and the number of each comment were analyzed. As a result of the analysis, Core-Periphery, Centralization and Reciprocity have significant effects on the duration time and the number of each comment, therefore those significant values representing online structure will give an implication to manage, to promote the online community, to forecast its evolution path and to build critical policies.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• v.4 no.3
• /
• pp.327-336
• /
• 2004

In distributed autonomous mobile robot system, each robot (predator or prey) must behave by itself according to its states and environments, and if necessary, must cooperate with other robots in order to carry out a given task. Therefore it is essential that each robot have both learning and evolution ability to adapt to dynamic environment. This paper proposes a pursuing system utilizing the artificial life concept where virtual robots emulate social behaviors of animals and insects and realize their group behaviors. Each robot contains sensors to perceive other robots in several directions and decides its behavior based on the information obtained by the sensors. In this paper, a neural network is used for behavior decision controller. The input of the neural network is decided by the existence of other robots and the distance to the other robots. The output determines the directions in which the robot moves. The connection weight values of this neural network are encoded as genes, and the fitness individuals are determined using a genetic algorithm. Here, the fitness values imply how much group behaviors fit adequately to the goal and can express group behaviors. The validity of the system is verified through simulation. Besides, in this paper, we could have observed the robots' emergent behaviors during simulation.

• ETRI Journal
• /
• v.40 no.1
• /
• pp.51-60
• /
• 2018

In Long Term Evolution (LTE) cellular networks, the transmit power control (TPC) mechanism consists of two parts: the open loop (OL) and closed loop. Most cellular networks consider OL/TPC because of its simple implementation and low operation cost. The analysis of OL/TPC parameters is essential for efficient resource management from the cellular operator's viewpoint. In this work, the impact of the OL/TPC parameters is investigated for homogeneous small cells and heterogeneous small-cell/macrocell network environments. A mathematical model is derived to compute the transmit power at the user equipment, the received power at the eNodeB, the interference in the network, and the received signal-to-interference ratio. Using the analytical platform, the effects of the OL/TPC parameters on the system performance in LTE networks are investigated. Numerical results show that, in order to achieve the best performance, it is appropriate to choose ${\alpha}_{small}=1$ and $P_{o-small}=-100dBm$ in a homogenous small-cell network. Further, the selections of ${\alpha}_{small}=1$ and $P_{o-small}=-100dBm$ in the small cells and ${\alpha}_{macro}=0.8$ and $P_{o-macro}=-100dBm$ in the macrocells seem to be suitable for heterogeneous network deployment.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.16 no.10
• /
• pp.2150-2162
• /
• 2012

In accordance with evolution of next-generation mobile Internet, 2G, 3G, 4G, and B4G mobile communication wireless access networks will be co-existed and service providers will be merged as an integrated service provider. In addition, multiple virtual service operators will appear. In order to provide complicated unified-services, in the future Internet, wireless network virtualization where network resource is shared by various service operators is necessary. Therefore, in this paper, we investigate network architectures and virtualization scenarios for wireless access network virtualization where various wireless access technologies are flexibly operated by multiple service providers over next-generation wireless access networks. We expect that the virtualization scenario and network architecture yielded from this study can play a role as a basis for development of wireless access network virtualization algorithms.

• Journal of Korea Technology Innovation Society
• /
• v.1 no.2
• /
• pp.153-164
• /
• 1998

This study attempts to provide policy makers and other interested parties with policy implications throughout an economic analysis of software sector. Chapter 2 is designed to provide an overview of market characteristics in the software sector. Chapter 3 reviews an overview of the evolution stage of the software industry and the effects these trends have on firm strategies. Chapter 4 reviews the relationships between software economic characteristics and intellectual property rights. Some suggestions are offered in the conclusion, with special attention given to an examination of market characteristics, firm strategies, government policies, and some economic factors.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.24 no.2
• /
• pp.69-80
• /
• 1999

A genetic algorithm to determine the optimal signal sequence and double cycle pattern is described. The signal sequence and double cycle pattern are used as the input for TRANSYT to find optimal signal timing at each junction in the area traffic networks, In the genetic process, the partially matched crossover and simple crossover operators are used for evolution of signal sequence and double cycle pattern respectively. A special conversion algorithm is devised to convert the signal sequence into the link-stage assignment for TRANSYT. Results from tests using data from an area traffic network in Leicester region R are given.

• Proceedings of the Korea Society of Design Studies Conference
• /
• 2000.11a
• /
• pp.28-29
• /
• 2000

디지털(digital) 기술의 발전에 의해 주도되고 있는 정보 혁명이 과거 어느 때 보다도 강력하고 빠르게 인류 역사의 흐름을 변화시키고 있음은 부인할 수 없는 사실일 것이다. 디지털 환경은 제품의 기능 및 디자인의 기대 가치에 직간접적으로 영향을 미치며 디자인 대상인 제품의 의미, 사용자와의 관계 등에 관한 재해석을 요구하고 있다.(중략)