• Journal of the Korean Institute of Telematics and Electronics C
• /
• v.35C no.11
• /
• pp.89-98
• /
• 1998

The enhanced resource-allocating network(ERAN) that adaptively generates hidden units of radial basis function(RBF) network for systems modeling has been proposed. The ERAN is an improved version of the resource-allocating network(RAN) that allocates new hidden units based on the novelty of observation data. The learning process of the ERAN involves allocation of new hidden units and adjusting the network parameters. The network starts with no hidden units. As observation data are received, the network adds a hidden units only if the three network growth criteria are satisfied. The network parameters are adjusted by the LMS algorithm. The performance of the ERAN is compared with the RAN for nonlinear static systems modeling problem with sequential and random learning. For two simulations, the ERAN has been shown to realize RBF networks with better accuracy with fewer hidden units.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.18 no.1
• /
• pp.11-24
• /
• 2022

Open Radio Access Network (O-RAN) standard has been proposed to separate the baseband signal processing unit from the Radio Frequency (RF) unit at base station system mainly for reducing the cost of base station systems through open-source interfaces between the two units. To satisfy the performance metrics in various scenarios, several fronthaul functional split options were presented by O-RAN. Amongst these options, the split option 7-2x is widely adopted in practical applications due to its excellent trade-off between the required bandwidth and RU overhead. In this paper, we present a hardware implementation of a base station system that is compliant with the Category B of O-RAN split option 7-2x. It consists of O-DU and O-RU implemented with a commercial off-the-shelf Digital Signal Processor and RF transceiver, respectively. The performance of the proposed base station system is evaluated in terms of Bit Error Rate and received signal power as well as the required fronthaul bandwidth. Through various experimental tests, we have observed that the proposed system reduces the fronthaul bandwidth nearly by 89.7% compared to the conventional system that dose not employ the O-RAN standard.

• Asian review of World Histories
• /
• v.2 no.2
• /
• pp.169-195
• /
• 2014

This paper presents an investigation into cross-cultural transfiguration of Buddhist faith in Goryeo Dynasty, with a focus on $\acute{S}\bar{u}$raṃgama-s$\bar{u}$tra that used to be in vogue in East Asia. There are three major types of $\acute{S}\bar{u}$raṃgama-s$\bar{u}$tra faith in Goryeo: the first one was concerned about the scripture itself including its citation and publication and the compilation of its annotation books; the second one involved establishing Buddhist rituals related to the scripture; and the final one was to create Dh$\bar{a}$ran$\bar{i}$ stone poles with Dafoding Dh$\bar{a}$ran$\bar{i}$ in Volume 7 of the scripture engraved in stone. While it was the common practice to engrave Zunsheng Dh$\bar{a}$ran$\bar{i}$ in China, the number of stone poles on which Dafoding Dh$\bar{a}$ran$\bar{i}$ was engraved was overwhelmingly large. There are a couple of reasons behind the difference: first, there was a tendency of Zunsheng Dh$\bar{a}$ran$\bar{i}$ being worshiped at the national level in Goryeo, which probably explains why the percentage of Zunsheng Dh$\bar{a}$ran$\bar{i}$ stone poles designed to pray for a personal mass for the dead by engraving Dh$\bar{a}$ran$\bar{i}$ on a stone pole was considerably low. In addition, there were esoteric sects in Goryeo, and it is estimated that they must have got involved in the establishment of Dafoding Dh$\bar{a}$ran$\bar{i}$ stone poles in the former half of Goryeo. Furthermore, the Zen sects had a deep non-Zen understanding of Esoteric Buddhism and tended to practice Dh$\bar{a}$ran$\bar{i}$ in Goryeo. It is estimated that Dafoding Dh$\bar{a}$ran$\bar{i}$ stone poles were set up in large numbers in Goryeo as the prevalence of $\acute{S}\bar{u}$raṃgama-s$\bar{u}$tra faith that continued on since the former half of Goryeo was combined with the Zen sects' active position about Dh$\bar{a}$ran$\bar{i}$.

• Information and Communications Magazine
• /
• v.30 no.9
• /
• pp.78-84
• /
• 2013

최근 4세대 이동통신은 기술/경제적인 이유로 클라우드 기지국 (또는 C-RAN: Cloud Radio Access Network) 구조를 택하는 추세이다. C-RAN은 기존 일체형 기지국에서의 MAC/PHY 기능을 담당하는 BBU(Base Band Unit)와 RF신호 송수신 만을 담당하는 RRH(Remote Radio Head)로 분리된 기지국 구조를 가지며, RRH의 무선 송수신 신호는 중앙의 BBU에 집중되어 처리된다. 본고에서는 BBU와 RRH로 분리되어 설치/운용되는 C-RAN의 구조와 기지국 가상화 개념을 소개하며, 향후 이동통신시스템에서의 기술동향과 관련하여 C-RAN에서 발생할 수 있는 이슈들을 살펴본다.

• Speech Sciences
• /
• v.12 no.1
• /
• pp.7-14
• /
• 2005

This study investigated the reading ability of Korean second-graders and the relationship between reading and phonological awareness and RAN (Rapid Automatized Naming) ability. A language-based reading assessment battery was used. Children at the end of the Korean second-grade were still at the developmental stage of decoding skill and seemed to be at Chall's stage 1. Findings indicated significant correlations between reading ability and phonological awareness and between reading ability and RAN ability. Therefore, the importance of phonological processing could be extended to syllable-based alphabetic languages.

