WorldWideScience

Sample records for multiservice cellular networks

  1. TELECOM 1 multiservices network

    Science.gov (United States)

    Lombard, D.; Ramat, P.; Rancy, F.

    The main objectives of the TELECOM 1 French domestic satellite project are to set up a business communication network which is to carry a wide range of digital services including data, voice, and pictures between a number of small earth stations located on the subscribers' premises. The parallel development of terrestrial specialized services networks has enabled the fitting of the TELECOM 1 network with high interworking capabilities with these networks. It has also allowed TELECOM 1 to be designed as the basis of the Future Integrated Services Digital Network. The TELECOM 1 network consists of the terrestrial network, the satellite network, and the maintenance network. Various elements which include the terrestrial network; the satellite network, and its modulation, TDMA frame and terminals; the System Management Center; the signalling system; and the demand assignment operation which are involved in the operation of the multiservices network are presented. The TELECOM 1 network evolution until 1990 through the rapid development of the ISDN is discussed.

  2. Building multiservice Internet protocol virtual private networks

    Science.gov (United States)

    Cheung, William

    1999-11-01

    Multiservice Internet Protocol-based Virtual Private Networks (MIP- VPNs) with Quality of Service (QoS) are becoming a reality due to the availability of new standards from the Internet Engineering Task Force (IETF). This paper describes how components including security models, IP tunneling protocols, and service differentiation schemes fit together in order to construct such a VPN. First, the concept and rationale of VPN is presented, followed by a discussion of its supporting components. A comparison is made among the various VPN technologies.

  3. Performance Modeling for Heterogeneous Wireless Networks with Multiservice Overflow Traffic

    DEFF Research Database (Denmark)

    Huang, Qian; Ko, King-Tim; Iversen, Villy Bæk

    2009-01-01

    Performance modeling is important for the purpose of developing efficient dimensioning tools for large complicated networks. But it is difficult to achieve in heterogeneous wireless networks, where different networks have different statistical characteristics in service and traffic models....... Multiservice loss analysis based on multi-dimensional Markov chain becomes intractable in these networks due to intensive computations required. This paper focuses on performance modeling for heterogeneous wireless networks based on a hierarchical overlay infrastructure. A method based on decomposition...... of the correlated traffic is used to achieve an approximate performance modeling for multiservice in hierarchical heterogeneous wireless networks with overflow traffic. The accuracy of the approximate performance obtained by our proposed modeling is verified by simulations....

  4. DESIGN OF MULTI-SERVICE SDH NETWORKS: FORMULATION AND HEURISTICS

    Institute of Scientific and Technical Information of China (English)

    Xi Kang; Ge Ning; Feng Chongxi

    2003-01-01

    Multi-service SDH networks support both packet- and circuit-switched traffic. Op-timal design of such a network means to guarantee the circuit connections and configure a logicalpacket-switched topology with lowest congestion. This letter first formulates the problem as amixed integer linear programming, which achieves optima] solution but has high computation.Then a heuristic algorithm is proposed to yield near-optimal solution efficiently. Performance ofthe algorithm is verified by an example.

  5. Packet throughput performance of multiservice, multirate OCDMA in elastic networks

    DEFF Research Database (Denmark)

    Raddo, Thiago R.; Sanches, Anderson L.; Tafur Monroy, Idelfonso

    2016-01-01

    of both multirate techniques is proposed. The proposed formalism can be successfully applied for performance evaluation of any arbitrary number of user classes in the system as well as for both 1-D and 2-D codes. The bit error rate (BER) and packet correct probability expressions are derived considering......In this paper, the packet throughput performance of multiservice, multirate optical code-division multiple-access (OCDMA) networks is addressed based on two distinct multirate techniques, namely multilength code and multicode. A new analytical formalism to evaluate the packet throughput performance...... the multiple-access interference (MAI) as binomially distributed. The packet throughput expression, by its turn, is derived considering a Poisson distribution for the composite packet arrivals. Numerical results show that the multicode technique is a good candidate for future multiservice, multirate OCDMA...

  6. Multiuser Radio Resource Allocation for Multiservice Transmission in OFDMA-Based Cooperative Relay Networks

    Directory of Open Access Journals (Sweden)

    Zhang Xing

    2009-01-01

    Full Text Available Abstract The problem of multiservice transmission in OFDMA-based cooperative relay networks is studied comprehensively. We propose a framework to adaptively allocate power, subcarriers, and data rate in OFDMA system to maximize spectral efficiency under the constraints of satisfying multiuser multiservices' QoS requirements. Specifically, first we concentrate on the single-user scenario which considers multiservice transmission in point-to-point cooperative relay network. Based on the analysis of single-user scenario, we extend the multiservice transmission to multiuser point-to-multipoint scenario. Next, based on the framework, we propose several suboptimal radio resource allocation algorithms for multiservice transmissions in OFDMA-based cooperative relay networks to further reduce the computational complexity. Simulation results show that the proposed algorithms yield much higher spectral efficiency and much lower outage probability, which are flexible and efficient for the OFDMA-based cooperative relay system.

  7. Variable weight spectral amplitude coding for multiservice OCDMA networks

    Science.gov (United States)

    Seyedzadeh, Saleh; Rahimian, Farzad Pour; Glesk, Ivan; Kakaee, Majid H.

    2017-09-01

    The emergence of heterogeneous data traffic such as voice over IP, video streaming and online gaming have demanded networks with capability of supporting quality of service (QoS) at the physical layer with traffic prioritisation. This paper proposes a new variable-weight code based on spectral amplitude coding for optical code-division multiple-access (OCDMA) networks to support QoS differentiation. The proposed variable-weight multi-service (VW-MS) code relies on basic matrix construction. A mathematical model is developed for performance evaluation of VW-MS OCDMA networks. It is shown that the proposed code provides an optimal code length with minimum cross-correlation value when compared to other codes. Numerical results for a VW-MS OCDMA network designed for triple-play services operating at 0.622 Gb/s, 1.25 Gb/s and 2.5 Gb/s are considered.

  8. Throughput Performance Evaluation of Multiservice Multirate OCDMA in Flexible Networks

    DEFF Research Database (Denmark)

    Raddo, Thiago R.; Sanches, Anderson L.; Tafur Monroy, Idelfonso

    2016-01-01

    packet arrivals distributions, with the latter defined as benchmark. A throughput performance evaluation is carried out for two distinct user code sequences separately, namely, 1-D and 2-D multiweight multilength optical orthogonal code (MWML-OOC). Numerical results show that the Poisson approach......In this paper, new analytical formalisms to evaluate the packet throughput of multiservice multirate slotted ALOHA optical code-division multiple-access (OCDMA) networks are proposed. The proposed formalisms can be successfully applied to 1-D and 2-D OCDMA networks with any number of user classes...... underestimates the throughput performance in unacceptable levels and incorrectly predicts the number of successfully received packets for most offered load values even in favorable conditions, such as for the 2-D MWML-OOC OCDMA network with a considerably large number of simultaneous users. On the other hand...

  9. Trunk Reservation in Multi-service Networks with BPP Traffic

    DEFF Research Database (Denmark)

    Zheng, H.; Zhang, Qi; Iversen, Villy Bæk

    2006-01-01

    In this paper we develop approximate models for trunk reservation in multi-service systems with BPP (Binomial-Poisson-Pascal) multi-rate traffic streams. The approximation is a generalization of previous work by Tran-Gia & Hubner who assumed Poisson arrival processes. It is based on a generalized...... algorithm which allows for calculation of individual performance measures for each service, in particular the traffic congestion. The algorithm is numerically robust and requires a minimum of computer memory and computing time. The approximation is good when the services have equal mean service times....

  10. Experimental Evaluation of the Usage of Ad Hoc Networks as Stubs for Multiservice Networks

    Directory of Open Access Journals (Sweden)

    Miguel Almeida

    2007-03-01

    Full Text Available This paper describes an experimental evaluation of a multiservice ad hoc network, aimed to be interconnected with an infrastructure, operator-managed network. This network supports the efficient delivery of services, unicast and multicast, legacy and multimedia, to users connected in the ad hoc network. It contains the following functionalities: routing and delivery of unicast and multicast services; distributed QoS mechanisms to support service differentiation and resource control responsive to node mobility; security, charging, and rewarding mechanisms to ensure the correct behaviour of the users in the ad hoc network. This paper experimentally evaluates the performance of multiple mechanisms, and the influence and performance penalty introduced in the network, with the incremental inclusion of new functionalities. The performance results obtained in the different real scenarios may question the real usage of ad-hoc networks for more than a minimal number of hops with such a large number of functionalities deployed.

  11. Experimental Evaluation of the Usage of Ad Hoc Networks as Stubs for Multiservice Networks

    Directory of Open Access Journals (Sweden)

    Almeida Miguel

    2007-01-01

    Full Text Available This paper describes an experimental evaluation of a multiservice ad hoc network, aimed to be interconnected with an infrastructure, operator-managed network. This network supports the efficient delivery of services, unicast and multicast, legacy and multimedia, to users connected in the ad hoc network. It contains the following functionalities: routing and delivery of unicast and multicast services; distributed QoS mechanisms to support service differentiation and resource control responsive to node mobility; security, charging, and rewarding mechanisms to ensure the correct behaviour of the users in the ad hoc network. This paper experimentally evaluates the performance of multiple mechanisms, and the influence and performance penalty introduced in the network, with the incremental inclusion of new functionalities. The performance results obtained in the different real scenarios may question the real usage of ad-hoc networks for more than a minimal number of hops with such a large number of functionalities deployed.

  12. SERVICE-AWARE BASED FUZZY ADMISSION CONTROL SCHEME IN MULTI-SERVICE NETWORKS

    Institute of Scientific and Technical Information of China (English)

    Qiu Gongan; Zhang Shunyi; Liu Shidong

    2007-01-01

    Multi-service aggregated transmission is the direction of IP network. Providing different Quality of Service (QoS) assurance for different services has become a crucial problem in future network.Admission control is a vital function for multi-service IP network. This paper proposes a novel fuzzy admission control scheme based on coarse granularity service-aware technique. Different service has discriminative sensitivity to the same QoS characteristic parameter in general. The traffic class can be perceived by the service request parameter and the proposed QoS function. And requirements of different applications can be met by maintaining the life parameter. From simulation results, the proposed scheme shows a better QoS provisioning than those traditional fuzzy logic based methods under the same admission probability.

  13. A Multiservice Voice, Data, and Video Network Enabled by Optical Ethernet

    Science.gov (United States)

    Simcoe, Mitchell

    With data now approaching 60% of all aggregate traffic and expected to grow to 90% of all traffic by 2004, networks designed around all-packet architectures are being envisioned. Within this timeframe, a network vision is to deliver voice, video, and data services over a single packet-oriented network. Some entrepreneurial network providers are pursuing this vision in an even earlier timeframe. This article introduces a multiservices voice, data, and multicast video network over an Optical Ethernet architecture for residents of multidwelling units (MDU). This article reviews the network architecture for delivering these services over Optical Ethernet and addresses the challenges of handling service types with different bandwidths and latencies over a common packet-oriented infrastructure. As an example, it addresses the challenge of managing latency-intolerant traffic such as voice over IP over a common architecture as Internet data. Furthermore, it discusses the challenges of delivering over 100 channels of broadcast video as well as video on demand over the same infrastructure.

  14. Multi-service small-cell cloud wired/wireless access network based on tunable optical frequency comb

    Science.gov (United States)

    Xiang, Yu; Zhou, Kun; Yang, Liu; Pan, Lei; Liao, Zhen-wan; Zhang, Qiang

    2015-11-01

    In this paper, we demonstrate a novel multi-service wired/wireless integrated access architecture of cloud radio access network (C-RAN) based on radio-over-fiber passive optical network (RoF-PON) system, which utilizes scalable multiple- frequency millimeter-wave (MF-MMW) generation based on tunable optical frequency comb (TOFC). In the baseband unit (BBU) pool, the generated optical comb lines are modulated into wired, RoF and WiFi/WiMAX signals, respectively. The multi-frequency RoF signals are generated by beating the optical comb line pairs in the small cell. The WiFi/WiMAX signals are demodulated after passing through the band pass filter (BPF) and band stop filter (BSF), respectively, whereas the wired signal can be received directly. The feasibility and scalability of the proposed multi-service wired/wireless integrated C-RAN are confirmed by the simulations.

  15. A new convolution algorithm for loss probablity analysis in multiservice networks

    DEFF Research Database (Denmark)

    Huang, Qian; Ko, King-Tim; Iversen, Villy Bæk

    2011-01-01

    Performance analysis in multiservice loss systems generally focuses on accurate and efficient calculation methods for traffic loss probability. Convolution algorithm is one of the existing efficient numerical methods. Exact loss probabilities are obtainable from the convolution algorithm in systems...... where the bandwidth is fully shared by all traffic classes; but not available for systems with trunk reservation, i.e. part of the bandwidth is reserved for a special class of traffic. A proposal known as asymmetric convolution algorithm (ACA) has been made to overcome the deficiency of the convolution...... algorithm. It obtains an approximation of the channel occupancy distribution in multiservice systems with trunk reservation. However, the ACA approximation is only accurate with two traffic flows; increased approximation errors are observed for systems with three or more traffic flows. In this paper, we...

  16. A Non-Cooperative Approach to the Joint Subcarrier and Power Allocation Problem in Multi-Service SCFDMA Networks

    Directory of Open Access Journals (Sweden)

    E. E. Tsiropoulou

    2016-06-01

    Full Text Available In this paper a joint resource allocation problem is studied in a multi-service Single Carrier FDMA (SC-FDMA wireless network. Mobile users request various services with different Quality of Service (QoS characteristics and they determine in a distributed and non-cooperative manner a joint subcarrier and power allocation towards fulfilling their QoS prerequisites. Initially, a well-designed utility function is formulated to appropriately represent users’ diverse QoS prerequisites with respect to their requested service. The subcarriers allocation problem is solved based on a multilateral bargaining model, where users are able to select different discount factors to enter the bargaining game, thus better expressing their different needs in system resources with respect to their requested service. The subcarriers mapping is realized based either on the localized SC-FDMA method where the subcarriers are sequentially allocated to the users or the distributed SC-FDMA via considering the maximum channel gain policy, where each subcarrier is allocated to the user with the maximum channel gain. Given the subcarriers assignment, an optimization problem with respect to users’ uplink transmission power is formulated and solved, in order to determine the optimal power allocation per subcarrier assigned to each user. Finally, the performance of the proposed framework is evaluated via modeling and simulation and extensive numerical results are presented.

  17. Flat Cellular (UMTS) Networks

    NARCIS (Netherlands)

    Bosch, H.G.P.; Samuel, L.G.; Mullender, S.J.; Polakos, P.; Rittenhouse, G.

    2007-01-01

    Traditionally, cellular systems have been built in a hierarchical manner: many specialized cellular access network elements that collectively form a hierarchical cellular system. When 2G and later 3G systems were designed there was a good reason to make system hierarchical: from a cost-perspective i

  18. Heterogeneous cellular networks

    CERN Document Server

    Hu, Rose Qingyang

    2013-01-01

    A timely publication providing coverage of radio resource management, mobility management and standardization in heterogeneous cellular networks The topic of heterogeneous cellular networks has gained momentum in industry and the research community, attracting the attention of standardization bodies such as 3GPP LTE and IEEE 802.16j, whose objectives are looking into increasing the capacity and coverage of the cellular networks. This book focuses on recent progresses,  covering the related topics including scenarios of heterogeneous network deployment, interference management i

  19. Nanostructured cellular networks.

    Science.gov (United States)

    Moriarty, P; Taylor, M D R; Brust, M

    2002-12-01

    Au nanocrystals spin-coated onto silicon from toluene form cellular networks. A quantitative statistical crystallography analysis shows that intercellular correlations drive the networks far from statistical equilibrium. Spin-coating from hexane does not produce cellular structure, yet a strong correlation is retained in the positions of nanocrystal aggregates. Mechanisms based on Marangoni convection alone cannot account for the variety of patterns observed, and we argue that spinodal decomposition plays an important role in foam formation.

  20. How to Maximize User Satisfaction Degree in Multi-service IP Networks

    CERN Document Server

    Nguyen, Huy; Choi, Deokjai

    2010-01-01

    Bandwidth allocation is a fundamental problem in communication networks. With current network moving towards the Future Internet model, the problem is further intensified as network traffic demanding far from exceeds network bandwidth capability. Maintaining a certain user satisfaction degree therefore becomes a challenge research topic. In this paper, we deal with the problem by proposing BASMIN, a novel bandwidth allocation scheme that aims to maximize network user's happiness. We also defined a new metric for evaluating network user satisfaction degree: network worth. A three-step evaluation process is then conducted to compare BASMIN efficiency with other three popular bandwidth allocation schemes. Throughout the tests, we experienced BASMIN's advantages over the others; we even found out that one of the most widely used bandwidth allocation schemes, in fact, is not effective at all.

  1. An Adaptive and Multi-Service Routing Protocol for Wireless Sensor Networks

    CERN Document Server

    Sen, Jaydip

    2011-01-01

    Wireless Sensor Networks (WSNs) are highly distributed networks consisting of a large number of tiny, low-cost, light-weight wireless nodes deployed to monitor an environment or a system. Each node in a WSN consists of three subsystems: the sensor subsystem which senses the environment, the processing subsystem which performs local computations on the sensed data, and the communication subsystem which is responsible for message exchange with neighboring sensor nodes. While an individual sensor node has limited sensing region, processing power, and energy, networking a large number of sensor nodes give rise to a robust, reliable, and accurate sensor network covering a wide region. Thus, routing in WSNs is a very important issue. This paper presents a query-based routing protocol for a WSN that provides different levels of Quality of Service (QoS): energy-efficiency, reliability, low latency and fault-tolerance-under different application scenarios. The algorithm has low computational complexity but can dynamic...

  2. Admission Control for Multiservices Traffic in Hierarchical Mobile IPv6 Networks by Using Fuzzy Inference System

    Directory of Open Access Journals (Sweden)

    Jung-Shyr Wu

    2012-01-01

    Full Text Available CAC (Call Admission Control plays a significant role in providing QoS (Quality of Service in mobile wireless networks. In addition to much research that focuses on modified Mobile IP to get better efficient handover performance, CAC should be introduced to Mobile IP-based network to guarantee the QoS for users. In this paper, we propose a CAC scheme which incorporates multiple traffic types and adjusts the admission threshold dynamically using fuzzy control logic to achieve better usage of resources. The method can provide QoS in Mobile IPv6 networks with few modifications on MAP (Mobility Anchor Point functionality and slight change in BU (Binding Update message formats. According to the simulation results, the proposed scheme presents good performance of voice and video traffic at the expenses of poor performance on data traffic. It is evident that these CAC schemes can reduce the probability of the handoff dropping and the cell overload and limit the probability of the new call blocking.

  3. Gigabit-converged wired and wireless networks for simultaneous multi-services transmission

    Institute of Scientific and Technical Information of China (English)

    Liwei Yang; Xiaoping Zheng; Xin Zhou; He Wen; Hanyi Zhang; Yili Guo; Bingkun Zhou

    2011-01-01

    A novel architecture of converged radioover-fiber (RoF) and wavelength division multiplexed passive optical network (WDM-PON) system, namely FLoF-WDM-PON, is demonstrated. 20-GHz 1-Gb/s radio frequency (RF) signals and 1-Gb/s baseband (BB) signals are simultaneously generated and transmitted using optical carrier suppression (OCS) modulation techniques. The proposed scheme is compatible with the conventional RoF and PON system. 25-km single-mode fiber (SMF) transmission is successfully achieved.%A novel architecture of converged radio-over-fiber (RoF) and wavelength division multiplexed passive optical network (WDM-PON) system,namely RoF-WDM-PON,is demonstrated.20-GHz 1-Gb/s radio frequency (RF) signals and 1-Gb/s baseband (BB) signals are simultaneously generated and transmitted using optical carrier suppression (OCS) modulation techniques.The proposed scheme is compatible with the conventional RoF and PON system.25-km single-mode fiber (SMF) transmission is successfully achieved.

  4. Environment Aware Cellular Networks

    KAUST Repository

    Ghazzai, Hakim

    2015-02-01

    The unprecedented rise of mobile user demand over the years have led to an enormous growth of the energy consumption of wireless networks as well as the greenhouse gas emissions which are estimated currently to be around 70 million tons per year. This significant growth of energy consumption impels network companies to pay huge bills which represent around half of their operating expenditures. Therefore, many service providers, including mobile operators, are looking for new and modern green solutions to help reduce their expenses as well as the level of their CO2 emissions. Base stations are the most power greedy element in cellular networks: they drain around 80% of the total network energy consumption even during low traffic periods. Thus, there is a growing need to develop more energy-efficient techniques to enhance the green performance of future 4G/5G cellular networks. Due to the problem of traffic load fluctuations in cellular networks during different periods of the day and between different areas (shopping or business districts and residential areas), the base station sleeping strategy has been one of the main popular research topics in green communications. In this presentation, we present several practical green techniques that provide significant gains for mobile operators. Indeed, combined with the base station sleeping strategy, these techniques achieve not only a minimization of the fossil fuel consumption but also an enhancement of mobile operator profits. We start with an optimized cell planning method that considers varying spatial and temporal user densities. We then use the optimal transport theory in order to define the cell boundaries such that the network total transmit power is reduced. Afterwards, we exploit the features of the modern electrical grid, the smart grid, as a new tool of power management for cellular networks and we optimize the energy procurement from multiple energy retailers characterized by different prices and pollutant

  5. Multiservice Vertical Handoff Decision Algorithms

    Directory of Open Access Journals (Sweden)

    Zhu Fang

    2006-01-01

    Full Text Available Future wireless networks must be able to coordinate services within a diverse-network environment. One of the challenging problems for coordination is vertical handoff, which is the decision for a mobile node to handoff between different types of networks. While traditional handoff is based on received signal strength comparisons, vertical handoff must evaluate additional factors, such as monetary cost, offered services, network conditions, and user preferences. In this paper, several optimizations are proposed for the execution of vertical handoff decision algorithms, with the goal of maximizing the quality of service experienced by each user. First, the concept of policy-based handoffs is discussed. Then, a multiservice vertical handoff decision algorithm (MUSE-VDA and cost function are introduced to judge target networks based on a variety of user- and network-valued metrics. Finally, a performance analysis demonstrates that significant gains in the ability to satisfy user requests for multiple simultaneous services and a more efficient use of resources can be achieved from the MUSE-VDA optimizations.

  6. Multiuser Cellular Network

    CERN Document Server

    Bao, Yi; Chen, Ming

    2011-01-01

    Modern radio communication is faced with a problem about how to distribute restricted frequency to users in a certain space. Since our task is to minimize the number of repeaters, a natural idea is enlarging coverage area. However, coverage has restrictions. First, service area has to be divided economically as repeater's coverage is limited. In this paper, our fundamental method is to adopt seamless cellular network division. Second, underlying physics content in frequency distribution problem is interference between two close frequencies. Consequently, we choose a proper frequency width of 0.1MHz and a relevantly reliable setting to apply one frequency several times. We make a few general assumptions to simplify real situation. For instance, immobile users yield to homogenous distribution; repeaters can receive and transmit information in any given frequency in duplex operation; coverage is mainly decided by antenna height. Two models are built up to solve 1000 users and 10000 users situations respectively....

  7. Energy Landscape of Cellular Networks

    Science.gov (United States)

    Wang, Jin

    2008-03-01

    Cellular Networks are in general quite robust and perform their biological functions against the environmental perturbations. Progresses have been made from experimental global screenings, topological and engineering studies. However, there are so far few studies of why the network should be robust and perform biological functions from global physical perspectives. In this work, we will explore the global properties of the network from physical perspectives. The aim of this work is to develop a conceptual framework and quantitative physical methods to study the global nature of the cellular network. The main conclusion of this presentation is that we uncovered the underlying energy landscape for several small cellular networks such as MAPK signal transduction network and gene regulatory networks, from the experimentally measured or inferred inherent chemical reaction rates. The underlying dynamics of these networks can show bi-stable as well as oscillatory behavior. The global shapes of the energy landscapes of the underlying cellular networks we have studied are robust against perturbations of the kinetic rates and environmental disturbances through noise. We derived a quantitative criterion for robustness of the network function from the underlying landscape. It provides a natural explanation of the robustness and stability of the network for performing biological functions. We believe the robust landscape is a global universal property for cellular networks. We believe the robust landscape is a quantitative realization of Darwinian principle of natural selection at the cellular network level. It may provide a novel algorithm for optimizing the network connections, which is crucial for the cellular network design and synthetic biology. Our approach is general and can be applied to other cellular networks.

  8. MIMO Communication for Cellular Networks

    CERN Document Server

    Huang, Howard; Venkatesan, Sivarama

    2012-01-01

    As the theoretical foundations of multiple-antenna techniques evolve and as these multiple-input multiple-output (MIMO) techniques become essential for providing high data rates in wireless systems, there is a growing need to understand the performance limits of MIMO in practical networks. To address this need, MIMO Communication for Cellular Networks presents a systematic description of MIMO technology classes and a framework for MIMO system design that takes into account the essential physical-layer features of practical cellular networks. In contrast to works that focus on the theoretical performance of abstract MIMO channels, MIMO Communication for Cellular Networks emphasizes the practical performance of realistic MIMO systems. A unified set of system simulation results highlights relative performance gains of different MIMO techniques and provides insights into how best to use multiple antennas in cellular networks under various conditions. MIMO Communication for Cellular Networks describes single-user,...

  9. Optical Access Multiservice Architecture with Support to Smart Grid

    DEFF Research Database (Denmark)

    Gómez-Martínez, Alejandro; Amaya-Fernández, Ferney; Hincapié, Roberto

    2013-01-01

    The increasing demand of fixed and mobile applications, and considering that smart grid imposes new requirements to the access networks, in this paper we present an optical access architecture to support home multiservice including smart grid applications. We propose a migration path based in a WDM...

  10. 5G Ultra-Dense Cellular Networks

    OpenAIRE

    Ge, Xiaohu; Tu, Song; Mao, Guoqiang; Wang, Cheng-xiang; Han, Tao

    2015-01-01

    Traditional ultra-dense wireless networks are recommended as a complement for cellular networks and are deployed in partial areas, such as hotspot and indoor scenarios. Based on the massive multiple-input multi-output (MIMO) antennas and the millimeter wavecommunication technologies, the 5G ultra-dense cellular network is proposed to deploy in overall cellular scenarios. Moreover, a distribution network architecture is presented for 5G ultra-dense cellular networks. Furthermore, the backhaul ...

  11. Multi-Service Coverage Analysis for CDMA Planning

    Institute of Scientific and Technical Information of China (English)

    SUN Peng; LIU Zhi-ping; QIU Hong; YANG Da-cheng

    2004-01-01

    In CDMA network planning, it's important to understand the characteristics of multi-services. A novel method for analyzing the coverage of mixed voice and packet data traffics is presented in this paper. Based upon GIS and Monte-Carlo simulation method, this method can provide more precise but less time-consuming analysis result than before.A practical analysis case using real geographic information and network parameters is applied to verify its performance and find some useful solutions. Simulation results show that this coverage analysis method can provide helpful solution for the radio networks planning.

  12. Interworking of wireless lans and cellular networks

    CERN Document Server

    Song, Wei

    2014-01-01

    The next-generation of wireless communications are envisioned to be supported by heterogeneous networks by using various wireless access technologies. The popular cellular networks and wireless local area networks (WLANs) present perfectly complementary characteristics in terms of service capacity, mobility support, and quality-of-service (QoS) provisioning. The cellular/WLAN interworking is an effective way to promote the evolution of wireless networks. Interworking of Wireless LANs and Cellular Networks focuses on three aspects, namely access selection, call admission control and load sharing to investigate heterogeneous interworking for cellular/WLAN integrated networks. It not only reveals important observations but also offers useful tools for performance evaluation. The unique traffic and network characteristics are exploited to enhance interworking effectiveness. Theoretical analysis and simulation validation demonstrate benefits of cellular/WLAN interworking in real networks. Last but not the least,...

  13. Software-Defined Cellular Mobile Network Solutions

    Institute of Scientific and Technical Information of China (English)

    Jiandong Li; Peng Liu; Hongyan Li

    2014-01-01

    The emergency relating to software-defined networking (SDN), especially in terms of the prototype associated with OpenFlow, pro-vides new possibilities for innovating on network design. Researchers have started to extend SDN to cellular networks. Such new programmable architecture is beneficial to the evolution of mobile networks and allows operators to provide better services. The typical cellular network comprises radio access network (RAN) and core network (CN); hence, the technique roadmap diverges in two ways. In this paper, we investigate SoftRAN, the latest SDN solution for RAN, and SoftCell and MobileFlow, the latest solu-tions for CN. We also define a series of control functions for CROWD. Unlike in the other literature, we emphasize only software-defined cellular network solutions and specifications in order to provide possible research directions.

  14. 多业务网络中一种新队列调度算法的研究%A new queuing scheduling algorithm for multi-service network

    Institute of Scientific and Technical Information of China (English)

    张春风; 钱学荣

    2015-01-01

    In this paper, an improved algorithm was proposed based on the traditional weighted round robin algorithm, the strict priority scheduling algorithm and the token bucket mechanism. In coexistence of multi-service network , this algorithm can guarantee the QoS (Quality of Service) requirements of different types of traffic. Mean while, when the traffic changes, the algorithm can adjust the bandwidth corresponding service dynamically, and does not affect the high priority queue. Simulation results show that the algorithm can adapt to the changes in the network within a certain range, and the algorithm can alleviate the problem of packet loss caused by burst traffic effectively, improving network performance greatly.%在传统加权轮询调度算法和严格优先级调度算法的基础上,加入令牌桶机制,实现了一种改进算法。在多业务并存网络中,该算法能够对不同等级的业务实现不同的 QoS (服务质量),同时,在业务流量发生变化时,能够动态调整相应业务的带宽,且不会对高优先级队列造成影响。仿真实验表明,该算法可以在一定范围内适应网络的变化,有效缓解了突发流量所造成的报文丢包问题,大大提高了网络性能。

  15. Virtual networks in the cellular domain

    OpenAIRE

    Söderström, Gustav

    2003-01-01

     Data connectivity between cellular devices can be achieved in different ways. It is possible to enable full IPconnectivity in the cellular networks. However this connectivity is combined with a lot of issues such as security problems and the IPv4 address space being depleted. As a result of this many operators use Network Address Translation in their packet data networks, preventing users in different networks from being able to contact each other. Even if a transition to IPv6 takes place an...

  16. The multi service cable network along a natural gas network for urban distribution; Reseau cable multiservice associe a un reseau de gaz naturel pour la consommation publique

    Energy Technology Data Exchange (ETDEWEB)

    Markovic, D.; Krsmanovic, Z. [NIS-Energogas (Yugoslavia)

    2000-07-01

    The paper discusses parallel construction and development of natural gas and telecommunications projects in Europe, with an emphasis on the situation in FR Yugoslavia. Deregulation of postal services has created an opportunity for joint construction of multipurpose cable networks and gas distribution systems. Advantages are shown of such joint construction of gas pipeline and cable systems, and the strategy of further development of telecommunications and gas supply projects in FR Yugoslavia is presented. (authors)

  17. Overlaid Cellular and Mobile Ad Hoc Networks

    CERN Document Server

    Huang, Kaibin; Chen, Bin; Yang, Xia; Lau, Vincent K N

    2008-01-01

    In cellular systems using frequency division duplex, growing Internet services cause unbalance of uplink and downlink traffic, resulting in poor uplink spectrum utilization. Addressing this issue, this paper considers overlaying an ad hoc network onto a cellular uplink network for improving spectrum utilization and spatial reuse efficiency. Transmission capacities of the overlaid networks are analyzed, which are defined as the maximum densities of the ad hoc nodes and mobile users under an outage constraint. Using tools from stochastic geometry, the capacity tradeoff curves for the overlaid networks are shown to be linear. Deploying overlaid networks based on frequency separation is proved to achieve higher network capacities than that based on spatial separation. Furthermore, spatial diversity is shown to enhance network capacities.

  18. Optimal Band Allocation for Cognitive Cellular Networks

    CERN Document Server

    Liu, Tingting

    2011-01-01

    FCC new regulation for cognitive use of the TV white space spectrum provides a new means for improving traditional cellular network performance. But it also introduces a number of technical challenges. This letter studies one of the challenges, that is, given the significant differences in the propagation property and the transmit power limitations between the cellular band and the TV white space, how to jointly utilize both bands such that the benefit from the TV white space for improving cellular network performance is maximized. Both analytical and simulation results are provided.

  19. Evaluation of the Tellabs 1150 GPON multiservice access platform.

    Energy Technology Data Exchange (ETDEWEB)

    Brenkosh, Joseph Peter; Wolf, Jimmie V.

    2014-11-01

    For over two years, Sandia National Laboratories has been using a Gigabit Passive Optical Network (GPON) access layer for selected networks. The GPON equipment includes the Tellabs 1150 Multiservice Access Platform (MSAP) Optical Line Terminal (OLT), the Tellabs ONT709 and ONT709GP Optical Network Terminals (ONTs), and the Panorama PON Network Manager. In late 2013, the Tellabs equipment was updated to Software Release FP27.1_015130. Because a new software release has the potential to affect performance and functionality, it needed to be thoroughly tested. This report documents that testing. It also provides a comparison between the current release and the previous Software Release FP25.5.1_013274 that was being used.

  20. Evaluation of the Tellabs 1150 GPON multiservice access platform

    Energy Technology Data Exchange (ETDEWEB)

    Brenkosh, Joseph Peter [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Wolf, Jimmie V. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-11-01

    For over two years, Sandia National Laboratories has been using a Gigabit Passive Optical Network (GPON) access layer for selected networks. The GPON equipment includes the Tellabs 1150 Multiservice Access Platform (MSAP) Optical Line Terminal (OLT), the Tellabs ONT709 and ONT709GP Optical Network Terminals (ONTs), and the Panorama PON Network Manager. In late 2013, the Tellabs equipment was updated to Software Release FP27.1_015130. Because a new software release has the potential to affect performance and functionality, it needed to be thoroughly tested. This report documents that testing. It also provides a comparison between the current release and the previous Software Release FP25.5.1_013274 that was being used.

  1. Complexity, dynamic cellular network, and tumorigenesis.

    Science.gov (United States)

    Waliszewski, P

    1997-01-01

    A holistic approach to tumorigenesis is proposed. The main element of the model is the existence of dynamic cellular network. This network comprises a molecular and an energetistic structure of a cell connected through the multidirectional flow of information. The interactions within dynamic cellular network are complex, stochastic, nonlinear, and also involve quantum effects. From this non-reductionist perspective, neither tumorigenesis can be limited to the genetic aspect, nor the initial event must be of molecular nature, nor mutations and epigenetic factors are mutually exclusive, nor a link between cause and effect can be established. Due to complexity, an unstable stationary state of dynamic cellular network rather than a group of unrelated genes determines the phenotype of normal and transformed cells. This implies relativity of tumor suppressor genes and oncogenes. A bifurcation point is defined as an unstable state of dynamic cellular network leading to the other phenotype-stationary state. In particular, the bifurcation point may be determined by a change of expression of a single gene. Then, the gene is called bifurcation point gene. The unstable stationary state facilitates the chaotic dynamics. This may result in a fractal dimension of both normal and tumor tissues. The co-existence of chaotic dynamics and complexity is the essence of cellular processes and shapes differentiation, morphogenesis, and tumorigenesis. In consequence, tumorigenesis is a complex, unpredictable process driven by the interplay between self-organisation and selection.

  2. Interservice Availability of Multiservice Used Items.

    Science.gov (United States)

    1999-05-14

    t PIVT OF DISTRIBUTION STATEMENT A Approved for Public Releaseo r. Distribution Unlimited 19990817 034 INTERSERVICE AVAILABILTY OF MULTISERVICE USED...was initially cataloged or placed in the DoD supply system. As items matured, that is, as recurring item costs, usage rates, and technological

  3. Tension and robustness in multitasking cellular networks.

    Directory of Open Access Journals (Sweden)

    Jeffrey V Wong

    Full Text Available Cellular networks multitask by exhibiting distinct, context-dependent dynamics. However, network states (parameters that generate a particular dynamic are often sub-optimal for others, defining a source of "tension" between them. Though multitasking is pervasive, it is not clear where tension arises, what consequences it has, and how it is resolved. We developed a generic computational framework to examine the source and consequences of tension between pairs of dynamics exhibited by the well-studied RB-E2F switch regulating cell cycle entry. We found that tension arose from task-dependent shifts in parameters associated with network modules. Although parameter sets common to distinct dynamics did exist, tension reduced both their accessibility and resilience to perturbation, indicating a trade-off between "one-size-fits-all" solutions and robustness. With high tension, robustness can be preserved by dynamic shifting of modules, enabling the network to toggle between tasks, and by increasing network complexity, in this case by gene duplication. We propose that tension is a general constraint on the architecture and operation of multitasking biological networks. To this end, our work provides a framework to quantify the extent of tension between any network dynamics and how it affects network robustness. Such analysis would suggest new ways to interfere with network elements to elucidate the design principles of cellular networks.

  4. On noise limited cellular networks

    CERN Document Server

    Decreusefond, Laurent; Vu, Thanh-Tung

    2010-01-01

    This paper introduces a general theoretical framework to analyze noise limited networks. More precisely, we consider two homogenous Poisson point processes of base stations and users. General model of radio signal propagation and effect of fading are also considered. The main difference of our model with respect to other existing models is that a user connects to his best servers but not necessarily the closest one. We provide general formula for the outage probability. We study functionals related to the SNR as well as the sum of these functionals over all users per cell. For the latter, the expectation and bounds on the variance are obtained.

  5. Cognitive resource management for heterogeneous cellular networks

    CERN Document Server

    Liu, Yongkang

    2014-01-01

    This Springer Brief focuses on cognitive resource management in heterogeneous cellular networks (Het Net) with small cell deployment for the LTE-Advanced system. It introduces the Het Net features, presents practical approaches using cognitive radio technology in accommodating small cell data relay and optimizing resource allocation and examines the effectiveness of resource management among small cells given limited coordination bandwidth and wireless channel uncertainty. The authors introduce different network characteristics of small cell, investigate the mesh of small cell access points in

  6. Wireless traffic steering for green cellular networks

    CERN Document Server

    Zhang, Shan; Zhou, Sheng; Niu, Zhisheng; Shen, Xuemin (Sherman)

    2016-01-01

    This book introduces wireless traffic steering as a paradigm to realize green communication in multi-tier heterogeneous cellular networks. By matching network resources and dynamic mobile traffic demand, traffic steering helps to reduce on-grid power consumption with on-demand services provided. This book reviews existing solutions from the perspectives of energy consumption reduction and renewable energy harvesting. Specifically, it explains how traffic steering can improve energy efficiency through intelligent traffic-resource matching. Several promising traffic steering approaches for dynamic network planning and renewable energy demand-supply balancing are discussed. This book presents an energy-aware traffic steering method for networks with energy harvesting, which optimizes the traffic allocated to each cell based on the renewable energy status. Renewable energy demand-supply balancing is a key factor in energy dynamics, aimed at enhancing renewable energy sustainability to reduce on-grid energy consum...

