• Title/Summary/Keyword: small-cell network

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A Design of a Cellular Neural Network for the Real Image Processing (실영상처리를 위한 셀룰러 신경망 설계)

  • Kim Seung-Soo;Jeon Heung-Woo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.2
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    • pp.283-290
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    • 2006
  • The cellular neural networks have the structure that consists of an array of the same cell which is a simple processing element, and each of the cells has local connectivity and space invariant template properties. So, it has a very suitable structure for the hardware implementation. But, it is impossible to have a one-to-one mapping between the CNN hardware processors and the pixels of the practical large image. In this paper, a $5{\times}5$ CNN hardware processor with pipeline input and output that can be applied to the time-multiplexing processing scheme, which processes the large image with a small CNN cell block, is designed. the operation of the implemented $5{\times}5$ CNN hardware processor is verified from the edge detection and the shadow detection experimentations.

Performance Evaluation of AAL Type 2 (AAL Type 2의 성능 평가)

  • Kwon, Se-Dong;Han, Man-Yoo;Park, Hyun-Min;Joo, Woo-Seok;Jun, Jong-Hun;Lee, Kang-Sun
    • The KIPS Transactions:PartC
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    • v.9C no.6
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    • pp.847-856
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    • 2002
  • Cellular network applications are growing drastically and this requires a fast and efficient transport method between the base station and the mobile switching center. One possible solution is to use ATM links. The low data rate and small-sized packets in the typical cellular applications imply that significant amount of link bandwidth would be wasted, if this small sized packet is carried by one ATM cell. For efficient operation for such cellular and low bit rate applications, a new type of ATM Adaptation Layer, AAL Type 2, has been proposed. In this paper, the principles of AAL Type 2 are briefly described along with the introduction of other alternatives which have formed the basis for this new AAL. The result from the simulation to study the performance of the AAL Type 2 is discussed from the view point of packet delay and ATM cell use efficiency. Due to the variable size of packets in this application, the fairness issue in serving variable sized packets is also discussed along with the effect of fair queueing algorithm implemented at AAL Type 2.

Spectrum Allocation and Service Control for Energy Saving Based on Large-Scale User Behavior Constraints in Heterogeneous Networks

  • Yang, Kun;Zhang, Xing;Wang, Shuo;Wang, Lin;Wang, Wenbo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.8
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    • pp.3529-3550
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    • 2016
  • In heterogeneous networks (HetNets), energy saving is vital for a sustainable network development. Many techniques, such as spectrum allocation, network planning, etc., are used to improve the network energy efficiency (EE). In this paper, micro BSs utilizing cell range expansion (CRE) and spectrum allocation are considered in multi-channel heterogeneous networks to improve EE. Hotspot region is assumed to be covered by micro BSs which can ensure that the hotspot capacity is greater than the average demand of hotspot users. The expressions of network energy efficiency are derived under shared, orthogonal and hybrid subchannel allocation schemes, respectively. Particle swarm optimization (PSO) algorithm is used to solve the optimal ratio of subchannel allocation in orthogonal and hybrid schemes. Based on the results of the optimal analysis, we propose three service control strategies on the basis of large-scale user behaviors, i.e., adjust micro cell rang expansion (AmCRE), adjust micro BSs density (AmBD) and adjust micro BSs transmit power (AmBTP). Both theoretical and simulation results show that using shared subchannel allocation scheme in AmBD strategies can obtain maximal EE with a very small area ratio. Using orthogonal subchannel allocation scheme in AmCRE strategies can obtain maximal EE when area ratio is larger. Using hybrid subchannel allocation scheme in AmCRE strategies can obtain maximal EE when area ratio is large enough. No matter which service control strategy is used, orthogonal spectrum scheme can obtain the maximal hotspot user rates.

Performance Evaluation of AAL2 Bandwidth Gain on $I_{ub}$ in UMTS Network (UMTS망의 $I_{ub}$에서 AAL2 대역이득 성능평가)

  • 이현진;김재현
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.8B
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    • pp.739-746
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    • 2004
  • An ATM/AAL2 is standardized to transmit delay sensitive application services, which has small size packet, efficiently. An AAL2 transmission scheme is used to deliver voice and data traffic on the lob interface between base station (Node-B) and Radio Network Controller (RNC) in UMTS network. To predict AAL2 performance, a detailed end-to-end UMTS network performance simulator was developed. We performed detailed simulation(cell packing density and bandwidth gain) for voice and data services in UTRAN. The results indicate that the maximum bandwidth gain in Node-B is about 17% and the bandwidth gain of AAL2 multiplexing in $I_{ub}$ for data services is less than that for voice service. Futhermore, the more offered load increase the more the bandwidth gain decreases in a concentrator.

Gut microbiota-generated metabolites: missing puzzles to hosts' health, diseases, and aging

  • Yan Zhang;Shibo Wei;Hang Zhang;Yunju Jo;Jong-Sun Kang;Ki-Tae Ha;Jongkil Joo;Hyun Joo Lee;Dongryeol Ryu
    • BMB Reports
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    • v.57 no.5
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    • pp.207-215
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    • 2024
  • The gut microbiota, an intricate community of bacteria residing in the gastrointestinal system, assumes a pivotal role in various physiological processes. Beyond its function in food breakdown and nutrient absorption, gut microbiota exerts a profound influence on immune and metabolic modulation by producing diverse gut microbiota-generated metabolites (GMGMs). These small molecules hold potential to impact host health via multiple pathways, which exhibit remarkable diversity, and have gained increasing attention in recent studies. Here, we elucidate the intricate implications and significant impacts of four specific metabolites, Urolithin A (UA), equol, Trimethylamine N-oxide (TMAO), and imidazole propionate, in shaping human health. Meanwhile, we also look into the advanced research on GMGMs, which demonstrate promising curative effects and hold great potential for further clinical therapies. Notably, the emergence of positive outcomes from clinical trials involving GMGMs, typified by UA, emphasizes their promising prospects in the pursuit of improved health and longevity. Collectively, the multifaceted impacts of GMGMs present intriguing avenues for future research and therapeutic interventions.