• Journal of Communications and Networks
• /
• v.18 no.2
• /
• pp.135-149
• /
• 2016

Cloud radio access network (C-RAN) refers to the virtualization of base station functionalities by means of cloud computing. This results in a novel cellular architecture in which low-cost wireless access points, known as radio units or remote radio heads, are centrally managed by a reconfigurable centralized "cloud", or central, unit. C-RAN allows operators to reduce the capital and operating expenses needed to deploy and maintain dense heterogeneous networks. This critical advantage, along with spectral efficiency, statistical multiplexing and load balancing gains, make C-RAN well positioned to be one of the key technologies in the development of 5G systems. In this paper, a succinct overview is presented regarding the state of the art on the research on C-RAN with emphasis on fronthaul compression, baseband processing, medium access control, resource allocation, system-level considerations and standardization efforts.

• Electronics and Telecommunications Trends
• /
• v.37 no.3
• /
• pp.1-10
• /
• 2022

Traditional centralized radio access network architecture used for 4G is based on Option 8, a functional split between PHY and RF. This option is commonly used with a fronthaul interface based on common public radio interface (CPRI) specifications; however, the increased data rates in 5G make this option impractical because of the fronthaul interface's high bandwidth requirement. Since CPRI specifications have many vendor-specific options, achieving multi-vendor interoperability becomes challenging. Open RAN (O-RAN) Alliance is developing novel open fronthaul interface specifications based on the functional split Option 7-2x, one of the intra-PHY split options, to relax the bandwidth requirement of the fronthaul interface and achieve multi-vendor interoperability. This article provides a brief overview of the various functional split options for 5G fronthaul that have been reported so far and existing fronthaul technologies. Further, the technological trends in the 5G open fronthaul interface is discussed, focusing on the O-RAN Alliance specifications under standardization.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2024.05a
• /
• pp.381-382
• /
• 2024

Open RAN(Radio Access Network)을 선도적으로 연구하고 있는 O-RAN Alliance에서는 Open RAN의 E2 인터페이스에서 발생 가능한 보안 위협 중 하나로 MitM(Man-in-the-Middle) 공격을 명시하였다. 그러나 이에 대응하기 위한 보안 요구사항으로는 3계층 보안 프로토콜인 IPsec 사용을 명시하고 있으며, 2계층 공격인 ARP(Address Resolution Protocol) 스푸핑에 대한 요구사항은 명시하고 있지 않다. 따라서 본 논문에서는 MitM 공격 중 하나인 ARP 스푸핑으로부터 E2 인터페이스를 보호하기 위해, Near-RT RIC의 ARP 테이블에서 E2 인터페이스로 연결되는 장비에 대한 MAC 주소를 정적으로 설정할 수 있는 xApp을 제안한다.

• Asian-Australasian Journal of Animal Sciences
• /
• v.17 no.2
• /
• pp.271-277
• /
• 2004

The purpose of this experiment was to study the feeding behavior and running speed under various feed deprivation lengths and social environments. Three trials were conducted. Trial 1: ten pigs were trained individually to run a course and eat their feed at the end of the course. The pigs were deprived feed for 1, 5, 10 or 20 h. Trial 2: 1. Two pigs ran and ate together. Both pigs had 5 h of feed deprivation before the run (D5). 2. Two pigs ran and ate alone, but both pigs had 5 h of feed deprivation before the run (S5). 3. Two pigs ran and ate together. Both had 1 h of feed deprivation before the run (D1). 4. Two pigs ran and ate alone and both pigs had 1 h of feed deprivation before the run (S1). 5. Two pigs ran together, one had 5 h of feed deprivation, and the other had 1 h of feed deprivation before the run (51). Trial 3: 1. On the 1st day 5 pairs of pigs had 5 h feed deprivation and could eat feed together at (B) point (D1). 2. On the 2nd day the pigs ran and ate alone at (B) point after 5 h of feed deprivation. Feed was obtainable (D2). On the 3rd to 6th days, the pigs ran in pairs after 5 h of feed deprivation and only the dominant pig ate feed at point (B). The inferior pig was chased back to room and fed there. This stage was continued for four consecutive days, d 3 to 6. In trial 1, the running speed of pigs increased with the length of feed deprivation until 10 h, then being stable afterwards. Total feeding time increased with the length of feed deprivation (p<0.001). Eating speed did not increase with the length of feed deprivation (p>0.05). In trial 2, nine of ten pigs in treatment D5 ran faster than those in S5. Seven of the ten pigs in treatment S1 ran faster than those in treatment D1. The pigs in treatment D5 had significantly higher feed intake (p<0.001) and eating speed (p<0.05) than the pigs in other treatments. In trial 3, there were significant differences on running speed between D1 and D6 (p<0.01) and between D2 and D1, D3, D4 and D5. The inferior pig ran faster in D2 but from 3 to 6 it was the dominant pig that showed the greatest speed in completing the whole course. The results demonstrated that the pigs with low feeding motivation may cause low running speed to feed and low feed intake of the neighbor when compared with pigs kept individually.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.13 no.5
• /
• pp.101-105
• /
• 2013

This paper addresses QoS functions in mobile backhaul network to accommodate the diverse traffics in cell site. The traffics assigned to the switching function in RAN system, such as Ethernet frame, IP packet, and ATM cell, are segmented, and then encapsulated to transfer then to the mobile backhaul network. ISP can converge all generation traffics, such as voice, HSPA, over all-IP RAN through standard pseudowire encapsulation. These can be enhanced with diverse QoS methods as well as comprehensive monitoring and diagnostic capabilities. Therefore in this paper, QoS functions under theses operations is simulated according to the encapsulation functions.