  7. Virtualized cognitive network architecture for 5G cellular networks

    KAUST Repository

    Elsawy, Hesham

    2015-07-17

    Cellular networks have preserved an application agnostic and base station (BS) centric architecture1 for decades. Network functionalities (e.g. user association) are decided and performed regardless of the underlying application (e.g. automation, tactile Internet, online gaming, multimedia). Such an ossified architecture imposes several hurdles against achieving the ambitious metrics of next generation cellular systems. This article first highlights the features and drawbacks of such architectural ossification. Then the article proposes a virtualized and cognitive network architecture, wherein network functionalities are implemented via software instances in the cloud, and the underlying architecture can adapt to the application of interest as well as to changes in channels and traffic conditions. The adaptation is done in terms of the network topology by manipulating connectivities and steering traffic via different paths, so as to attain the applications\\' requirements and network design objectives. The article presents cognitive strategies to implement some of the classical network functionalities, along with their related implementation challenges. The article further presents a case study illustrating the performance improvement of the proposed architecture as compared to conventional cellular networks, both in terms of outage probability and handover rate.

  8. Mobile Node Localization in Cellular Networks

    Directory of Open Access Journals (Sweden)

    Yasir Malik

    2012-01-01

    Full Text Available Location information is the major component in location based applications. This information is used in different safety and service oriented applications to provide users with services according to their Geolocation. There are many approaches to locate mobile nodes in indoor and outdoor environments. In thispaper, we are interested in outdoor localization particularly in cellular networks of mobile nodes andpresented a localization method based on cell and user location information. Our localization method is based on hello message delay (sending and receiving time and coordinate information of Base Transceiver Station (BTSs. To validate our method across cellular network, we implemented and simulated our method in two scenarios i.e. maintaining database of base stations in centralize and distributed system. Simulation results show the effectiveness of our approach and its implementation applicability in telecommunication systems.

  9. WD40 proteins propel cellular networks.

    Science.gov (United States)

    Stirnimann, Christian U; Petsalaki, Evangelia; Russell, Robert B; Müller, Christoph W

    2010-10-01

    Recent findings indicate that WD40 domains play central roles in biological processes by acting as hubs in cellular networks; however, they have been studied less intensely than other common domains, such as the kinase, PDZ or SH3 domains. As suggested by various interactome studies, they are among the most promiscuous interactors. Structural studies suggest that this property stems from their ability, as scaffolds, to interact with diverse proteins, peptides or nucleic acids using multiple surfaces or modes of interaction. A general scaffolding role is supported by the fact that no WD40 domain has been found with intrinsic enzymatic activity despite often being part of large molecular machines. We discuss the WD40 domain distributions in protein networks and structures of WD40-containing assemblies to demonstrate their versatility in mediating critical cellular functions.

  10. Mobile node localization in cellular networks

    CERN Document Server

    Malik, Yasir; Abdulrazak, Bessam; Tariq, Usman; 10.5121/ijwmn.2011.3607

    2012-01-01

    Location information is the major component in location based applications. This information is used in different safety and service oriented applications to provide users with services according to their Geolocation. There are many approaches to locate mobile nodes in indoor and outdoor environments. In this paper, we are interested in outdoor localization particularly in cellular networks of mobile nodes and presented a localization method based on cell and user location information. Our localization method is based on hello message delay (sending and receiving time) and coordinate information of Base Transceiver Station (BTSs). To validate our method across cellular network, we implemented and simulated our method in two scenarios i.e. maintaining database of base stations in centralize and distributed system. Simulation results show the effectiveness of our approach and its implementation applicability in telecommunication systems.

  11. Developing a Resilient Green Cellular Network

    Science.gov (United States)

    2013-12-01

    Baser Stations, Cell Sites, Cell Towers COs Telecom Central Office COW Cellular on Wheels DHS Department of Homeland Security FCC Federal...nations that encounter frequent power outages for potential solutions to off set such dependency. India , the second largest mobile phone market...network, as noted in their National Telecom Policy-2012 (NTP).11 The policy posits how India can achieve its economic potential while providing socio

  12. Cellular recurrent deep network for image registration

    Science.gov (United States)

    Alam, M.; Vidyaratne, L.; Iftekharuddin, Khan M.

    2015-09-01

    Image registration using Artificial Neural Network (ANN) remains a challenging learning task. Registration can be posed as a two-step problem: parameter estimation and actual alignment/transformation using the estimated parameters. To date ANN based image registration techniques only perform the parameter estimation, while affine equations are used to perform the actual transformation. In this paper, we propose a novel deep ANN based image rigid registration that combines parameter estimation and transformation as a simultaneous learning task. Our previous work shows that a complex universal approximator known as Cellular Simultaneous Recurrent Network (CSRN) can successfully approximate affine transformations with known transformation parameters. This study introduces a deep ANN that combines a feed forward network with a CSRN to perform full rigid registration. Layer wise training is used to pre-train feed forward network for parameter estimation and followed by a CSRN for image transformation respectively. The deep network is then fine-tuned to perform the final registration task. Our result shows that the proposed deep ANN architecture achieves comparable registration accuracy to that of image affine transformation using CSRN with known parameters. We also demonstrate the efficacy of our novel deep architecture by a performance comparison with a deep clustered MLP.

  13. Empirical multiscale networks of cellular regulation.

    Directory of Open Access Journals (Sweden)

    Benjamin de Bivort

    2007-10-01

    Full Text Available Grouping genes by similarity of expression across multiple cellular conditions enables the identification of cellular modules. The known functions of genes enable the characterization of the aggregate biological functions of these modules. In this paper, we use a high-throughput approach to identify the effective mutual regulatory interactions between modules composed of mouse genes from the Alliance for Cell Signaling (AfCS murine B-lymphocyte database which tracks the response of approximately 15,000 genes following chemokine perturbation. This analysis reveals principles of cellular organization that we discuss along four conceptual axes. (1 Regulatory implications: the derived collection of influences between any two modules quantifies intuitive as well as unexpected regulatory interactions. (2 Behavior across scales: trends across global networks of varying resolution (composed of various numbers of modules reveal principles of assembly of high-level behaviors from smaller components. (3 Temporal behavior: tracking the mutual module influences over different time intervals provides features of regulation dynamics such as duration, persistence, and periodicity. (4 Gene Ontology correspondence: the association of modules to known biological roles of individual genes describes the organization of functions within coexpressed modules of various sizes. We present key specific results in each of these four areas, as well as derive general principles of cellular organization. At the coarsest scale, the entire transcriptional network contains five divisions: two divisions devoted to ATP production/biosynthesis and DNA replication that activate all other divisions, an "extracellular interaction" division that represses all other divisions, and two divisions (proliferation/differentiation and membrane infrastructure that activate and repress other divisions in specific ways consistent with cell cycle control.

  14. Call Admission Control in Mobile Cellular Networks

    CERN Document Server

    Ghosh, Sanchita

    2013-01-01

    Call Admission Control (CAC) and Dynamic Channel Assignments (DCA) are important decision-making problems in mobile cellular communication systems. Current research in mobile communication considers them as two independent problems, although the former greatly depends on the resulting free channels obtained as the outcome of the latter. This book provides a solution to the CAC problem, considering DCA as an integral part of decision-making for call admission. Further, current technical resources ignore movement issues of mobile stations and fluctuation in network load (incoming calls) in the control strategy used for call admission. In addition, the present techniques on call admission offers solution globally for the entire network, instead of considering the cells independently.      CAC here has been formulated by two alternative approaches. The first approach aimed at handling the uncertainty in the CAC problem by employing fuzzy comparators.  The second approach is concerned with formulation of CAC ...

  15. Green Cellular Networks: A Survey, Some Research Issues and Challenges

    CERN Document Server

    Hasan, Ziaul; Bhargava, Vijay K

    2011-01-01

    Energy efficiency in cellular networks is a growing concern for cellular operators to not only maintain profitability, but also to reduce the overall environment effects. This emerging trend of achieving energy efficiency in cellular networks is motivating the standardization authorities and network operators to continuously explore future technologies in order to bring improvements in the entire network infrastructure. In this article, we present a brief survey of methods to improve the power efficiency of cellular networks, explore some research issues and challenges and suggest some techniques to enable an energy efficient or "green" cellular network. Since base stations consume a maximum portion of the total energy used in a cellular system, we will first provide a comprehensive survey on techniques to obtain energy savings in base stations. Next, we discuss how heterogenous network deployment based on micro, pico and femto-cells can be used to achieve this goal. Since cognitive radio and cooperative rela...

  16. Power Control in Multi-Layer Cellular Networks

    CERN Document Server

    Davaslioglu, Kemal

    2012-01-01

    We investigate the possible performance gains of power control in multi-layer cellular systems where microcells and picocells are distributed within macrocells. Although multilayers in cellular networks help increase system capacity and coverage, and can reduce total energy consumption; they cause interference, reducing the performance of the network. Therefore, downlink transmit power levels of multi-layer hierarchical cellular networks need to be controlled in order to fully exploit their benefits. In this work, we present an analytical derivation to determine optimum power levels for two-layer cellular networks and generalize our solution to multi-layer cellular networks. We also simulate our results in a typical multi-layer network setup and observe significant power savings compared to single-layer cellular networks.

  17. Optimal flux patterns in cellular metabolic networks

    Energy Technology Data Exchange (ETDEWEB)

    Almaas, E

    2007-01-20

    The availability of whole-cell level metabolic networks of high quality has made it possible to develop a predictive understanding of bacterial metabolism. Using the optimization framework of flux balance analysis, I investigate metabolic response and activity patterns to variations in the availability of nutrient and chemical factors such as oxygen and ammonia by simulating 30,000 random cellular environments. The distribution of reaction fluxes is heavy-tailed for the bacteria H. pylori and E. coli, and the eukaryote S. cerevisiae. While the majority of flux balance investigations have relied on implementations of the simplex method, it is necessary to use interior-point optimization algorithms to adequately characterize the full range of activity patterns on metabolic networks. The interior-point activity pattern is bimodal for E. coli and S. cerevisiae, suggesting that most metabolic reaction are either in frequent use or are rarely active. The trimodal activity pattern of H. pylori indicates that a group of its metabolic reactions (20%) are active in approximately half of the simulated environments. Constructing the high-flux backbone of the network for every environment, there is a clear trend that the more frequently a reaction is active, the more likely it is a part of the backbone. Finally, I briefly discuss the predicted activity patterns of the central-carbon metabolic pathways for the sample of random environments.

  18. Cooperative Handover Management in Dense Cellular Networks

    KAUST Repository

    Arshad, Rabe

    2017-02-07

    Network densification has always been an important factor to cope with the ever increasing capacity demand. Deploying more base stations (BSs) improves the spatial frequency utilization, which increases the network capacity. However, such improvement comes at the expense of shrinking the BSs\\' footprints, which increases the handover (HO) rate and may diminish the foreseen capacity gains. In this paper, we propose a cooperative HO management scheme to mitigate the HO effect on throughput gains achieved via cellular network densification. The proposed HO scheme relies on skipping HO to the nearest BS at some instances along the user\\'s trajectory while enabling cooperative BS service during HO execution at other instances. To this end, we develop a mathematical model, via stochastic geometry, to quantify the performance of the proposed HO scheme in terms of coverage probability and user throughput. The results show that the proposed cooperative HO scheme outperforms the always best connected based association at high mobility. Also, the value of BS cooperation along with handover skipping is quantified with respect to the HO skipping only that has recently appeared in the literature. Particularly, the proposed cooperative HO scheme shows throughput gains of 12% to 27% and 17% on average, when compared to the always best connected and HO skipping only schemes at user velocity ranging from 80 km/h to 160 Km/h, respectively.

  19. Optimal flux patterns in cellular metabolic networks

    Energy Technology Data Exchange (ETDEWEB)

    Almaas, E

    2007-01-20

    The availability of whole-cell level metabolic networks of high quality has made it possible to develop a predictive understanding of bacterial metabolism. Using the optimization framework of flux balance analysis, I investigate metabolic response and activity patterns to variations in the availability of nutrient and chemical factors such as oxygen and ammonia by simulating 30,000 random cellular environments. The distribution of reaction fluxes is heavy-tailed for the bacteria H. pylori and E. coli, and the eukaryote S. cerevisiae. While the majority of flux balance investigations have relied on implementations of the simplex method, it is necessary to use interior-point optimization algorithms to adequately characterize the full range of activity patterns on metabolic networks. The interior-point activity pattern is bimodal for E. coli and S. cerevisiae, suggesting that most metabolic reaction are either in frequent use or are rarely active. The trimodal activity pattern of H. pylori indicates that a group of its metabolic reactions (20%) are active in approximately half of the simulated environments. Constructing the high-flux backbone of the network for every environment, there is a clear trend that the more frequently a reaction is active, the more likely it is a part of the backbone. Finally, I briefly discuss the predicted activity patterns of the central-carbon metabolic pathways for the sample of random environments.

  20. Wireless Fractal Ultra-Dense Cellular Networks.

    Science.gov (United States)

    Hao, Yixue; Chen, Min; Hu, Long; Song, Jeungeun; Volk, Mojca; Humar, Iztok

    2017-04-12

    With the ever-growing number of mobile devices, there is an explosive expansion in mobile data services. This represents a challenge for the traditional cellular network architecture to cope with the massive wireless traffic generated by mobile media applications. To meet this challenge, research is currently focused on the introduction of a small cell base station (BS) due to its low transmit power consumption and flexibility of deployment. However, due to a complex deployment environment and low transmit power of small cell BSs, the coverage boundary of small cell BSs will not have a traditional regular shape. Therefore, in this paper, we discuss the coverage boundary of an ultra-dense small cell network and give its main features: aeolotropy of path loss fading and fractal coverage boundary. Simple performance analysis is given, including coverage probability and transmission rate, etc., based on stochastic geometry theory and fractal theory. Finally, we present an application scene and discuss challenges in the ultra-dense small cell network.

  1. Spatial Dynamics of Multilayer Cellular Neural Networks

    Science.gov (United States)

    Wu, Shi-Liang; Hsu, Cheng-Hsiung

    2017-06-01

    The purpose of this work is to study the spatial dynamics of one-dimensional multilayer cellular neural networks. We first establish the existence of rightward and leftward spreading speeds of the model. Then we show that the spreading speeds coincide with the minimum wave speeds of the traveling wave fronts in the right and left directions. Moreover, we obtain the asymptotic behavior of the traveling wave fronts when the wave speeds are positive and greater than the spreading speeds. According to the asymptotic behavior and using various kinds of comparison theorems, some front-like entire solutions are constructed by combining the rightward and leftward traveling wave fronts with different speeds and a spatially homogeneous solution of the model. Finally, various qualitative features of such entire solutions are investigated.

  2. A Multi-Service Oriented Multiple-Access Scheme For M2M Support in Future LTE

    OpenAIRE

    Ksairi, Nassar; Tomasin, Stefano; Debbah, Mérouane

    2016-01-01

    We propose a novel multiple-access technique to overcome the shortcomings of the current proposals for the future releases of Long-Term Evolution (LTE). We provide a unified radio access system that efficiently and flexibly integrates both traditional cellular services and machine-to-machine (M2M) connections arising from Internet-of-Things (IoT) applications. The proposed solution, referred to as multi-service oriented multiple access (MOMA), is based on a) establishing separate classes of u...

  3. Travel Mode Detection Exploiting Cellular Network Data

    Directory of Open Access Journals (Sweden)

    Kalatian Arash

    2016-01-01

    Full Text Available There has been growing interest in exploiting cellular network data for transportation planning purposes in recent years. In this paper, we utilize these data for determining mode of travel in the city of Shiraz, Iran. Cellular data records -including location updates in 5minute time intervals- of 300,000 users from the city of Shiraz has been collected for 40 hours in three consecutive days in a cooperation with the major telecommunications service provider of the country. Depending on the density of mobile BTS’s in different zones of the city, the user location can be located within an average of 200 meters. Considering data filtering and smoothing, data preparation and converting them to comprehensible traces is a large portion of the work. A novel approach to identify stay locations is proposed and implemented in this paper. Origin-Destination matrices are then created based on trips detected, which shows acceptable consistency with current O-D matrices. Finally, Travel times for all trips of a user is estimated as the main attribute for clustering. Trips between same origin and destination zones are combined together in a group. Using K-means algorithm, records within each group are the portioned in two or three clusters, based on their travel speeds. Each cluster represents a certain mode of travel; walking, public transportation or driving a private car.

  4. Heterogeneous force network in 3D cellularized collagen networks

    Science.gov (United States)

    Liang, Long; Jones, Christopher; Chen, Shaohua; Sun, Bo; Jiao, Yang

    2016-12-01

    Collagen networks play an important role in coordinating and regulating collective cellular dynamics via a number of signaling pathways. Here, we investigate the transmission of forces generated by contractile cells in 3D collagen-I networks. Specifically, the graph (bond-node) representations of collagen networks with collagen concentrations of 1, 2 and 4 mg ml-1 are derived from confocal microscopy data and used to model the network microstructure. Cell contraction is modeled by applying correlated displacements at specific nodes of the network, representing the focal adhesion sites. A nonlinear elastic model is employed to characterize the mechanical behavior of individual fiber bundles including strain hardening during stretching and buckling under compression. A force-based relaxation method is employed to obtain equilibrium network configurations under cell contraction. We find that for all collagen concentrations, the majority of the forces are carried by a small number of heterogeneous force chains emitted from the contracting cells, which is qualitatively consistent with our experimental observations. The force chains consist of fiber segments that either possess a high degree of alignment before cell contraction or are aligned due to fiber reorientation induced by cell contraction. The decay of the forces along the force chains is significantly slower than the decay of radially averaged forces in the system, suggesting that the fibreous nature of biopolymer network structure can support long-range force transmission. The force chains emerge even at very small cell contractions, and the number of force chains increases with increasing cell contraction. At large cell contractions, the fibers close to the cell surface are in the nonlinear regime, and the nonlinear region is localized in a small neighborhood of the cell. In addition, the number of force chains increases with increasing collagen concentration, due to the larger number of focal adhesion sites

  5. Supporting performance and configuration management of GTE cellular networks

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Ming; Lafond, C.; Jakobson, G. [GTE Laboratories Inc., Waltham, MA (United States); Young, G. [GTE Mobilnet, Rosewell, GA (United States)

    1996-12-31

    GTE Laboratories, in cooperation with GTE Mobilnet, has developed and deployed PERFFEX (PERFormance Expert), an intelligent system for performance and configuration management of cellular networks. PERFEX assists cellular network performance and radio engineers in the analysis of large volumes of cellular network performance and configuration data. It helps them locate and determine the probable causes of performance problems, and provides intelligent suggestions about how to correct them. The system combines an expert cellular network performance tuning capability with a map-based graphical user interface, data visualization programs, and a set of special cellular engineering tools. PERFEX is in daily use at more than 25 GTE Mobile Switching Centers. Since the first deployment of the system in late 1993, PERFEX has become a major GTE cellular network performance optimization tool.

  6. Analytical Modeling of Uplink Cellular Networks

    CERN Document Server

    Novlan, Thomas D; Andrews, Jeffrey G

    2012-01-01

    Cellular uplink analysis has typically been undertaken by either a simple approach that lumps all interference into a single deterministic or random parameter in a Wyner-type model, or via complex system level simulations that often do not provide insight into why various trends are observed. This paper proposes a novel middle way that is both accurate and also results in easy-to-evaluate integral expressions based on the Laplace transform of the interference. We assume mobiles and base stations are randomly placed in the network with each mobile pairing up to its closest base station. The model requires two important changes compared to related recent work on the downlink. First, dependence is introduced between the user and base station point processes to make sure each base station serves a single mobile in the given resource block. Second, per-mobile power control is included, which further couples the locations of the mobiles and their receiving base stations. Nevertheless, we succeed in deriving the cov...

  7. Handover management in dense cellular networks: A stochastic geometry approach

    KAUST Repository

    Arshad, Rabe

    2016-07-26

    Cellular operators are continuously densifying their networks to cope with the ever-increasing capacity demand. Furthermore, an extreme densification phase for cellular networks is foreseen to fulfill the ambitious fifth generation (5G) performance requirements. Network densification improves spectrum utilization and network capacity by shrinking base stations\\' (BSs) footprints and reusing the same spectrum more frequently over the spatial domain. However, network densification also increases the handover (HO) rate, which may diminish the capacity gains for mobile users due to HO delays. In highly dense 5G cellular networks, HO delays may neutralize or even negate the gains offered by network densification. In this paper, we present an analytical paradigm, based on stochastic geometry, to quantify the effect of HO delay on the average user rate in cellular networks. To this end, we propose a flexible handover scheme to reduce HO delay in case of highly dense cellular networks. This scheme allows skipping the HO procedure with some BSs along users\\' trajectories. The performance evaluation and testing of this scheme for only single HO skipping shows considerable gains in many practical scenarios. © 2016 IEEE.

  8. Hybrid Spectral Efficient Cellular Network Deployment to Reduce RF Pollution

    National Research Council Canada - National Science Library

    Sumit Katiyar; R K Jain; N K Agrawal

    2012-01-01

    ... from these base stations may cause any health effect or hazard. Recently UP High Court in India ordered for removal of BTS towers from residential area, it has created panic among cellular communication network designers too...

  9. Boltzmann learning of parameters in cellular neural networks

    DEFF Research Database (Denmark)

    Hansen, Lars Kai

    1992-01-01

    The use of Bayesian methods to design cellular neural networks for signal processing tasks and the Boltzmann machine learning rule for parameter estimation is discussed. The learning rule can be used for models with hidden units, or for completely unsupervised learning. The latter is exemplified...... by unsupervised adaptation of an image segmentation cellular network. The learning rule is applied to adaptive segmentation of satellite imagery...

  10. Uncovering the footprints of malicious traffic in cellular data networks

    OpenAIRE

    Raghuramu, A; Zang, H; Chuah, CN

    2015-01-01

    © Springer International Publishing Switzerland 2015. In this paper, we present a comprehensive characterization of malicious traffic generated by mobile devices using Deep Packet Inspection (DPI) records and security event logs from a large US based cellular provider network. Our analysis reveals that 0.17% of mobile devices in the cellular network are affected by security threats. This proportion, while small, is orders of magnitude higher than the last reported (in 2013) infection rate of ...

  11. 5G and Cellular Networks in the Smart Grid

    DEFF Research Database (Denmark)

    Nielsen, Jimmy Jessen; Jorguseski, Ljupco; Zhang, Haibin

    2017-01-01

    Wireless cellular networks will help Distribution System Operators (DSOs) to achieve observability below the substation level, which is needed to ensure stable operation in the smart grid. Both existing and upcoming cellular technologies are considered as candidates for helping to enable the smart...... the challenges and possible solutions for ensuring end-to-end security in smart grid systems....

  12. Radio Channel Modelling for UAV Communication over Cellular Networks

    DEFF Research Database (Denmark)

    Amorim, Rafhael Medeiros de; Nguyen, Huan Cong; Mogensen, Preben Elgaard

    2017-01-01

    The main goal of this paper is to obtain models for path loss exponents and shadowing for the radio channel between airborne Unmanned Aerial Vehicles (UAVs) and cellular networks. In this pursuit, field measurements were conducted in live LTE networks at the 800 MHz frequency band, using...

  13. A new small-world network created by Cellular Automata

    Science.gov (United States)

    Ruan, Yuhong; Li, Anwei

    2016-08-01

    In this paper, we generate small-world networks by the Cellular Automaton based on starting with one-dimensional regular networks. Besides the common properties of small-world networks with small average shortest path length and large clustering coefficient, the small-world networks generated in this way have other properties: (i) The edges which are cut in the regular network can be controlled that whether the edges are reconnected or not, and (ii) the number of the edges of the small-world network model equals the number of the edges of the original regular network. In other words, the average degree of the small-world network model equals to the average degree of the original regular network.

  14. Energy management in wireless cellular and ad-hoc networks

    CERN Document Server

    Imran, Muhammad; Qaraqe, Khalid; Alouini, Mohamed-Slim; Vasilakos, Athanasios

    2016-01-01

    This book investigates energy management approaches for energy efficient or energy-centric system design and architecture and presents end-to-end energy management in the recent heterogeneous-type wireless network medium. It also considers energy management in wireless sensor and mesh networks by exploiting energy efficient transmission techniques and protocols. and explores energy management in emerging applications, services and engineering to be facilitated with 5G networks such as WBANs, VANETS and Cognitive networks. A special focus of the book is on the examination of the energy management practices in emerging wireless cellular and ad hoc networks. Considering the broad scope of energy management in wireless cellular and ad hoc networks, this book is organized into six sections covering range of Energy efficient systems and architectures; Energy efficient transmission and techniques; Energy efficient applications and services. .

  15. Error performance analysis in downlink cellular networks with interference management

    KAUST Repository

    Afify, Laila H.

    2015-05-01

    Modeling aggregate network interference in cellular networks has recently gained immense attention both in academia and industry. While stochastic geometry based models have succeeded to account for the cellular network geometry, they mostly abstract many important wireless communication system aspects (e.g., modulation techniques, signal recovery techniques). Recently, a novel stochastic geometry model, based on the Equivalent-in-Distribution (EiD) approach, succeeded to capture the aforementioned communication system aspects and extend the analysis to averaged error performance, however, on the expense of increasing the modeling complexity. Inspired by the EiD approach, the analysis developed in [1] takes into consideration the key system parameters, while providing a simple tractable analysis. In this paper, we extend this framework to study the effect of different interference management techniques in downlink cellular network. The accuracy of the proposed analysis is verified via Monte Carlo simulations.

  16. Personal communication in traditional cellular networks

    Science.gov (United States)

    Neuer, Ellwood I.

    1996-01-01

    The purpose of this paper is to describe the flow of calls through the mobile network as it applies to the operation of Basic and Enhanced Services. Included in the discussion is the overall network layout, the physical connections between the network entities, and the signaling protocols which allow the entities to be integrated. The specific functionality of the applications and services are not detailed as the specific implementation varies from vendor to vendor and from service provider to service provider. The Enhanced Services Platform is installed in a service providers network in order to offer mobile subscribers services and applications which would otherwise not be available. The service providers' objective is to increase revenue/subscriber, increase subscriber loyalty/decrease churn, and build competitive advantages through differentiation. The services provided on the Enhanced Services platform can be viewed as either Basic or Enhanced. For the purpose of this paper, Basic Services refers to Numeric Paging, Call Answering, and Voice Messaging while Enhanced Services refers to FAX Messaging, One Number Service, Voice Dialing and other Voice Recognition applications, Information Services including FAX on Demand, and Automated Call Routing.

  17. Green Cellular - Optimizing the Cellular Network for Minimal Emission from Mobile Stations

    CERN Document Server

    Ezri, Doron

    2009-01-01

    Wireless systems, which include cellular phones, have become an essential part of the modern life. However the mounting evidence that cellular radiation might adversely affect the health of its users, leads to a growing concern among authorities and the general public. Radiating antennas in the proximity of the user, such as antennas of mobile phones are of special interest for this matter. In this paper we suggest a new architecture for wireless networks, aiming at minimal emission from mobile stations, without any additional radiation sources. The new architecture, dubbed Green Cellular, abandons the classical transceiver base station design and suggests the augmentation of transceiver base stations with receive only devices. These devices, dubbed Green Antennas, are not aiming at coverage extension but rather at minimizing the emission from mobile stations. We discuss the implications of the Green Cellular architecture on 3G and 4G cellular technologies. We conclude by showing that employing the Green Cell...

  18. Microfabricated platforms for the study of neuronal and cellular networks

    Energy Technology Data Exchange (ETDEWEB)

    Berdondini, L; Generelli, S; Kraus, T; Guenat, O T; Koster, S; Linder, V; Koudelka-Hep, M; Rooij, N F de [SAMLAB, Institute of Microtechnology, University of Neuchatel (Switzerland)

    2006-04-01

    In this contribution we present the development of three microfabricated devices for the study of neuronal and cellular networks. Together, these devices form an attractive toolbox, which is useful to stimulate and record signals of both electrical and chemical nature. One approach consist of microelectrode arrays for the study of neuronal networks, and allow for the electrical stimulation of individual cells in the network, while the other electrodes of the array record the electrical activity of the remaining cells of the network. We also present the use of micropipettes that can measure the extra- and intracellular concentrations of ions in cells cultures. A third approach exploits the laminar flows in a microfluidic device, to deliver minute amounts of drug to some cells in a cellular network. These three illustrations show that microfabricated platforms are appealing analytical tools in the context of cell biology.

  19. Global stability analysis on a class of cellular neural networks

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Yi

    2001-01-01

    [1]Chua, L. O., Yang, L., Cellular neural networks: Theory, IEEE Trans. CAS, 1988, (10): 1257.[2]Chua, L. O., Yang, L., Cellular neural networks: Applications, IEEE Trans. CAS, 1988, (10): 1273.[3]Chua, L. O., Roska, T., The CNN paradigm, IEEE Trans. CAS-I, 1993, (3): 147.[4]Matsumoto, T. Chua, L. O., Suzuki, H., CNN cloning template: Connected component detector, IEEE Trans. CAS, 1990, (8): 633.[5]Cao, L, Sun, Y, Yu, J., A CNN-based signature verification system,Proc. ICONIP′95, Beijing, 1995, 913—916.[6]Roska, T., Chua, L. O., The CNN universal machine: An analogic array computer, IEEE Trans. CAS Ⅱ, 1993, (3): 163.[7]Chua, L. O., Roska, T., Stability of a class of nonreciprocal cellular neural networks, IEEE Trans. CAS, 1990, (3): 1520.[8]Roska, T., Wu, C. W., Balsi, M. Et al., Stability and dynamics of delay type general and cellular neural networks, IEEE Trans. CAS, 1992, (6): 487.[9]Roska, T., Wu, C. W., Chua, L. O., Stability of cellular neural networks with dominant nonlinear and delaytype templates, IEEE Trans. CAS, 1993, (4): 270.[10]Civalleri, P. P., On stability of cellular neural networks with delay, IEEE Trans. CAS-I, 1993, (3): 157.[11]Gilli, G., Stability of cellular neural network and delayed cellular neural networks with nonpositive templates and nonmonotonic output functions, IEEE Trans CAS-I, 1994, (8): 518.[12]Baldi, P., Atiya, A. F., How delays affect neural dynamics and learning, IEEE Trans. On Neural Networks, 1994, (4): 612.[13]Liao, X. X., Mathematic foundation of cellular neural networks (Ⅰ), Science in China, Ser. A, 1994, 37(9): 902.[14]Liao, X. X., Mathematic foundation of cellular neural networks (Ⅱ), Science in China, Ser. A, 1994, 37(9): 1037.[15]Zhang, Y., Global exponential stability and periodic solutions of delay Hopfild neural networks, International J. Sys. Sci., 1996, (2): 227.[16]Zhang Yi, Zhong, S. M., Li, Z. L., Periodic solutions and global

  20. Widrow-cellular neural network and optoelectronic implementation

    Science.gov (United States)

    Bal, Abdullah

    A new type of optoelectronic cellular neural network has been developed by providing the capability of coefficients adjusment of cellular neural network (CNN) using Widrow based perceptron learning algorithm. The new supervised cellular neural network is called Widrow-CNN. Despite the unsupervised CNN, the proposed learning algorithm allows to use the Widrow-CNN for various image processing applications easily. Also, the capability of CNN for image processing and feature extraction has been improved using basic joint transform correlation architecture. This hardware application presents high speed processing capability compared to digital applications. The optoelectronic Widrow-CNN has been tested for classic CNN feature extraction problems. It yields the best results even in case of hard feature extraction problems such as diagonal line detection and vertical line determination.

  1. Green Cellular Network Deployment To Reduce RF Pollution

    CERN Document Server

    Katiyar, Sumit; Agrawal, N K

    2012-01-01

    As the mobile telecommunication systems are growing tremendously all over the world, the numbers of handheld and base stations are also rapidly growing and it became very popular to see these base stations distributed everywhere in the neighborhood and on roof tops which has caused a considerable amount of panic to the public in Palestine concerning wither the radiated electromagnetic fields from these base stations may cause any health effect or hazard. Recently UP High Court in India ordered for removal of BTS towers from residential area, it has created panic among cellular communication network designers too. Green cellular networks could be a solution for the above problem. This paper deals with green cellular networks with the help of multi-layer overlaid hierarchical structure (macro / micro / pico / femto cells). Macrocell for area coverage, micro for pedestrian and a slow moving traffic while pico for indoor use and femto for individual high capacity users. This could be the answer of the problem of ...

  2. Cellular and network mechanisms of electrographic seizures

    Science.gov (United States)

    Bazhenov, Maxim; Timofeev, Igor; Fröhlich, Flavio; Sejnowski, Terrence J.

    2008-01-01

    Epileptic seizures constitute a complex multiscale phenomenon that is characterized by synchronized hyperexcitation of neurons in neuronal networks. Recent progress in understanding pathological seizure dynamics provides crucial insights into underlying mechanisms and possible new avenues for the development of novel treatment modalities. Here we review some recent work that combines in vivo experiments and computational modeling to unravel the pathophysiology of seizures of cortical origin. We particularly focus on how activity-dependent changes in extracellular potassium concentration affects the intrinsic dynamics of neurons involved in cortical seizures characterized by spike/wave complexes and fast runs. PMID:19190736

  3. Optimising base station location for UMTS cellular networks

    Science.gov (United States)

    Kalata, G.; Pozniak-Koszalka, I.; Koszalka, L.; Kasprzak, A.

    2014-12-01

    Rapid development of universal mobile telecommunication systems put demands on tools for assisting planning of cellular network infrastructure. The tools need to focus on critical issues in modern cellular networks and techniques used for previous generation system no longer serve useful. In this paper, an algorithm based on Branch & Bound approach is proposed for solving base station location problem, covering interference levels, traffic demands and power control mechanism. The efficiency of the algorithm is evaluated with respect to existing approaches for solving this problem - using the designed and implemented experimentation system.

  4. Template learning of cellular neural network using genetic programming.

    Science.gov (United States)

    Radwan, Elsayed; Tazaki, Eiichiro

    2004-08-01

    A new learning algorithm for space invariant Uncoupled Cellular Neural Network is introduced. Learning is formulated as an optimization problem. Genetic Programming has been selected for creating new knowledge because they allow the system to find new rules both near to good ones and far from them, looking for unknown good control actions. According to the lattice Cellular Neural Network architecture, Genetic Programming will be used in deriving the Cloning Template. Exploration of any stable domain is possible by the current approach. Details of the algorithm are discussed and several application results are shown.

  5. Modeling Integrated Cellular Machinery Using Hybrid Petri-Boolean Networks

    Science.gov (United States)

    Berestovsky, Natalie; Zhou, Wanding; Nagrath, Deepak; Nakhleh, Luay

    2013-01-01

    The behavior and phenotypic changes of cells are governed by a cellular circuitry that represents a set of biochemical reactions. Based on biological functions, this circuitry is divided into three types of networks, each encoding for a major biological process: signal transduction, transcription regulation, and metabolism. This division has generally enabled taming computational complexity dealing with the entire system, allowed for using modeling techniques that are specific to each of the components, and achieved separation of the different time scales at which reactions in each of the three networks occur. Nonetheless, with this division comes loss of information and power needed to elucidate certain cellular phenomena. Within the cell, these three types of networks work in tandem, and each produces signals and/or substances that are used by the others to process information and operate normally. Therefore, computational techniques for modeling integrated cellular machinery are needed. In this work, we propose an integrated hybrid model (IHM) that combines Petri nets and Boolean networks to model integrated cellular networks. Coupled with a stochastic simulation mechanism, the model simulates the dynamics of the integrated network, and can be perturbed to generate testable hypotheses. Our model is qualitative and is mostly built upon knowledge from the literature and requires fine-tuning of very few parameters. We validated our model on two systems: the transcriptional regulation of glucose metabolism in human cells, and cellular osmoregulation in S. cerevisiae. The model produced results that are in very good agreement with experimental data, and produces valid hypotheses. The abstract nature of our model and the ease of its construction makes it a very good candidate for modeling integrated networks from qualitative data. The results it produces can guide the practitioner to zoom into components and interconnections and investigate them using such more

  6. Modeling integrated cellular machinery using hybrid Petri-Boolean networks.

    Directory of Open Access Journals (Sweden)

    Natalie Berestovsky

    Full Text Available The behavior and phenotypic changes of cells are governed by a cellular circuitry that represents a set of biochemical reactions. Based on biological functions, this circuitry is divided into three types of networks, each encoding for a major biological process: signal transduction, transcription regulation, and metabolism. This division has generally enabled taming computational complexity dealing with the entire system, allowed for using modeling techniques that are specific to each of the components, and achieved separation of the different time scales at which reactions in each of the three networks occur. Nonetheless, with this division comes loss of information and power needed to elucidate certain cellular phenomena. Within the cell, these three types of networks work in tandem, and each produces signals and/or substances that are used by the others to process information and operate normally. Therefore, computational techniques for modeling integrated cellular machinery are needed. In this work, we propose an integrated hybrid model (IHM that combines Petri nets and Boolean networks to model integrated cellular networks. Coupled with a stochastic simulation mechanism, the model simulates the dynamics of the integrated network, and can be perturbed to generate testable hypotheses. Our model is qualitative and is mostly built upon knowledge from the literature and requires fine-tuning of very few parameters. We validated our model on two systems: the transcriptional regulation of glucose metabolism in human cells, and cellular osmoregulation in S. cerevisiae. The model produced results that are in very good agreement with experimental data, and produces valid hypotheses. The abstract nature of our model and the ease of its construction makes it a very good candidate for modeling integrated networks from qualitative data. The results it produces can guide the practitioner to zoom into components and interconnections and investigate them

  7. Modeling integrated cellular machinery using hybrid Petri-Boolean networks.

    Directory of Open Access Journals (Sweden)

    Natalie Berestovsky

    Full Text Available The behavior and phenotypic changes of cells are governed by a cellular circuitry that represents a set of biochemical reactions. Based on biological functions, this circuitry is divided into three types of networks, each encoding for a major biological process: signal transduction, transcription regulation, and metabolism. This division has generally enabled taming computational complexity dealing with the entire system, allowed for using modeling techniques that are specific to each of the components, and achieved separation of the different time scales at which reactions in each of the three networks occur. Nonetheless, with this division comes loss of information and power needed to elucidate certain cellular phenomena. Within the cell, these three types of networks work in tandem, and each produces signals and/or substances that are used by the others to process information and operate normally. Therefore, computational techniques for modeling integrated cellular machinery are needed. In this work, we propose an integrated hybrid model (IHM that combines Petri nets and Boolean networks to model integrated cellular networks. Coupled with a stochastic simulation mechanism, the model simulates the dynamics of the integrated network, and can be perturbed to generate testable hypotheses. Our model is qualitative and is mostly built upon knowledge from the literature and requires fine-tuning of very few parameters. We validated our model on two systems: the transcriptional regulation of glucose metabolism in human cells, and cellular osmoregulation in S. cerevisiae. The model produced results that are in very good agreement with experimental data, and produces valid hypotheses. The abstract nature of our model and the ease of its construction makes it a very good candidate for modeling integrated networks from qualitative data. The results it produces can guide the practitioner to zoom into components and interconnections and investigate them

  8. Cellular neural networks for the stereo matching problem

    Energy Technology Data Exchange (ETDEWEB)

    Taraglio, S. [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dipt. Innovazione; Zanela, A. [Rome Univ. `La Sapienza` (Italy). Dipt. di Fisica

    1997-03-01

    The applicability of the Cellular Neural Network (CNN) paradigm to the problem of recovering information on the tridimensional structure of the environment is investigated. The approach proposed is the stereo matching of video images. The starting point of this work is the Zhou-Chellappa neural network implementation for the same problem. The CNN based system we present here yields the same results as the previous approach, but without the many existing drawbacks.