Radio-on-Fiber 액세스시스템 기술

  • Park, Jong Dae;Nam, Sang Sik;Park, Gwon Cheol
    • The Magazine of the IEIE
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    • v.30 no.3
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    • pp.295-295
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    • 2003
  • The advantages of using analogue optical networks for delivering radio signals from a central location to many remote antenna sites have been recognized. In a telecommnications context, radio signals may be for fixed radio access, cordless or mobile networks, but the same principles apply. By making use of the high bandwidth, low loss characteristics of optical fiber, all high frequency and signal processing functions can be performed centrally and signals can then be transported over the optical network directly at the carrier frequency. The remote sites then become very simple, requiring only optoelectronic conversion, filtering and linear amplification. This shifting of the complex functionality away from the remote site allow cheap, reliable, small and light-weight radio access points with low power consumption to be deployed. In this paper, we show that an electroabsorption modulation(EAM) may be used as a single component in such a radio access point, as a passive transceiver for small-sized cell(picocells).

Radio-on-Fiber 액세스시스템 기술

  • 박종대;남상식;박권철
    • The Magazine of the IEIE
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    • v.30 no.3
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    • pp.81-85
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    • 2003
  • The advantages of using analogue optical networks for delivering radio signals from a central location to many remote antenna sites have been recognized. In a telecommnications context, radio signals may be for fixed radio access, cordless or mobile networks, but the same principles apply. By making use of the high bandwidth, low loss characteristics of optical fiber, all high frequency and signal processing functions can be performed centrally and signals can then be transported over the optical network directly at the carrier frequency. The remote sites then become very simple, requiring only optoelectronic conversion, filtering and linear amplification. This shifting of the complex functionality away from the remote site allow cheap, reliable, small and light-weight radio access points with low power consumption to be deployed. In this paper, we show that an electroabsorption modulation(EAM) may be used as a single component in such a radio access point, as a passive transceiver for small-sized cell(picocells).

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Regulation of Immune Responses by the Activating and Inhibitory Myeloid-Associate Immunoglobuline-Like Receptors (MAIR) (CD300)

  • Shibuya, Akira;Nakahashi-Oda, Chigusa;Tahara-Hanaoka, Satoko
    • IMMUNE NETWORK
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    • v.9 no.2
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    • pp.41-45
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    • 2009
  • Activating and inhibitory cell surface receptors play important roles in regulation of immune responses. Recent progress has demonstrated that many inhibitory receptors pair with activating, as well as inhibitory, isoforms, both of whose genes are located in small clusters on a chromosome. We and others identified paired activating and inhibitory immunoglobulin-like receptors, designated myeloid-associated immunoglobulin-like receptors (MAIR) (CD300). MAIR is a multigene family consisting of nine genes on a small segment of mouse chromosome 11. MAIR family receptors are preferentially expressed on myeloid cells, including macrophages, dendritic cells, granulocytes, and bone-marrow-derived cultured mast cells, and a subset of B cells and regulate activation of these cells. Thus, MAIR plays an important role in innate immunity mediated by myeloid cells.

Interference Management with Block Diagonalization for Macro/Femto Coexisting Networks

  • Jang, Uk;Cho, Kee-Seong;Ryu, Won;Lee, Ho-Jin
    • ETRI Journal
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    • v.34 no.3
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    • pp.297-307
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    • 2012
  • A femtocell is a small cellular base station, typically designed for use in a home or small business. The random deployment of a femtocell has a critical effect on the performance of a macrocell network due to co-channel interference. Utilizing the advantage of a multiple-input multiple-output system, each femto base station (FBS) is able to form a cluster and generates a precoding matrix, which is a modified version of conventional single-cell block diagonalization, in a cooperative manner. Since interference from clustered-FBSs located at the nearby macro user equipment (MUE) is the dominant interference contributor to the coexisting networks, each cluster generates a precoding matrix considering the effects of interference on nearby MUEs. Through simulation, we verify that the proposed algorithm shows better performance respective to both MUE and femto user equipment, in terms of capacity.

A Study on Home Network Functional Model for Personal Area Network based Virtual Home Network (PAN (Personal Area Network) 기반 가상 홈 (Virtual Home) 지원을 위한 홈 네트워크 연동 모델 연구)

  • Joong Hyun Joong
    • Journal of the Korea Society of Computer and Information
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    • v.10 no.1 s.33
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    • pp.167-174
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    • 2005
  • With the progress of portable appliances such as cell phone and handhold PC, the popularization of Personal Area Network (PAN) and the diversification of services that are based on Personal Mobile Gateway (PMG) . To use home services at any time regardless of their Position, it needs a virtual home network that a home network and outside networks are finally integrated. Although interoperability among home appliances reached their service stage, research for services and middleware for new small scale network such as PAN is at an early stage. Traditional home network service/connection methods, terminal control schemes, and middlewares must be extended to accommodate PMG-based PAM. In this paper, we propose an integrated virtual home network Platform that guarantees seamless connections between home network and PAM. We also analyze indispensable functions and presents functions that should be added existent home gateway or home sewer by function.

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