• Journal of Communications and Networks
• /
• v.8 no.4
• /
• pp.432-441
• /
• 2006

As the community antenna television (CATV) networks becomes ubiquitous, instead of constructing an entirely new broadband network infrastructure, it has emerged as one of the rapid and economic technologies to interconnecting heterogeneous network to provide broadband access to subscribers. How to support ubiquitous real-time multimedia applications, especially in a heavy traffic environment, becomes a critical issue in modern CATV networks. In this paper, we propose a time guaranteed and efficient upstream minislots allocation algorithm for supporting quality-of-service (QoS) traffic over data over cable service interface specification (DOCSIS) CATV networks to fulfill the needs of realtime interactive services, such as video telephony, video on demand (VOD), distance learning, and so on. The proposed adaptive fast expansion algorithm and the loading statistics with dynamic swapping algorithm have been shown to perform better than that of the multimedia cable network system (MCNS) DOCSIS.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.25 no.3B
• /
• pp.456-463
• /
• 2000

Bidirectional cable TV networks using HFC(Hybrid Fiber Coaxial) networks need MAC (Medium access control) protocols to have efficient access in upstream channels. In this paper, we have studied and evaluated several contention resolution algorithms and mapping of higher layer traffic described in IEEE 802.14 and MCNS (Multimedial Cable Network System) MAC protocols with respect to IP, ABR and CBR traffic types. IEEE 802.14 MAC protocol demonstrates better performance for transmitting ATM cells while the MCNS MAC protocols for the IP traffic.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.37B no.9
• /
• pp.750-759
• /
• 2012

This paper addresses the collision resolution issue to enhance the performance of wireless sensor networks based on IEEE 802.15.4 slotted CSMA/CA. Some solutions in existing work try to solve this issue by adjusting Backoff Exponent (BE) value or Backoff Period (BP). In contrast to the existing solutions, the proposed scheme in this paper aims at providing high system throughput, but also achieving efficient energy consumption of sensor nodes by using Preamble Address (PA). For this, in the proposed scheme, only one sensor node begins data packet transmission by performing PA contention phase with other nodes before sending each data packet. Our simulation results show that the proposed scheme outperforms existing algorithms in terms of energy consumption and throughput.

• Journal of the Daesoon Academy of Sciences
• /
• v.40
• /
• pp.39-76
• /
• 2022

The two religious ethics, Christianity's 'love your enemies' and Daesoon Jinrihoe's 'grievance-resolution for mutual beneficence', can be misunderstood as similar. The misunderstanding arises from these religious ethics having something in common that specifically points to a particular object, called an enemy, and contains instructions to treat that object altruistically. However, from the perspective of Religious Ethics, the two teachings are not the same. The beliefs they are based upon are different, the religious character they pursue is different, and their processes of obtaining legitimacy, logic, and implementation are different. The most distinct difference between these ethics is that the Christian ethic focuses on a victim's role whereas Daesoon Jinrihoe ethic emphasizes the roles of both victims and perpetrators. In case of 'love your enemies,' if a perpetrator turns away from a victim and believes that they would be forgiven for their sin, the victim is unlikely to practice the teaching 'love your enemies.' Accordingly, to avoid criticism over cases wherein love of an enemy is nothing but a shallow grace, the roles of the two sides should be more highlighted than that of the absolute being. As for grievance-resolution for mutual beneficence, this teaching encourages victims to resolve their grievance with a goal of mutual beneficence. The perpetrator should likewise resolve the grievances and grudges of their victim with the aim of mutual beneficence. Jeungsan especially stressed that perpetrators have to resolve 'Cheok (慼: the resentment and grievances that someone holds against the one who victimized them)' through the ethic of grievance-resolution in order for living well. In other words, 'the ethic of Cheok-resolution' is an ethic wherein the perpetrator also plays an important role in the implementation of grievance-resolution for mutual beneficence.

• ETRI Journal
• /
• v.24 no.4
• /
• pp.311-322
• /
• 2002

Presently, optical burst switching (OBS) technology is under study as a promising solution for the backbone of the optical Internet in the near future because OBS eliminates the optical buffer problem at the switching node with the help of no optical/electro/optical conversion and guarantees class of service without any buffering. To implement the OBS network, there are a lot of challenging issues to be solved. The edge router, burst offset time management, and burst assembly mechanism are critical issues. In addition, the core router needs data burst and control header packet scheduling, a protection and restoration mechanism, and a contention resolution scheme. In this paper, we focus on the burst assembly mechanism. We present a novel data burst generation algorithm that uses hysteresis characteristics in the queueing model for the ingress edge node in optical burst switching networks. Simulation with Poisson and self-similar traffic models shows that this algorithm adaptively changes the data burst size according to the offered load and offers high average data burst utilization with a lower timer operation. It also reduces the possibility of a continuous blocking problem in the bandwidth reservation request, limits the maximum queueing delay, and minimizes the required burst size by lifting up data burst utilization for bursty input IP traffic.