  9. Cellular neural networks for the stereo matching problem

    Energy Technology Data Exchange (ETDEWEB)

    Taraglio, S. [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dipt. Innovazione; Zanela, A. [Rome Univ. `La Sapienza` (Italy). Dipt. di Fisica

    1997-03-01

    The applicability of the Cellular Neural Network (CNN) paradigm to the problem of recovering information on the tridimensional structure of the environment is investigated. The approach proposed is the stereo matching of video images. The starting point of this work is the Zhou-Chellappa neural network implementation for the same problem. The CNN based system we present here yields the same results as the previous approach, but without the many existing drawbacks.

  10. Control of Cellular Structural Networks Through Unstructured Protein Domains

    Science.gov (United States)

    2016-07-01

    structural and mechanical networks in cells. The research plan seeks to determine the role of molecular­scale steric forces on the assembly, mechanics...Distribution Unlimited UU UU UU UU 01-07-2016 1-Oct-2009 30-Sep-2015 Final Report: WHITEPAPER; Research Area 8; Control of cellular structural networks ...any other aspect of this collection of information, including suggesstions for reducing this burden, to Washington Headquarters Services , Directorate

  11. Social Data Offloading in D2D-Enhanced Cellular Networks by Network Formation Games

    OpenAIRE

    Wang, Tianyu; Sun, Yue; Song, Lingyang; Han, Zhu

    2015-01-01

    Recently, cellular networks are severely overloaded by social-based services, such as YouTube, Facebook and Twitter, in which thousands of clients subscribe a common content provider (e.g., a popular singer) and download his/her content updates all the time. Offloading such traffic through complementary networks, such as a delay tolerant network formed by device-to-device (D2D) communications between mobile subscribers, is a promising solution to reduce the cellular burdens. In the existing s...

  12. Pathloss Measurements and Modeling for UAVs Connected to Cellular Networks

    DEFF Research Database (Denmark)

    Amorim, Rafhael Medeiros de; Kovács, István; Sørensen, Troels Bundgaard

    2017-01-01

    This paper assess field measurements, as part of the investigation of the suitability of cellular networks for providing connectivity to UAVs (unmanned aerial vehicles). Evaluation is done by means of field measurements obtained in a rural environment in Denmark with an airbone UAV...

  13. Global asymptotic stability of cellular neural networks with multiple delays

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Global asymptotic stability (GAS) is discussed for cellular neural networks (CNN) with multiple time delays. Several criteria are proposed to ascertain the uniqueness and global asymptotic stability of the equilibrium point for the CNN with delays. These criteria can eliminate the difference between the neuronal excitatory and inhibitory effects. Two examples are presented to demonstrate the effectiveness of the criteria.

  14. Interference Alignment for Partially Connected MIMO Cellular Networks

    CERN Document Server

    Ruan, Liangzhong

    2012-01-01

    In this paper, we propose an iterative interference alignment (IA) algorithm for MIMO cellular networks with partial connectivity, which is induced by heterogeneous path losses and spatial correlation. Such systems impose several key technical challenges in the IA algorithm design, namely the overlapping between the direct and interfering links due to the MIMO cellular topology as well as how to exploit the partial connectivity. We shall address these challenges and propose a three stage IA algorithm. As illustration, we analyze the achievable degree of freedom (DoF) of the proposed algorithm for a symmetric partially connected MIMO cellular network. We show that there is significant DoF gain compared with conventional IA algorithms due to partial connectivity. The derived DoF bound is also backward compatible with that achieved on fully connected K-pair MIMO interference channels.

  15. Gateway Deployment optimization in Cellular Wi-Fi Mesh Networks

    Directory of Open Access Journals (Sweden)

    Rajesh Prasad

    2006-07-01

    Full Text Available With the standardization of IEEE 802.11, there has been an explosive growth of wireless local area networks (WLAN. Recently, this cost effective technology is being developed aggressively for establishing metro-scale “cellular Wi-Fi” network to support seamless Internet access in the urban area. We envision a large scale WLAN system in the future where Access Points (APs will be scattered over an entire city enabling people to use their mobile devices ubiquitously. The problem addressed in this paper involves finding the minimum number of gateways and their optimal placement so as to minimize the network installation costs while maintaining reliability, flexibility and an acceptable grade of service. The problem is modeled taking a network graph, where the nodes represents either the Access Points of IEEE 802.11 or wired backbone gateways. In this paper, we present two methods (1 an innovative approach using integer linear programming (ILP for gateway selection in the cellular Wi-Fi network, and (2 a completely new heuristic (OPEN/CLOSE to solve the gateway selection problem. In the ILP model, we developed a set of linear inequalities based on various constraints. The ILP model is solved by using lp-solve, a simplex-based software for linear and integer programming problems. The second approach is an OPEN/CLOSE heuristic, tailored for cellular Wi-Fi, which arrives at a sub-optimal solution. Java programming language is used for simulation in OPEN/CLOSE heuristic. Extensive simulations are carried out for performance evaluation. Simulation results show that the proposed approaches can effectively identify a set of gateways at optimal locations in a cellular Wi-Fi network, resulting in an overall cost reduction of up to 50%. The technique presented in this paper is generalized and can be used for gateway selection for other networks as well.

  16. Millimeter-Wave Evolution for 5G Cellular Networks

    Science.gov (United States)

    Sakaguchi, Kei; Tran, Gia Khanh; Shimodaira, Hidekazu; Nanba, Shinobu; Sakurai, Toshiaki; Takinami, Koji; Siaud, Isabelle; Strinati, Emilio Calvanese; Capone, Antonio; Karls, Ingolf; Arefi, Reza; Haustein, Thomas

    Triggered by the explosion of mobile traffic, 5G (5th Generation) cellular network requires evolution to increase the system rate 1000 times higher than the current systems in 10 years. Motivated by this common problem, there are several studies to integrate mm-wave access into current cellular networks as multi-band heterogeneous networks to exploit the ultra-wideband aspect of the mm-wave band. The authors of this paper have proposed comprehensive architecture of cellular networks with mm-wave access, where mm-wave small cell basestations and a conventional macro basestation are connected to Centralized-RAN (C-RAN) to effectively operate the system by enabling power efficient seamless handover as well as centralized resource control including dynamic cell structuring to match the limited coverage of mm-wave access with high traffic user locations via user-plane/control-plane splitting. In this paper, to prove the effectiveness of the proposed 5G cellular networks with mm-wave access, system level simulation is conducted by introducing an expected future traffic model, a measurement based mm-wave propagation model, and a centralized cell association algorithm by exploiting the C-RAN architecture. The numerical results show the effectiveness of the proposed network to realize 1000 times higher system rate than the current network in 10 years which is not achieved by the small cells using commonly considered 3.5 GHz band. Furthermore, the paper also gives latest status of mm-wave devices and regulations to show the feasibility of using mm-wave in the 5G systems.

  17. Area Green Efficiency (AGE) of Two Tier Heterogeneous Cellular Networks

    KAUST Repository

    Tabassum, Hina

    2012-10-03

    Small cell networks are becoming standard part of the future heterogeneous networks. In this paper, we consider a two tier heterogeneous network which promises energy savings by integrating the femto and macro cellular networks and thereby reducing CO2 emissions, operational and capital expenditures (OPEX and CAPEX) whilst enhancing the area spectral efficiency (ASE) of the network. In this context, we define a performance metric which characterize the aggregate energy savings per unit macrocell area and is referred to as area green efficiency (AGE) of the two tier heterogeneous network where the femto base stations are arranged around the edge of the reference macrocell such that the configuration is referred to as femto-on-edge (FOE). The mobile users in macro and femto cellular networks are transmitting with the adaptive power while maintaining the desired link quality such that the energy aware FOE configuration mandates to (i) save energy, and (ii) reduce the co-channel interference. We present a mathematical analysis to incorporate the uplink power control mechanism adopted by the mobile users and calibrate the uplink ASE and AGE of the energy aware FOE configuration. Next, we derive analytical expressions to compute the bounds on the uplink ASE of energy aware FOE configuration and demonstrate that the derived bounds are useful in evaluating the ASE under worst and best case interference scenarios. Simulation results are produced to demonstrate the ASE and AGE improvements in comparison to macro-only and macro-femto configuration with uniformly distributed femtocells.

  18. Resource Partitioning and Routing Optimization in Relay Enhanced Cellular Network

    Institute of Scientific and Technical Information of China (English)

    LIU Tao; RONG Meng-tian; SHI Hong-kui; XUE Yi-sheng

    2007-01-01

    A joint routing and resource partitioning scheme were proposed to improve cell capacity and user throughput of cellular network enhanced with two-hop fixed relay nodes (FRNs).Radio resources are partitioned under a reuse partitioning based framework, which guarantees effective and efficient inter-cell interference management.At the same time, each mobile terminal was assigned a channel-dependent route by the routing controller,which tries to maximize the cell capacity under the constraint imposed by reuse partitioning.Intensive computer simulations demonstrate the performance superiority of the FRN enhanced cellular network employing this scheme in comparison with conventional network, as well as the validity of the channel-dependent routing mechanism.

  19. Uplink Macro Diversity of Limited Backhaul Cellular Network

    CERN Document Server

    Sanderovich, Amichai; Poor, H Vincent; Shamai, Shlomo

    2008-01-01

    In this work new achievable rates are derived, for the uplink channel of a cellular network with joint multicell processing, where unlike previous results, the ideal backhaul network has finite capacity per-cell. Namely, the cell sites are linked to the central joint processor via lossless links with finite capacity. The cellular network is abstracted by symmetric models, which render analytical treatment plausible. For this idealistic model family, achievable rates are presented for cell-sites that use compress-and-forward schemes combined with local decoding, for both Gaussian and fading channels. The rates are given in closed form for the classical Wyner model and the soft-handover model. These rates are then demonstrated to be rather close to the optimal unlimited backhaul joint processing rates, already for modest backhaul capacities, supporting the potential gain offered by the joint multicell processing approach. Particular attention is also given to the low-SNR characterization of these rates through ...

  20. Selfish cellular networks and the evolution of complex organisms.

    Science.gov (United States)

    Kourilsky, Philippe

    2012-03-01

    Human gametogenesis takes years and involves many cellular divisions, particularly in males. Consequently, gametogenesis provides the opportunity to acquire multiple de novo mutations. A significant portion of these is likely to impact the cellular networks linking genes, proteins, RNA and metabolites, which constitute the functional units of cells. A wealth of literature shows that these individual cellular networks are complex, robust and evolvable. To some extent, they are able to monitor their own performance, and display sufficient autonomy to be termed "selfish". Their robustness is linked to quality control mechanisms which are embedded in and act upon the individual networks, thereby providing a basis for selection during gametogenesis. These selective processes are equally likely to affect cellular functions that are not gamete-specific, and the evolution of the most complex organisms, including man, is therefore likely to occur via two pathways: essential housekeeping functions would be regulated and evolve during gametogenesis within the parents before being transmitted to their progeny, while classical selection would operate on other traits of the organisms that shape their fitness with respect to the environment.

  1. Unified Stochastic Geometry Model for MIMO Cellular Networks with Retransmissions

    KAUST Repository

    Afify, Laila H.

    2016-10-11

    This paper presents a unified mathematical paradigm, based on stochastic geometry, for downlink cellular networks with multiple-input-multiple-output (MIMO) base stations (BSs). The developed paradigm accounts for signal retransmission upon decoding errors, in which the temporal correlation among the signal-to-interference-plus-noise-ratio (SINR) of the original and retransmitted signals is captured. In addition to modeling the effect of retransmission on the network performance, the developed mathematical model presents twofold analysis unification for MIMO cellular networks literature. First, it integrates the tangible decoding error probability and the abstracted (i.e., modulation scheme and receiver type agnostic) outage probability analysis, which are largely disjoint in the literature. Second, it unifies the analysis for different MIMO configurations. The unified MIMO analysis is achieved by abstracting unnecessary information conveyed within the interfering signals by Gaussian signaling approximation along with an equivalent SISO representation for the per-data stream SINR in MIMO cellular networks. We show that the proposed unification simplifies the analysis without sacrificing the model accuracy. To this end, we discuss the diversity-multiplexing tradeoff imposed by different MIMO schemes and shed light on the diversity loss due to the temporal correlation among the SINRs of the original and retransmitted signals. Finally, several design insights are highlighted.

  2. Some Useful Distributions and Probabilities for Cellular Networks

    CERN Document Server

    Yu, Seung Min

    2011-01-01

    The cellular network is one of the most useful networks for wireless communications and now universally used. There have been a lot of analytic results about the performance of the mobile user at a specific location such as the cell center or edge. On the other hand, there have been few analytic results about the performance of the mobile user at an arbitrary location. Moreover, to the best of our knowledge, there is no analytic result on the performance of the mobile user at an arbitrary location considering the mobile user density. In this paper, we use the stochastic geometry approach and derive useful distributions and probabilities for cellular networks. Using those, we analyze the performance of the mobile user, e.g., outage probability at an arbitrary location considering the mobile user density. Under some assumptions, those can be expressed by closed form formulas. Our analytic results will provide a fundamental framework for the performance analysis of cellular networks, which will significantly red...

  3. The role of actin networks in cellular mechanosensing

    Science.gov (United States)

    Azatov, Mikheil

    Physical processes play an important role in many biological phenomena, such as wound healing, organ development, and tumor metastasis. During these processes, cells constantly interact with and adapt to their environment by exerting forces to mechanically probe the features of their surroundings and generating appropriate biochemical responses. The mechanisms underlying how cells sense the physical properties of their environment are not well understood. In this thesis, I present my studies to investigate cellular responses to the stiffness and topography of the environment. In order to sense the physical properties of their environment, cells dynamically reorganize the structure of their actin cytoskeleton, a dynamic network of biopolymers, altering the shape and spatial distribution of protein assemblies. Several observations suggest that proteins that crosslink actin filaments may play an important role in cellular mechanosensitivity. Palladin is an actin-crosslinking protein that is found in the lamellar actin network, stress fibers and focal adhesions, cellular structures that are critical for mechanosensing of the physical environment. By virtue of its close interactions with these structures in the cell, palladin may play an important role in cell mechanics. However, the role of actin crosslinkers in general, and palladin in particular, in cellular force generation and mechanosensing is not well known. I have investigated the role of palladin in regulating the plasticity of the actin cytoskeleton and cellular force generation in response to alterations in substrate stiffness. I have shown that the expression levels of palladin modulate the forces exerted by cells and their ability to sense substrate stiffness. Perturbation experiments also suggest that palladin levels in cells altered myosin motor activity. These results suggest that the actin crosslinkers, such as palladin, and myosin motors coordinate for optimal cell function and to prevent aberrant

  4. Molecular chaperones: The modular evolution of cellular networks

    Indian Academy of Sciences (India)

    Tamás Korcsmáros; István A Kovács; Máté S Szalay; Péter Csermely

    2007-04-01

    Molecular chaperones play a prominent role in signaling and transcriptional regulatory networks of the cell. Recent advances uncovered that chaperones act as genetic buffers stabilizing the phenotype of various cells and organisms and may serve as potential regulators of evolvability. Chaperones have weak links, connect hubs, are in the overlaps of network modules and may uncouple these modules during stress, which gives an additional protection for the cell at the network-level. Moreover, after stress chaperones are essential to re-build inter-modular contacts by their low affinity sampling of the potential interaction partners in different modules. This opens the way to the chaperone-regulated modular evolution of cellular networks, and helps us to design novel therapeutic and anti-aging strategies.

  5. Fundamental Tradeoffs among Reliability, Latency and Throughput in Cellular Networks

    DEFF Research Database (Denmark)

    Soret, Beatriz; Mogensen, Preben; Pedersen, Klaus I.

    2014-01-01

    We address the fundamental tradeoffs among latency, reliability and throughput in a cellular network. The most important elements influencing the KPIs in a 4G network are identified, and the inter-relationships among them is discussed. We use the effective bandwidth and the effective capacity...... theory as analytical framework for calculating the maximum achievable rate for a given latency and reliability constraint. The analysis is conducted in a simplified LTE network, providing baseline - yet powerful - insight of the main tradeoffs. Guidelines to extend the theory to more complex systems...... are also presented, including a semi-analytical approach for cases with intractable channel and traffic models. We also discuss the use of system-level simulations to explore the limits of LTE networks. Based on our findings, we give some recommendations for the imminent 5G technology design phase...

  6. Integration of Neural Networks and Cellular Automata for Urban Planning

    Institute of Scientific and Technical Information of China (English)

    Anthony Gar-on Yeh; LI Xia

    2004-01-01

    This paper presents a new type of cellular automata (CA) model for the simulation of alternative land development using neural networks for urban planning. CA models can be regarded as a planning tool because they can generate alternative urban growth. Alternative development patterns can be formed by using different sets of parameter values in CA simulation. A critical issue is how to define parameter values for realistic and idealized simulation. This paper demonstrates that neural networks can simplify CA models but generate more plausible results. The simulation is based on a simple three-layer network with an output neuron to generate conversion probability. No transition rules are required for the simulation. Parameter values are automatically obtained from the training of network by using satellite remote sensing data. Original training data can be assessed and modified according to planning objectives. Alternative urban patterns can be easily formulated by using the modified training data sets rather than changing the model.

  7. Reconstruction of cellular forces in fibrous biopolymer network

    CERN Document Server

    Zhang, Yunsong; Heizler, Shay; Levine, Herbert

    2016-01-01

    How cells move through 3d extracellular matrix (ECM) is of increasing interest in attempts to understand important biological processes such as cancer metastasis. Just as in motion on 2d surfaces, it is expected that experimental measurements of cell-generated forces will provide valuable information for uncovering the mechanisms of cell migration. Here, we use a lattice-based mechanical model of ECM to study the cellular force reconstruction issue. We conceptually propose an efficient computational scheme to reconstruct cellular forces from the deformation and explore the performance of our scheme in presence of noise, varying marker bead distribution, varying bond stiffnesses and changing cell morphology. Our results show that micromechanical information, rather than merely the bulk rheology of the biopolymer networks, is essential for a precise recovery of cellular forces.

  8. Tensegrity II. How structural networks influence cellular information processing networks

    Science.gov (United States)

    Ingber, Donald E.

    2003-01-01

    The major challenge in biology today is biocomplexity: the need to explain how cell and tissue behaviors emerge from collective interactions within complex molecular networks. Part I of this two-part article, described a mechanical model of cell structure based on tensegrity architecture that explains how the mechanical behavior of the cell emerges from physical interactions among the different molecular filament systems that form the cytoskeleton. Recent work shows that the cytoskeleton also orients much of the cell's metabolic and signal transduction machinery and that mechanical distortion of cells and the cytoskeleton through cell surface integrin receptors can profoundly affect cell behavior. In particular, gradual variations in this single physical control parameter (cell shape distortion) can switch cells between distinct gene programs (e.g. growth, differentiation and apoptosis), and this process can be viewed as a biological phase transition. Part II of this article covers how combined use of tensegrity and solid-state mechanochemistry by cells may mediate mechanotransduction and facilitate integration of chemical and physical signals that are responsible for control of cell behavior. In addition, it examines how cell structural networks affect gene and protein signaling networks to produce characteristic phenotypes and cell fate transitions during tissue development.

  9. Modeling cellular networks in fading environments with dominant specular components

    KAUST Repository

    AlAmmouri, Ahmad

    2016-07-26

    Stochastic geometry (SG) has been widely accepted as a fundamental tool for modeling and analyzing cellular networks. However, the fading models used with SG analysis are mainly confined to the simplistic Rayleigh fading, which is extended to the Nakagami-m fading in some special cases. However, neither the Rayleigh nor the Nakagami-m accounts for dominant specular components (DSCs) which may appear in realistic fading channels. In this paper, we present a tractable model for cellular networks with generalized two-ray (GTR) fading channel. The GTR fading explicitly accounts for two DSCs in addition to the diffuse components and offers high flexibility to capture diverse fading channels that appear in realistic outdoor/indoor wireless communication scenarios. It also encompasses the famous Rayleigh and Rician fading as special cases. To this end, the prominent effect of DSCs is highlighted in terms of average spectral efficiency. © 2016 IEEE.

  10. Using Cellular Communication Networks To Detect Air Pollution.

    Science.gov (United States)

    David, Noam; Gao, H Oliver

    2016-09-06

    Accurate real time monitoring of atmospheric conditions at ground level is vital for hazard warning, meteorological forecasting, and various environmental applications required for public health and safety. However, conventional monitoring facilities are costly and often insufficient, for example, since they are not representative of the larger space and are not deployed densely enough in the field. There have been numerous scientific works showing the ability of commercial microwave links that comprise the data transmission infrastructure in cellular communication networks to monitor hydrometeors as a potential complementary solution. However, despite the large volume of research carried out in this emerging field during the past decade, no study has shown the ability of the system to provide critical information regarding air quality. Here we reveal the potential for identifying atmospheric conditions prone to air pollution by detecting temperature inversions that trap pollutants at ground level. The technique is based on utilizing standard signal measurements from an existing cellular network during routine operation.

  11. Analytical Evaluation of Fractional Frequency Reuse for OFDMA Cellular Networks

    CERN Document Server

    Novlan, Thomas David; Ghosh, Arunabha; Andrews, Jeffrey G

    2011-01-01

    Fractional frequency reuse (FFR) is an interference management technique well-suited to OFDMA-based cellular networks wherein the cells are partitioned into spatial regions with different frequency reuse factors. To date, FFR techniques have been typically been evaluated through system-level simulations using a hexagonal grid for the base station locations. This paper instead focuses on analytically evaluating the two main types of FFR deployments - Strict FFR and Soft Frequency Reuse (SFR) - using a Poisson point process to model the base station locations. The results are compared with the standard grid model and an actual urban deployment. Under reasonable special cases for modern cellular networks, our results reduce to simple closed-form expressions, which provide insight into system design guidelines and the relative merits of Strict FFR, SFR, universal reuse, and fixed frequency reuse. We observe that FFR provides an increase in the sum-rate as well as the well-known benefit of improved coverage for ce...

  12. Distributed Velocity-Dependent Protocol for Multihop Cellular Sensor Networks

    Directory of Open Access Journals (Sweden)

    Jagyasi Bhushan

    2009-01-01

    Full Text Available Abstract Cell phones are embedded with sensors form a Cellular Sensor Network which can be used to localize a moving event. The inherent mobility of the application and of the cell phone users warrants distributed structure-free data aggregation and on-the-fly routing. We propose a Distributed Velocity-Dependent (DVD protocol to localize a moving event using a Multihop Cellular Sensor Network (MCSN. DVD is based on a novel form of connectivity determined by the waiting time of nodes for a Random Waypoint (RWP distribution of cell phone users. This paper analyzes the time-stationary and spatial distribution of the proposed waiting time to explain the superior event localization and delay performances of DVD over the existing Randomized Waiting (RW protocol. A sensitivity analysis is also performed to compare the performance of DVD with RW and the existing Centralized approach.

  13. Distributed Velocity-Dependent Protocol for Multihop Cellular Sensor Networks

    Directory of Open Access Journals (Sweden)

    Deepthi Chander

    2009-01-01

    Full Text Available Cell phones are embedded with sensors form a Cellular Sensor Network which can be used to localize a moving event. The inherent mobility of the application and of the cell phone users warrants distributed structure-free data aggregation and on-the-fly routing. We propose a Distributed Velocity-Dependent (DVD protocol to localize a moving event using a Multihop Cellular Sensor Network (MCSN. DVD is based on a novel form of connectivity determined by the waiting time of nodes for a Random Waypoint (RWP distribution of cell phone users. This paper analyzes the time-stationary and spatial distribution of the proposed waiting time to explain the superior event localization and delay performances of DVD over the existing Randomized Waiting (RW protocol. A sensitivity analysis is also performed to compare the performance of DVD with RW and the existing Centralized approach.

  14. A Fluid Model for Performance Analysis in Cellular Networks

    Directory of Open Access Journals (Sweden)

    Coupechoux Marceau

    2010-01-01

    Full Text Available We propose a new framework to study the performance of cellular networks using a fluid model and we derive from this model analytical formulas for interference, outage probability, and spatial outage probability. The key idea of the fluid model is to consider the discrete base station (BS entities as a continuum of transmitters that are spatially distributed in the network. This model allows us to obtain simple analytical expressions to reveal main characteristics of the network. In this paper, we focus on the downlink other-cell interference factor (OCIF, which is defined for a given user as the ratio of its outer cell received power to its inner cell received power. A closed-form formula of the OCIF is provided in this paper. From this formula, we are able to obtain the global outage probability as well as the spatial outage probability, which depends on the location of a mobile station (MS initiating a new call. Our analytical results are compared to Monte Carlo simulations performed in a traditional hexagonal network. Furthermore, we demonstrate an application of the outage probability related to cell breathing and densification of cellular networks.

  15. Cellular Automata with network incubation in information technology diffusion

    Science.gov (United States)

    Guseo, Renato; Guidolin, Mariangela

    2010-06-01

    Innovation diffusion of network goods determines direct network externalities that depress sales for long periods and delay full benefits. We model this effect through a multiplicative dynamic market potential driven by a latent individual threshold embedded in a special Cellular Automata representation. The corresponding mean field approximation of its aggregate version is a Riccati equation with a closed form solution. This allows the detection of a change-point time separating an incubation period from a subsequent take-off due to a collective threshold (critical mass). Weighted nonlinear least squares are the main inferential methodology. An application is analysed with reference to USA fax machine diffusion.

  16. Digital implementation of shunting-inhibitory cellular neural network

    Science.gov (United States)

    Hammadou, Tarik; Bouzerdoum, Abdesselam; Bermak, Amine

    2000-05-01

    Shunting inhibition is a model of early visual processing which can provide contrast and edge enhancement, and dynamic range compression. An architecture of digital Shunting Inhibitory Cellular Neural Network for real time image processing is presented. The proposed architecture is intended to be used in a complete vision system for edge detection and image enhancement. The present hardware architecture, is modeled and simulated in VHDL. Simulation results show the functional validity of the proposed architecture.

  17. Behavior of impulsive fuzzy cellular neural networks with distributed delays

    Directory of Open Access Journals (Sweden)

    Kelin Li

    2007-04-01

    Full Text Available In this paper, we investigate a generalized model of fuzzy cellular neural networks with distributed delays and impulses. By employing the theory of topological degree, M-matrix and Lypunov functional, we find sufficient conditions for the existence, uniqueness and global exponential stability of both the equilibrium point and the periodic solution. Two examples are given to illustrate the results obtained here.

  18. Mobility-Aware User Association in Uplink Cellular Networks

    KAUST Repository

    Arshad, Rabe

    2017-07-20

    This letter studies the mobility aware user-to-BS association policies, within a stochastic geometry framework, in two tier uplink cellular networks with fractional channel inversion power control. Particularly, we model the base stations’ locations using the widely accepted poisson point process and obtain the coverage probability and handover cost expressions for the coupled and decoupled uplink and downlink associations. To this end, we compute the average throughput for the mobile users and study the merits and demerits of each association strategy.

  19. MIMO Cellular Networks with Simultaneous Wireless Information and Power Transfer

    OpenAIRE

    2016-01-01

    International audience; In this paper, we introduce a mathematical approach for system-level analysis and optimization of densely deployed multiple-antenna cellular networks, where low-energy devices are capable of decoding information data and harvesting power simultaneously. The base stations are assumed to be deployed according to a Poisson point process and tools from stochastic geometry are exploited to quantify the trade-off in terms of information rate and harvested power. It is shown ...

  20. Opportunistic Third-Party Backhaul for Cellular Wireless Networks

    OpenAIRE

    Ford, Russell; Kim, Changkyu; Rangan, Sundeep

    2013-01-01

    With high capacity air interfaces and large numbers of small cells, backhaul -- the wired connectivity to base stations -- is increasingly becoming the cost driver in cellular wireless networks. One reason for the high cost of backhaul is that capacity is often purchased on leased lines with guaranteed rates provisioned to peak loads. In this paper, we present an alternate \\emph{opportunistic backhaul} model where third parties provide base stations and backhaul connections and lease out exce...

  1. Hybrid Spectral Efficient Cellular Network Deployment to Reduce RF Pollution

    Science.gov (United States)

    Katiyar, Sumit; K. Jain, R.; K. Agrawal, N.

    2012-09-01

    As the mobile telecommunication systems are growing tremendously all over the world, the numbers of handheld and base stations are also rapidly growing and it became very popular to see these base stations distributed everywhere in the neighborhood and on roof tops which has caused a considerable amount of panic to the public in Palestine concerning wither the radiated electromagnetic fields from these base stations may cause any health effect or hazard. Recently UP High Court in India ordered for removal of BTS towers from residential area, it has created panic among cellular communication network designers too. Green cellular networks could be a solution for the above problem. This paper deals with green cellular networks with the help of multi-layer overlaid hierarchical structure (macro / micro / pico / femto cells). Macrocell for area coverage, micro for pedestrian and a slow moving traffic while pico for indoor use and femto for individual high capacity users. This could be the answer of the problem of energy conservation and enhancement of spectral density also.

  2. Reverse Engineering Cellular Networks with Information Theoretic Methods

    Directory of Open Access Journals (Sweden)

    Julio R. Banga

    2013-05-01

    Full Text Available Building mathematical models of cellular networks lies at the core of systems biology. It involves, among other tasks, the reconstruction of the structure of interactions between molecular components, which is known as network inference or reverse engineering. Information theory can help in the goal of extracting as much information as possible from the available data. A large number of methods founded on these concepts have been proposed in the literature, not only in biology journals, but in a wide range of areas. Their critical comparison is difficult due to the different focuses and the adoption of different terminologies. Here we attempt to review some of the existing information theoretic methodologies for network inference, and clarify their differences. While some of these methods have achieved notable success, many challenges remain, among which we can mention dealing with incomplete measurements, noisy data, counterintuitive behaviour emerging from nonlinear relations or feedback loops, and computational burden of dealing with large data sets.

  3. Robust network topologies for generating switch-like cellular responses.

    Directory of Open Access Journals (Sweden)

    Najaf A Shah

    2011-06-01

    Full Text Available Signaling networks that convert graded stimuli into binary, all-or-none cellular responses are critical in processes ranging from cell-cycle control to lineage commitment. To exhaustively enumerate topologies that exhibit this switch-like behavior, we simulated all possible two- and three-component networks on random parameter sets, and assessed the resulting response profiles for both steepness (ultrasensitivity and extent of memory (bistability. Simulations were used to study purely enzymatic networks, purely transcriptional networks, and hybrid enzymatic/transcriptional networks, and the topologies in each class were rank ordered by parametric robustness (i.e., the percentage of applied parameter sets exhibiting ultrasensitivity or bistability. Results reveal that the distribution of network robustness is highly skewed, with the most robust topologies clustering into a small number of motifs. Hybrid networks are the most robust in generating ultrasensitivity (up to 28% and bistability (up to 18%; strikingly, a purely transcriptional framework is the most fragile in generating either ultrasensitive (up to 3% or bistable (up to 1% responses. The disparity in robustness among the network classes is due in part to zero-order ultrasensitivity, an enzyme-specific phenomenon, which repeatedly emerges as a particularly robust mechanism for generating nonlinearity and can act as a building block for switch-like responses. We also highlight experimentally studied examples of topologies enabling switching behavior, in both native and synthetic systems, that rank highly in our simulations. This unbiased approach for identifying topologies capable of a given response may be useful in discovering new natural motifs and in designing robust synthetic gene networks.

  4. Network modules help the identification of key transport routes, signaling pathways in cellular and other networks

    CERN Document Server

    Palotai, Robin

    2009-01-01

    Complex systems are successfully reduced to interacting elements via the network concept. Transport plays a key role in the survival of networks. For example the specialized signaling cascades of cellular networks filter noise and efficiently adapt the network structure to new stimuli. However, our general understanding of transport mechanisms and signaling pathways in complex systems is yet limited. Here we summarize the key network structures involved in transport, list the solutions available to overloaded systems for relaxing their load and outline a possible method for the computational determination of signaling pathways. We highlight that in addition to hubs, bridges and the network skeleton, the overlapping modular structure is also essential in network transport. Moreover, by locating network elements in the space of overlapping network modules and evaluating their distance in this "module space", it may be possible to approximate signaling pathways computationally, which, in turn could serve the ide...

  5. Location Estimation and Mobility Prediction Using Neuro-fuzzy Networks In Cellular Networks

    OpenAIRE

    Maryam Borna; Mohammad Soleimani

    2011-01-01

    In this paper an approach is proposed for location estimation, tracking and mobility prediction in cellular networks in dense urban areas using neural and neuro-fuzzy networks. In urban areas with high buildings, due to the effects of multipath fading and Non-Line-of-Sight conditions, the accuracy of positioning methods based on direction finding and ranging degrades significantly. Also in these areas, due to high user traffic there's a need for network resources management. Knowing the next ...

  6. Energy Efficient Resource Allocation for Phantom Cellular Networks

    KAUST Repository

    Abdelhady, Amr

    2016-04-01

    Multi-tier heterogeneous networks have become an essential constituent for next generation cellular networks. Meanwhile, energy efficiency (EE) has been considered a critical design criterion along with the traditional spectral efficiency (SE) metric. In this context, we study power and spectrum allocation for the recently proposed two-tier network architecture known as phantom cellular networks. The optimization framework includes both EE and SE. First, we consider sparsely deployed cells experiencing negligible interference and assume perfect channel state information (CSI). For this setting, we propose an algorithm that finds the SE and EE resource allocation strategies. Then, we compare the performance of both design strategies versus number of users, and phantom cells share of the total available resource units (RUs). We aim to investigate the effect of some system parameters to achieve improved SE performance at a non-significant loss in EE performance, or vice versa. It is found that increasing phantom cells share of RUs decreases the SE performance loss due to EE optimization when compared with the optimized SE performance. Second, we consider the densely deployed phantom cellular networks and model the EE optimization problem having into consideration the inevitable interference and imperfect channel estimation. To this end, we propose three resource allocation strategies aiming at optimizing the EE performance metric of this network. Furthermore, we investigate the effect of changing some of the system parameters on the performance of the proposed strategies, such as phantom cells share of RUs, number of deployed phantom cells within a macro cell coverage, number of pilots and the maximum power available for transmission by the phantom cells BSs. It is found that increasing the number of pilots deteriorates the EE performance of the whole setup, while increasing maximum power available for phantom cells transmissions reduces the EE of the whole setup in a

  7. Mechanics of composite actin networks: in vitro and cellular perspectives

    Science.gov (United States)

    Upadhyaya, Arpita

    2014-03-01

    Actin filaments and associated actin binding proteins play an essential role in governing the mechanical properties of eukaryotic cells. Even though cells have multiple actin binding proteins (ABPs) that exist simultaneously to maintain the structural and mechanical integrity of the cellular cytoskeleton, how these proteins work together to determine the properties of actin networks is not well understood. The ABP, palladin, is essential for the integrity of cell morphology and movement during development. Palladin coexists with alpha-actinin in stress fibers and focal adhesions and binds to both actin and alpha-actinin. To obtain insight into how mutually interacting actin crosslinking proteins modulate the properties of actin networks, we have characterized the micro-structure and mechanics of actin networks crosslinked with palladin and alpha-actinin. Our studies on composite networks of alpha-actinin/palladin/actin show that palladin and alpha-actinin synergistically determine network viscoelasticity. We have further examined the role of palladin in cellular force generation and mechanosensing. Traction force microscopy revealed that TAFs are sensitive to substrate stiffness as they generate larger forces on substrates of increased stiffness. Contrary to expectations, knocking down palladin increased the forces generated by cells, and also inhibited the ability to sense substrate stiffness for very stiff gels. This was accompanied by significant differences in the actin organization and adhesion dynamics of palladin knock down cells. Perturbation experiments also suggest altered myosin activity in palladin KD cells. Our results suggest that the actin crosslinkers such as palladin and myosin motors coordinate for optimal cell function and to prevent aberrant behavior as in cancer metastasis.

  8. Study and Simulation of Traffic Behavior in Cellular Network

    Science.gov (United States)

    Madhup, D. K.; Shrestha, C. L.; Sharma, R. K.

    2007-07-01

    Cellular radio systems accommodate a large number of users with a limited radio spectrum. The concept of trunking allows a large number of users to share the relatively small number of channels in a cell by providing access to each user, on demand, from a pool of available channels. Traffic engineering deals with provisioning of communication circuits in a given area for a number of subscribers with a required grade of service. Traffic in any cell depends upon the number of users, the average request rate and average call duration. Certain number of channels is required for the required GOS. To design an optimum capacity cellular system, traffic behavior on that system is important. The number of channel required can be estimated by using Erlang formula and Erlang table. Erlang table is not always useful to calculate the probability of blocking in various complex scenarios such as channel borrowing strategies. When the total number of channel available in a given cell are divided to serve partly for newly generated calls and partly for handover calls, and if they use dynamic channel assignment strategies like channel borrowing, then the probability of blocking can't be calculated from Erlang table. Simulation model of the behavior help us to determine the blocking and the channel utilization while using various channel assignment strategies. The title "Study and Simulation of Traffic Behavior in Cellular Network" entail the study of the blocking probability of traffic in cellular network for static channel assignment strategies and dynamic channel borrowing strategies through MATLAB programming language and graphic user interface (GUI). The result shows that the dynamic scheme can perform better than static maximizing the overall utilization of the circuits and minimizing the overall blocking.

  9. Controllability of time-varying cellular neural networks

    Directory of Open Access Journals (Sweden)

    Wadie Aziz

    2005-11-01

    Full Text Available In this work, we consider the model of Cellular Neural Network (CNN introduced by Chua and Yang in 1988, but with the cloning templates $omega$-periodic in time. By imposing periodic boundary conditions the matrices involved in the system become circulant and $omega$-periodic. We show some results on the controllability of the linear model using a Theorem by Brunovsky for the case of linear and $omega$-periodic system. Also we use this approach in image detection, specifically foreground, background and contours of figures in different scales of grey.

  10. Chaotic phenomena in Josephson circuits coupled quantum cellular neural networks

    Institute of Scientific and Technical Information of China (English)

    Wang Sen; Cai Li; Li Qin; Wu Gang

    2007-01-01

    In this paper the nonlinear dynamical behaviour of a quantum cellular neural network (QCNN) by coupling Josephson circuits was investigated and it was shown that the QCNN using only two of them can cause the onset of chaotic oscillation. The theoretical analysis and simulation for the two Josephson-circuits-coupled QCNN have been done by using the amplitude and phase as state variables. The complex chaotic behaviours can be observed and then proved by calculating Lyapunov exponents. The study provides valuable information about QCNNs for future application in high-parallel signal processing and novel chaotic generators.

  11. Sources of Uncertainty in Rainfall Maps from Cellular Communication Networks

    Science.gov (United States)

    Rios Gaona, Manuel Felipe; Overeem, Aart; Leijnse, Hidde; Uijlenhoet, Remko

    2015-04-01

    and quantify the sources of uncertainty in such rainfall maps, but also to test the actual and optimal performance of one commercial microwave network from one of the cellular providers in The Netherlands.

  12. GPM ground validation via commercial cellular networks: an exploratory approach

    Science.gov (United States)

    Rios Gaona, Manuel Felipe; Overeem, Aart; Leijnse, Hidde; Brasjen, Noud; Uijlenhoet, Remko

    2016-04-01

    The suitability of commercial microwave link networks for ground validation of GPM (Global Precipitation Measurement) data is evaluated here. Two state-of-the-art rainfall products are compared over the land surface of the Netherlands for a period of 7 months, i.e., rainfall maps from commercial cellular communication networks and Integrated Multi-satellite Retrievals for GPM (IMERG). Commercial microwave link networks are nowadays the core component in telecommunications worldwide. Rainfall rates can be retrieved from measurements of attenuation between transmitting and receiving antennas. If adequately set up, these networks enable rainfall monitoring tens of meters above the ground at high spatiotemporal resolutions (temporal sampling of seconds to tens of minutes, and spatial sampling of hundreds of meters to tens of kilometers). The GPM mission is the successor of TRMM (Tropical Rainfall Measurement Mission). For two years now, IMERG offers rainfall estimates across the globe (180°W - 180°E and 60°N - 60°S) at spatiotemporal resolutions of 0.1° x 0.1° every 30 min. These two data sets are compared against a Dutch gauge-adjusted radar data set, considered to be the ground truth given its accuracy, spatiotemporal resolution and availability. The suitability of microwave link networks in satellite rainfall evaluation is of special interest, given the independent character of this technique, its high spatiotemporal resolutions and availability. These are valuable assets for water management and modeling of floods, landslides, and weather extremes; especially in places where rain gauge networks are scarce or poorly maintained, or where weather radar networks are too expensive to acquire and/or maintain.

  13. Interference Mitigation Framework for Cellular Mobile Radio Networks

    Directory of Open Access Journals (Sweden)

    Wolfgang Mennerich

    2013-01-01

    Full Text Available For today's cellular mobile communication networks, the needed capacity is hard to realize without much more of (expensive bandwidth. Thus new standards like LTE were developed. LTE advanced is in discussion as the successor of LTE and cooperative multipoint transmission (CoMP is one of the hot topics to increase the system's capacity. System simulations often show only weak gains of the signal-to-interference ratio due to high interference from noncooperating cells in the downlink. This paper presents an interference mitigation framework to overcome the hardest issue, that is, the low penetration rate of mobile stations that can be served from a cluster composed of their strongest cells in the network. The results obtained from simulation tools are discussed with values resulting from testbed on the TU Dresden. They show that the theoretical ideas can be transferred into gains on real systems.

  14. Joint Uplink and Downlink Relay Selection in Cooperative Cellular Networks

    CERN Document Server

    Yang, Wei; Wu, Gang; Wang, Haifeng; Wang, Ying

    2010-01-01

    We consider relay selection technique in a cooperative cellular network where user terminals act as mobile relays to help the communications between base station (BS) and mobile station (MS). A novel relay selection scheme, called Joint Uplink and Downlink Relay Selection (JUDRS), is proposed in this paper. Specifically, we generalize JUDRS in two key aspects: (i) relay is selected jointly for uplink and downlink, so that the relay selection overhead can be reduced, and (ii) we consider to minimize the weighted total energy consumption of MS, relay and BS by taking into account channel quality and traffic load condition of uplink and downlink. Information theoretic analysis of the diversity-multiplexing tradeoff demonstrates that the proposed scheme achieves full spatial diversity in the quantity of cooperating terminals in this network. And numerical results are provided to further confirm a significant energy efficiency gain of the proposed algorithm comparing to the previous best worse channel selection an...

  15. A Self-organized MIMO-OFDM-based Cellular Network

    Science.gov (United States)

    Grünheid, Rainer; Fellenberg, Christian

    2012-05-01

    This paper presents a system proposal for a self-organized cellular network, which is based on the MIMO-OFDM transmission technique. Multicarrier transmission, combined with appropriate beamforming concepts, yields high bandwidth-efficiency and shows a robust behavior in multipath radio channels. Moreover, it provides a fine and tuneable granularity of space-time-frequency resources. Using a TDD approach and interference measurements in each cell, the Base Stations (BSs) decide autonomously which of the space-time-frequency resource blocks are allocated to the Mobile Terminals (MTs) in the cell, in order to fulfil certain Quality of Service (QoS) parameters. Since a synchronized Single Frequency Network (SFN), i.e., a re-use factor of one is applied, the resource blocks can be shared adaptively and flexibly among the cells, which is very advantageous in the case of a non-uniform MT distribution.

  16. AN EFFICIENT UE CLUSTER HEAD SELECTION ALGORITHM IN WIRELESS SENSOR NETWORKS AND CELLULAR NETWORKS

    Institute of Scientific and Technical Information of China (English)

    Shan Lianhai; Ouyang Yuling; Yuan Zhi; Fang Weidong; Hu Honglin

    2013-01-01

    Wireless Sensor Networks (WSNs) have been applied in many different areas.Energy etficient algorithms and protocols have become one of the most challenging issues for WSN.Many researchers focused on developing energy efficient clustering algorithms for WSN,but less research has been concerned in the mobile User Equipment (UE) acting as a Cluster Head (CH) for data transmission between cellular networks and WSNs.In this paper,we propose a cellular-assisted UE CH selection algorithm for the WSN,which considers several parameters to choose the optimal UE gateway CH.We analyze the energy cost of data transmission from a sensor node to the next node or gateway and calculate the whole system energy cost for a WSN.Simulation results show that better system performance,in terms of system energy cost and WSNs life time,can be achieved by using interactive optimization with cellular networks.

  17. Network modeling of membrane-based artificial cellular systems

    Science.gov (United States)

    Freeman, Eric C.; Philen, Michael K.; Leo, Donald J.

    2013-04-01

    Computational models are derived for predicting the behavior of artificial cellular networks for engineering applications. The systems simulated involve the use of a biomolecular unit cell, a multiphase material that incorporates a lipid bilayer between two hydrophilic compartments. These unit cells may be considered building blocks that enable the fabrication of complex electrochemical networks. These networks can incorporate a variety of stimuli-responsive biomolecules to enable a diverse range of multifunctional behavior. Through the collective properties of these biomolecules, the system demonstrates abilities that recreate natural cellular phenomena such as mechanotransduction, optoelectronic response, and response to chemical gradients. A crucial step to increase the utility of these biomolecular networks is to develop mathematical models of their stimuli-responsive behavior. While models have been constructed deriving from the classical Hodgkin-Huxley model focusing on describing the system as a combination of traditional electrical components (capacitors and resistors), these electrical elements do not sufficiently describe the phenomena seen in experiment as they are not linked to the molecular scale processes. From this realization an advanced model is proposed that links the traditional unit cell parameters such as conductance and capacitance to the molecular structure of the system. Rather than approaching the membrane as an isolated parallel plate capacitor, the model seeks to link the electrical properties to the underlying chemical characteristics. This model is then applied towards experimental cases in order that a more complete picture of the underlying phenomena responsible for the desired sensing mechanisms may be constructed. In this way the stimuli-responsive characteristics may be understood and optimized.

  18. Perturbation biology: inferring signaling networks in cellular systems.

    Science.gov (United States)

    Molinelli, Evan J; Korkut, Anil; Wang, Weiqing; Miller, Martin L; Gauthier, Nicholas P; Jing, Xiaohong; Kaushik, Poorvi; He, Qin; Mills, Gordon; Solit, David B; Pratilas, Christine A; Weigt, Martin; Braunstein, Alfredo; Pagnani, Andrea; Zecchina, Riccardo; Sander, Chris

    2013-01-01

    We present a powerful experimental-computational technology for inferring network models that predict the response of cells to perturbations, and that may be useful in the design of combinatorial therapy against cancer. The experiments are systematic series of perturbations of cancer cell lines by targeted drugs, singly or in combination. The response to perturbation is quantified in terms of relative changes in the measured levels of proteins, phospho-proteins and cellular phenotypes such as viability. Computational network models are derived de novo, i.e., without prior knowledge of signaling pathways, and are based on simple non-linear differential equations. The prohibitively large solution space of all possible network models is explored efficiently using a probabilistic algorithm, Belief Propagation (BP), which is three orders of magnitude faster than standard Monte Carlo methods. Explicit executable models are derived for a set of perturbation experiments in SKMEL-133 melanoma cell lines, which are resistant to the therapeutically important inhibitor of RAF kinase. The resulting network models reproduce and extend known pathway biology. They empower potential discoveries of new molecular interactions and predict efficacious novel drug perturbations, such as the inhibition of PLK1, which is verified experimentally. This technology is suitable for application to larger systems in diverse areas of molecular biology.

  19. Evolutionary principles underlying structure and response dynamics of cellular networks.

    Science.gov (United States)

    Steinacher, Arno; Soyer, Orkun S

    2012-01-01

    The network view in systems biology, in conjunction with the continuing development of experimental technologies, is providing us with the key structural and dynamical features of both cell-wide and pathway-level regulatory, signaling and metabolic systems. These include for example modularity and presence of hub proteins at the structural level and ultrasensitivity and feedback control at the level of dynamics. The uncovering of such features, and the seeming commonality of some of them, makes many systems biologists believe that these could represent design principles that underpin cellular systems across organisms. Here, we argue that such claims on any observed feature requires an understanding of how it has emerged in evolution and how it can shape subsequent evolution. We review recent and past studies that aim to achieve such evolutionary understanding for observed features of cellular networks. We argue that this evolutionary framework could lead to deciphering evolutionary origin and relevance of proposed design principles, thereby allowing to predict their presence or absence in an organism based on its environment and biochemistry and their effect on its future evolution.

  20. Beacon-Based Service Publishing Framework in Multiservice Wi-Fi Hotspots

    Directory of Open Access Journals (Sweden)

    Di Sorte Dario

    2007-01-01

    Full Text Available In an expected future multiaccess and multiservice IEEE 802.11 environment, the problem of providing users with useful service-related information to support a correct rapid network selection is expected to become a very important issue. A feasible short-term 802.11-tailored working solution, compliant with existing equipment, is to publish service information encoded within the SSID information element within beacon frames. This makes it possible for an operator to implement service publishing in 802.11 networks while waiting for a standardized mechanism. Also, this straightforward approach has allowed us to evaluate experimentally the performance of a beacon-based service publishing solution. In fact, the main focus of the paper is indeed to present a quantitative comparison of service discovery times between the legacy scenario, where the user is forced to associate and authenticate with a network point of access to check its service offer, and the enhanced scenario where the set of service-related information is broadcasted within beacons. These discovery times are obtained by processing the results of a measurement campaign performed in a multiaccess/service 802.11 environment. This analysis confirms the effectiveness of the beacon-based approach. We also show that the cost in terms of wireless bandwidth consumption of such solution is low.

  1. Assessing the weather monitoring capabilities of cellular microwave link networks

    Science.gov (United States)

    Fencl, Martin; Vrzba, Miroslav; Rieckermann, Jörg; Bareš, Vojtěch

    2016-04-01

    Using of microwave links for rainfall monitoring was suggested already by (Atlas and Ulbrich, 1977). However, this technique attracted broader attention of scientific community only in the recent decade, with the extensive growth of cellular microwave link (CML) networks, which form the backbone of today's cellular telecommunication infrastructure. Several studies have already shown that CMLs can be conveniently used as weather sensors and have potential to provide near-ground path-integrated observations of rainfall but also humidity or fog. However, although research is still focusing on algorithms to improve the weather sensing capabilities (Fencl et al., 2015), it is not clear how to convince cellular operators to provide the power levels of their network. One step in this direction is to show in which regions or municipalities the networks are sufficiently dense to provide/develop good services. In this contribution we suggest a standardized approach to evaluate CML networks in terms of rainfall observation and to identify suitable regions for CML rainfall monitoring. We estimate precision of single CML based on its sensitivity to rainfall, i.e. as a function of frequency, polarization and path length. Capability of a network to capture rainfall spatial patterns is estimated from the CML coverage and path lengths considering that single CML provides path-integrated rain rates. We also search for suitable predictors for regions where no network topologies are available. We test our approach on several European networks and discuss the results. Our results show that CMLs are very dense in urban areas (> 1 CML/km2), but less in rural areas (density (e.g. R2 = 0.97 in Czech Republic), thus population could be a simple proxy to identify suitable regions for CML weather monitoring. To enable a simple and efficient assessment of the CML monitoring potential for any region worldwide, we are currently integrating our approach into open source online tool. In summary

  2. Collaborative Multi-Layer Network Coding in Hybrid Cellular Cognitive Radio Networks

    KAUST Repository

    Moubayed, Abdallah J.

    2015-05-01

    In this paper, as an extension to [1], we propose a prioritized multi-layer network coding scheme for collaborative packet recovery in hybrid (interweave and underlay) cellular cognitive radio networks. This scheme allows the uncoordinated collaboration between the collocated primary and cognitive radio base-stations in order to minimize their own as well as each other\\'s packet recovery overheads, thus by improving their throughput. The proposed scheme ensures that each network\\'s performance is not degraded by its help to the other network. Moreover, it guarantees that the primary network\\'s interference threshold is not violated in the same and adjacent cells. Yet, the scheme allows the reduction of the recovery overhead in the collocated primary and cognitive radio networks. The reduction in the cognitive radio network is further amplified due to the perfect detection of spectrum holes which allows the cognitive radio base station to transmit at higher power without fear of violating the interference threshold of the primary network. For the secondary network, simulation results show reductions of 20% and 34% in the packet recovery overhead, compared to the non-collaborative scheme, for low and high probabilities of primary packet arrivals, respectively. For the primary network, this reduction was found to be 12%. © 2015 IEEE.

  3. Dynamic Topology Re-Configuration in Multihop Cellular Networks Using Sequential Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    B.Shantha Kumari

    2014-10-01

    Full Text Available Cellular communications has experienced explosive growth in the past two decades. Today millions of people around the world use cellular phones. Cellular phones allow a person to make or receive a call from almost anywhere. Likewise, a person is allowed to continue the phone conversation while on the move. Cellular communications is supported by an infrastructure called a cellular network, which integrates cellular phones into the public switched telephone network. The cellular network has gone through three generations.The first generation of cellular networks is analog in nature. To accommodate more cellular phone subscribers, digital TDMA (time division multiple access and CDMA (code division multiple access technologies are used in the second generation (2G to increase the network capacity. With digital technologies, digitized voice can be coded and encrypted. Therefore, the 2G cellular network is also more secure. The third generation (3G integrates cellular phones into the Internet world by providing highspeed packet-switching data transmission in addition to circuit-switching voice transmission. The 3G cellular networks have been deployed in some parts of Asia, Europe, and the United States since 2002 and will be widely deployed in the coming years. The high increase in traffic and data rate for future generations of mobile communication systems, with simultaneous requirement for reduced power consumption, makes Multihop Cellular Networks (MCNs an attractive technology. To exploit the potentials of MCNs a new network paradigm is proposed in this paper. In addition, a novel sequential genetic algorithm (SGA is proposed as a heuristic approximation to reconfigure the optimum relaying topology as the network traffic changes. Network coding is used to combine the uplink and downlink transmissions, and incorporate it into the optimum bidirectional relaying with ICI awareness. Numerical results have shown that the algorithms suggested in this

  4. Countrywide rainfall maps from a commercial cellular telecommunication network

    Science.gov (United States)

    Overeem, A.; Leijnse, H.; Uijlenhoet, R.

    2012-12-01

    Accurate rainfall observations with high spatial and temporal resolutions are needed for hydrological applications, agriculture, meteorology, and climate monitoring. However, the majority of the land surface of the earth lacks accurate rainfall information. Many countries do not have continuously operating weather radars, and have no or few rain gauges. A new development is rainfall estimation from microwave links of commercial cellular telecommunication networks. Such networks cover large parts of the land surface of the earth and have a high density, especially in urban areas. The estimation of rainfall using commercial microwave links could therefore become a valuable source of information. The data produced by microwave links is essentially a by-product of the communication between mobile telephones. Rainfall attenuates the electromagnetic signals transmitted from one telephone tower to another. By measuring the received power at one end of a microwave link as a function of time, the path-integrated attenuation due to rainfall can be calculated. Previous studies have shown that average rainfall intensities over the length of a link can be derived from the path-integrated attenuation. A dataset from a commercial microwave link network over the Netherlands is analyzed, containing data from an unprecedented number of links (1500) covering the land surface of the Netherlands (35500 km2). This dataset consists of 24 days with substantial rainfall in June - September 2011. A rainfall retrieval algorithm is presented to derive rainfall intensities from the microwave link data, which have a temporal resolution of 15 min. Rainfall maps (1 km spatial resolution) are generated from these rainfall intensities using Kriging. This algorithm is suited for real-time application, and is calibrated on a subset (12 days) of the dataset. The other 12 days in the dataset are used to validate the algorithm. Both calibration and validation are done using gauge-adjusted radar data

  5. Load-Aware Modeling and Analysis of Heterogeneous Cellular Networks

    CERN Document Server

    Dhillon, Harpreet S; Andrews, Jeffrey G

    2012-01-01

    Random spatial models are attractive for modeling heterogeneous cellular networks (HCNs) due to their realism, tractability, and scalability. A major limitation of such models to date in the context of HCNs is the neglect of network traffic and load: all base stations (BSs) have typically been assumed to always be transmitting. Small cells in particular will have a lighter load than macrocells, and so their contribution to the network interference may be significantly overstated in a fully loaded model. This paper incorporates a flexible notion of BS load by introducing a new idea of conditionally thinning the interference field. For a $K$-tier HCN where BSs across tiers differ in terms of transmit power, supported data rate, deployment density, and now load, we derive the coverage probability for a typical mobile, which connects to the strongest BS signal. Conditioned on this connection, the interfering BSs of the $i^{th}$ tier are assumed to transmit independently with probability $p_i$, which models the lo...

  6. Myosin lever arm directs collective motion on cellular actin network.

    Science.gov (United States)

    Hariadi, Rizal F; Cale, Mario; Sivaramakrishnan, Sivaraj

    2014-03-18

    The molecular motor myosin teams up to drive muscle contraction, membrane traffic, and cell division in biological cells. Myosin function in cells emerges from the interaction of multiple motors tethered to a scaffold, with surrounding actin filaments organized into 3D networks. Despite the importance of myosin function, the influence of intermotor interactions on collective motion remains poorly understood. In this study, we used precisely engineered myosin assemblies to examine emergence in collective myosin movement. We report that tethering multiple myosin VI motors, but not myosin V motors, modifies their movement trajectories on keratocyte actin networks. Single myosin V and VI dimers display similar skewed trajectories, albeit in opposite directions, when traversing the keratocyte actin network. In contrast, tethering myosin VI motors, but not myosin V motors, progressively straightens the trajectories with increasing myosin number. Trajectory shape of multimotor scaffolds positively correlates with the stiffness of the myosin lever arm. Swapping the flexible myosin VI lever arm for the relatively rigid myosin V lever increases trajectory skewness, and vice versa. A simplified model of coupled motor movement demonstrates that the differences in flexural rigidity of the two myosin lever arms is sufficient to account for the differences in observed behavior of groups of myosin V and VI motors. In accordance with this model trajectory, shapes for scaffolds containing both myosin V and VI are dominated by the myosin with a stiffer lever arm. Our findings suggest that structural features unique to each myosin type may confer selective advantages in cellular functions.

  7. Energy-efficient power control for OFDMA cellular networks

    KAUST Repository

    Sboui, Lokman

    2016-12-24

    In this paper, we study the energy efficiency (EE) of orthogonal frequency-division multiple access (OFDMA) cellular networks. Our objective is to present a power allocation scheme that maximizes the EE of downlink communications. We propose a novel explicit expression of the optimal power allocation to each subcarrier. We also present the power control when the transmit power is limited by power budget constraint or/and minimal rate constraint and we highlight the occurrence of some transmission outage events depending on the constraints\\' parameters. In the numerical results, we show that our proposed power control improves the EE especially at high power budget regime and low minimal rate regime. In addition, we show that having a higher number of subcarriers enhances the OFDMA EE.

  8. Cellular Neural Networks for NP-Hard Optimization

    Directory of Open Access Journals (Sweden)

    Mária Ercsey-Ravasz

    2009-02-01

    Full Text Available A cellular neural/nonlinear network (CNN is used for NP-hard optimization. We prove that a CNN in which the parameters of all cells can be separately controlled is the analog correspondent of a two-dimensional Ising-type (Edwards-Anderson spin-glass system. Using the properties of CNN, we show that one single operation (template always yields a local minimum of the spin-glass energy function. This way, a very fast optimization method, similar to simulated annealing, can be built. Estimating the simulation time needed on CNN-based computers, and comparing it with the time needed on normal digital computers using the simulated annealing algorithm, the results are astonishing. CNN computers could be faster than digital computers already at 10×10 lattice sizes. The local control of the template parameters was already partially realized on some of the hardwares, we think this study could further motivate their development in this direction.

  9. Analytical Evaluation of Fractional Frequency Reuse for Heterogeneous Cellular Networks

    CERN Document Server

    Novlan, Thomas D; Ghosh, Arunabha; Andrews, Jeffrey G

    2011-01-01

    Interference management techniques are critical to the performance of heterogeneous cellular networks, which will have dense and overlapping coverage areas, and experience high levels of interference. Fractional frequency reuse (FFR) is an attractive interference management technique due to its low complexity and overhead, and significant coverage improvement for low-percentile (cell-edge) users. Instead of relying on system simulations based on deterministic access point locations, this paper instead proposes an analytical model for evaluating Strict FFR and Soft Frequency Reuse (SFR) deployments based on the spatial Poisson point process. Our results both capture the non-uniformity of heterogeneous deployments and produce tractable expressions which can be used for system design with Strict FFR and SFR. We observe that the use of Strict FFR bands reserved for the users of each tier with the lowest average SINR provides the highest gains in terms of coverage and rate, while the use of SFR allows for more eff...

  10. Separation of Bouguer anomaly map using cellular neural network

    Science.gov (United States)

    Albora, A. Muhittin; Ucan, Osman N.; Ozmen, Atilla; Ozkan, Tulay

    2001-02-01

    In this paper, a modern image-processing technique, the Cellular Neural Network (CNN) has been firstly applied to Bouguer anomaly map of synthetic examples and then to data from the Sivas-Divrigi Akdag region. CNN is an analog parallel computing paradigm defined in space and characterized by the locality of connections between processing neurons. The behaviour of the CNN is defined by two template matrices and a template vector. We have optimised the weight coefficients of these templates using the Recurrent Perceptron Learning Algorithm (RPLA). After testing CNN performance on synthetic examples, the CNN approach has been applied to the Bouguer anomaly of Sivas-Divrigi Akdag region and the results match drilling logs done by Mineral Research and Exploration (MTA).

  11. Medical image segmentation based on cellular neural network

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The application of cellular neural network (CNN) has made great progress in image processing. When the selected objects extraction (SOE) CNN is applied to gray scale images, its effects depend on the choice of initial points. In this paper, we take medical images as an example to analyze this limitation. Then an improved algorithm is proposed in which we can segment any gray level objects regardless of the limitation stated above. We also use the gradient information and contour detection CNN to determine the contour and ensure the veracity of segmentation effectively. Finally, we apply the improved algorithm to tumor segmentation of the human brain MR image. The experimental results show that the algorithm is practical and effective.

  12. Service-Aware Retransmission Control in Cellular Networks

    Directory of Open Access Journals (Sweden)

    Nadhir Ben Halima

    2010-01-01

    Full Text Available This paper proposes a service-aware cross-layer approach between application/transport layers on the mobile terminal and link layer on the wireless base station to enable dynamic control on the level of per-packet error protection for multimedia data streams. Specifically, in the context of cellular networks, the proposed scheme enables the mobile terminal to specify to the base station the desired level of Hybrid ARQ (HARQ protection by using an in-band control feedback channel. Such protection is dynamically adapted on a per-packet basis and depends on the perceptual importance of different packets as well as on the reception history of the flow. Experimental results demonstrate the potential benefits deriving from the proposed strategy either for audio and video real-time streams as well as for TCP-based data transfers.

  13. Simulating Quantitative Cellular Responses Using Asynchronous Threshold Boolean Network Ensembles

    Directory of Open Access Journals (Sweden)

    Shah Imran

    2011-07-01

    Full Text Available Abstract Background With increasing knowledge about the potential mechanisms underlying cellular functions, it is becoming feasible to predict the response of biological systems to genetic and environmental perturbations. Due to the lack of homogeneity in living tissues it is difficult to estimate the physiological effect of chemicals, including potential toxicity. Here we investigate a biologically motivated model for estimating tissue level responses by aggregating the behavior of a cell population. We assume that the molecular state of individual cells is independently governed by discrete non-deterministic signaling mechanisms. This results in noisy but highly reproducible aggregate level responses that are consistent with experimental data. Results We developed an asynchronous threshold Boolean network simulation algorithm to model signal transduction in a single cell, and then used an ensemble of these models to estimate the aggregate response across a cell population. Using published data, we derived a putative crosstalk network involving growth factors and cytokines - i.e., Epidermal Growth Factor, Insulin, Insulin like Growth Factor Type 1, and Tumor Necrosis Factor α - to describe early signaling events in cell proliferation signal transduction. Reproducibility of the modeling technique across ensembles of Boolean networks representing cell populations is investigated. Furthermore, we compare our simulation results to experimental observations of hepatocytes reported in the literature. Conclusion A systematic analysis of the results following differential stimulation of this model by growth factors and cytokines suggests that: (a using Boolean network ensembles with asynchronous updating provides biologically plausible noisy individual cellular responses with reproducible mean behavior for large cell populations, and (b with sufficient data our model can estimate the response to different concentrations of extracellular ligands. Our

  14. Full-Duplex Communications in Large-Scale Cellular Networks

    KAUST Repository

    AlAmmouri, Ahmad

    2016-04-01

    In-band full-duplex (FD) communications have been optimistically promoted to improve the spectrum utilization and efficiency. However, the penetration of FD communications to the cellular networks domain is challenging due to the imposed uplink/downlink interference. This thesis presents a tractable framework, based on stochastic geometry, to study FD communications in multi-tier cellular networks. Particularly, we assess the FD communications effect on the network performance and quantify the associated gains. The study proves the vulnerability of the uplink to the downlink interference and shows that the improved FD rate gains harvested in the downlink (up to 97%) comes at the expense of a significant degradation in the uplink rate (up to 94%). Therefore, we propose a novel fine-grained duplexing scheme, denoted as α-duplex scheme, which allows a partial overlap between the uplink and the downlink frequency bands. We derive the required conditions to harvest rate gains from the α-duplex scheme and show its superiority to both the FD and half-duplex (HD) schemes. In particular, we show that the α-duplex scheme provides a simultaneous improvement of 28% for the downlink rate and 56% for the uplink rate. We also show that the amount of the overlap can be optimized based on the network design objective. Moreover, backward compatibility is an essential ingredient for the success of new technologies. In the context of in-band FD communication, FD base stations (BSs) should support HD users\\' equipment (UEs) without sacrificing the foreseen FD gains. The results show that FD-UEs are not necessarily required to harvest rate gains from FD-BSs. In particular, the results show that adding FD-UEs to FD-BSs offers a maximum of 5% rate gain over FD-BSs and HD-UEs case, which is a marginal gain compared to the burden required to implement FD transceivers at the UEs\\' side. To this end, we shed light on practical scenarios where HD-UEs operation with FD-BSs outperforms the

  15. Country-wide rainfall maps from cellular communication networks

    Science.gov (United States)

    Leijnse, Hidde; Overeem, Aart; Uijlenhoet, Remko

    2013-04-01

    Accurate rainfall observations with high spatial and temporal resolutions are needed for hydrological applications, agriculture, meteorology, and climate monitoring. However, the majority of the land surface of the earth lacks accurate rainfall information and the number of rain gauges is even severely declining in Europe, South-America, and Africa. This calls for alternative sources of rainfall information. Various studies have shown that microwave links from operational cellular telecommunication networks may be employed for rainfall monitoring. Such networks cover 20% of the land surface of the earth and have a high density, especially in urban areas. The basic principle of rainfall monitoring using microwave links is as follows. Rainfall attenuates the electromagnetic signals transmitted from one telephone tower to another. By measuring the received power at one end of a microwave link as a function of time, the path-integrated attenuation due to rainfall can be calculated. Previous studies have shown that average rainfall intensities over the length of a link can be derived from the path-integrated attenuation. Here we show how one cellular telecommunication network can be used to retrieve the space-time dynamics of rainfall for an entire country. A dataset from a commercial microwave link network over the Netherlands is analyzed, containing data from an unprecedented number of links (2400) covering the land surface of the Netherlands (35500 km2). This dataset consists of 24 days with substantial rainfall in June - September 2011. A rainfall retrieval algorithm is presented to derive rainfall intensities from the microwave link data, which have a temporal resolution of 15 min. Rainfall maps (1 km spatial resolution) are generated from these rainfall intensities using Kriging. This algorithm is suited for real-time application, and is calibrated on a subset (12 days) of the dataset. The other 12 days in the dataset are used to validate the algorithm. Both

  16. A Hybrid Energy Sharing Framework for Green Cellular Networks

    KAUST Repository

    Farooq, Muhammad Junaid

    2016-12-09

    Cellular operators are increasingly turning towards renewable energy (RE) as an alternative to using traditional electricity in order to reduce operational expenditure and carbon footprint. Due to the randomness in both RE generation and mobile traffic at each base station (BS), a surplus or shortfall of energy may occur at any given time. To increase energy selfreliance and minimize the network’s energy cost, the operator needs to efficiently exploit the RE generated across all BSs. In this paper, a hybrid energy sharing framework for cellular network is proposed, where a combination of physical power lines and energy trading with other BSs using smart grid is used. Algorithms for physical power lines deployment between BSs, based on average and complete statistics of the net RE available, are developed. Afterwards, an energy management framework is formulated to optimally determine the quantities of electricity and RE to be procured and exchanged among BSs, respectively, while considering battery capacities and real-time energy pricing. Three cases are investigated where RE generation is unknown, perfectly known, and partially known ahead of time. Results investigate the time varying energy management of BSs and demonstrate considerable reduction in average energy cost thanks to the hybrid energy sharing scheme.

  17. AdCell: Ad Allocation in Cellular Networks

    CERN Document Server

    Alaei, Saeed; Liaghat, Vahid; Pei, Dan; Saha, Barna

    2011-01-01

    With more than four billion usage of cellular phones worldwide, mobile advertising has become an attractive alternative to online advertisements. In this paper, we propose a new targeted advertising policy for Wireless Service Providers (WSPs) via SMS or MMS- namely {\\em AdCell}. In our model, a WSP charges the advertisers for showing their ads. Each advertiser has a valuation for specific types of customers in various times and locations and has a limit on the maximum available budget. Each query is in the form of time and location and is associated with one individual customer. In order to achieve a non-intrusive delivery, only a limited number of ads can be sent to each customer. Recently, new services have been introduced that offer location-based advertising over cellular network that fit in our model (e.g., ShopAlerts by AT&T) . We consider both online and offline version of the AdCell problem and develop approximation algorithms with constant competitive ratio. For the online version, we assume tha...

  18. Collaborative Multi-Layer Network Coding For Hybrid Cellular Cognitive Radio Networks

    KAUST Repository

    Moubayed, Abdallah J.

    2014-05-01

    In this thesis, as an extension to [1], we propose a prioritized multi-layer network coding scheme for collaborative packet recovery in hybrid (interweave and underlay) cellular cognitive radio networks. This scheme allows the uncoordinated collaboration between the collocated primary and cognitive radio base-stations in order to minimize their own as well as each other’s packet recovery overheads, thus by improving their throughput. The proposed scheme ensures that each network’s performance is not degraded by its help to the other network. Moreover, it guarantees that the primary network’s interference threshold is not violated in the same and adjacent cells. Yet, the scheme allows the reduction of the recovery overhead in the collocated primary and cognitive radio networks. The reduction in the cognitive radio network is further amplified due to the perfect detection of spectrum holes which allows the cognitive radio base station to transmit at higher power without fear of violating the interference threshold of the primary network. For the secondary network, simulation results show reductions of 20% and 34% in the packet recovery overhead, compared to the non-collaborative scheme, for low and high probabilities of primary packet arrivals, respectively. For the primary network, this reduction was found to be 12%. Furthermore, with the use of fractional cooperation, the average recovery overhead is further reduced by around 5% for the primary network and around 10% for the secondary network when a high fractional cooperation probability is used.

  19. Cellular computational networks--a scalable architecture for learning the dynamics of large networked systems.

    Science.gov (United States)

    Luitel, Bipul; Venayagamoorthy, Ganesh Kumar

    2014-02-01

    Neural networks for implementing large networked systems such as smart electric power grids consist of multiple inputs and outputs. Many outputs lead to a greater number of parameters to be adapted. Each additional variable increases the dimensionality of the problem and hence learning becomes a challenge. Cellular computational networks (CCNs) are a class of sparsely connected dynamic recurrent networks (DRNs). By proper selection of a set of input elements for each output variable in a given application, a DRN can be modified into a CCN which significantly reduces the complexity of the neural network and allows use of simple training methods for independent learning in each cell thus making it scalable. This article demonstrates this concept of developing a CCN using dimensionality reduction in a DRN for scalability and better performance. The concept has been analytically explained and empirically verified through application. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. User Association for Load Balancing in Heterogeneous Cellular Networks

    CERN Document Server

    Ye, Qiaoyang; Chen, Yudong; Al-Shalash, Mazin; Caramanis, Constantine; Andrews, Jeffrey G

    2012-01-01

    For small cell technology to significantly increase the capacity of tower-based cellular networks, mobile users will need to be actively pushed onto the more lightly loaded tiers (corresponding to, e.g., pico and femtocells), even if they offer a lower instantaneous SINR than the macrocell base station (BS). Optimizing a function of the long-term rates for each user requires (in general) a massive utility maximization problem over all the SINRs and BS loads. On the other hand, an actual implementation will likely resort to a simple biasing approach where a BS in tier j is treated as having its SINR multiplied by a factor A_j>=1, which makes it appear more attractive than the heavily-loaded macrocell. This paper bridges the gap between these approaches through several physical relaxations of the network-wide optimal association problem, whose solution is NP hard. We provide a low-complexity distributed algorithm that converges to a near-optimal solution with a theoretical performance guarantee, and we observe ...

  1. Collaborative multi-layer network coding for cellular cognitive radio networks

    KAUST Repository

    Sorour, Sameh

    2013-06-01

    In this paper, we propose a prioritized multi-layer network coding scheme for collaborative packet recovery in underlay cellular cognitive radio networks. This scheme allows the collocated primary and cognitive radio base-stations to collaborate with each other, in order to minimize their own and each other\\'s packet recovery overheads, and thus improve their throughput, without any coordination between them. This non-coordinated collaboration is done using a novel multi-layer instantly decodable network coding scheme, which guarantees that each network\\'s help to the other network does not result in any degradation in its own performance. It also does not cause any violation to the primary networks interference thresholds in the same and adjacent cells. Yet, our proposed scheme both guarantees the reduction of the recovery overhead in collocated primary and cognitive radio networks, and allows early recovery of their packets compared to non-collaborative schemes. Simulation results show that a recovery overhead reduction of 15% and 40% can be achieved by our proposed scheme in the primary and cognitive radio networks, respectively, compared to the corresponding non-collaborative scheme. © 2013 IEEE.

  2. Enhancement of Localization Accuracy in Cellular Networks via Cooperative AdHoc Links

    DEFF Research Database (Denmark)

    Lhomme, Edouard; Frattasi, Simone; Figueiras, Joao

    2006-01-01

    Positioning information enables new applications for cellular phones, personal communication systems, and specialized mobile radios. The network heterogeneity emerging in the fourth generation (4G) of mobile networks can be utilized for enhancements of the location estimation accuracy...

  3. Seeking Accountability: Multi-Service Accountability Agreements (MSAAs in Ontario’s Community Support Sector

    Directory of Open Access Journals (Sweden)

    Carolyn Steele Gray

    2014-02-01

    Full Text Available Multi-Service Accountability Agreements (MSAAs have been put in place to hold Community Sector Service (CSS agencies to account for services receiving public funding in Ontario. The MSAA seeks to support financial and performance accountability, requiring CSS agencies to report on their performance quarterly. The MSAA is an expenditure policy tool that has undergone several iterations, each informed by negotiations between the Ontario Ministry of Health and Long-Term Care (MOHLTC, the province’s regional authorities—known as Local Health Integration Networks (LHINs—and organizations/associations representing CSS agency interests. This approach to accountability is consistent with a broader focus on the government role as ‘steering’ service delivery rather than ‘rowing.’ The MSAA offers a standardized, politically acceptable approach to accountability. However, the MSAA relies heavily on performance indicators that may not adequately reflect quality care. The MSAA exemplifies the tension between the need for strong standardized accountability requirements for publicly-funded health service providers and the need for services that meet the needs of their communities.

  4. Using cellular network diagrams to interpret large-scale datasets: past progress and future challenges

    Science.gov (United States)

    Karp, Peter D.; Latendresse, Mario; Paley, Suzanne

    2011-03-01

    Cellular networks are graphs of molecular interactions within the cell. Thanks to the confluence of genome sequencing and bioinformatics, scientists are now able to reconstruct cellular network models for more than 1,000 organisms. A variety of bioinformatics tools have been developed to support the visualization and navigation of cellular network data. Another important application is the use of cellular network diagrams to visualize and interpret large-scale datasets, such as gene-expression data. We present the Cellular Overview, a network visualization tool developed at SRI International (SRI) to support visualization, navigation, and interpretation of large-scale datasets on metabolic networks. Different variations of the diagram have been generated algorithmically for more than 1,000 organisms. We discuss the graphical design of the diagram and its interactive capabilities.

  5. Environmental Monitoring using Measurements from Cellular Network Infrastructure

    Science.gov (United States)

    David, N.; Gao, O. H.

    2015-12-01

    atmospheric phenomena using current and future planned frequencies of cellular network infrastructure will be introduced.