• Journal of Korea Multimedia Society
• /
• v.8 no.12
• /
• pp.1613-1622
• /
• 2005

Broadcasting is fundamental and effective data dissemination mechanism for route discovery, address resolution, and many other network services in mobile ad hoc networks. Although many approaches for broadcasting have been proposed to minimize the number of retransmissions, none of them guarantee the best-suited bounds of retransmissions. Appropriate use of probabilistic method can lower the chance of contention and collision among neighboring nodes, so that it reduces the number of rebroadcasts. In this paper, we propose a probabilistic approach that dynamically adjusts the rebroadcasting probability according to the distance between the sender and the receiver. While the rebroadcast probabilities of a mobile node close to sender will be set lower, the rebroadcast probabilities of a mobile node far away from sender wi1l be set to higher, The rebroadcast probability of a node wi1l be set according to the distance from sender. We evaluate the performance of proposed approach by comparing it with flooding as well as a fixed probabilistic broadcast approach. Simulation results showed that the performance of proposed scheme outperforms by about $70\%$ than flooding scheme and outperforms by about $20\%$ than fixed probabilistic scheme.

• The KIPS Transactions:PartC
• /
• v.12C no.6 s.102
• /
• pp.927-932
• /
• 2005

We investigate the effects on performance of using a partial retransmission mechanism in Optical Burst Switched(OBS) networks. In our scheme, the lost segments of a burst are retransmitted in the OBS layer. We also propose an optical resource reservation using the partial retransmission mechanism. Our scheme attempts to improve the burst contention resolution and optical channel utilization. The performance of the proposed mechanism is analyzed by NS2 simulations. Simulation results indicate that link utilization of the OBS network is improved makedly at the expense of signaling and ingress buffers.

• Proceedings of the IEEK Conference
• /
• summer
• /
• pp.310-312
• /
• 2004

Binary Exponential Back-off (BEB) scheme is widely adopted in both wire and wireless networks for collision resolution. The BEB suffers from several performance drawbacks including long packet delay and low utilization since it doubles the back-off size after each collision. In addition, operation of the BEB algorithm may lead to the last-come-first-serve result among competing users and the BEB is further unstable for every arrival rate greater than 0 due to its random access property[1,2]. In this paper, we propose a deterministic back-off algorithm to reduce contention interval as much as possible for accessing the channel without collision in the back-off process. Simulation results show that our scheme offers a higher throughput as well as a lower packet transfer delay than the BEB by taking advantage of its lower collision ratio in saturation state.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.33 no.10A
• /
• pp.956-963
• /
• 2008

In a multi-hop wireless ad hoc network broadcasting is an elementary operation to support route discovery, address resolution and other application tasks. Broadcasting by flooding may cause serious redundancy, contention, and collision in the network which is referred to as the broadcast storm problem. Many broadcasting schemes have been proposed to give better performance than simple flooding in wireless ad hoc network. How to decide whether re-broadcast or not also poses a dilemma between reachability and efficiency under different host densities. In this paper, we propose enhanced broadcasting schemes, which can reduce re-broadcast packets without loss of reachability. Simulation results show that proposed schemes can offer better reachability as well as efficiency as compared to other previous schemes.

• Journal of the Daesoon Academy of Sciences
• /
• v.29
• /
• pp.209-239
• /
• 2017

This study focuses on reviewing the concepts, roles, meanings, and values ascribed to females and femininity as observable in Daesoon thought and in Feminist theory. Especially with regards to the process of achieving gender equality through the resolution of grievance for females in Daesoon thought, the study draws positive and desirable roles within this practice by specifically examining good deeds performed by females and practical roles that females play. By doing so, this study finds a way to go from the world of mutual contention to the world of resolving grievances that have arisen due to the oppression of yin and the encouragement of yang. First wave feminism can be summarized as the inclination for equality. In Daesoon thought concerning this and from standpoint of females, the most ideal image of woman is one of a female Perfected Being who is unified with Dao and has thereby achieved perfection of her humanity apart from gender. In the Later World (Hucheon), people can get results based on their hard work regardless of gender. The enlightenment of Dao is such that it is not important to distinguish between males and females. Both of them can be 'unified with dao'. Therefore, despite the similarity, the concepts of equality in first wave feminism and the resolution of grievance for women have differences in terms of their ideal vision of equality. The representative claim in second wave feminism is 'consideration' and, in this context, 'consideration' has pronounced feminine characteristics. In Daesoon thought, this sense of 'consideration' is related to the concept of 'Jamojijeong', a term that refers to motherly affection. However, it is not simply a virtue of females and mothers, but rather the value of 'Yin (pronounced in Sino-Korean as 'Eum')' called 'Eumdeok (hidden virtue)'. Jamojijeong means that people should behave in a modest way and this helps them achieve their aims. It is also closely related with 'femininity' in the sense of Eum. One of processes spreading it socially is to propagate virtue (Podeok) and if harmony is achieved through it, then 'right yin and right yang' emerge as the precondition by which Pyeong Do (Pacification of Tao) can be realized. Furthermore, because the aspect of Pyeong is a cosmic process, it has distinct differences from the social aims of feminism and the worldly aims of other numerous ideologies. In proceeding from the Former World (Seoncheon), an era of mutual contention, to the Later World, an era of mutual beneficence, it is essential to emphasize the connection between 'harmony (Hwa)' and 'propagating virtue' as the starting point from which the perspective of Daesoon thought aiming at the principle of 'Pyeong' and 'Hwa' emerges. Herein one can discover that the realization of Daesoon thought is based on the vitalization of the feminine value of 'Jamojijeong'.