  6. Hierarchical Interference Mitigation for Massive MIMO Cellular Networks

    Science.gov (United States)

    Liu, An; Lau, Vincent

    2014-09-01

    We propose a hierarchical interference mitigation scheme for massive MIMO cellular networks. The MIMO precoder at each base station (BS) is partitioned into an inner precoder and an outer precoder. The inner precoder controls the intra-cell interference and is adaptive to local channel state information (CSI) at each BS (CSIT). The outer precoder controls the inter-cell interference and is adaptive to channel statistics. Such hierarchical precoding structure reduces the number of pilot symbols required for CSI estimation in massive MIMO downlink and is robust to the backhaul latency. We study joint optimization of the outer precoders, the user selection, and the power allocation to maximize a general concave utility which has no closed-form expression. We first apply random matrix theory to obtain an approximated problem with closed-form objective. We show that the solution of the approximated problem is asymptotically optimal with respect to the original problem as the number of antennas per BS grows large. Then using the hidden convexity of the problem, we propose an iterative algorithm to find the optimal solution for the approximated problem. We also obtain a low complexity algorithm with provable convergence. Simulations show that the proposed design has significant gain over various state-of-the-art baselines.

  7. Modelling lava flows by Cellular Nonlinear Networks (CNN: preliminary results

    Directory of Open Access Journals (Sweden)

    C. Del Negro

    2005-01-01

    Full Text Available The forecasting of lava flow paths is a complex problem in which temperature, rheology and flux-rate all vary with space and time. The problem is more difficult to solve when lava runs down a real topography, considering that the relations between characteristic parameters of flow are typically nonlinear. An alternative approach to this problem that does not use standard differential equation methods is Cellular Nonlinear Networks (CNNs. The CNN paradigm is a natural and flexible framework for describing locally interconnected, simple, dynamic systems that have a lattice-like structure. They consist of arrays of essentially simple, nonlinearly coupled dynamic circuits containing linear and non-linear elements able to process large amounts of information in real time. Two different approaches have been implemented in simulating some lava flows. Firstly, a typical technique of the CNNs to analyze spatio-temporal phenomena (as Autowaves in 2-D and in 3-D has been utilized. Secondly, the CNNs have been used as solvers of partial differential equations of the Navier-Stokes treatment of Newtonian flow.

  8. Radio Resource Allocation on Complex 4G Wireless Cellular Networks

    Science.gov (United States)

    Psannis, Kostas E.

    2015-09-01

    In this article we consider the heuristic algorithm which improves step by step wireless data delivery over LTE cellular networks by using the total transmit power with the constraint on users’ data rates, and the total throughput with the constraints on the total transmit power as well as users’ data rates, which are jointly integrated into a hybrid-layer design framework to perform radio resource allocation for multiple users, and to effectively decide the optimal system parameter such as modulation and coding scheme (MCS) in order to adapt to the varying channel quality. We propose new heuristic algorithm which balances the accessible data rate, the initial data rates of each user allocated by LTE scheduler, the priority indicator which signals delay- throughput- packet loss awareness of the user, and the buffer fullness by achieving maximization of radio resource allocation for multiple users. It is noted that the overall performance is improved with the increase in the number of users, due to multiuser diversity. Experimental results illustrate and validate the accuracy of the proposed methodology.

  9. Network signatures of cellular immortalization in human lymphoblastoid cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Shim, Sung-Mi; Jung, So-Young; Nam, Hye-Young; Kim, Hye-Ryun; Lee, Mee-Hee; Kim, Jun-Woo; Han, Bok-Ghee [National Biobank of Korea, Center for Genome Science, Korea National Institute of Health, Osong 363-951 (Korea, Republic of); Jeon, Jae-Pil, E-mail: jaepiljeon@hanmail.net [Division of Brain Diseases, Center for Biomedical Science, Korea National Institute of Health, Osong 363-951 (Korea, Republic of)

    2013-11-15

    Highlights: •We identified network signatures of LCL immortalization from transcriptomic profiles. •More than 41% of DEGs are possibly regulated by miRNAs in LCLs. •MicroRNA target genes in LCLs are involved in apoptosis and immune-related functions. •This approach is useful to find functional miRNA targets in specific cell conditions. -- Abstract: Human lymphoblastoid cell line (LCL) has been used as an in vitro cell model in genetic and pharmacogenomic studies, as well as a good model for studying gene expression regulatory machinery using integrated genomic analyses. In this study, we aimed to identify biological networks of LCL immortalization from transcriptomic profiles of microRNAs and their target genes in LCLs. We first selected differentially expressed genes (DEGs) and microRNAs (DEmiRs) between early passage LCLs (eLCLs) and terminally differentiated late passage LCLs (tLCLs). The in silico and correlation analysis of these DEGs and DEmiRs revealed that 1098 DEG–DEmiR pairs were found to be positively (n = 591 pairs) or negatively (n = 507 pairs) correlated with each other. More than 41% of DEGs are possibly regulated by miRNAs in LCL immortalizations. The target DEGs of DEmiRs were enriched for cellular functions associated with apoptosis, immune response, cell death, JAK–STAT cascade and lymphocyte activation while non-miRNA target DEGs were over-represented for basic cell metabolisms. The target DEGs correlated negatively with miR-548a-3p and miR-219-5p were significantly associated with protein kinase cascade, and the lymphocyte proliferation and apoptosis, respectively. In addition, the miR-106a and miR-424 clusters located in the X chromosome were enriched in DEmiR–mRNA pairs for LCL immortalization. In this study, the integrated transcriptomic analysis of LCLs could identify functional networks of biologically active microRNAs and their target genes involved in LCL immortalization.

  10. Analysis And Augmentation Of Timing Advance Based Geolocation In Lte Cellular Networks

    Science.gov (United States)

    2016-12-01

    NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA DISSERTATION ANALYSIS AND AUGMENTATION OF TIMING ADVANCE-BASED GEOLOCATION IN LTE CELLULAR NETWORKS by...AND SUBTITLE ANALYSIS AND AUGMENTATION OF TIMING ADVANCE-BASED GEOLOCA- TION IN LTE CELLULAR NETWORKS 5. FUNDING NUMBERS 6. AUTHOR(S) John D. Roth 7...protection, and direct marketing. This work provides in-depth analysis of cellular positioning, which leverages the Long Term Evolution (LTE) signaling

  11. Cost-effective add-drop fiber optic microcell system for CDMA cellular network evolution

    Science.gov (United States)

    Cheong, Jong M.; Ham, David; Song, Myoung H.; Son, Yong S.

    2001-10-01

    In this paper, we propose a cost effective add-drop fiber-optic microcell system for CDMA cellular network. The add-drop microcell is compatible with the existing PCS or digital cellular services (DCS) systems & networks. The proposed fiber-optic add-drop access network is independent of the different channels and gives flexibility in evolution scenarios. This add-drop network provides the optimum solution to cut-down the additional rental fees by sharing the existing fiber-optic cable for cellular/PCS service providers who want to provide third generation services.

  12. Predict drug-protein interaction in cellular networking.

    Science.gov (United States)

    Xiao, Xuan; Min, Jian-Liang; Wang, Pu; Chou, Kuo-Chen

    2013-01-01

    Involved with many diseases such as cancer, diabetes, neurodegenerative, inflammatory and respiratory disorders, GPCRs (G-protein-coupled receptors) are the most frequent targets for drug development: over 50% of all prescription drugs currently on the market are actually acting by targeting GPCRs directly or indirectly. Found in every living thing and nearly all cells, ion channels play crucial roles for many vital functions in life, such as heartbeat, sensory transduction, and central nervous system response. Their dysfunction may have significant impact to human health, and hence ion channels are deemed as "the next GPCRs". To develop GPCR-targeting or ion-channel-targeting drugs, the first important step is to identify the interactions between potential drug compounds with the two kinds of protein receptors in the cellular networking. In this minireview, we are to introduce two predictors. One is called iGPCR-Drug accessible at http://www.jci-bioinfo.cn/iGPCR-Drug/; the other called iCDI-PseFpt at http://www.jci-bioinfo.cn/iCDI-PseFpt. The former is for identifying the interactions of drug compounds with GPCRs; while the latter for that with ion channels. In both predictors, the drug compound was formulated by the two-dimensional molecular fingerprint, and the protein receptor by the pseudo amino acid composition generated with the grey model theory, while the operation engine was the fuzzy K-nearest neighbor algorithm. For the convenience of most experimental pharmaceutical and medical scientists, a step-bystep guide is provided on how to use each of the two web-servers to get the desired results without the need to follow the complicated mathematics involved originally for their establishment.

  13. The Design of A Digital Family Multi-Service System Based on Triple-Play Technology

    Directory of Open Access Journals (Sweden)

    Yong Liu

    2013-04-01

    Full Text Available Under the background of three-net fusion, this study introduces a design of digital home multi-service system and elaborates from the perspective of digital TV broadcasting operation platform, interactive TV operation platform, home gateway and digital TV home multi-service terminals. This design is aimed to promote the two-way transformation of cable digital Television and the construction of operation platform. This will effectively help to accelerate the development of digital home service and broadcast television technology in Wujin.

  14. Analysis of blocking rate and bandwidth usage of mobile IPTV services in wireless cellular networks.

    Science.gov (United States)

    Li, Mingfu

    2014-01-01

    Mobile IPTV services over wireless cellular networks become more and more popular, owing to the significant growth in access bandwidth of wireless cellular networks such as 3G/4G and WiMAX. However, the spectrum resources of wireless cellular networks is rare. How to enhance the spectral efficiency of mobile networks becomes an important issue. Unicast, broadcast, and multicast are the most important transport schemes for offering mobile IPTV services over wireless cellular networks. Therefore, bandwidth usages and blocking rates of unicast, broadcast, and multicast IPTV services were analyzed and compared in this paper. Simulations were also conducted to validate the analytical results. Numerical results demonstrate that the presented analysis is correct, and multicast scheme achieves the best bandwidth usage and blocking rate performance, relative to the other two schemes.

  15. Loss Performance Modeling for Hierarchical Heterogeneous Wireless Networks With Speed-Sensitive Call Admission Control

    DEFF Research Database (Denmark)

    Huang, Qian; Huang, Yue-Cai; Ko, King-Tim;

    2011-01-01

    dimensioning and planning. This paper investigates the computationally efficient loss performance modeling for multiservice in hierarchical heterogeneous wireless networks. A speed-sensitive call admission control (CAC) scheme is considered in our model to assign overflowed calls to appropriate tiers...

  16. Cellular neural network analysis for two-dimensional bioheat transfer equation.

    Science.gov (United States)

    Niu, J H; Wang, H Z; Zhang, H X; Yan, J Y; Zhu, Y S

    2001-09-01

    The cellular neural network (CNN) method is applied to solve the Pennes bioheat transfer equation, and its feasibility is demonstrated. Numerical solutions were obtained for a cellular neural network for a two-dimensional steady-state temperature field obtained from focused and unfocused ultrasound heat sources. Transient-state temperature fields were also studied and compared with experimental results obtained elsewhere. The cellular neural networks' key features of asynchronous parallel processing, continuous-time dynamics and local interaction enable real-time temperature field estimation for clinical hyperthermia.

  17. Traffic Driven Analysis of Cellular and WiFi Networks

    Science.gov (United States)

    Paul, Utpal Kumar

    2012-01-01

    Since the days Internet traffic proliferated, measurement, monitoring and analysis of network traffic have been critical to not only the basic understanding of large networks, but also to seek improvements in resource management, traffic engineering and security. At the current times traffic in wireless local and wide area networks are facing…

  18. Traffic Driven Analysis of Cellular and WiFi Networks

    Science.gov (United States)

    Paul, Utpal Kumar

    2012-01-01

    Since the days Internet traffic proliferated, measurement, monitoring and analysis of network traffic have been critical to not only the basic understanding of large networks, but also to seek improvements in resource management, traffic engineering and security. At the current times traffic in wireless local and wide area networks are facing…

  19. Integrated cellular network of transcription regulations and protein-protein interactions

    Directory of Open Access Journals (Sweden)

    Chen Bor-Sen

    2010-03-01

    Full Text Available Abstract Background With the accumulation of increasing omics data, a key goal of systems biology is to construct networks at different cellular levels to investigate cellular machinery of the cell. However, there is currently no satisfactory method to construct an integrated cellular network that combines the gene regulatory network and the signaling regulatory pathway. Results In this study, we integrated different kinds of omics data and developed a systematic method to construct the integrated cellular network based on coupling dynamic models and statistical assessments. The proposed method was applied to S. cerevisiae stress responses, elucidating the stress response mechanism of the yeast. From the resulting integrated cellular network under hyperosmotic stress, the highly connected hubs which are functionally relevant to the stress response were identified. Beyond hyperosmotic stress, the integrated network under heat shock and oxidative stress were also constructed and the crosstalks of these networks were analyzed, specifying the significance of some transcription factors to serve as the decision-making devices at the center of the bow-tie structure and the crucial role for rapid adaptation scheme to respond to stress. In addition, the predictive power of the proposed method was also demonstrated. Conclusions We successfully construct the integrated cellular network which is validated by literature evidences. The integration of transcription regulations and protein-protein interactions gives more insight into the actual biological network and is more predictive than those without integration. The method is shown to be powerful and flexible and can be used under different conditions and for different species. The coupling dynamic models of the whole integrated cellular network are very useful for theoretical analyses and for further experiments in the fields of network biology and synthetic biology.

  20. Radio Access Sharing Strategies for Multiple Operators in Cellular Networks

    DEFF Research Database (Denmark)

    Popovska Avramova, Andrijana; Iversen, Villy Bæk

    2015-01-01

    deployments (required for coverage enhancement), increased base station utilization, and reduced overall power consumption. Today, network sharing in the radio access part is passive and limited to cell sites. With the introduction of Cloud Radio Access Network and Software Defined Networking adoption......Mobile operators are moving towards sharing network capacity in order to reduce capital and operational expenditures, while meeting the increasing demand for mobile broadband data services. Radio access network sharing is a promising technique that leads to reduced number of physical base station...... to the radio access network, the possibility for sharing baseband processing and radio spectrum becomes an important aspect of network sharing. This paper investigates strategies for active sharing of radio access among multiple operators, and analyses the individual benefits depending on the sharing degree...

  1. A Review on - Comparative Study of Issues in Cellular, Sensor and Adhoc Networks

    Directory of Open Access Journals (Sweden)

    Jayashree V. Shiral

    2012-05-01

    Full Text Available A cellular network is an asymmetric radio network which is made up of fixed transceivers or nodes, maintain the signal while the mobile transceiver which is using the network is in the vicinity of the node. An ad-hoc network is a local area network (LAN that is built spontaneously as devices connect. Instead of relying on a base station to coordinate the flow of messages to each node in the network, the individual network nodes forward packets to and from each other. This paper focuses on various issues in cellular, adhoc and sensor network. As issues proves helpful for forthcoming research, this paper work as a backbone to elaborate the various research areas.

  2. ON THE STABILITY OF THE CELLULAR NEURAL NETWORKS WITH TIME LAGS

    OpenAIRE

    Vladimir RASVAN; Daniela DANCIU

    2004-01-01

    Cellular neural networks (CNNs) are recurrent artificial neural networks. Due to their cyclic connections and to the neurons’ nonlinear activation functions, recurrent neural networks are nonlinear dynamic systems, which display stable and unstable fixed points, limit cycles and chaotic behavior. Since the field of neural networks is still a young one, improving the stability conditions for such systems is an obvious and quasipermanent task. This paper focuses on CNNs affected by time delays....

  3. An Analysis of Base Station Location Accuracy within Mobile-Cellular Networks

    Directory of Open Access Journals (Sweden)

    Liam Smit

    2015-05-01

    Full Text Available An important feature within a mobile-cellular net- work is that the location of a cellphone can be determined. As long as the cellphone is powered on, the location of the cellphone can always be traced to at least the cell from which it is receiving, or last received, signal from the cellular network. Such network-based methods of estimating the location of a cellphone is useful in cases where the cellphone user is unable or unwilling to reveal his or her location, and have practical value in digital forensic investigations. This study investigates the accuracy of using mobile-cellular network base station information for estimating the location of cellphones. Through quantitative analysis of mobile-cellular network base station data, large variations between the best and worst accuracy of recorded location information is exposed. Thus, depending on the requirements, base station locations may or may not be accurate enough for a particular application.

  4. Methods for the Analysis of Protein Phosphorylation-Mediated Cellular Signaling Networks

    Science.gov (United States)

    White, Forest M.; Wolf-Yadlin, Alejandro

    2016-06-01

    Protein phosphorylation-mediated cellular signaling networks regulate almost all aspects of cell biology, including the responses to cellular stimulation and environmental alterations. These networks are highly complex and comprise hundreds of proteins and potentially thousands of phosphorylation sites. Multiple analytical methods have been developed over the past several decades to identify proteins and protein phosphorylation sites regulating cellular signaling, and to quantify the dynamic response of these sites to different cellular stimulation. Here we provide an overview of these methods, including the fundamental principles governing each method, their relative strengths and weaknesses, and some examples of how each method has been applied to the analysis of complex signaling networks. When applied correctly, each of these techniques can provide insight into the topology, dynamics, and regulation of protein phosphorylation signaling networks.

  5. On the Global Dissipativity of a Class of Cellular Neural Networks with Multipantograph Delays

    Directory of Open Access Journals (Sweden)

    Liqun Zhou

    2011-01-01

    Full Text Available For the first time the global dissipativity of a class of cellular neural networks with multipantograph delays is studied. On the one hand, some delay-dependent sufficient conditions are obtained by directly constructing suitable Lyapunov functionals; on the other hand, firstly the transformation transforms the cellular neural networks with multipantograph delays into the cellular neural networks with constant delays and variable coefficients, and then constructing Lyapunov functionals, some delay-independent sufficient conditions are given. These new sufficient conditions can ensure global dissipativity together with their sets of attraction and can be applied to design global dissipative cellular neural networks with multipantograph delays and easily checked in practice by simple algebraic methods. An example is given to illustrate the correctness of the results.

  6. A Novel Approach for Attacks Mitigation in Mobile Ad Hoc Networks Using Cellular Automatas

    Directory of Open Access Journals (Sweden)

    Himadri Nath Saha

    2012-04-01

    Full Text Available Many security schemes for mobile ad-hoc network(MANET have been proposed so far but none of them has been successful in combating the different types of attacks that a mobile ad-hoc network often faces. This paper is providing one way of mitigating attacks in mobile ad-hoc networks by authenticating the node who tries to access this network .This scheme has been applied by using cellular automata (CA. Our simulation results show how cellular automata(CA is implemented for user authentication and secure transmission in MANET.

  7. Performance of multi-service system with retrials due to blocking and called-party-busy

    DEFF Research Database (Denmark)

    Stepanov, S.N.; Kokina, O.A.; Iversen, Villy Bæk

    2008-01-01

    In this paper we construct a model of a multi-service system with an arbitrary number of bandwidth flow demands, taking into account retrials due to both blocking along the route and to called-party-busy. An approximate algorithm for estimation of key performance measures is proposed...

  8. Efficient 3-D Placement of an Aerial Base Station in Next Generation Cellular Networks

    OpenAIRE

    Yaliniz, R. Irem Bor; El-Keyi, Amr; Yanikomeroglu, Halim

    2016-01-01

    Agility and resilience requirements of future cellular networks may not be fully satisfied by terrestrial base stations in cases of unexpected or temporary events. A promising solution is assisting the cellular network via low-altitude unmanned aerial vehicles equipped with base stations, i.e., drone-cells. Although drone-cells provide a quick deployment opportunity as aerial base stations, efficient placement becomes one of the key issues. In addition to mobility of the drone-cells in the ve...

  9. Joint Tilt Angle Adaptation and Beamforming in Multicell Multiuser Cellular Networks

    OpenAIRE

    Moghaddam, Soheil Khavari; Razavizadeh, S. Mohammad

    2017-01-01

    3D beamforming is a promising approach for interference coordination in cellular networks which brings significant improvements in comparison with conventional 2D beamforming techniques. This paper investigates the problem of joint beamforming design and tilt angle adaptation of the BS antenna array for maximizing energy efficiency (EE) in downlink of multi-cell multi-user coordinated cellular networks. An iterative algorithm based on fractional programming approach is introduced to solve the...

  10. Boolean network models of cellular regulation: prospects and limitations.

    Science.gov (United States)

    Bornholdt, Stefan

    2008-08-06

    Computer models are valuable tools towards an understanding of the cell's biochemical regulatory machinery. Possible levels of description of such models range from modelling the underlying biochemical details to top-down approaches, using tools from the theory of complex networks. The latter, coarse-grained approach is taken where regulatory circuits are classified in graph-theoretical terms, with the elements of the regulatory networks being reduced to simply nodes and links, in order to obtain architectural information about the network. Further, considering dynamics on networks at such an abstract level seems rather unlikely to match dynamical regulatory activity of biological cells. Therefore, it came as a surprise when recently examples of discrete dynamical network models based on very simplistic dynamical elements emerged which in fact do match sequences of regulatory patterns of their biological counterparts. Here I will review such discrete dynamical network models, or Boolean networks, of biological regulatory networks. Further, we will take a look at such models extended with stochastic noise, which allow studying the role of network topology in providing robustness against noise. In the end, we will discuss the interesting question of why at all such simple models can describe aspects of biology despite their simplicity. Finally, prospects of Boolean models in exploratory dynamical models for biological circuits and their mutants will be discussed.

  11. Cutting the wires: modularization of cellular networks for experimental design

    National Research Council Canada - National Science Library

    Lang, Moritz; Summers, Sean; Stelling, Jörg

    2014-01-01

    .... In this process, initially often simplified and incomplete networks are extended by integrating new reactions or whole subnetworks to increase consistency between model predictions and new measurement data...

  12. Cues for cellular assembly of vascular elastin networks

    Science.gov (United States)

    Kothapalli, Chandrasekhar R.

    Elastin, a structural protein distributed in the extracellular matrix of vascular tissues is critical to the maintenance of vascular mechanics, besides regulation of cell-signaling pathways involved in injury response and morphogenesis. Thus, congenital absence or disease-mediated degradation of vascular elastin and its malformation within native vessels due to innately poor elastin synthesis by adult vascular cells compromise vascular homeostasis. Current elastin regenerative strategies using tissue engineering principles are limited by the progressive destabilization of tropoelastin mRNA expression in adult vascular cells and the unavailability of scaffolds that can provide cellular cues necessary to up-regulate elastin synthesis and regenerate faithful mimics of native elastin. Since our earlier studies demonstrated the elastogenic utility of hyaluronan (HA)-based cues, we have currently sought to identify a unique set of culture conditions based on HA fragments (0.756-2000 kDa), growth factors (TGF-beta1, IGF-1) and other biomolecules (Cu2+ ions, LOX), which will together enhance synthesis, crosslinking, maturation and fibrous elastin matrix formation by adult SMCs, under both healthy and inflammatory conditions. It was observed that TGF-beta1 (1 ng/mL) together with HA oligomers (0.2 microg/mL) synergistically suppressed SMC proliferation, enhanced tropoelastin (8-fold) and matrix elastin synthesis (5.5-fold), besides improving matrix yield (4.5-fold), possibly by increasing production and activity of lysyl oxidase (LOX). Though addition of IGF-1 alone did not offer any advantage, HA fragments (20-200 kDa) in the presence of IGF-1 stimulated tropoelastin and soluble elastin synthesis more than 2.2-fold, with HMW HA contributing for ˜5-fold increase in crosslinked matrix elastin synthesis. Similarly, 0.1 M of Cu2+ ions, alone or together with HA fragments stimulated synthesis of tropoelastin (4-fold) and crosslinked matrix elastin (4.5-fold), via increases in

  13. CCABC: Cyclic Cellular Automata Based Clustering For Energy Conservation in Sensor Networks

    CERN Document Server

    Banerjee, Indrajit; Rahaman, Hafizur

    2011-01-01

    Sensor network has been recognized as the most significant technology for next century. Despites of its potential application, wireless sensor network encounters resource restriction such as low power, reduced bandwidth and specially limited power sources. This work proposes an efficient technique for the conservation of energy in a wireless sensor network (WSN) by forming an effective cluster of the network nodes distributed over a wide range of geographical area. The clustering scheme is developed around a specified class of cellular automata (CA) referred to as the modified cyclic cellular automata (mCCA). It sets a number of nodes in stand-by mode at an instance of time without compromising the area of network coverage and thereby conserves the battery power. The proposed scheme also determines an effective cluster size where the inter-cluster and intra-cluster communication cost is minimum. The simulation results establish that the cyclic cellular automata based clustering for energy conservation in sens...

  14. Linear matrix inequality approach for synchronization control of fuzzy cellular neural networks with mixed time delays

    Institute of Scientific and Technical Information of China (English)

    P. Balasubramaniam; M. Kalpana; R. Rakkiyappan

    2012-01-01

    Fuzzy cellular neural networks (FCNNs) are special kinds of cellular neural networks (CNNs).Each cell in an FCNN contains fuzzy operating abilities.The entire network is governed by cellular computing laws.The design of FCNNs is based on fuzzy local rules.In this paper,a linear matrix inequality (LMI) approach for synchronization control of FCNNs with mixed delays is investigated.Mixed delays include discrete time-varying delays and unbounded distributed delays.A dynamic control scheme is proposed to achieve the synchronization between a drive network and a response network.By constructing the Lyapunov-Krasovskii functional which contains a triple-integral term and the free-weighting matrices method an improved delay-dependent stability criterion is derived in terms of LMIs.The controller can be easily obtained by solving the derived LMIs.A numerical example and its simulations are presented to illustrate the effectiveness of the proposed method.

  15. Modeling virtualized downlink cellular networks with ultra-dense small cells

    KAUST Repository

    Ibrahim, Hazem

    2015-09-11

    The unrelenting increase in the mobile users\\' populations and traffic demand drive cellular network operators to densify their infrastructure. Network densification increases the spatial frequency reuse efficiency while maintaining the signal-to-interference-plus-noise-ratio (SINR) performance, hence, increases the spatial spectral efficiency and improves the overall network performance. However, control signaling in such dense networks consumes considerable bandwidth and limits the densification gain. Radio access network (RAN) virtualization via control plane (C-plane) and user plane (U-plane) splitting has been recently proposed to lighten the control signaling burden and improve the network throughput. In this paper, we present a tractable analytical model for virtualized downlink cellular networks, using tools from stochastic geometry. We then apply the developed modeling framework to obtain design insights for virtualized RANs and quantify associated performance improvement. © 2015 IEEE.

  16. A metabolic-transcriptional network links sleep and cellular energetics in the brain.

    Science.gov (United States)

    Wisor, Jonathan P

    2012-01-01

    This review proposes a mechanistic link between cellular metabolic status, transcriptional regulatory changes and sleep. Sleep loss is associated with changes in cellular metabolic status in the brain. Metabolic sensors responsive to cellular metabolic status regulate the circadian clock transcriptional network. Modifications of the transcriptional activity of circadian clock genes affect sleep/wake state changes. Changes in sleep state reverse sleep loss-induced changes in cellular metabolic status. It is thus proposed that the regulation of circadian clock genes by cellular metabolic sensors is a critical intermediate step in the link between cellular metabolic status and sleep. Studies of this regulatory relationship may offer insights into the function of sleep at the cellular level.

  17. Tools and Models for Integrating Multiple Cellular Networks

    Energy Technology Data Exchange (ETDEWEB)

    Gerstein, Mark [Yale Univ., New Haven, CT (United States). Gerstein Lab.

    2015-11-06

    In this grant, we have systematically investigated the integrated networks, which are responsible for the coordination of activity between metabolic pathways in prokaryotes. We have developed several computational tools to analyze the topology of the integrated networks consisting of metabolic, regulatory, and physical interaction networks. The tools are all open-source, and they are available to download from Github, and can be incorporated in the Knowledgebase. Here, we summarize our work as follow. Understanding the topology of the integrated networks is the first step toward understanding its dynamics and evolution. For Aim 1 of this grant, we have developed a novel algorithm to determine and measure the hierarchical structure of transcriptional regulatory networks [1]. The hierarchy captures the direction of information flow in the network. The algorithm is generally applicable to regulatory networks in prokaryotes, yeast and higher organisms. Integrated datasets are extremely beneficial in understanding the biology of a system in a compact manner due to the conflation of multiple layers of information. Therefore for Aim 2 of this grant, we have developed several tools and carried out analysis for integrating system-wide genomic information. To make use of the structural data, we have developed DynaSIN for protein-protein interactions networks with various dynamical interfaces [2]. We then examined the association between network topology with phenotypic effects such as gene essentiality. In particular, we have organized E. coli and S. cerevisiae transcriptional regulatory networks into hierarchies. We then correlated gene phenotypic effects by tinkering with different layers to elucidate which layers were more tolerant to perturbations [3]. In the context of evolution, we also developed a workflow to guide the comparison between different types of biological networks across various species using the concept of rewiring [4], and Furthermore, we have developed

  18. Simulating Quantitative Cellular Responses Using Asynchronous Threshold Boolean Network Ensembles

    Science.gov (United States)

    With increasing knowledge about the potential mechanisms underlying cellular functions, it is becoming feasible to predict the response of biological systems to genetic and environmental perturbations. Due to the lack of homogeneity in living tissues it is difficult to estimate t...

  19. Rainfall measurement using radio links from cellular communication networks

    NARCIS (Netherlands)

    Leijnse, H.; Uijlenhoet, R.; Stricker, J.N.M.

    2007-01-01

    We investigate the potential of radio links such as employed by commercial cellular communication companies to monitor path-averaged rainfall. We present an analysis of data collected using two 38-GHz links during eight rainfall events over a 2-month period (October¿November 2003) during mostly stra

  20. Dynamic modeling of cellular response to DNA damage based on p53 stress response networks

    Institute of Scientific and Technical Information of China (English)

    Jinpeng Qi; Yongsheng Ding; Shihuang Shao

    2009-01-01

    Under acute perturbations from the outside, cells can trigger self-defensive mechanisms to fight against genome stress. To investigate the cellular response to continuous ion radiation (IR), a dynamic model for p53 stress response networks at the cellular level is proposed. The model can successfully be used to simulate the dynamic processes of double-strand breaks (DSBs) generation and their repair, switch-like ataxia telangiectasia mutated (ATM) activation, oscillations occurring in the p53-MDM2 feedback loop, as well as toxins elimination triggered by p53 stress response networks. Especially, the model can predict the plausible outcomes of cellular response under different IR dose regimes.

  1. Cellular Neural Network-Based Methods for Distributed Network Intrusion Detection

    Directory of Open Access Journals (Sweden)

    Kang Xie

    2015-01-01

    Full Text Available According to the problems of current distributed architecture intrusion detection systems (DIDS, a new online distributed intrusion detection model based on cellular neural network (CNN was proposed, in which discrete-time CNN (DTCNN was used as weak classifier in each local node and state-controlled CNN (SCCNN was used as global detection method, respectively. We further proposed a new method for design template parameters of SCCNN via solving Linear Matrix Inequality. Experimental results based on KDD CUP 99 dataset show its feasibility and effectiveness. Emerging evidence has indicated that this new approach is affordable to parallelism and analog very large scale integration (VLSI implementation which allows the distributed intrusion detection to be performed better.

  2. Spatiotemporal Stochastic Modeling of IoT Enabled Cellular Networks: Scalability and Stability Analysis

    KAUST Repository

    Gharbieh, Mohammad

    2017-05-02

    The Internet of Things (IoT) is large-scale by nature, which is manifested by the massive number of connected devices as well as their vast spatial existence. Cellular networks, which provide ubiquitous, reliable, and efficient wireless access, will play fundamental rule in delivering the first-mile access for the data tsunami to be generated by the IoT. However, cellular networks may have scalability problems to provide uplink connectivity to massive numbers of connected things. To characterize the scalability of cellular uplink in the context of IoT networks, this paper develops a traffic-aware spatiotemporal mathematical model for IoT devices supported by cellular uplink connectivity. The developed model is based on stochastic geometry and queueing theory to account for the traffic requirement per IoT device, the different transmission strategies, and the mutual interference between the IoT devices. To this end, the developed model is utilized to characterize the extent to which cellular networks can accommodate IoT traffic as well as to assess and compare three different transmission strategies that incorporate a combination of transmission persistency, backoff, and power-ramping. The analysis and the results clearly illustrate the scalability problem imposed by IoT on cellular network and offer insights into effective scenarios for each transmission strategy.

  3. Origin of Mobile Cellular Network Technologies and Markets in Germany and China

    Institute of Scientific and Technical Information of China (English)

    Mingtao Shi

    2009-01-01

    The inventive foundation of mobile cellular technologies was laid about 100 years ago. Wireless voice service was Bundespost in the late 1950s and the first analogue cellular network called C-Netz emerged in the mid-1980s. In China, the first mobile cellular networks called TACS-A and TACS-B were installed by Ministry of Post and Telecommunication in the late 1980s. While describing the events in Germany and China, this paper concentrates on discussing the related technologies and their impacts in the marketplace. A comparison summarises some important findings. Japan and Europe's Nordic countries were the first nations to commercialise the I st generation analogous cellular technologies. There existed A-and B-Network in Germany and China, but the network nature of them is quite different. The market development in Germany and China was similar. The enlarged network capacity accommodated gradually more subscribers and prices related to the cellular services fell continuously. However, China's fee system was more complicated and has adopted the RPP regime, while Germany has been using the CPP billing. The article concludes that implications such as the relationship between science and technology, time lag between scientific discovery and technological applications and technology spillover from military to civilian area are the economic lessons learnt from the story of cellular origin.

  4. Networking with noise at the molecular, cellular, and population level

    Science.gov (United States)

    Vilar, Jose

    2002-03-01

    The intrinsic stochastic nature of biochemical reactions affects enzymatic and transcriptional networks at different levels. Yet, cells are able to function effectively and consistently amidst such random fluctuations. I will discuss some molecular mechanisms that are able to reduce the intrinsic noise of chemical reactions, how suitable designs can make networks resistant to noise, and what strategies can be used by populations to achieve precise functions.

  5. Radio resource management in multi-tier cellular wireless networks

    CERN Document Server

    Hossain, Ekram; Niyato, Dusit

    2013-01-01

    Providing an extensive overview of the radio resource management problem in femtocell networks, this invaluable book considers both code division multiple access femtocells and orthogonal frequency-division multiple access femtocells. In addition to incorporating current research on this topic, the book also covers technical challenges in femtocell deployment, provides readers with a variety of approaches to resource allocation and a comparison of their effectiveness, explains how to model various networks using Stochastic geometry and shot noise theory, and much more.

  6. Evaluation of CSSR with Direct TCH Assignment in Cellular Networks

    Directory of Open Access Journals (Sweden)

    Paula Aninyie

    2014-08-01

    Full Text Available Global System for Mobile communication (GSM operators make use of Key Performance Indicators (KPIs to appreciate the network performance and evaluate the Quality of Service (QoS regarding end user perceived quality. KPIs are therefore becoming increasingly important in the context of network rollouts as well as within mature network optimization cycles. The performance of the mobile network is measured based on several counters describing the most important events over a measurement period. The KPIs are derived with the help of these counters using different formulations. Call Setup Success Rate (CSSR is one of the most important KPIs used by all mobile operators. In Ouagadougou, Burkina-Faso, most of the active workers and remote area farmers rely largely on mobile communication services; the GPRS as data services remain highly competitive with GSM voice services. This paper presents a comparative evaluation of theoretically estimated CSSR to measured CSSR data on a real network with regard to GPRS services. The measured data was obtained from the Nokia Siemens Network (NSN statistical tool. The results obtained showed significant improvements in areas where sharp drops in CSSR values were recorded for the measured CSSR. Significantly high R square values of close to 1 representing a high predictive ability from the regression analysis of the estimated CSSR were also recorded. It was concluded that the implementation of the CSSR formulation be extended to CSSR measurements to ensure increased subscriber satisfaction.

  7. Detection of silent cells, synchronization and modulatory activity in developing cellular networks.

    Science.gov (United States)

    Hjorth, Johannes J J; Dawitz, Julia; Kroon, Tim; Pires, Johny; Dassen, Valerie J; Berkhout, Janna A; Emperador Melero, Javier; Nadadhur, Aish G; Alevra, Mihai; Toonen, Ruud F; Heine, Vivi M; Mansvelder, Huibert D; Meredith, Rhiannon M

    2016-04-01

    Developing networks in the immature nervous system and in cellular cultures are characterized by waves of synchronous activity in restricted clusters of cells. Synchronized activity in immature networks is proposed to regulate many different developmental processes, from neuron growth and cell migration, to the refinement of synapses, topographic maps, and the mature composition of ion channels. These emergent activity patterns are not present in all cells simultaneously within the network and more immature "silent" cells, potentially correlated with the presence of silent synapses, are prominent in different networks during early developmental periods. Many current network analyses for detection of synchronous cellular activity utilize activity-based pixel correlations to identify cellular-based regions of interest (ROIs) and coincident cell activity. However, using activity-based correlations, these methods first underestimate or ignore the inactive silent cells within the developing network and second, are difficult to apply within cell-dense regions commonly found in developing brain networks. In addition, previous methods may ignore ROIs within a network that shows transient activity patterns comprising both inactive and active periods. We developed analysis software to semi-automatically detect cells within developing neuronal networks that were imaged using calcium-sensitive reporter dyes. Using an iterative threshold, modulation of activity was tracked within individual cells across the network. The distribution pattern of both inactive and active, including synchronous cells, could be determined based on distance measures to neighboring cells and according to different anatomical layers.

  8. Modeling and Analysis of Cellular Networks using Stochastic Geometry: A Tutorial

    KAUST Repository

    Elsawy, Hesham

    2016-11-03

    This paper presents a tutorial on stochastic geometry (SG) based analysis for cellular networks. This tutorial is distinguished by its depth with respect to wireless communication details and its focus on cellular networks. The paper starts by modeling and analyzing the baseband interference in a baseline single-tier downlink cellular network with single antenna base stations and universal frequency reuse. Then, it characterizes signal-to-interference-plus-noise-ratio (SINR) and its related performance metrics. In particular, a unified approach to conduct error probability, outage probability, and transmission rate analysis is presented. Although the main focus of the paper is on cellular networks, the presented unified approach applies for other types of wireless networks that impose interference protection around receivers. The paper then extends the unified approach to capture cellular network characteristics (e.g., frequency reuse, multiple antenna, power control, etc.). It also presents numerical examples associated with demonstrations and discussions. To this end, the paper highlights the state-of-the- art research and points out future research directions.

  9. Optimized Energy Efficiency and Spectral Efficiency Resource Allocation Strategies for Phantom Cellular Networks

    KAUST Repository

    Abdelhady, Amr, M.

    2016-01-06

    Multi-teir hetrogeneous networks have become an essential constituent for next generation cellular networks. Meanwhile, energy efficiency (EE) has been considered a critical design criterion along with the traditional spectral efficiency (SE) metric. In this context, we study power and spectrum allocation for the recently proposed two-teir architecture known as Phantom cellular networks. The optimization framework includes both EE and SE, where we propose an algorithm that computes the SE and EE resource allocation for Phantom cellular networks. Then, we compare the performance of both design strategies versus the number of users, and the ration of Phantom cellresource blocks to the total number or resource blocks. We aim to investigate the effect of some system parameters to acheive improved SE or EE performance at a non-significant loss in EE or SE performance, respectively. It was found that the system parameters can be tuned so that the EE solution does not yield a significant loss in the SE performance.

  10. Fundamentals of Inter-cell Overhead Signaling in Heterogeneous Cellular Networks

    CERN Document Server

    Xia, Ping; Andrews, Jeffrey G

    2011-01-01

    Heterogeneous base stations (e.g. picocells, microcells, femtocells and distributed antennas) will become increasingly essential for cellular network capacity and coverage. Up until now, little basic research has been done on the fundamentals of managing so much infrastructure -- much of it unplanned -- together with the carefully planned macro-cellular network. Inter-cell coordination is in principle an effective way of ensuring different infrastructure components behave in a way that increases, rather than decreases, the key quality of service (QoS) metrics. The success of such coordination depends heavily on how the overhead is shared, and the rate and delay of the overhead sharing. We develop a novel framework to quantify overhead signaling for inter-cell coordination, which is usually ignored in traditional 1-tier networks, and assumes even more importance in multi-tier heterogeneous cellular networks (HCNs). We derive the overhead quality contour for general K-tier HCNs -- the achievable set of overhead...

  11. Coverage probability of cellular networks using interference alignment under imperfect CSI

    Directory of Open Access Journals (Sweden)

    Raoul F. Guiazon

    2016-11-01

    Full Text Available Interference alignment (IA is well understood to approach the capacity of interference channels, and believed to be crucial in cellular networks in which the ability to control and exploit interference is key. However, the achievable performance of IA in cellular networks depends on the quality of channel state information (CSI and how effective IA is in practical settings is not known. This paper studies the use of IA to mitigate inter-cell interference of cellular networks under imperfect CSI conditions. Our analysis is based on stochastic geometry where the structure of the base station (BS locations is considered by a Poisson point process (PPP. Our main contribution is the coverage probability of the network and simulation results confirm the accuracy.

  12. Retrieval algorithm for rainfall mapping from microwave links in a cellular communication network

    Science.gov (United States)

    Overeem, Aart; Uijlenhoet, Remko; Leijnse, Hidde

    2016-04-01

    Microwave links in commercial cellular communication networks hold a promise for areal rainfall monitoring and could complement rainfall estimates from ground-based weather radars, rain gauges, and satellites. It has been shown that country-wide rainfall maps can be derived from the signal attenuations of microwave links in such a network. We present a rainfall retrieval algorithm, which is employed to obtain rainfall maps from microwave links in a cellular communication network. We compare these rainfall maps to gauge-adjusted radar rainfall maps. The microwave link data set, as well as the developed code, a package in the open source scripting language "R", are freely available at GitHub (https://github.com/overeem11/RAINLINK). The purpose of this presentation is to promote rainfall mapping utilizing microwave links from cellular communication networks as an alternative or complementary means for continental-scale rainfall monitoring.

  13. Channel modeling for fifth generation cellular networks and wireless sensor networks

    Science.gov (United States)

    Torabi, Amir

    In view of exponential growth in data traffic demand, the wireless communications industry has aimed to increase the capacity of existing networks by 1000 times over the next 20 years. A combination of extreme cell densification, more bandwidth, and higher spectral efficiency is needed to support the data traffic requirements for fifth generation (5G) cellular communications. In this research, the potential improvements achieved by using three major 5G enabling technologies (i.e., small cells, millimeter-wave spectrum, and massive MIMO) in rural and urban environments are investigated. This work develops SPM and KA-based ray models to investigate the impact of geometrical parameters on terrain-based multiuser MIMO channel characteristic. Moreover, a new directional 3D channel model is developed for urban millimeter-wave (mmW) small cells. Path-loss, spatial correlation, coverage distance, and coherence length are studied in urban areas. Exploiting physical optics (PO) and geometric optics (GO) solutions, closed form expressions are derived for spatial correlation. Achievable spatial diversity is evaluated using horizontal and vertical linear arrays as well as planar 2D arrays. In another study, a versatile near-ground field prediction model is proposed to facilitate accurate wireless sensor network (WSN) simulations. Monte Carlo simulations are used to investigate the effects of antenna height, frequency of operation, polarization, and terrain dielectric and roughness properties on WSNs performance.

  14. Network-Coded Content Delivery in Femtocaching-Assisted Cellular Networks

    KAUST Repository

    Shnaiwer, Yousef N.

    2015-12-06

    Next-generation cellular networks are expected to be assisted by femtocaches (FCs), which collectively store the most popular files for the clients. Given any arbitrary non-fragmented placement of such files, a strict no-latency constraint, and clients\\' prior knowledge, new file download requests could be efficiently handled by both the FCs and the macrocell base station (MBS) using opportunistic network coding (ONC). In this paper, we aim to find the best allocation of coded file downloads to the FCs so as to minimize the MBS involvement in this download process. We first formulate this optimization problem over an ONC graph, and show that it is NP-hard. We then propose a greedy approach that maximizes the number of files downloaded by the FCs, with the goal to reduce the download share of the MBS. This allocation is performed using a dual conflict ONC graph to avoid conflicts among the FC downloads. Simulations show that our proposed scheme almost achieves the optimal performance and significantly saves on the MBS bandwidth.

  15. From cellular information networks to digital molecular medicine

    Directory of Open Access Journals (Sweden)

    Rafael Rangel-Aldao

    2008-07-01

    participation or even that of healthy individuals in their own care. This so-called P4 medicine (predictive, preventative, personalised and participatory essentially reflects people’s social life in informational biological molecules which are arranged in complex networks following a power law by which very few nodes or hubs made of either genes or their transcription and translation products dominate the entire network through unequal distribution of links or edges. Around one dozen publications of genome-wide association studies (GWAS have shown how the genomic variations of some of these hubs can be applied to predicting the risk of contracting multigenic and common diseases. Moreover, combining GWAS with clinical and metabolic indices of risk significantly improves the power of such techniques for personalised medicine. Key words: Proteome; systems; networks; biotechnology; medicine

  16. Coping with handover effects in video streaming over cellular networks

    Institute of Scientific and Technical Information of China (English)

    BOUAZIZI Imed; HANNUKSELA Miska M.; RAUF Usama

    2006-01-01

    The 3rd generation partnership project (3GPP) has defined the protocols and codecs for implementing media streaming services over packet-switched 3G mobile networks. The specification is based on IETF RFCs on audio/video transport.It also adds new features to achieve better adaptation to the mobile network environment. In this paper, we propose an algorithm for handover detection and fast buffer refill that is based on the existing feedback and signaling mechanisms. The proposed algorithm refills the receiver buffer at a faster pace during a limited time frame after a hard handover is detected in order to achieve higher video quality.

  17. Application of Cellular Automata to Detection of Malicious Network Packets

    Science.gov (United States)

    Brown, Robert L.

    2014-01-01

    A problem in computer security is identification of attack signatures in network packets. An attack signature is a pattern of bits that characterizes a particular attack. Because there are many kinds of attacks, there are potentially many attack signatures. Furthermore, attackers may seek to avoid detection by altering the attack mechanism so that…

  18. Network Asymmetries and Access Pricing in Cellular Telecommunications

    NARCIS (Netherlands)

    V. Kocsis

    2005-01-01

    textabstractNetwork shares and retail prices are not symmetric in the telecommunications market with multiple bottlenecks which give rise to new questions of access fee regulation. In this paper we consider a model with two types of asymmetry arising from different entry timing, i.e. a larger reputa

  19. Application of Cellular Automata to Detection of Malicious Network Packets

    Science.gov (United States)

    Brown, Robert L.

    2014-01-01

    A problem in computer security is identification of attack signatures in network packets. An attack signature is a pattern of bits that characterizes a particular attack. Because there are many kinds of attacks, there are potentially many attack signatures. Furthermore, attackers may seek to avoid detection by altering the attack mechanism so that…

  20. Transient handover blocking probabilities in road covering cellular mobile networks

    NARCIS (Netherlands)

    Boucherie, Richard J.; Wal, van der Jan

    2003-01-01

    This paper investigates handover and fresh call blocking probabilities for subscribers moving along a road in a traffic jam passing through consecutive cells of a wireless network. It is observed and theoretically motivated that the hand- over blocking probabilities show a sharp peak in the initial

  1. Transient handover blocking probabilities in road covering cellular mobile networks

    NARCIS (Netherlands)

    Boucherie, R.J.; Wal, van der J.

    2002-01-01

    This paper investigates handover and fresh call blocking probabilities for subscribers moving along a road in a traffic jam passing through consecutive cells of a wireless network. It is observed and theoretically motivated that the handover blocking probabilities show a sharp peak in the initial pa

  2. Network Asymmetries and Access Pricing in Cellular Telecommunications

    NARCIS (Netherlands)

    V. Kocsis

    2005-01-01

    textabstractNetwork shares and retail prices are not symmetric in the telecommunications market with multiple bottlenecks which give rise to new questions of access fee regulation. In this paper we consider a model with two types of asymmetry arising from different entry timing, i.e. a larger reputa

  3. Reverse engineering cellular decisions for hybrid reconfigurable network modeling

    Science.gov (United States)

    Blair, Howard A.; Saranak, Jureepan; Foster, Kenneth W.

    2011-06-01

    Cells as microorganisms and within multicellular organisms make robust decisions. Knowing how these complex cells make decisions is essential to explain, predict or mimic their behavior. The discovery of multi-layer multiple feedback loops in the signaling pathways of these modular hybrid systems suggests their decision making is sophisticated. Hybrid systems coordinate and integrate signals of various kinds: discrete on/off signals, continuous sensory signals, and stochastic and continuous fluctuations to regulate chemical concentrations. Such signaling networks can form reconfigurable networks of attractors and repellors giving them an extra level of organization that has resilient decision making built in. Work on generic attractor and repellor networks and on the already identified feedback networks and dynamic reconfigurable regulatory topologies in biological cells suggests that biological systems probably exploit such dynamic capabilities. We present a simple behavior of the swimming unicellular alga Chlamydomonas that involves interdependent discrete and continuous signals in feedback loops. We show how to rigorously verify a hybrid dynamical model of a biological system with respect to a declarative description of a cell's behavior. The hybrid dynamical systems we use are based on a unification of discrete structures and continuous topologies developed in prior work on convergence spaces. They involve variables of discrete and continuous types, in the sense of type theory in mathematical logic. A unification such as afforded by convergence spaces is necessary if one wants to take account of the affect of the structural relationships within each type on the dynamics of the system.

  4. On the area spectral efficiency improvement of heterogeneous network by exploiting the integration of macro-femto cellular networks

    KAUST Repository

    Shakir, Muhammad

    2012-06-01

    Heterogeneous networks are an attractive means of expanding mobile network capacity. A heterogeneous network is typically composed of multiple radio access technologies (RATs) where the base stations are transmitting with variable power. In this paper, we consider a Heterogeneous network where we complement the macrocell network with low-power low-cost user deployed nodes, such as femtocell base stations to increase the mean achievable capacity of the system. In this context, we integrate macro-femto cellular networks and derive the area spectral efficiency of the proposed two tier Heterogeneous network. We consider the deployment of femtocell base stations around the edge of the macrocell such that this configuration is referred to as femto-on-edge (FOE) configuration. Moreover, FOE configuration mandates reduction in intercell interference due to the mobile users which are located around the edge of the macrocell since these femtocell base stations are low-power nodes which has significantly lower transmission power than macrocell base stations. We present a mathematical analysis to calculate the instantaneous carrier to interference ratio (CIR) of the desired mobile user in macro and femto cellular networks and determine the total area spectral efficiency of the Heterogeneous network. Details of the simulation processes are included to support the analysis and show the efficacy of the proposed deployment. It has been shown that the proposed setup of the Heterogeneous network offers higher area spectral efficiency which aims to fulfill the expected demand of the future mobile users. © 2012 IEEE.

  5. Logical Modeling and Dynamical Analysis of Cellular Networks.

    Science.gov (United States)

    Abou-Jaoudé, Wassim; Traynard, Pauline; Monteiro, Pedro T; Saez-Rodriguez, Julio; Helikar, Tomáš; Thieffry, Denis; Chaouiya, Claudine

    2016-01-01

    The logical (or logic) formalism is increasingly used to model regulatory and signaling networks. Complementing these applications, several groups contributed various methods and tools to support the definition and analysis of logical models. After an introduction to the logical modeling framework and to several of its variants, we review here a number of recent methodological advances to ease the analysis of large and intricate networks. In particular, we survey approaches to determine model attractors and their reachability properties, to assess the dynamical impact of variations of external signals, and to consistently reduce large models. To illustrate these developments, we further consider several published logical models for two important biological processes, namely the differentiation of T helper cells and the control of mammalian cell cycle.

  6. Novel method for fog monitoring using cellular networks infrastructures

    Science.gov (United States)

    David, N.; Alpert, P.; Messer, H.

    2012-08-01

    A major detrimental effect of fog is visibility limitation which can result in serious transportation accidents, traffic delays and therefore economic damage. Existing monitoring techniques including satellites, transmissometers and human observers - suffer from low spatial resolution, high cost or lack of precision when measuring near ground level. Here we show a novel technique for fog monitoring using wireless communication systems. Communication networks widely deploy commercial microwave links across the terrain at ground level. Operating at frequencies of tens of GHz they are affected by fog and are, effectively, an existing, spatially world-wide distributed sensor network that can provide crucial information about fog concentration and visibility. Fog monitoring potential is demonstrated for a heavy fog event that took place in Israel. The correlation between transmissomters and human eye observations to the visibility estimates from the nearby microwave links was found to be 0.53 and 0.61, respectively. These values indicate the high potential of the proposed method.

  7. Dynamical modeling and analysis of large cellular regulatory networks

    Science.gov (United States)

    Bérenguier, D.; Chaouiya, C.; Monteiro, P. T.; Naldi, A.; Remy, E.; Thieffry, D.; Tichit, L.

    2013-06-01

    The dynamical analysis of large biological regulatory networks requires the development of scalable methods for mathematical modeling. Following the approach initially introduced by Thomas, we formalize the interactions between the components of a network in terms of discrete variables, functions, and parameters. Model simulations result in directed graphs, called state transition graphs. We are particularly interested in reachability properties and asymptotic behaviors, which correspond to terminal strongly connected components (or "attractors") in the state transition graph. A well-known problem is the exponential increase of the size of state transition graphs with the number of network components, in particular when using the biologically realistic asynchronous updating assumption. To address this problem, we have developed several complementary methods enabling the analysis of the behavior of large and complex logical models: (i) the definition of transition priority classes to simplify the dynamics; (ii) a model reduction method preserving essential dynamical properties, (iii) a novel algorithm to compact state transition graphs and directly generate compressed representations, emphasizing relevant transient and asymptotic dynamical properties. The power of an approach combining these different methods is demonstrated by applying them to a recent multilevel logical model for the network controlling CD4+ T helper cell response to antigen presentation and to a dozen cytokines. This model accounts for the differentiation of canonical Th1 and Th2 lymphocytes, as well as of inflammatory Th17 and regulatory T cells, along with many hybrid subtypes. All these methods have been implemented into the software GINsim, which enables the definition, the analysis, and the simulation of logical regulatory graphs.

  8. Cellular metabolic network analysis: discovering important reactions in Treponema pallidum.

    Science.gov (United States)

    Chen, Xueying; Zhao, Min; Qu, Hong

    2015-01-01

    T. pallidum, the syphilis-causing pathogen, performs very differently in metabolism compared with other bacterial pathogens. The desire for safe and effective vaccine of syphilis requests identification of important steps in T. pallidum's metabolism. Here, we apply Flux Balance Analysis to represent the reactions quantitatively. Thus, it is possible to cluster all reactions in T. pallidum. By calculating minimal cut sets and analyzing topological structure for the metabolic network of T. pallidum, critical reactions are identified. As a comparison, we also apply the analytical approaches to the metabolic network of H. pylori to find coregulated drug targets and unique drug targets for different microorganisms. Based on the clustering results, all reactions are further classified into various roles. Therefore, the general picture of their metabolic network is obtained and two types of reactions, both of which are involved in nucleic acid metabolism, are found to be essential for T. pallidum. It is also discovered that both hubs of reactions and the isolated reactions in purine and pyrimidine metabolisms play important roles in T. pallidum. These reactions could be potential drug targets for treating syphilis.

  9. Limits on the Capacity of In-Band Full Duplex Communication in Uplink Cellular Networks

    KAUST Repository

    Randrianantenaina, Itsikiantsoa

    2016-02-26

    Simultaneous co-channel transmission and reception, denoted as in-band full duplex (FD) communication, has been promoted as an attractive solution to improve the spectral efficiency of cellular networks. However, in addition to the selfinterference problem, cross-mode interference (i.e., between uplink and downlink) imposes a major obstacle for the deployment of FD communication in cellular networks. More specifically, the downlink to uplink interference represents the performance bottleneck for FD operation due to the uplink limited transmission power and venerable operation when compared to the downlink counterpart. While the positive impact of FD communication to the downlink performance has been proved in the literature, its effect on the uplink transmission has been neglected. This paper focuses on the effect of downlink interference on the uplink transmission in FD cellular networks in order to see whether FD communication is beneficial for the uplink transmission or not, and if yes for which type of network. To quantify the expected performance gains, we derive a closed form expression of the maximum achievable uplink capacity in FD cellular networks. In contrast to the downlink capacity which always improves with FD communication, our results show that the uplink performance may improves or degrades depending on the associated network parameters. Particularly, we show that the intensity of base stations (BSs) has a more prominent effect on the uplink performance than their transmission power.

  10. Cellular network entropy as the energy potential in Waddington's differentiation landscape.

    Science.gov (United States)

    Banerji, Christopher R S; Miranda-Saavedra, Diego; Severini, Simone; Widschwendter, Martin; Enver, Tariq; Zhou, Joseph X; Teschendorff, Andrew E

    2013-10-24

    Differentiation is a key cellular process in normal tissue development that is significantly altered in cancer. Although molecular signatures characterising pluripotency and multipotency exist, there is, as yet, no single quantitative mark of a cellular sample's position in the global differentiation hierarchy. Here we adopt a systems view and consider the sample's network entropy, a measure of signaling pathway promiscuity, computable from a sample's genome-wide expression profile. We demonstrate that network entropy provides a quantitative, in-silico, readout of the average undifferentiated state of the profiled cells, recapitulating the known hierarchy of pluripotent, multipotent and differentiated cell types. Network entropy further exhibits dynamic changes in time course differentiation data, and in line with a sample's differentiation stage. In disease, network entropy predicts a higher level of cellular plasticity in cancer stem cell populations compared to ordinary cancer cells. Importantly, network entropy also allows identification of key differentiation pathways. Our results are consistent with the view that pluripotency is a statistical property defined at the cellular population level, correlating with intra-sample heterogeneity, and driven by the degree of signaling promiscuity in cells. In summary, network entropy provides a quantitative measure of a cell's undifferentiated state, defining its elevation in Waddington's landscape.

  11. Cellular network entropy as the energy potential in Waddington's differentiation landscape

    Science.gov (United States)

    Banerji, Christopher R. S.; Miranda-Saavedra, Diego; Severini, Simone; Widschwendter, Martin; Enver, Tariq; Zhou, Joseph X.; Teschendorff, Andrew E.

    2013-10-01

    Differentiation is a key cellular process in normal tissue development that is significantly altered in cancer. Although molecular signatures characterising pluripotency and multipotency exist, there is, as yet, no single quantitative mark of a cellular sample's position in the global differentiation hierarchy. Here we adopt a systems view and consider the sample's network entropy, a measure of signaling pathway promiscuity, computable from a sample's genome-wide expression profile. We demonstrate that network entropy provides a quantitative, in-silico, readout of the average undifferentiated state of the profiled cells, recapitulating the known hierarchy of pluripotent, multipotent and differentiated cell types. Network entropy further exhibits dynamic changes in time course differentiation data, and in line with a sample's differentiation stage. In disease, network entropy predicts a higher level of cellular plasticity in cancer stem cell populations compared to ordinary cancer cells. Importantly, network entropy also allows identification of key differentiation pathways. Our results are consistent with the view that pluripotency is a statistical property defined at the cellular population level, correlating with intra-sample heterogeneity, and driven by the degree of signaling promiscuity in cells. In summary, network entropy provides a quantitative measure of a cell's undifferentiated state, defining its elevation in Waddington's landscape.

  12. Protease-associated cellular networks in malaria parasite Plasmodium falciparum

    Directory of Open Access Journals (Sweden)

    Lilburn Timothy G

    2011-12-01

    Full Text Available Abstract Background Malaria continues to be one of the most severe global infectious diseases, responsible for 1-2 million deaths yearly. The rapid evolution and spread of drug resistance in parasites has led to an urgent need for the development of novel antimalarial targets. Proteases are a group of enzymes that play essential roles in parasite growth and invasion. The possibility of designing specific inhibitors for proteases makes them promising drug targets. Previously, combining a comparative genomics approach and a machine learning approach, we identified the complement of proteases (degradome in the malaria parasite Plasmodium falciparum and its sibling species 123, providing a catalog of targets for functional characterization and rational inhibitor design. Network analysis represents another route to revealing the role of proteins in the biology of parasites and we use this approach here to expand our understanding of the systems involving the proteases of P. falciparum. Results We investigated the roles of proteases in the parasite life cycle by constructing a network using protein-protein association data from the STRING database 4, and analyzing these data, in conjunction with the data from protein-protein interaction assays using the yeast 2-hybrid (Y2H system 5, blood stage microarray experiments 678, proteomics 9101112, literature text mining, and sequence homology analysis. Seventy-seven (77 out of 124 predicted proteases were associated with at least one other protein, constituting 2,431 protein-protein interactions (PPIs. These proteases appear to play diverse roles in metabolism, cell cycle regulation, invasion and infection. Their degrees of connectivity (i.e., connections to other proteins, range from one to 143. The largest protease-associated sub-network is the ubiquitin-proteasome system which is crucial for protein recycling and stress response. Proteases are also implicated in heat shock response, signal peptide

  13. Novel Stochastic Model for Call Admission Control in Broadband Wireless Multimedia Networks

    Institute of Scientific and Technical Information of China (English)

    LIUGan; ZHUGuangxi; RUANYoulin; HUZhenping; WUWeimin; WANGDesheng

    2005-01-01

    As the increasing demand of the capacity of cellular networks, the cell sizes have become smaller than ever, which increases the probability of handoff one may experience during a service. To ensure the calls, QoS and high channel utilization, an effective call admission control is needed urgently. The well-known Guard channel method (GCM) which works with static fashion cannotadapt to the changes in traffic pattern, whereas, SDCA mechanism proposed by S. Wu can overcome that shortcoming due to its dynamic nature. Unfortunately, it is only suitable for single-service. In this paper, we establish a novel stochastic model to study the actual system so as to avoid coping with the complex multiple dimensions stochastic problem. Two wonderful features of the model make it competent for this role. On one hand, it can turnthe multiple steps of state transition into single step ofstate transition, which is a necessary condition for ideal birth-death processes. On the other hand, it can providea simple method to compute the approximation of the call dropping probabilities for multiple services, which facilitate our estimation for the acceptance ratio vector subject to QoS requirement. As a result, we get a multi-services dynamic call admission scheme to adapt for multiple types of services in mobile wireless networks. Numerical results show that our scheme steadily satisfies the constraint on call dropping probability of multi-services while maintaining a high channel throughput.

  14. Energy Cost Minimization in Heterogeneous Cellular Networks with Hybrid Energy Supplies

    Directory of Open Access Journals (Sweden)

    Bang Wang

    2016-01-01

    Full Text Available The ever increasing data demand has led to the significant increase of energy consumption in cellular mobile networks. Recent advancements in heterogeneous cellular networks and green energy supplied base stations provide promising solutions for cellular communications industry. In this article, we first review the motivations and challenges as well as approaches to address the energy cost minimization problem for such green heterogeneous networks. Owing to the diversities of mobile traffic and renewable energy, the energy cost minimization problem involves both temporal and spatial optimization of resource allocation. We next present a new solution to illustrate how to combine the optimization of the temporal green energy allocation and spatial mobile traffic distribution. The whole optimization problem is decomposed into four subproblems, and correspondingly our proposed solution is divided into four parts: energy consumption estimation, green energy allocation, user association, and green energy reallocation. Simulation results demonstrate that our proposed algorithm can significantly reduce the total energy cost.

  15. Reliable Multicasting for Device-to-Device Radio Underlaying Cellular Networks

    CERN Document Server

    Yang, Wei; Li, Lihua

    2010-01-01

    This paper proposes Leader in Charge (LiC), a reliable multicast architecture for device-to-device (D2D) radio underlaying cellular networks. The multicast-requesting user equipments (UEs) in close proximity form a D2D cluster to receive the multicast packets through cooperation. In addition to receiving the multicast packets from the eNB, UEs share what they received from the multicast on short-range links among UEs, namely the D2D links, to exploit the wireless resources a more efficient way. Consequently, we show that utilizing the D2D links in cellular networks increases the throughput of a multicast session by means of simulation. We also discuss some practical issues facing the integration of LiC into the current cellular networks. In particular, we propose efficient delay control mechanism to reduce the average and maximum delay experienced by LiC users, which is further confirmed by the simulation results.

  16. DS-CDMA system outer loop power control and improvement for multi-service

    Institute of Scientific and Technical Information of China (English)

    Guan Mingxiang; Guo Qing; Li Xing

    2008-01-01

    When a new user accesses the CDMA system, the load will change drastically, and therefore, the advanced outer loop power control (OLPC) technology has to be adopted to enrich the target signal interference ratio (SIR) and improve the system performance. The existing problems about DS-CDMA outer loop power control for multi-service are introduced and the power control theoretical model is analyzed. System simulation is adopted on how to obtain the theoretical performance and parameter optimization of the power control algorithm. The OLPC algorithm is improved and the performance comparisons between the old algorithm and the improved algorithm are given. The results show good performance of the improved OLPC algorithm and prove the validity of the improved method for multi-service.

  17. EVOLUTION OF WIRELESS MOBILE COMMUNICATION NETWORKS AND FUTURE OF CELLULAR MARKET IN INDIA

    Directory of Open Access Journals (Sweden)

    Arjun Kondur

    2012-10-01

    Full Text Available In this paper, we discuss the evolution of the mobile communication systems from GSM to LTE (2G to 4G and the trends in the mobile communication industry. The Global System for Mobile Communication (GSM is a well established cellular system targeted here due to its engineering success and the large number of users currently using the services. The flexibility of wireless networks over voice and data transmission makes it one of the most popular modes of communication. Evolution to next generation services depends on an addition of new services and new features to the existing networks or even an integration of different communication technologies. With the invention of the devices such as tablets and smart phones the need to improve the data transmission rates and transmission efficiency has increased to higher than ever before. In this paper, we focus at some of the important issues pertaining to the evolution of mobile communication networks and predict the future of the networks based on the analysis of the cellular market in India. Since GSM networks accounts for more than 75% of the world wide cellular network, only the evolution of GSM network has been discussed in this paper.

  18. GLOBAL STABILITY ANALYSIS IN CELLULAR NEURAL NETWORKS WITH UNBOUNDED TIME DELAYS

    Institute of Scientific and Technical Information of China (English)

    张继业

    2004-01-01

    Without assuming the boundedness and differentiability of the activation functions,the conditions ensuring existence,uniqueness,and global asymptotical stability of the equilibrium point of cellular neural networks with unbounded time delays and variable delays were studied.Using the idea of vector Liapunov method,the intero-differential inequalities with unbounded delay and variable delays were constructed.By the stability analysis of the intero-differential inequalities,the sufficient conditions for global asymptotic stability of cellular neural networks were obtained.

  19. Cooperative device-to-device communication in cognitive radio cellular networks

    CERN Document Server

    Li, Peng

    2014-01-01

    This brief examines current research on cooperative device-to-device (D2D) communication as an enhanced offloading technology to improve the performance of cognitive radio cellular networks. By providing an extensive review of recent advances in D2D communication, the authors demonstrate that the quality of D2D links significantly affects offloading performance in cellular networks, which motivates the design of cooperative D2D communication. After presenting the architecture of cooperative D2D communication, the challenges of capacity maximization and energy efficiency are addressed by optimi

  20. Exploring Spatio-temporal Dynamics of Cellular Automata for Pattern Recognition in Networks

    Science.gov (United States)

    Miranda, Gisele Helena Barboni; Machicao, Jeaneth; Bruno, Odemir Martinez

    2016-11-01

    Network science is an interdisciplinary field which provides an integrative approach for the study of complex systems. In recent years, network modeling has been used for the study of emergent phenomena in many real-world applications. Pattern recognition in networks has been drawing attention to the importance of network characterization, which may lead to understanding the topological properties that are related to the network model. In this paper, the Life-Like Network Automata (LLNA) method is introduced, which was designed for pattern recognition in networks. LLNA uses the network topology as a tessellation of Cellular Automata (CA), whose dynamics produces a spatio-temporal pattern used to extract the feature vector for network characterization. The method was evaluated using synthetic and real-world networks. In the latter, three pattern recognition applications were used: (i) identifying organisms from distinct domains of life through their metabolic networks, (ii) identifying online social networks and (iii) classifying stomata distribution patterns varying according to different lighting conditions. LLNA was compared to structural measurements and surpasses them in real-world applications, achieving improvement in the classification rate as high as 23%, 4% and 7% respectively. Therefore, the proposed method is a good choice for pattern recognition applications using networks and demonstrates potential for general applicability.

  1. Efficient Resource Scheduling by Exploiting Relay Cache for Cellular Networks

    Directory of Open Access Journals (Sweden)

    Chun He

    2015-01-01

    Full Text Available In relay-enhanced cellular systems, throughput of User Equipment (UE is constrained by the bottleneck of the two-hop link, backhaul link (or the first hop link, and access link (the second hop link. To maximize the throughput, resource allocation should be coordinated between these two hops. A common resource scheduling algorithm, Adaptive Distributed Proportional Fair, only ensures that the throughput of the first hop is greater than or equal to that of the second hop. But it cannot guarantee a good balance of the throughput and fairness between the two hops. In this paper, we propose a Two-Hop Balanced Distributed Scheduling (TBS algorithm by exploiting relay cache for non-real-time data traffic. The evolved Node Basestation (eNB adaptively adjusts the number of Resource Blocks (RBs allocated to the backhaul link and direct links based on the cache information of relays. Each relay allocates RBs for relay UEs based on the size of the relay UE’s Transport Block. We also design a relay UE’s ACK feedback mechanism to update the data at relay cache. Simulation results show that the proposed TBS can effectively improve resource utilization and achieve a good trade-off between system throughput and fairness by balancing the throughput of backhaul and access link.

  2. Mitochondria: the cellular hub of the dynamic coordinated network.

    Science.gov (United States)

    Yin, Fei; Cadenas, Enrique

    2015-04-20

    Mitochondria are the powerhouses of the eukaryotic cell. After billions of years of evolution, mitochondria have adaptively integrated into the symbiont. Such integration is not only evidenced by the consolidation of genetic information, that is, the transfer of most mitochondrial genes into the nucleus, but also manifested by the functional recombination by which mitochondria participate seamlessly in various cellular processes. In the past decade, the field of mitochondria biology has been focused on the dynamic and interactive features of these semiautonomous organelles. Aspects of a complex multilayer quality control system coordinating mitochondrial function and environmental changes are being uncovered and refined. This Forum summarizes the recent progress of these critical topics, with a focus on the dynamic quality control of mitochondrial reticulum, including their biogenesis, dynamic remodeling, and degradation, as well as the homeostasis of the mitochondrial proteome. These diverse but interconnected mechanisms are found to be critical in the maintenance of a functional, efficient, and responsive mitochondrial population and could therefore become therapeutic targets in numerous mitochondrion-implicated disorders.

  3. Spinal cellular and network properties modulate pain perception

    Directory of Open Access Journals (Sweden)

    Darbon Pascal

    2016-01-01

    Previously, it has been shown that high levels of plasma glucocorticoids give rise to analgesia. However to our knowledge nothing has been reported regarding a direct non genomic modulation of neuronal spinal activity by peripheral CORT. In the present study, we used combined in vivo and in vitro electrophysiology approaches, associated with the measure of nociceptive mechanical sensitivity and plasma corticosterone level measurement to assess the impact of circulating CORT on rat nociception. We showed that CORT plasma level elevation produced analgesia via the reduction of nociceptive fiber mediated spinal responses. CORT is spinally reduced in the neuroactive metabolite THDOC that specifically enhances lamina II GABAergic synaptic transmission. The main consequence is a reduction of lamina II network excitability reflecting a selective decrease in processing of nociceptive inputs. The depressed neuronal activity at the spinal level then in turn leads to a weaker nociceptive message transmission to supraspinal structures and hence to an alleviation of pain.

  4. Least dissipation cost as a design principle for robustness and function of cellular networks

    Science.gov (United States)

    Han, Bo; Wang, Jin

    2008-03-01

    From a study of the budding yeast cell cycle, we found that the cellular network evolves to have the least cost for realizing its biological function. We quantify the cost in terms of the dissipation or heat loss characterized through the steady-state properties: the underlying landscape and the associated flux. We found that the dissipation cost is intimately related to the stability and robustness of the network. With the least dissipation cost, the network becomes most stable and robust under mutations and perturbations on the sharpness of the response from input to output as well as self-degradations. The least dissipation cost may provide a general design principle for the cellular network to survive from the evolution and realize the biological function.

  5. Multi-operator collaboration for green cellular networks under roaming price consideration

    KAUST Repository

    Ghazzai, Hakim

    2014-09-01

    This paper investigates the collaboration between multiple mobile operators to optimize the energy efficiency of cellular networks. Our framework studies the case of LTE-Advanced networks deployed in the same area and owning renewable energy generators. The objective is to reduce the CO2 emissions of cellular networks via collaborative techniques and using base station sleeping strategy while respecting the network quality of service. Low complexity and practical algorithm is employed to achieve green goals during low traffic periods. Cooperation decision criteria are also established basing on derived roaming prices and profit gains of competitive mobile operators. Our numerical results show a significant save in terms of CO2 compared to the non-collaboration case and that cooperative mobile operator exploiting renewables are more awarded than traditional operators.

  6. Bayesian approaches to reverse engineer cellular systems: a simulation study on nonlinear Gaussian networks

    Directory of Open Access Journals (Sweden)

    Ramoni Marco F

    2007-05-01

    Full Text Available Abstract Background Reverse engineering cellular networks is currently one of the most challenging problems in systems biology. Dynamic Bayesian networks (DBNs seem to be particularly suitable for inferring relationships between cellular variables from the analysis of time series measurements of mRNA or protein concentrations. As evaluating inference results on a real dataset is controversial, the use of simulated data has been proposed. However, DBN approaches that use continuous variables, thus avoiding the information loss associated with discretization, have not yet been extensively assessed, and most of the proposed approaches have dealt with linear Gaussian models. Results We propose a generalization of dynamic Gaussian networks to accommodate nonlinear dependencies between variables. As a benchmark dataset to test the new approach, we used data from a mathematical model of cell cycle control in budding yeast that realistically reproduces the complexity of a cellular system. We evaluated the ability of the networks to describe the dynamics of cellular systems and their precision in reconstructing the true underlying causal relationships between variables. We also tested the robustness of the results by analyzing the effect of noise on the data, and the impact of a different sampling time. Conclusion The results confirmed that DBNs with Gaussian models can be effectively exploited for a first level analysis of data from complex cellular systems. The inferred models are parsimonious and have a satisfying goodness of fit. Furthermore, the networks not only offer a phenomenological description of the dynamics of cellular systems, but are also able to suggest hypotheses concerning the causal interactions between variables. The proposed nonlinear generalization of Gaussian models yielded models characterized by a slightly lower goodness of fit than the linear model, but a better ability to recover the true underlying connections between

  7. Global exponential stability of mixed discrete and distributively delayed cellular neural network

    Institute of Scientific and Technical Information of China (English)

    Yao Hong-Xing; Zhou Jia-Yan

    2011-01-01

    This paper concernes analysis for the global exponential stability of a class of recurrent neural networks with mixed discrete and distributed delays. It first proves the existence and uniqueness of the balance point, then by employing the Lyapunov-Krasovskii functional and Young inequality, it gives the sufficient condition of global exponential stability of cellular neural network with mixed discrete and distributed delays, in addition, the example is provided to illustrate the applicability of the result.

  8. Characterization of one-dimensional cellular automata rules through topological network features

    Science.gov (United States)

    D'Alotto, Lou; Pizzuti, Clara

    2016-10-01

    The paper investigates the relationship between the classification schemes, defined by Wolfram and Gilman, of one-dimensional cellular automata through concepts coming from network theory. An automaton is represented with a network, generated from the elementary rule defining its behavior. Characteristic features of this graph are computed and machine learning classification models are built. Such models allow to classify automaton rules and to compare Wolfram's and Gilman's classes by comparing the classes predicted by these models.

  9. Energy-Efficient Resource Allocation for Phantom Cellular Networks with Imperfect CSI

    KAUST Repository

    Abdelhady, Amr

    2017-03-28

    Multi-tier heterogeneous networks have become an essential constituent for next generation cellular networks. Meanwhile, energy efficiency (EE) has been considered a critical design criterion along with the traditional spectral efficiency (SE) metric. In this context, we study power and spectrum allocation for a two-tier phantom cellular network, The optimization framework includes both EE and SE. We consider densely deployed phantom cellular networks and model the EE optimization problem taking into consideration the inevitable interference in this setup and imperfect channel estimation impairments. To this end, we propose three resource allocation strategies aiming at optimizing this network EE performance metric. Furthermore, we investigate the effect of changing some system parameters on the performance of these strategies, such as phantom cells resource units share, number of deployed phantom cells within a macro cell , number of pilots, and the phantom cells transmission power budget. It is found that increasing the number of pilots will deteriorate the EE performance of the whole setup, while increasing phantom cells transmission power budget will not affect the EE of the whole setup significantly. In addition, we observed that it is always useful to allocate most of the network resource units to the phantom cells tier.

  10. A mathematical model to study the dynamics of epithelial cellular networks.

    Science.gov (United States)

    Abate, Alessandro; Vincent, Stéphane; Dobbe, Roel; Silletti, Alberto; Master, Neal; Axelrod, Jeffrey D; Tomlin, Claire J

    2012-01-01

    Epithelia are sheets of connected cells that are essential across the animal kingdom. Experimental observations suggest that the dynamical behavior of many single-layered epithelial tissues has strong analogies with that of specific mechanical systems, namely large networks consisting of point masses connected through spring-damper elements and undergoing the influence of active and dissipating forces. Based on this analogy, this work develops a modeling framework to enable the study of the mechanical properties and of the dynamic behavior of large epithelial cellular networks. The model is built first by creating a network topology that is extracted from the actual cellular geometry as obtained from experiments, then by associating a mechanical structure and dynamics to the network via spring-damper elements. This scalable approach enables running simulations of large network dynamics: the derived modeling framework in particular is predisposed to be tailored to study general dynamics (for example, morphogenesis) of various classes of single-layered epithelial cellular networks. In this contribution, we test the model on a case study of the dorsal epithelium of the Drosophila melanogaster embryo during early dorsal closure (and, less conspicuously, germband retraction).

  11. On mode selection and power control for uplink D2D communication in cellular networks

    KAUST Repository

    Ali, Konpal S.

    2015-06-08

    Device-to-device (D2D) communication enables users lying in close proximity to bypass the cellular base station (BS) and transmit to one another directly. This offloads traffic from the cellular network, improves spatial frequency reuse and energy efficiency in the network. We present a comprehensive and tractable analytical framework for D2D-enabled uplink cellular networks with two different flexible mode-selection schemes. The power-control cutoff thresholds of the two communication modes have been decoupled unlike past work on the subject. We find that for a given network, an optimal value exists not only for the biased mode selection criterion, but also for r, the ratio of the power-control cutoff thresholds of the two communication modes, which maximizes spatial spectral efficiency. Also, r turns out to be a more robust parameter for optimizing network performance. Further, it is shown that the second scheme, which prioritizes spatial frequency reuse over the per-user achievable performance compared to the first scheme, achieves almost the same overall network performance; thereby trading per user performance to serve a larger number of users.

  12. Assessing the implications of cellular network performance on mobile content access

    DEFF Research Database (Denmark)

    Kaup, Fabian; Michelinakis, Foivos; Bui, Nicola

    2016-01-01

    that the association of mobile devices to a point of presence (PoP) within the operator's network can influence the end-to-end performance by a large extent. Given the collected data, a model predicting the PoP assignment and its resulting RTT leveraging Markov chain and machine learning approaches is developed. RTT......Mobile applications such as VoIP, (live) gaming, or video streaming have diverse QoS requirements ranging from low delay to high throughput. The optimization of the network quality experienced by end-users requires detailed knowledge of the expected network performance. Also, the achieved service...... quality is affected by a number of factors, including network operator and available technologies. However, most studies measuring the cellular network do not consider the performance implications of network configuration and management. To this end, this paper reports about an extensive data set...

  13. Downlink Performance of a Multi-Carrier MIMO System in a Bursty Traffic Cellular Network

    DEFF Research Database (Denmark)

    Nguyen, Hung Tuan; Kovacs, Istvan; Wang, Yuanye

    2011-01-01

    In this paper we analyse the downlink performance of a rank adaptive multiple input multiple output (MIMO) system in a busty traffic cellular network. A LTE-Advanced system with multiple component carriers was selected as a study case. To highlight the advantage of using MIMO techniques, we used...

  14. Almost periodic solution of shunting inhibitory cellular neural networks with time-varying delay

    Energy Technology Data Exchange (ETDEWEB)

    Huang Xia; Cao Jinde

    2003-07-28

    Several sufficient conditions are obtained for the existence of almost periodic solution and its attractivity of shunting inhibitory cellular neural networks with time-varying delay based on the fixed point method and Halanay inequality technique. Some previous results are improved and extended in this Letter and two examples are given to illustrate the effectiveness of the new results.

  15. Retrieval algorithm for rainfall mapping from microwave links in a cellular communication network

    NARCIS (Netherlands)

    Overeem, Aart; Leijnse, Hidde; Uijlenhoet, Remko

    2016-01-01

    Microwave links in commercial cellular communication networks hold a promise for areal rainfall monitoring and could complement rainfall estimates from ground-based weather radars, rain gauges, and satellites. It has been shown that country-wide (≈ 35 500 km2) 15 min rainfall maps can

  16. Optimizing the morphological design of discrete-time cellular neural networks

    NARCIS (Netherlands)

    terBrugge, MH; Spaanenburg, L; Jansen, WJ; Nijhuis, JAG

    1996-01-01

    The morphological design of Discrete-Time Cellular Neural Networks (DTCNNs) has been presented in a companion paper [1]. DTCNN templates have been given for the elemental morphological operators. One way to obtain realizations for more complex operators is cascading the DTCNN equivalences of the

  17. Optically controlled reconfigurable antenna for 5G future broadband cellular communication networks

    DEFF Research Database (Denmark)

    Costa, I.F. da; Spadoti, D. H.; Cerqueira Sodre Jr., Arismar

    2017-01-01

    the lightly licensed 28 GHz and 38 GHz frequency bands, useful for future mobile 5G broadband cellular communication networks. Experimental results with the reconfigurable antenna on 16-QAM and 32-QAM wireless transmission supported by photonic downconversion are successfully reported under 78 dB link budget...

  18. Radio resource management for mobile traffic offloading in heterogeneous cellular networks

    CERN Document Server

    Wu, Yuan; Huang, Jianwei; Shen, Xuemin (Sherman)

    2017-01-01

    This SpringerBrief offers two concrete design examples for traffic offloading. The first is an optimal resource allocation for small-cell based traffic offloading that aims at minimizing mobile users’ data cost. The second is an optimal resource allocation for device-to-device assisted traffic offloading that also minimizes the total energy consumption and cellular link usage (while providing an overview of the challenging issues). Both examples illustrate the importance of proper resource allocation to the success of traffic offloading, show the consequent performance advantages of executing optimal resource allocation, and present the methodologies to achieve the corresponding optimal offloading solution for traffic offloading in heterogeneous cellular networks. The authors also include an overview of heterogeneous cellular networks and explain different traffic offloading paradigms ranging from uplink traffic offloading through small cells to downlink traffic offloading via mobile device-to-device cooper...

  19. Power Control for D2D Underlay Cellular Networks with Imperfect CSI

    KAUST Repository

    Memmi, Amen

    2017-02-09

    Device-to-Device communications underlying the cellular infrastructure is a technology that has recently been proposed as a promising solution to enhance cellular network capabilities. However, interference is the major challenge since the same resources are shared by both systems. Therefore, interference management techniques are required to keep the interference under control. In this work, in order to mitigate interference, we consider centralized and distributed power control algorithms in a one-cell random network model. Differently from previous works, we are assuming that the channel state information may be imperfect and include estimation errors. We evaluate how this uncertainty impacts performances. In the centralized approach, we derive the optimal powers that maximize the coverage probability and the rate of the cellular user while scheduling as many D2D links as possible. These powers are computed at the base station (BS) and then delivered to the users, and hence the name

  20. Cooperative Game-Based Energy Efficiency Management over Ultra-Dense Wireless Cellular Networks

    Directory of Open Access Journals (Sweden)

    Ming Li

    2016-09-01

    Full Text Available Ultra-dense wireless cellular networks have been envisioned as a promising technique for handling the explosive increase of wireless traffic volume. With the extensive deployment of small cells in wireless cellular networks, the network spectral efficiency (SE is improved with the use of limited frequency. However, the mutual inter-tier and intra-tier interference between or among small cells and macro cells becomes serious. On the other hand, more chances for potential cooperation among different cells are introduced. Energy efficiency (EE has become one of the most important problems for future wireless networks. This paper proposes a cooperative bargaining game-based method for comprehensive EE management in an ultra-dense wireless cellular network, which highlights the complicated interference influence on energy-saving challenges and the power-coordination process among small cells and macro cells. Especially, a unified EE utility with the consideration of the interference mitigation is proposed to jointly address the SE, the deployment efficiency (DE, and the EE. In particular, closed-form power-coordination solutions for the optimal EE are derived to show the convergence property of the algorithm. Moreover, a simplified algorithm is presented to reduce the complexity of the signaling overhead, which is significant for ultra-dense small cells. Finally, numerical simulations are provided to illustrate the efficiency of the proposed cooperative bargaining game-based and simplified schemes.

  1. Cooperative Game-Based Energy Efficiency Management over Ultra-Dense Wireless Cellular Networks.

    Science.gov (United States)

    Li, Ming; Chen, Pengpeng; Gao, Shouwan

    2016-09-13

    Ultra-dense wireless cellular networks have been envisioned as a promising technique for handling the explosive increase of wireless traffic volume. With the extensive deployment of small cells in wireless cellular networks, the network spectral efficiency (SE) is improved with the use of limited frequency. However, the mutual inter-tier and intra-tier interference between or among small cells and macro cells becomes serious. On the other hand, more chances for potential cooperation among different cells are introduced. Energy efficiency (EE) has become one of the most important problems for future wireless networks. This paper proposes a cooperative bargaining game-based method for comprehensive EE management in an ultra-dense wireless cellular network, which highlights the complicated interference influence on energy-saving challenges and the power-coordination process among small cells and macro cells. Especially, a unified EE utility with the consideration of the interference mitigation is proposed to jointly address the SE, the deployment efficiency (DE), and the EE. In particular, closed-form power-coordination solutions for the optimal EE are derived to show the convergence property of the algorithm. Moreover, a simplified algorithm is presented to reduce the complexity of the signaling overhead, which is significant for ultra-dense small cells. Finally, numerical simulations are provided to illustrate the efficiency of the proposed cooperative bargaining game-based and simplified schemes.

  2. Resource allocation for phantom cellular networks: Energy efficiency vs spectral efficiency

    KAUST Repository

    Abdelhady, Amr M.

    2016-07-26

    Multi-tier heterogeneous networks have become an essential constituent for next generation cellular networks. Mean-while, energy efficiency (EE) has been considered a critical design criterion along with the traditional spectral efficiency (SE) metric. In this context, we study power and spectrum allocation for the recently proposed two-tier network architecture known as phantom cellular networks. The optimization framework includes both EE and SE, where we propose an algorithm that finds the SE and EE resource allocation strategies for phantom cellular networks. Then, we compare the performance of both design strategies versus the number of users, and phantom cells share of the total number of available resource blocks. We aim to investigate the effect of some system parameters to achieve improved SE performance at a non-significant loss in EE performance, or vice versa. It was found that increasing phantom cells share of resource blocks decreases the SE performance loss due to EE optimization when compared with the optimized SE performance. © 2016 IEEE.

  3. Cooperative Game-Based Energy Efficiency Management over Ultra-Dense Wireless Cellular Networks

    Science.gov (United States)

    Li, Ming; Chen, Pengpeng; Gao, Shouwan

    2016-01-01

    Ultra-dense wireless cellular networks have been envisioned as a promising technique for handling the explosive increase of wireless traffic volume. With the extensive deployment of small cells in wireless cellular networks, the network spectral efficiency (SE) is improved with the use of limited frequency. However, the mutual inter-tier and intra-tier interference between or among small cells and macro cells becomes serious. On the other hand, more chances for potential cooperation among different cells are introduced. Energy efficiency (EE) has become one of the most important problems for future wireless networks. This paper proposes a cooperative bargaining game-based method for comprehensive EE management in an ultra-dense wireless cellular network, which highlights the complicated interference influence on energy-saving challenges and the power-coordination process among small cells and macro cells. Especially, a unified EE utility with the consideration of the interference mitigation is proposed to jointly address the SE, the deployment efficiency (DE), and the EE. In particular, closed-form power-coordination solutions for the optimal EE are derived to show the convergence property of the algorithm. Moreover, a simplified algorithm is presented to reduce the complexity of the signaling overhead, which is significant for ultra-dense small cells. Finally, numerical simulations are provided to illustrate the efficiency of the proposed cooperative bargaining game-based and simplified schemes. PMID:27649170

  4. Identification of driving network of cellular differentiation from single sample time course gene expression data

    Science.gov (United States)

    Chen, Ye; Wolanyk, Nathaniel; Ilker, Tunc; Gao, Shouguo; Wang, Xujing

    Methods developed based on bifurcation theory have demonstrated their potential in driving network identification for complex human diseases, including the work by Chen, et al. Recently bifurcation theory has been successfully applied to model cellular differentiation. However, there one often faces a technical challenge in driving network prediction: time course cellular differentiation study often only contains one sample at each time point, while driving network prediction typically require multiple samples at each time point to infer the variation and interaction structures of candidate genes for the driving network. In this study, we investigate several methods to identify both the critical time point and the driving network through examination of how each time point affects the autocorrelation and phase locking. We apply these methods to a high-throughput sequencing (RNA-Seq) dataset of 42 subsets of thymocytes and mature peripheral T cells at multiple time points during their differentiation (GSE48138 from GEO). We compare the predicted driving genes with known transcription regulators of cellular differentiation. We will discuss the advantages and limitations of our proposed methods, as well as potential further improvements of our methods.

  5. Heterogeneous Cellular Networks with Flexible Cell Association: A Comprehensive Downlink SINR Analysis

    CERN Document Server

    Jo, Han-Shin; Xia, Ping; Andrews, Jeffrey G

    2011-01-01

    In this paper we develop a tractable framework for SINR analysis in downlink heterogeneous cellular networks (HCNs) with flexible cell association policies. The HCN is modeled as a multi-tier cellular network where each tier's base stations (BSs) are randomly located and have a particular transmit power, path loss exponent, spatial density, and bias towards admitting mobile users. For example, as compared to macrocells, picocells would usually have lower transmit power, higher path loss exponent (lower antennas), higher spatial density (many picocells per macrocell), and a positive bias so that macrocell users are actively encouraged to use the more lightly loaded picocells. In the present paper we implicitly assume all base stations have full queues; future work should relax this. For this model, we derive the outage probability of a typical user in the whole network or a certain tier, which is equivalently the downlink SINR cumulative distribution function. The results are accurate for all SINRs, and their ...

  6. A self-learning call admission control scheme for CDMA cellular networks.

    Science.gov (United States)

    Liu, Derong; Zhang, Yi; Zhang, Huaguang

    2005-09-01

    In the present paper, a call admission control scheme that can learn from the network environment and user behavior is developed for code division multiple access (CDMA) cellular networks that handle both voice and data services. The idea is built upon a novel learning control architecture with only a single module instead of two or three modules in adaptive critic designs (ACDs). The use of adaptive critic approach for call admission control in wireless cellular networks is new. The call admission controller can perform learning in real-time as well as in offline environments and the controller improves its performance as it gains more experience. Another important contribution in the present work is the choice of utility function for the present self-learning control approach which makes the present learning process much more efficient than existing learning control methods. The performance of our algorithm will be shown through computer simulation and compared with existing algorithms.

  7. Retrieval algorithm for rainfall mapping from microwave links in a cellular communication network

    Science.gov (United States)

    Overeem, A.; Leijnse, H.; Uijlenhoet, R.

    2015-08-01

    Microwave links in commercial cellular communication networks hold a promise for areal rainfall monitoring and could complement rainfall estimates from ground-based weather radars, rain gauges, and satellites. It has been shown that country-wide rainfall maps can be derived from the signal attenuations of microwave links in such a network. Here we give a detailed description of the employed rainfall retrieval algorithm and provide the corresponding code. Moreover, the code (in the scripting language "R") is made available including a data set of commercial microwave links. The purpose of this paper is to promote rainfall monitoring utilizing microwave links from cellular communication networks as an alternative or complementary means for global, continental-scale rainfall monitoring.

  8. Network analysis of oyster transcriptome revealed a cascade of cellular responses during recovery after heat shock.

    Directory of Open Access Journals (Sweden)

    Lingling Zhang

    Full Text Available Oysters, as a major group of marine bivalves, can tolerate a wide range of natural and anthropogenic stressors including heat stress. Recent studies have shown that oysters pretreated with heat shock can result in induced heat tolerance. A systematic study of cellular recovery from heat shock may provide insights into the mechanism of acquired thermal tolerance. In this study, we performed the first network analysis of oyster transcriptome by reanalyzing microarray data from a previous study. Network analysis revealed a cascade of cellular responses during oyster recovery after heat shock and identified responsive gene modules and key genes. Our study demonstrates the power of network analysis in a non-model organism with poor gene annotations, which can lead to new discoveries that go beyond the focus on individual genes.

  9. The Digital Age of Mobile Cellular Network in Germany and China :Policies, Technologies and Markets (PartⅠ)

    Institute of Scientific and Technical Information of China (English)

    Mingtao Shi

    2009-01-01

    The German Postal Reform Ⅰ in 1989 introduced competition in the mobile cellular market. German cellular operators, DeTeMobil, Mannesmann, E-Plus and VIAG Interkom, built DI-, D2-, El- and E2-Netze based on GSM standards made in Europe. China Unicom was created in 1994 and China Telecom was separated from MPT in 1995. China Telecom and China Unicorn competed in a duopoly from the mid-1990s onwards and the cellular services provided by them also rely on GSM standards. China Telecom additionally deployed XLT technology (PHS) from the late 1990s onwards. While DeTeMobil and Mannesmarm conquered approximately 80%-90% of the market throughout the 1990s and were the two dominant market players in Germany, China's cellular market was mainly controlled by China Mobile. In Germany, prices related to cellular technology continued the downwards trend as a major result of the process of deregulation, liberalisation and competition. In China, price wars bad led to significant price reductions in the cellular market. Although network operators in both countries strived to deliver differentiated cellular Services, the two national markets in the 1990s were visibly shaped by product homogeneity.

  10. Optimization of Cellular Resources Evading Intra and Inter Tier Interference in Femto cells Equipped Macro cell Networks

    CERN Document Server

    Shakhakarmi, Niraj

    2012-01-01

    Cellular network resources are essential to be optimized in Femto cells equipped macro cell networks. This is achieved by increasing the cellular coverage and channel capacity, and reducing power usage and interference between femto cells and macro cells. In this paper, the optimization approach for cellular resources with installed femto cells in macro cell networks has been addressed by deploying smart antennas applications and effect power adaptation method which significantly optimize the cellular coverage, channel capacity, power usage, and intra and inter tier interference. The simulation results also illustrate the outstanding performance of this optimization methodology.

  11. Quantum complexity: Quantum mutual information, complex networks, and emergent phenomena in quantum cellular automata

    Science.gov (United States)

    Vargas, David L.

    Emerging quantum simulator technologies provide a new challenge to quantum many body theory. Quantifying the emergent order in and predicting the dynamics of such complex quantum systems requires a new approach. We develop such an approach based on complex network analysis of quantum mutual information. First, we establish the usefulness of quantum mutual information complex networks by reproducing the phase diagrams of transverse Ising and Bose-Hubbard models. By quantifying the complexity of quantum cellular automata we then demonstrate the applicability of complex network theory to non-equilibrium quantum dynamics. We conclude with a study of student collaboration networks, correlating a student's role in a collaboration network with their grades. This work thus initiates a quantitative theory of quantum complexity and provides a new tool for physics education research. (Abstract shortened by ProQuest.).

  12. Management of Location Based Advertisement Services using Spatial Triggers in Cellular Networks

    CERN Document Server

    Irfan, M; Khan, Furqan H; Hashmi, Raheel M; Shehzad, Khurram; Ali, Assad

    2009-01-01

    This paper discusses the advent of new technologies which have emerged under the area of Location Based Services (LBS). An innovative implementation and approach has been presented for design of applications which are inventive and attractive towards the user. Spatial Trigger is one of the most promising additions to the LBS technologies. This paper describes ways in which mobile advertisement services can be introduced effectively in the cellular market by bringing innovation in them through effective usage of Spatial Triggers. Hence, opening new horizons to make the consumer cellular networks, commercially, more effective and informative.

  13. A Tabu Search DSA Algorithm for Reward Maximization in Cellular Networks

    OpenAIRE

    Kamal, Hany; Coupechoux, Marceau; Godlewski, Philippe

    2010-01-01

    International audience; In this paper, we present and analyze a Tabu Search (TS) algorithm for DSA (Dynamic Spectrum Access) in cellular networks. We study a mono-operator case where the operator is providing packet services to the end-users. The objective of the cellular operator is to maximize its reward while taking into account the trade-off between the spectrum cost and the revenues obtained from end-users. These revenue are modeled here as an increasing function of the achieved throughp...

  14. Management of Location Based Advertisement Services using Spatial Triggers in Cellular Networks

    Directory of Open Access Journals (Sweden)

    Assad Ali

    2009-10-01

    Full Text Available This paper discusses the advent of new technologies which have emerged under the area of Location Based Services (LBS. An innovative implementation and approach has been presented for design of applications which are inventive and attractive towards the user. Spatial Trigger is one of the most promising additions to the LBS technologies. This paper describes ways in which mobile advertisement services can be introduced effectively in the cellular market by bringing innovation in them through effective usage of Spatial Triggers. Hence, opening new horizons to make the consumer cellular networks, commercially, more effective and informative.

  15. Performance Evaluation of 5G Millimeter-Wave Cellular Access Networks Using a Capacity-Based Network Deployment Tool

    Directory of Open Access Journals (Sweden)

    Michel Matalatala

    2017-01-01

    Full Text Available The next fifth generation (5G of wireless communication networks comes with a set of new features to satisfy the demand of data-intensive applications: millimeter-wave frequencies, massive antenna arrays, beamforming, dense cells, and so forth. In this paper, we investigate the use of beamforming techniques through various architectures and evaluate the performance of 5G wireless access networks, using a capacity-based network deployment tool. This tool is proposed and applied to a realistic area in Ghent, Belgium, to simulate realistic 5G networks that respond to the instantaneous bit rate required by the active users. The results show that, with beamforming, 5G networks require almost 15% more base stations and 4 times less power to provide more capacity to the users and the same coverage performances, in comparison with the 4G reference network. Moreover, they are 3 times more energy efficient than the 4G network and the hybrid beamforming architecture appears to be a suitable architecture for beamforming to be considered when designing a 5G cellular network.

  16. Next-Generation Environment-Aware Cellular Networks: Modern Green Techniques and Implementation Challenges

    KAUST Repository

    Ghazzai, Hakim

    2016-09-16

    Over the last decade, mobile communications have been witnessing a noteworthy increase of data traffic demand that is causing an enormous energy consumption in cellular networks. The reduction of their fossil fuel consumption in addition to the huge energy bills paid by mobile operators is considered as the most important challenges for the next-generation cellular networks. Although most of the proposed studies were focusing on individual physical layer power optimizations, there is a growing necessity to meet the green objective of fifth-generation cellular networks while respecting the user\\'s quality of service. This paper investigates four important techniques that could be exploited separately or together in order to enable wireless operators achieve significant economic benefits and environmental savings: 1) the base station sleeping strategy; 2) the optimized energy procurement from the smart grid; 3) the base station energy sharing; and 4) the green networking collaboration between competitive mobile operators. The presented simulation results measure the gain that could be obtained using these techniques compared with that of traditional scenarios. Finally, this paper discusses the issues and challenges related to the implementations of these techniques in real environments. © 2016 IEEE.

  17. PV-Powered CoMP-Based Green Cellular Networks with a Standby Grid Supply

    Directory of Open Access Journals (Sweden)

    Abu Jahid

    2017-01-01

    Full Text Available This paper proposes a novel framework for PV-powered cellular networks with a standby grid supply and an essential energy management technique for achieving envisaged green networks. The proposal considers an emerging cellular network architecture employing two types of coordinated multipoint (CoMP transmission techniques for serving the subscribers. Under the proposed framework, each base station (BS is powered by an individual PV solar energy module having an independent storage device. BSs are also connected to the conventional grid supply for meeting additional energy demand. We also propose a dynamic inter-BS solar energy sharing policy through a transmission line for further greening the proposed network by minimizing the consumption from the grid supply. An extensive simulation-based study in the downlink of a Long-Term Evolution (LTE cellular system is carried out for evaluating the energy efficiency performance of the proposed framework. System performance is also investigated for identifying the impact of various system parameters including storage factor, storage capacity, solar generation capacity, transmission line loss, and different CoMP techniques.

  18. GAME THEORY BASED INTERFERENCE CONTROL AND POWER CONTROL FOR D2D COMMUNICATION IN CELLULAR NETWORKS

    Directory of Open Access Journals (Sweden)

    Fa-Bin Li

    2016-09-01

    Full Text Available With the current development of mobile communication services, people need personal communication of high speed, excellent service, high quality and low latency,however, limited spectrum resources become the most important factor to hamper improvement of cellular systems. As big amount of data traffic will cause greater local consumption of spectrum resources, future networks are required to have appropriate techniques to better support such forms of communication. D2D (Device-to-device communication technology in a cellular network makes full use of spectrum resources underlaying, reduces the load of the base station, minimizes transmit power of the terminals and the base stations, thereby enhances the overall throughput of the networks. Due to the use of multiplexing D2D UE (User equipment resources and spectrum, and the interference caused by the sharing of resources between adjacent cells, it has become a major factor affecting coexisting of cellular subscribers and D2D users. When D2D communication multiplexes the uplink resources, the base-stations are easily to be disturbed; when the downlink resources are multiplexed, the users of downlink are susceptible to interference. In order to build a high-efficient mobile network, we can meet the QoS requirements by controlling the power to suppress the interference between the base station and a terminal user.

  19. A Biologically-Inspired Power Control Algorithm for Energy-Efficient Cellular Networks

    Directory of Open Access Journals (Sweden)

    Hyun-Ho Choi

    2016-03-01

    Full Text Available Most of the energy used to operate a cellular network is consumed by a base station (BS, and reducing the transmission power of a BS can therefore afford a substantial reduction in the amount of energy used in a network. In this paper, we propose a distributed transmit power control (TPC algorithm inspired by bird flocking behavior as a means of improving the energy efficiency of a cellular network. Just as each bird in a flock attempts to match its velocity with the average velocity of adjacent birds, in the proposed algorithm, each mobile station (MS in a cell matches its rate with the average rate of the co-channel MSs in adjacent cells by controlling the transmit power of its serving BS. We verify that this bio-inspired TPC algorithm using a local rate-average process achieves an exponential convergence and maximizes the minimum rate of the MSs concerned. Simulation results show that the proposed TPC algorithm follows the same convergence properties as the flocking algorithm and also effectively reduces the power consumption at the BSs while maintaining a low outage probability as the inter-cell interference increases; in so doing, it significantly improves the energy efficiency of a cellular network.

  20. INVESTIGATION OF UPLINK RADIO RESOURCE MANAGEMENT SCHEMES FOR MULTI-SERVICES IN TDD-CDMA SYSTEMS EMPLOYING SMART ANTENNAS

    Institute of Scientific and Technical Information of China (English)

    Peng Mugen; Wang Wenbo

    2006-01-01

    In this paper, a theoretical analysis of Time Division Duplex-Code Division Multiple Access (TDD-CDMA) uplink capacity constraint is presented when employing the smart antenna techniques. The evaluation formulations of capacity and load for multi-services are proposed. In order to maximize the throughput, the objective of optimization is proposed, and an advanced uplink resource management algorithm is developed. The proposed algorithm based on the least interference admission control scheme focuses on the maximum throughput for the circuit switched multi-services. The simulation results show that the proposed strategy has a significant improvement in throughput when the optimum admission control threshold is set.

  1. An Integrated Framework to Model Cellular Phenotype as a Component of Biochemical Networks

    Directory of Open Access Journals (Sweden)

    Michael Gormley

    2011-01-01

    Full Text Available Identification of regulatory molecules in signaling pathways is critical for understanding cellular behavior. Given the complexity of the transcriptional gene network, the relationship between molecular expression and phenotype is difficult to determine using reductionist experimental methods. Computational models provide the means to characterize regulatory mechanisms and predict phenotype in the context of gene networks. Integrating gene expression data with phenotypic data in transcriptional network models enables systematic identification of critical molecules in a biological network. We developed an approach based on fuzzy logic to model cell budding in Saccharomyces cerevisiae using time series expression microarray data of the cell cycle. Cell budding is a phenotype of viable cells undergoing division. Predicted interactions between gene expression and phenotype reflected known biological relationships. Dynamic simulation analysis reproduced the behavior of the yeast cell cycle and accurately identified genes and interactions which are essential for cell viability.

  2. Joint Mode Selection and Resource Allocation for Cellular Controlled Short-Range Communication in OFDMA Networks

    Science.gov (United States)

    Deng, Hui; Tao, Xiaoming; Ge, Ning; Lu, Jianhua

    This letter studies cellular controlled short-range communication in OFDMA networks. The network needs to decide when to allow direct communication between a closely located device-to-device (D2D) pair instead of conveying data from one device to the other via the base station and when not to, in addition to subchannel and power allocation. Our goal is to maximize the total network throughput while guaranteeing the rate requirements of all users. For that purpose, we formulate an optimization problem subject to subchannel and power constraints. A scheme which combines a joint mode selection and subchannel allocation algorithm based on equal power allocation with a power reallocation scheme is proposed. Simulation results show that our proposed scheme can improve the network throughput and outage probability compared with other schemes.

  3. Optimization Framework and Graph-Based Approach for Relay-Assisted Bidirectional OFDMA Cellular Networks

    CERN Document Server

    Liu, Yuan; Li, Bin; Shen, Hui

    2010-01-01

    This paper considers a relay-assisted bidirectional cellular network where the base station (BS) communicates with each mobile station (MS) using OFDMA for both uplink and downlink. The goal is to improve the overall system performance by exploring the full potential of the network in various dimensions including user, subcarrier, relay, and bidirectional traffic. In this work, we first introduce a novel three-time-slot time-division duplexing (TDD) transmission protocol. This protocol unifies direct transmission, one-way relaying and network-coded two-way relaying between the BS and each MS. Using the proposed three-time-slot TDD protocol, we then propose an optimization framework for resource allocation to achieve the following gains: cooperative diversity (via relay selection), network coding gain (via bidirectional transmission mode selection), and multiuser diversity (via subcarrier assignment). We formulate the problem as a combinatorial optimization problem, which is NP-complete. To make it more tracta...

  4. Application of GA in optimization of pore network models generated by multi-cellular growth algorithms

    Science.gov (United States)

    Jamshidi, Saeid; Boozarjomehry, Ramin Bozorgmehry; Pishvaie, Mahmoud Reza

    2009-10-01

    In pore network modeling, the void space of a rock sample is represented at the microscopic scale by a network of pores connected by throats. Construction of a reasonable representation of the geometry and topology of the pore space will lead to a reliable prediction of the properties of porous media. Recently, the theory of multi-cellular growth (or L-systems) has been used as a flexible tool for generation of pore network models which do not require any special information such as 2D SEM or 3D pore space images. In general, the networks generated by this method are irregular pore network models which are inherently closer to the complicated nature of the porous media rather than regular lattice networks. In this approach, the construction process is controlled only by the production rules that govern the development process of the network. In this study, genetic algorithm has been used to obtain the optimum values of the uncertain parameters of these production rules to build an appropriate irregular lattice network capable of the prediction of both static and hydraulic information of the target porous medium.

  5. A Categorized Resource Sharing Mechanism for Device-to-Device Communications in Cellular Networks

    Directory of Open Access Journals (Sweden)

    Jie Chen

    2016-01-01

    Full Text Available Device-to-Device (D2D communications are considered one of the key technologies for 5G wireless communication systems. In this paper, a resource sharing mechanism, which applies different policies for different cases (thus being categorized, is proposed. In this scheme, all D2D pairs are divided into three groups by comparing the minimum transmit power with the maximum transmit power of each cellular UE. The proposed mechanism enables multiple D2D pairs in the second group to share the resource with cellular user equipment (UE simultaneously, by adjusting the transmit powers of these D2D transmitters. At the same time, D2D pairs in the first group and the third group share resource with cellular UE based on the transmit power minimization principle. Simulation results show that the proposed scheme can achieve relatively higher network throughput and lower transmit power consumption of the D2D system.

  6. Application of neural networks to channel assignment for cellular CDMA networks with multiple services and mobile base stations

    Science.gov (United States)

    Hortos, William S.

    1996-03-01

    The use of artificial neural networks to the channel assignment problem for cellular code- division multiple access (CDMA) telecommunications systems is considered. CDMA takes advantage of voice activity and spatial isolation because its capacity is only interference limited, unlike time-division multiple access (TDMA) and frequency-division multiple access (FDMA) where capacities are bandwidth limited. Any reduction in interference in CDMA translates linearly into increased capacity. FDMA and TDMA use a frequency reuse pattern as a method to increase capacity, while CDMA reuses the same frequency for all cells and gains a reuse efficiency by means of orthogonal codes. The latter method can improve system capacity by factors of four to six over digital TDMA or FDMA. Cellular carriers are planning to provide multiple communication services using CDMA in the next generation cellular system infrastructure. The approach of this study is the use of neural network methods for automatic and local network control, based on traffic behavior in specific cell cites and demand history. The goal is to address certain problems associated with the management of mobile and personal communication services in a cellular radio communications environment. In planning a cellular radio network, the operator assigns channels to the radio cells so that the probability of the processed carrier-to-interference ratio, CII, exceeding a predefined value is sufficiently low. The RF propagation, determined from the topography and infrastructure in the operating area, is used in conjunction with the densities of expected communications traffic to formulate interference constraints. These constraints state which radio cells may use the same code (channel) or adjacent channels at a time. The traffic loading and the number of service grades can also be used to calculate the number of required channels (codes) for each cell. The general assignment problem is the task of assigning the required number

  7. Cellular Controlled Short-Range Communication for Cooperative P2P Networking

    DEFF Research Database (Denmark)

    Fitzek, Frank H. P.; Katz, Marcos; Zhang, Qi

    2009-01-01

    This article advocates a novel communication architecture and associated collaborative framework for future wireless communication systems. In contrast to the dominating cellular architecture and the upcoming peer-to-peer architecture, the new approach envisions a cellular controlled short......-range communication network among cooperating mobile and wireless devices. The role of the mobile device will change, from being an agnostic entity in respect to the surrounding world to a cognitive device. This cognitive device is capable of being aware of the neighboring devices as well as on the possibility...... to establish cooperation with them. The novel architecture together with several possible cooperative strategies will bring clear benefits for the network and service providers, mobile device manufacturers and also end users....

  8. In-Band Full-Duplex Communications for Cellular Networks with Partial Uplink/Downlink Overlap

    KAUST Repository

    AlAmmouri, Ahmad

    2015-12-06

    In-band full-duplex (FD) communications have been optimistically promoted to improve the spectrum utilization in cellular networks. However, the explicit impact of spatial interference, imposed by FD communications, on uplink and downlink transmissions has been overlooked in the literature. This paper presents an extensive study of the explicit effect of FD communications on the uplink and downlink performances. For the sake of rigorous analysis, we develop a tractable framework based on stochastic geometry toolset. The developed model accounts for uplink truncated channel inversion power control in FD cellular networks. The study shows that FD communications improve the downlink throughput at the expense of significant degradation in the uplink throughput. Therefore, we propose a novel fine-grained duplexing scheme, denoted as α-duplex scheme, which allows a partial overlap between uplink and downlink frequency bands. To this end, we show that the amount of the overlap can be optimized via adjusting α to achieve a certain design objective.

  9. The Influence of Gaussian Signaling Approximation on Error Performance in Cellular Networks

    KAUST Repository

    Afify, Laila H.

    2015-08-18

    Stochastic geometry analysis for cellular networks is mostly limited to outage probability and ergodic rate, which abstracts many important wireless communication aspects. Recently, a novel technique based on the Equivalent-in-Distribution (EiD) approach is proposed to extend the analysis to capture these metrics and analyze bit error probability (BEP) and symbol error probability (SEP). However, the EiD approach considerably increases the complexity of the analysis. In this paper, we propose an approximate yet accurate framework, that is also able to capture fine wireless communication details similar to the EiD approach, but with simpler analysis. The proposed methodology is verified against the exact EiD analysis in both downlink and uplink cellular networks scenarios.

  10. Device-to-Device Underlay Cellular Networks with Uncertain Channel State Information

    KAUST Repository

    Memmi, Amen

    2016-01-06

    Device-to-Device (D2D) communications underlying the cellular infrastructure is a technology that has recently been proposed as a promising solution to enhance cellular network capabilities: It improves spectrum utilization, overall throughput and energy efficiency while enabling new peer-to-peer and location-based applications and services. However, interference is the major challenge since the same resources are shared by both systems. Therefore, interference management techniques are required to keep the interference under control. In this work, in order to mitigate interference, we consider centralized and distributed power control algorithms in a one-cell random network model. Differently from previous works, we are assuming that the channel state information (CSI) may be imperfect and include estimation errors. We evaluate how this uncertainty impacts performances.

  11. Optimal planning for cellular networks for smart metering infrastructure in rural and remote areas

    Directory of Open Access Journals (Sweden)

    Andrés Masache

    2015-07-01

    Full Text Available Smart metering is used to control, monitor and know the system status in real time; to this effect, the incorporation of smart grids primarily benefits the electrical system; similarly, the reuse of infrastructure and cellular spectrum help mitigate the time and cost of its implementation. In order to reduce traffic and saturation of cellular networks, this paper aims at determining the optimal route for information transmission analyzing the optimal routing through distances and optimal routing through traffic flow. This analysis helps determine what the optimal route is, when there is no traffic on the wireless network, or when there is prolonged traffic, and what the traffic tendencies are, that may occur by excessive information transmission of smart meters to electric distribution companies.

  12. Sensitivity analysis of FBMC-based multi-cellular networks to synchronization errors and HPA nonlinearities

    Science.gov (United States)

    Elmaroud, Brahim; Faqihi, Ahmed; Aboutajdine, Driss

    2017-01-01

    In this paper, we study the performance of asynchronous and nonlinear FBMC-based multi-cellular networks. The considered system includes a reference mobile perfectly synchronized with its reference base station (BS) and K interfering BSs. Both synchronization errors and high-power amplifier (HPA) distortions will be considered and a theoretical analysis of the interference signal will be conducted. On the basis of this analysis, we will derive an accurate expression of signal-to-noise-plus-interference ratio (SINR) and bit error rate (BER) in the presence of a frequency-selective channel. In order to reduce the computational complexity of the BER expression, we applied an interesting lemma based on the moment generating function of the interference power. Finally, the proposed model is evaluated through computer simulations which show a high sensitivity of the asynchronous FBMC-based multi-cellular network to HPA nonlinear distortions.

  13. A new cellular nonlinear network emulation on FPGA for EEG signal processing in epilepsy

    Science.gov (United States)

    Müller, Jens; Müller, Jan; Tetzlaff, Ronald

    2011-05-01

    For processing of EEG signals, we propose a new architecture for the hardware emulation of discrete-time Cellular Nonlinear Networks (DT-CNN). Our results show the importance of a high computational accuracy in EEG signal prediction that cannot be achieved with existing analogue VLSI circuits. The refined architecture of the processing elements and its resource schedule, the cellular network structure with local couplings, the FPGA-based embedded system containing the DT-CNN, and the data flow in the entire system will be discussed in detail. The proposed DT-CNN design has been implemented and tested on an Xilinx FPGA development platform. The embedded co-processor with a multi-threading kernel is utilised for control and pre-processing tasks and data exchange to the host via Ethernet. The performance of the implemented DT-CNN has been determined for a popular example and compared to that of a conventional computer.

  14. Velocity-Aware Handover Management in Two-Tier Cellular Networks

    KAUST Repository

    Arshad, Rabe

    2017-01-19

    While network densification is considered an important solution to cater the ever-increasing capacity demand, its effect on the handover (HO) rate is overlooked. In dense 5G networks, HO delays may neutralize or even negate the gains offered by network densification. Hence, user mobility imposes a nontrivial challenge to harvest capacity gains via network densification. In this paper, we propose a velocity-aware HO management scheme for two-tier downlink cellular network to mitigate the HO effect on the foreseen densification throughput gains. The proposed HO scheme sacrifices the best base station (BS) connectivity, by skipping HO to some BSs along the user trajectory, to maintain longer connection durations and reduce HO rates. Furthermore, the proposed scheme enables cooperative BS service and strongest interference cancellation to compensate for skipping the best connectivity. To this end, we consider different HO skipping scenarios and develop a velocity-aware mathematical model, via stochastic geometry, to quantify the performance of the proposed HO schemes in terms of the coverage probability and user throughput. The results highlight the HO rate problem in dense cellular environments and show the importance of the proposed HO schemes. Finally, the value of BS cooperation along with handover skipping is quantified for different user mobility profiles.

  15. An analytical model for evaluating outage and handover probability of cellular wireless networks

    CERN Document Server

    Decreusefond, Laurent; Vu, Than-Tung

    2010-01-01

    We consider stochastic cellular networks where base stations locations form a homogenous Poisson point process and each mobile is attached to the base station that provides the best mean signal power. The mobile is in outage if the SINR falls below some threshold. The handover decision has to be made if the mobile is in outage for some time slots. The outage probability and the handover probability is evaluated in taking into account the effect of path loss, shadowing, Rayleigh fast fading, frequency factor reuse and conventional beamforming. The main assumption is that the Rayleigh fast fading changes each time slot while other network components remain static during the period of study.

  16. One-way hash function based on hyper-chaotic cellular neural network

    Institute of Scientific and Technical Information of China (English)

    Yang Qun-Ting; Gao Tie-Gang

    2008-01-01

    The design of an efficient one-way hash function with good performance is a hot spot in modern cryptography researches. In this paper, a hash function construction method based on cell neural network with hyper-chaos characteristics is proposed. First, the chaos sequence is gotten by iterating cellular neural network with Runge-Kutta algorithm, and then the chaos sequence is iterated with the message. The hash code is obtained through the corresponding transform of the latter chaos sequence. Simulation and analysis demonstrate that the new method has the merit of convenience, high sensitivity to initial values, good hash performance, especially the strong stability.

  17. Admission Control Scheme for Multi-class Services in QoS-based Mobile Cellular Networks

    Institute of Scientific and Technical Information of China (English)

    YINZhiming; XIEJianying

    2004-01-01

    Call admission control (CAC) is one of the key schemes to guarantee Quality of service (QoS) in mobile cellular networks. In this paper, we propose an optimal CAC scheme based on Semi-Markov decision processes (SMDP) theory to support multi-class services for QoS wireless networks. Linear programming formulation is used to find the optimal solution, which maximizes the channel utilization while meeting the requirements of QoS constraints. The numerical results show that the performance of our scheme outperforms DCAC scheme.

  18. The Effect of Spatial Interference Correlation and Jamming on Secrecy in Cellular Networks

    KAUST Repository

    Ali, Konpal Shaukat

    2017-06-02

    Recent studies on secure wireless communication have shed light on a scenario where interference has a desirable impact on network performance. Particularly, assuming independent interference-power fluctuations at the eavesdropper and the receiver, opportunistic secure-information transfer can occur on the legitimate-link. However, interference is spatially correlated due to the common set of interfering sources, which may diminish the opportunistic-secure-spectrum-access (OSSA) probability. We study and quantify the effect of spatial interference correlation on OSSA in cellular-networks and investigate the potential of full-duplex jamming (FDJ) solutions. The results highlight the scenarios where FDJ improves OSSA performance.

  19. On the Impact of Mobility on Outage Probability in Cellular Networks

    OpenAIRE

    Kélif, Jean-Marc; Coupechoux, Marceau

    2009-01-01

    International audience; In this paper, we develop an analytical study of the mobility in cellular networks and its impact on quality of service and outage probability. We first express analytically the downlink other-cell interference factor f by using a fluid model network. It is defined here as the ratio of outer cell received power to the inner cell received power. It allows us to analyze users mobility and to derive expressions of the outage probability. We show that mobility can modify t...

  20. Analytical modeling of mode selection and power control for underlay D2D communication in cellular networks

    KAUST Repository

    Elsawy, Hesham

    2014-11-01

    Device-to-device (D2D) communication enables the user equipments (UEs) located in close proximity to bypass the cellular base stations (BSs) and directly connect to each other, and thereby, offload traffic from the cellular infrastructure. D2D communication can improve spatial frequency reuse and energy efficiency in cellular networks. This paper presents a comprehensive and tractable analytical framework for D2D-enabled uplink cellular networks with a flexible mode selection scheme along with truncated channel inversion power control. The developed framework is used to analyze and understand how the underlaying D2D communication affects the cellular network performance. Through comprehensive numerical analysis, we investigate the expected performance gains and provide guidelines for selecting the network parameters.

  1. Exponential stability of cellular neural networks with multiple time delays and impulsive effects

    Institute of Scientific and Technical Information of China (English)

    Li Dong; Wang Hui; Yang Dan; Zhang Xiao-Hong; Wang Shi-Long

    2008-01-01

    In this work,the stability issues of the equilibrium points of the cellular neural networks with multiple time delays and impulsive effects are investigated.Based on the stability theory of Lyapunov-Krasovskii,the method of linear matrix inequality (LMI) and parametrized first-order model transformation,several novel conditions guaranteeing the delaydependent and the delay-independent exponential stabilities are obtained.A numerical example is given to illustrate the effectiveness of our results.

  2. Cellular neural network implementation using a phase-only joint transform correlator

    Science.gov (United States)

    Zhang, Shuqun; Karim, Mohammad A.

    1999-04-01

    A phase-only joint transform correlator (JTC) is used to realize cellular neural networks (CNNs). The operation of summing cross-correlations of bipolar data in CNNs can be realized in parallel by phase-encoding bipolar data. Compared to other optical systems for implementing CNNs, the proposed method offers the advantages of easier implementation and robustness in terms of system alignment, and requires neither electronic precalculation nor data rearrangement. Simulation results of the proposed optical CNNs for edge detection are provided.

  3. Global Exponential Stability of Almost Periodic Solution of Cellular Neural Networks with Time-Varying Delays

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In this paper, global exponential stability of almost periodic solution of cellular neural networks with time-varing delays (CNNVDs) is considered. By using the methods of the topological degree theory and generalized Halanay inequality, a few new applicable criteria are established for the existence and global exponential stability of almost periodic solution. Some previous results are improved and extended in this letter and one example is given to illustrate the effectiveness of the new results.

  4. A Proposal for Energy-Efficient Cellular Neural Network based on Spintronic Devices

    OpenAIRE

    2016-01-01

    Due to the massive parallel computing capability and outstanding image and signal processing performance, cellular neural network (CNN) is one promising type of non-Boolean computing system that can outperform the traditional digital logic computation and mitigate the physical scaling limit of the conventional CMOS technology. The CNN was originally implemented by VLSI analog technologies with operational amplifiers and operational transconductance amplifiers as neurons and synapses, respecti...

  5. Electric Energy Demand Forecast of Nanchang based on Cellular Genetic Algorithm and BP Neural Network

    OpenAIRE

    Cheng Yugui

    2013-01-01

    A kind of power forecast model combined cellular genetic algorithm with BP neural network was established in this article. Mid-long term power demand in urban areas was done load forecasting and analysis based on material object of the actual power consumption in urban areas of Nanchang. The results show that this method has the characteristic of the minimum training times, the shortest consumption time, the minimum error and the shortest operation time to obtain the best fitting effect.  

  6. An Asynchronous Recurrent Network of Cellular Automaton-Based Neurons and Its Reproduction of Spiking Neural Network Activities.

    Science.gov (United States)

    Matsubara, Takashi; Torikai, Hiroyuki

    2016-04-01

    Modeling and implementation approaches for the reproduction of input-output relationships in biological nervous tissues contribute to the development of engineering and clinical applications. However, because of high nonlinearity, the traditional modeling and implementation approaches encounter difficulties in terms of generalization ability (i.e., performance when reproducing an unknown data set) and computational resources (i.e., computation time and circuit elements). To overcome these difficulties, asynchronous cellular automaton-based neuron (ACAN) models, which are described as special kinds of cellular automata that can be implemented as small asynchronous sequential logic circuits have been proposed. This paper presents a novel type of such ACAN and a theoretical analysis of its excitability. This paper also presents a novel network of such neurons, which can mimic input-output relationships of biological and nonlinear ordinary differential equation model neural networks. Numerical analyses confirm that the presented network has a higher generalization ability than other major modeling and implementation approaches. In addition, Field-Programmable Gate Array-implementations confirm that the presented network requires lower computational resources.

  7. Measuring information flow in cellular networks by the systems biology method through microarray data.

    Science.gov (United States)

    Chen, Bor-Sen; Li, Cheng-Wei

    2015-01-01

    In general, it is very difficult to measure the information flow in a cellular network directly. In this study, based on an information flow model and microarray data, we measured the information flow in cellular networks indirectly by using a systems biology method. First, we used a recursive least square parameter estimation algorithm to identify the system parameters of coupling signal transduction pathways and the cellular gene regulatory network (GRN). Then, based on the identified parameters and systems theory, we estimated the signal transductivities of the coupling signal transduction pathways from the extracellular signals to each downstream protein and the information transductivities of the GRN between transcription factors in response to environmental events. According to the proposed method, the information flow, which is characterized by signal transductivity in coupling signaling pathways and information transductivity in the GRN, can be estimated by microarray temporal data or microarray sample data. It can also be estimated by other high-throughput data such as next-generation sequencing or proteomic data. Finally, the information flows of the signal transduction pathways and the GRN in leukemia cancer cells and non-leukemia normal cells were also measured to analyze the systematic dysfunction in this cancer from microarray sample data. The results show that the signal transductivities of signal transduction pathways change substantially from normal cells to leukemia cancer cells.

  8. Optimized Energy Procurement for Cellular Networks with Uncertain Renewable Energy Generation

    KAUST Repository

    Rached, Nadhir B.

    2017-02-07

    Renewable energy (RE) is an emerging solution for reducing carbon dioxide (CO2) emissions from cellular networks. One of the challenges of using RE sources is to handle its inherent uncertainty. In this paper, a RE powered cellular network is investigated. For a one-day operation cycle, the cellular network aims to reduce energy procurement costs from the smart grid by optimizing the amounts of energy procured from their locally deployed RE sources as well as from the smart grid. In addition to that, it aims to determine the extra amount of energy to be sold to the electrical grid at each time period. Chance constrained optimization is first proposed to deal with the randomness in the RE generation. Then, to make the optimization problem tractable, two well- know convex approximation methods, namely; Chernoff and Chebyshev based-approaches, are analyzed in details. Numerical results investigate the optimized energy procurement for various daily scenarios and compare between the performances of the employed convex approximation approaches.

  9. Impact of Channel Partitioning and Relay Placement on Resource Allocation in OFDMA Cellular Networks

    Directory of Open Access Journals (Sweden)

    Sultan F. Meko

    2012-07-01

    Full Text Available Tremendous growth in the demand for wireless applications such as streaming audio/videos, Skype and video games require high data rate irrespective of user’s location in the cellular network. However, the Quality of Service (QoS of users degrades at the cell boundary. Relay enhanced multi-hop cellular network is one of the cost effective solution to improve the performance of cell edge users. Optimal deployment of Fixed Relay Nodes (FRNs is essential to satisfy the QoS requirement of edge users. We propose new schemes for channel partitioning and FRN placement in cellular networks. Path-loss, Signal to Interference and Noise Ratio (SINR experienced by users, and effects of shadowing have been considered. The analysis gives more emphasis on the cell-edge users (worst case scenario. The results show that these schemes achieve higher system performance in terms of spectral efficiency and also increase the user data rate at the cell edge.

  10. LTE-A cellular networks multi-hop relay for coverage, capacity and performance enhancement

    CERN Document Server

    Yahya, Abid

    2017-01-01

    In this book, three different methods are presented to enhance the capacity and coverage area in LTE-A cellular networks. The scope involves the evaluation of the effect of the RN location in terms of capacity and the determination of the optimum location of the relay that provides maximum achievable data rate for users with limited interference at the cell boundaries. This book presents a new model to enhance both capacity and coverage area in LTE-A cellular network by determining the optimum location for the RN with limited interference. The new model is designed to enhance the capacity of the relay link by employing two antennas in RN. This design enables the relay link to absorb more users at cell edge regions. An algorithm called the Balance Power Algorithm (BPA) is developed to reduce MR power consumption. The book pertains to postgraduate students and researchers in wireless & mobile communications. Provides a variety of methods for enhancing capacity and coverage in LTE-A cellular networks Develop...

  11. Creative elements: network-based predictions of active centres in proteins, cellular and social networks

    CERN Document Server

    Csermely, Peter

    2008-01-01

    Active centres and hot spots of proteins have a paramount importance in enzyme action, protein complex formation and drug design. Recently a number of publications successfully applied the analysis of residue networks to predict active centres in proteins. Most real-world networks show a number of properties, such as small-worldness or scale-free degree distribution, which are rather general features of networks from molecules to the society. Based on extensive analogies I propose that the existing findings and methodology enable us to detect active centres in cells, social networks and ecosystems. Members of these active centres are creative elements of the respective networks, which may help them to survive unprecedented, novel challenges, and play a key role in the development, survival and evolvability of complex systems.

  12. Base Station Ordering for Emergency Call Localization in Ultra-dense Cellular Networks

    KAUST Repository

    Elsawy, Hesham

    2017-10-04

    This paper proposes the base station ordering localization technique (BoLT) for emergency call localization in cellular networks. Exploiting the foreseen ultra-densification of the next-generation (5G and beyond) cellular networks, we utilize higher-order Voronoi tessellations to provide ubiquitous localization services that are in compliance to the public safety standards in cellular networks. The proposed localization algorithm runs at the base stations (BSs) and requires minimal operation from agents (i.e., mobile users). Particularly, BoLT requires each agent to feedback a neighbor cell list (NCL) that contains the order of neighboring BSs based on the received signal power in the pilots sent from these BSs. Moreover, this paper utilizes stochastic geometry to develop a tractable mathematical model to assess the performance of BoLT in a general network setting. The goal of this paper is to answer the following two fundamental questions: i) how many BSs should be ordered and reported by the agent to achieve a desirable localization accuracy? and ii) what is the localization error probability given that the pilot signals are subject to shadowing? Assuming that the BSs are deployed according to a Poisson point process (PPP), we answer these two questions via characterizing the tradeoff between the area of location region (ALR) and the localization error probability in terms of the number of BSs ordered by the agent. The results show that reporting the order of six neighboring BSs is sufficient to localize the agent within 10% of the cell area. Increasing the number of reported BSs to ten confines the location region to 1% of the cell area. This would translate to the range of a few meters to decimeters in the foreseen ultra-dense 5G networks.

  13. A New Cellular Architecture for Information Retrieval from Sensor Networks through Embedded Service and Security Protocols

    Directory of Open Access Journals (Sweden)

    Aamir Shahzad

    2016-06-01

    Full Text Available Substantial changes have occurred in the Information Technology (IT sectors and with these changes, the demand for remote access to field sensor information has increased. This allows visualization, monitoring, and control through various electronic devices, such as laptops, tablets, i-Pads, PCs, and cellular phones. The smart phone is considered as a more reliable, faster and efficient device to access and monitor industrial systems and their corresponding information interfaces anywhere and anytime. This study describes the deployment of a protocol whereby industrial system information can be securely accessed by cellular phones via a Supervisory Control And Data Acquisition (SCADA server. To achieve the study goals, proprietary protocol interconnectivity with non-proprietary protocols and the usage of interconnectivity services are considered in detail. They support the visualization of the SCADA system information, and the related operations through smart phones. The intelligent sensors are configured and designated to process real information via cellular phones by employing information exchange services between the proprietary protocol and non-proprietary protocols. SCADA cellular access raises the issue of security flaws. For these challenges, a cryptography-based security method is considered and deployed, and it could be considered as a part of a proprietary protocol. Subsequently, transmission flows from the smart phones through a cellular network.

  14. A New Cellular Architecture for Information Retrieval from Sensor Networks through Embedded Service and Security Protocols.

    Science.gov (United States)

    Shahzad, Aamir; Landry, René; Lee, Malrey; Xiong, Naixue; Lee, Jongho; Lee, Changhoon

    2016-06-14

    Substantial changes have occurred in the Information Technology (IT) sectors and with these changes, the demand for remote access to field sensor information has increased. This allows visualization, monitoring, and control through various electronic devices, such as laptops, tablets, i-Pads, PCs, and cellular phones. The smart phone is considered as a more reliable, faster and efficient device to access and monitor industrial systems and their corresponding information interfaces anywhere and anytime. This study describes the deployment of a protocol whereby industrial system information can be securely accessed by cellular phones via a Supervisory Control And Data Acquisition (SCADA) server. To achieve the study goals, proprietary protocol interconnectivity with non-proprietary protocols and the usage of interconnectivity services are considered in detail. They support the visualization of the SCADA system information, and the related operations through smart phones. The intelligent sensors are configured and designated to process real information via cellular phones by employing information exchange services between the proprietary protocol and non-proprietary protocols. SCADA cellular access raises the issue of security flaws. For these challenges, a cryptography-based security method is considered and deployed, and it could be considered as a part of a proprietary protocol. Subsequently, transmission flows from the smart phones through a cellular network.

  15. A New Cellular Architecture for Information Retrieval from Sensor Networks through Embedded Service and Security Protocols

    Science.gov (United States)

    Shahzad, Aamir; Landry, René; Lee, Malrey; Xiong, Naixue; Lee, Jongho; Lee, Changhoon

    2016-01-01

    Substantial changes have occurred in the Information Technology (IT) sectors and with these changes, the demand for remote access to field sensor information has increased. This allows visualization, monitoring, and control through various electronic devices, such as laptops, tablets, i-Pads, PCs, and cellular phones. The smart phone is considered as a more reliable, faster and efficient device to access and monitor industrial systems and their corresponding information interfaces anywhere and anytime. This study describes the deployment of a protocol whereby industrial system information can be securely accessed by cellular phones via a Supervisory Control And Data Acquisition (SCADA) server. To achieve the study goals, proprietary protocol interconnectivity with non-proprietary protocols and the usage of interconnectivity services are considered in detail. They support the visualization of the SCADA system information, and the related operations through smart phones. The intelligent sensors are configured and designated to process real information via cellular phones by employing information exchange services between the proprietary protocol and non-proprietary protocols. SCADA cellular access raises the issue of security flaws. For these challenges, a cryptography-based security method is considered and deployed, and it could be considered as a part of a proprietary protocol. Subsequently, transmission flows from the smart phones through a cellular network. PMID:27314351

  16. COMBINING FUZZY AND CELLULAR LEARNING AUTOMATA METHODS FOR CLUSTERING WIRELESS SENSOR NETWORK TO INCREASE LIFE OF THE NETWORK

    Directory of Open Access Journals (Sweden)

    Javad Aramideh

    2014-11-01

    Full Text Available Wireless sensor networks have attracted attention of researchers considering their abundant applications. One of the important issues in this network is limitation of energy consumption which is directly related to life of the network. One of the main works which have been done recently to confront with this problem is clustering. In this paper, an attempt has been made to present clustering method which performs clustering in two stages. In the first stage, it specifies candidate nodes for being head cluster with fuzzy method and in the next stage, the node of the head cluster is determined among the candidate nodes with cellular learning automata. Advantage of the clustering method is that clustering has been done based on three main parameters of the number of neighbors, energy level of nodes and distance between each node and sink node which results in selection of the best nodes as a candidate head of cluster nodes. Connectivity of network is also evaluated in the second part of head cluster determination. Therefore, more energy will be stored by determining suitable head clusters and creating balanced clusters in the network and consequently, life of the network increases.

  17. Modeling Cellular Networks with Full Duplex D2D Communication: A Stochastic Geometry Approach

    KAUST Repository

    Ali, Konpal S.

    2016-08-24

    Full-duplex (FD) communication is optimistically promoted to double the spectral efficiency if sufficient self-interference cancellation (SIC) is achieved. However, this is not true when deploying FD-communication in a large-scale setup due to the induced mutual interference. Therefore, a large-scale study is necessary to draw legitimate conclusions about gains associated with FD-communication. This paper studies the FD operation for underlay device-to-device (D2D) communication sharing the uplink resources in cellular networks. We propose a disjoint fine-tuned selection criterion for the D2D and FD modes of operation. Then, we develop a tractable analytical paradigm, based on stochastic geometry, to calculate the outage probability and rate for cellular and D2D users. The results reveal that even in the case of perfect SIC, due to the increased interference injected to the network by FD-D2D communication, having all proximity UEs transmit in FD-D2D is not beneficial for the network. However, if the system parameters are carefully tuned, non-trivial network spectral-efficiency gains (64% shown) can be harvested. We also investigate the effects of imperfect SIC and D2D-link distance distribution on the harvested FD gains.

  18. Hybrid RF and Digital Beamformer for Cellular Networks: Algorithms, Microwave Architectures, and Measurements

    Science.gov (United States)

    Venkateswaran, Vijay; Pivit, Florian; Guan, Lei

    2016-07-01

    Modern wireless communication networks, particularly cellular networks utilize multiple antennas to improve the capacity and signal coverage. In these systems, typically an active transceiver is connected to each antenna. However, this one-to-one mapping between transceivers and antennas will dramatically increase the cost and complexity of a large phased antenna array system. In this paper, firstly we propose a \\emph{partially adaptive} beamformer architecture where a reduced number of transceivers with a digital beamformer (DBF) is connected to an increased number of antennas through an RF beamforming network (RFBN). Then, based on the proposed architecture, we present a methodology to derive the minimum number of transceivers that are required for marco-cell and small-cell base stations, respectively. Subsequently, in order to achieve optimal beampatterns with given cellular standard requirements and RF operational constraints, we propose efficient algorithms to jointly design DBF and RFBN. Starting from the proposed algorithms, we specify generic microwave RFBNs for optimal marco-cell and small-cell networks. In order to verify the proposed approaches, we compare the performance of RFBN using simulations and anechoic chamber measurements. Experimental measurement results confirm the robustness and performance of the proposed hybrid DBF-RFBN concept eventually ensuring that theoretical multi-antenna capacity and coverage are achieved at a little incremental cost.

  19. In-Band α-Duplex Scheme for Cellular Networks: A Stochastic Geometry Approach

    KAUST Repository

    Alammouri, Ahmad

    2016-07-13

    In-band full-duplex (FD) communications have been optimistically promoted to improve the spectrum utilization and efficiency. However, the penetration of FD communications to the cellular networks domain is challenging due to the imposed uplink/downlink interference. This paper presents a tractable framework, based on stochastic geometry, to study FD communications in cellular networks. Particularly, we assess the FD communications effect on the network performance and quantify the associated gains. The study proves the vulnerability of the uplink to the downlink interference and shows that FD rate gains harvested in the downlink (up to 97%) come at the expense of a significant degradation in the uplink rate (up to 94%). Therefore, we propose a novel fine-grained duplexing scheme, denoted as -duplex scheme, which allows a partial overlap between the uplink and the downlink frequency bands. We derive the required conditions to harvest rate gains from the -duplex scheme and show its superiority to both the FD and half-duplex (HD) schemes. In particular, we show that the -duplex scheme provides a simultaneous improvement of 28% for the downlink rate and 56% for the uplink rate. Finally, we show that the amount of the overlap can be optimized based on the network design objective.

  20. Motion Adaptive Vertical Handoff in Cellular/WLAN Heterogeneous Wireless Network

    Directory of Open Access Journals (Sweden)

    Limin Li

    2014-01-01

    Full Text Available In heterogeneous wireless network, vertical handoff plays an important role for guaranteeing quality of service and overall performance of network. Conventional vertical handoff trigger schemes are mostly developed from horizontal handoff in homogeneous cellular network. Basically, they can be summarized as hysteresis-based and dwelling-timer-based algorithms, which are reliable on avoiding unnecessary handoff caused by the terminals dwelling at the edge of WLAN coverage. However, the coverage of WLAN is much smaller compared with cellular network, while the motion types of terminals can be various in a typical outdoor scenario. As a result, traditional algorithms are less effective in avoiding unnecessary handoff triggered by vehicle-borne terminals with various speeds. Besides that, hysteresis and dwelling-timer thresholds usually need to be modified to satisfy different channel environments. For solving this problem, a vertical handoff algorithm based on Q-learning is proposed in this paper. Q-learning can provide the decider with self-adaptive ability for handling the terminals’ handoff requests with different motion types and channel conditions. Meanwhile, Neural Fuzzy Inference System (NFIS is embedded to retain a continuous perception of the state space. Simulation results verify that the proposed algorithm can achieve lower unnecessary handoff probability compared with the other two conventional algorithms.

  1. Universal Intelligent Small Cell (UnISCell for next generation cellular networks

    Directory of Open Access Journals (Sweden)

    Mohammad Patwary

    2016-11-01

    Full Text Available Exploring innovative cellular architectures to achieve enhanced system capacity and good coverage has become a critical issue towards realizing the next generation of wireless communications. In this context, this paper proposes a novel concept of Universal Intelligent Small Cell (UnISCell for enabling the densification of the next generation of cellular networks. The proposed novel concept envisions an integrated platform of providing a strong linkage between different stakeholders such as street lighting networks, landline telephone networks and future wireless networks, and is universal in nature being independent of the operating frequency bands and traffic types. The main motivating factors for the proposed small cell concept are the need of public infrastructure re-engineering, and the recent advances in several enabling technologies. First, we highlight the main concepts of the proposed UnISCell platform. Subsequently, we present two deployment scenarios for the proposed UnISCell concept considering infrastructure sharing and service sharing as important aspects. We then describe the key future technologies for enabling the proposed UnISCell concept and present a use case example with the help of numerical results. Finally, we conclude this article by providing some interesting future recommendations.

  2. A Stochastic-Geometry Approach to Coverage in Cellular Networks with Multi-Cell Cooperation

    CERN Document Server

    Huang, Kaibin

    2011-01-01

    Multi-cell cooperation is a promising approach for mitigating inter-cell interference in dense cellular networks. Quantifying the performance of multi-cell cooperation is challenging as it integrates physical-layer techniques and network topologies. For tractability, existing work typically relies on the over-simplified Wyner-type models. In this paper, we propose a new stochastic-geometry model for a cellular network with multi-cell cooperation, which accounts for practical factors including the irregular locations of base stations (BSs) and the resultant path-losses. In particular, the proposed network-topology model has three key features: i) the cells are modeled using a Poisson random tessellation generated by Poisson distributed BSs, ii) multi-antenna BSs are clustered using a hexagonal lattice and BSs in the same cluster mitigate mutual interference by spatial interference avoidance, iii) BSs near cluster edges access a different sub-channel from that by other BSs, shielding cluster-edge mobiles from s...

  3. Computation of steady-state probability distributions in stochastic models of cellular networks.

    Directory of Open Access Journals (Sweden)

    Mark Hallen

    2011-10-01

    Full Text Available Cellular processes are "noisy". In each cell, concentrations of molecules are subject to random fluctuations due to the small numbers of these molecules and to environmental perturbations. While noise varies with time, it is often measured at steady state, for example by flow cytometry. When interrogating aspects of a cellular network by such steady-state measurements of network components, a key need is to develop efficient methods to simulate and compute these distributions. We describe innovations in stochastic modeling coupled with approaches to this computational challenge: first, an approach to modeling intrinsic noise via solution of the chemical master equation, and second, a convolution technique to account for contributions of extrinsic noise. We show how these techniques can be combined in a streamlined procedure for evaluation of different sources of variability in a biochemical network. Evaluation and illustrations are given in analysis of two well-characterized synthetic gene circuits, as well as a signaling network underlying the mammalian cell cycle entry.

  4. Cognitive radio networks efficient resource allocation in cooperative sensing, cellular communications, high-speed vehicles, and smart grid

    CERN Document Server

    Jiang, Tao; Cao, Yang

    2015-01-01

    PrefaceAcknowledgmentsAbout the AuthorsIntroductionCognitive Radio-Based NetworksOpportunistic Spectrum Access NetworksCognitive Radio Networks with Cooperative SensingCognitive Radio Networks for Cellular CommunicationsCognitive Radio Networks for High-Speed VehiclesCognitive Radio Networks for a Smart GridContent and OrganizationTransmission Slot Allocation in an Opportunistic Spectrum Access NetworkSingle-User Single-Channel System ModelProbabilistic Slot Allocation SchemeOptimal Probabilistic Slot AllocationBaseline PerformanceExponential DistributionHyper-Erlang DistributionPerformance An

  5. Impact of joint resource partitioning and routing on performance of relay enhanced cellular networks

    Institute of Scientific and Technical Information of China (English)

    LIU Tao; RONG Meng-tian; SHI Hong-kui

    2008-01-01

    Radio resource assignment schemes and routing strategies in relay enhanced cellular networks are proposed in this paper. Under the reuse partitioning-based frequency planning framework, the intra-cell re-source partitioning between the base station and relay nodes was addressed firstly by introducing a metric of ef-fective reuse factor. Then, coverage-oriented and capacity-oriented routings, as well as two link bandwidth as-signment schemes" equal-bandwidth per link" and " equal-bandwidth per mobile station" were developed.These key issues and their impacts on the system performance were analyzed comprehensively and supported by simulations. Results show that the cell capacity and edge user throughput of the proposed network are superior to the traditional non-relay network when an appropriate effective reuse factor is adopted.

  6. Cognitive Radio and its Application for Next Generation Cellular and Wireless Networks

    CERN Document Server

    Muntean, Gabriel-Miro

    2012-01-01

    This book provides a broad introduction to Cognitive Radio, which attempts to mimic human cognition and reasoning applied to Software Defined Radio and reconfigurable radio over wireless networks.  It provides readers with significant technical and practical insights into different aspects of Cognitive Radio, starting from a basic background, the principle behind the technology, the inter-related technologies and application to cellular and vehicular networks, the technical challenges, implementation and future trends.  The discussion balances theoretical concepts and practical implementation. Wherever feasible, the different concepts explained are linked to application of the corresponding scheme in a particular wireless standard.     This book has two sections: the first section begins with an introduction to cognitive radio and discusses in detail various, inter-dependent technologies such as network coding, software-based radio, dirty RF, etc. and their relation to cognitive radio. The second section ...

  7. Network-Guided Key Gene Discovery for a Given Cellular Process

    DEFF Research Database (Denmark)

    He, Feng Q; Ollert, Markus

    2017-01-01

    Identification of key genes for a given physiological or pathological process is an essential but still very challenging task for the entire biomedical research community. Statistics-based approaches, such as genome-wide association study (GWAS)- or quantitative trait locus (QTL)-related analysis...... have already made enormous contributions to identifying key genes associated with a given disease or phenotype, the success of which is however very much dependent on a huge number of samples. Recent advances in network biology, especially network inference directly from genome-scale data...... and the following-up network analysis, opens up new avenues to predict key genes driving a given biological process or cellular function. Here we review and compare the current approaches in predicting key genes, which have no chances to stand out by classic differential expression analysis, from gene...

  8. Increasing the coverage area through relay node deployment in long term evolution advanced cellular networks

    Science.gov (United States)

    Aldhaibani, Jaafar A.; Ahmad, R. B.; Yahya, A.; Azeez, Suzan A.

    2015-05-01

    Wireless multi-hop relay networks have become very important technologies in mobile communications. These networks ensure high throughput and coverage extension with a low cost. The poor capacity at cell edges is not enough to meet with growing demand of high capacity and throughput irrespective of user's placement in the cellular network. In this paper we propose optimal placement of relay node that provides maximum achievable rate at users and enhances the throughput and coverage at cell edge region. The proposed scheme is based on the outage probability at users and taken on account the interference between nodes. Numerical analyses along with simulation results indicated there are an improvement in capacity for users at the cell edge is 40% increment from all cell capacity.

  9. Error performance analysis in K-tier uplink cellular networks using a stochastic geometric approach

    KAUST Repository

    Afify, Laila H.

    2015-09-14

    In this work, we develop an analytical paradigm to analyze the average symbol error probability (ASEP) performance of uplink traffic in a multi-tier cellular network. The analysis is based on the recently developed Equivalent-in-Distribution approach that utilizes stochastic geometric tools to account for the network geometry in the performance characterization. Different from the other stochastic geometry models adopted in the literature, the developed analysis accounts for important communication system parameters and goes beyond signal-to-interference-plus-noise ratio characterization. That is, the presented model accounts for the modulation scheme, constellation type, and signal recovery techniques to model the ASEP. To this end, we derive single integral expressions for the ASEP for different modulation schemes due to aggregate network interference. Finally, all theoretical findings of the paper are verified via Monte Carlo simulations.

  10. Green collaboration in cognitive radio cellular networks with roaming and spectrum trading

    KAUST Repository

    Sboui, Lokman

    2015-08-30

    In this paper, we propose a new cognitive cellular network architecture based on the coexistence of primary and secondary networks, (PN) and (SN), respectively. The PN aims to minimize its energy consumption by switching off the maximum number of its BSs and offloading its users to the SN\\'s infrastructure to maintain its QoS. In return, the PN pays a roaming price and permits the SN to share or lease the spectrum at a certain price. We propose a low-complexity algorithm allowing the PN to minimize its energy consumption by selecting a suboptimal combination of active base stations. Our algorithm also optimizes the resource allocation of the SN to maximize its total sum-rate while respecting the minimal profit constraints for both networks. In the numerical results, we show that our proposed algorithm achieves close performances to the optimal exhaustive search algorithm. In addition, we investigate the impact of various system parameters in the collaboration decision.

  11. Cellular pulse-coupled neural network with adaptive weights for image segmentation and its VLSI implementation

    Science.gov (United States)

    Schreiter, Juerg; Ramacher, Ulrich; Heittmann, Arne; Matolin, Daniel; Schuffny, Rene

    2004-05-01

    We present a cellular pulse coupled neural network with adaptive weights and its analog VLSI implementation. The neural network operates on a scalar image feature, such as grey scale or the output of a spatial filter. It detects segments and marks them with synchronous pulses of the corresponding neurons. The network consists of integrate-and-fire neurons, which are coupled to their nearest neighbors via adaptive synaptic weights. Adaptation follows either one of two empirical rules. Both rules lead to spike grouping in wave like patterns. This synchronous activity binds groups of neurons and labels the corresponding image segments. Applications of the network also include feature preserving noise removal, image smoothing, and detection of bright and dark spots. The adaptation rules are insensitive for parameter deviations, mismatch and non-ideal approximation of the implied functions. That makes an analog VLSI implementation feasible. Simulations showed no significant differences in the synchronization properties between networks using the ideal adaptation rules and networks resembling implementation properties such as randomly distributed parameters and roughly implemented adaptation functions. A prototype is currently being designed and fabricated using an Infineon 130nm technology. It comprises a 128 × 128 neuron array, analog image memory, and an address event representation pulse output.

  12. Evaluating the Performance of Fast Handover for Hierarchical MIPv6 in Cellular Networks

    Directory of Open Access Journals (Sweden)

    Li Jun Zhang

    2008-06-01

    Full Text Available Next-Generation Wireless Networks (NGWNs present an all-IP-based architecture integrating existing cellular networks with Wireless Local Area Networks (WLANs, Wireless Metropolitan Area Networks (WMANs, ad hoc networks, Bluetooth, etc. This makes mobility management an important issue for users roaming among these networks/systems. On one hand, intelligent schemes need to be devised to empower mobile users to benefit from the IP-based technology. On the other hand, new solutions are required to take into account global roaming among various radio access technologies and support of real-time multimedia services. This paper presents a comprehensive performance analysis of Fast handover for Hierarchical Mobile IPv6 (F-HMIPv6 using the fluid-flow and randomwalk mobility models. Location update cost, packet delivery cost and total cost functions are formulated based on the proposed analytical models. We investigate the impact of several wireless system factors such as user velocity, user density, mobility domain size, session-to-mobility ratio on these costs, and present some numerical results.

  13. Power Control for D2D Underlay Cellular Networks With Channel Uncertainty

    KAUST Repository

    Memmi, Amen

    2016-12-26

    Device-to-device (D2D) communications underlying the cellular infrastructure are a technology that have been proposed recently as a promising solution to enhance cellular network capabilities. It improves spectrum utilization, overall throughput, and energy efficiency while enabling new peer-to-peer and location-based applications and services. However, interference is the major challenge, since the same resources are shared by both systems. Therefore, interference management techniques are required to keep the interference under control. In this paper, in order to mitigate interference, we consider centralized and distributed power control algorithms in a one-cell random network model. Existing results on D2D underlay networks assume perfect channel state information (CSI). This assumption is usually unrealistic in practice due to the dynamic nature of wireless channels. Thus, it is of great interest to study and evaluate achievable performances under channel uncertainty. Differently from previous works, we are assuming that the CSI may be imperfect and include estimation errors. In the centralized approach, we derive the optimal powers that maximize the coverage probability and the rate of the cellular user while scheduling as many D2D links as possible. These powers are computed at the base station (BS) and then delivered to the users, and hence the name “centralized”. For the distributed method, the ON–OFF power control and the truncated channel inversion are proposed. Expressions of coverage probabilities are established in the function of D2D links intensity, pathloss exponent, and estimation error variance. Results show the important influence of CSI error on achievable performances and thus how crucial it is to consider it while designing networks and evaluating performances.

  14. Perturbation in mitochondrial network dynamics and in complex I dependent cellular respiration in schizophrenia.

    Science.gov (United States)

    Rosenfeld, Marina; Brenner-Lavie, Hanit; Ari, Shunit Gal-Ben; Kavushansky, Alexandra; Ben-Shachar, Dorit

    2011-05-15

    Mitochondria have been suggested to be involved in the pathology of bipolar disorder (BD) and schizophrenia. However, the mechanism underlying mitochondrial dysfunction is unclear. Mitochondrial network dynamics, which reflects cellular metabolic state, is important for embryonic development, synapse formation, and neurodegeneration. This study aimed to investigate mitochondrial network dynamics and its plausible association with abnormal cellular oxygen consumption in schizophrenia. Viable Epstein-Barr virus (EBV)-transformed lymphocytes (lymphoblastoids) from DSM-IV diagnosed patients with schizophrenia (n = 17), BD (n = 15), and healthy control subjects (n = 15) were assessed for mitochondrial respiration, mitochondrial dynamics, and relevant protein levels by oxygraph, confocal microscopy, and immunoblotting, respectively. Respiration of schizophrenia-derived lymphoblastoids was significantly lower compared with control subjects, and was twice as sensitive to dopamine (DA)-induced inhibition. Unlike DA, haloperidol inhibited complex I-driven respiration to a similar extent in both schizophrenia and the control cells. Both drugs interact with complex I but at different sites. At the site of DA interaction, we found alterations in protein levels of three subunits of complex I in schizophrenia. In addition, we observed structural and connectivity perturbations in the mitochondrial network, associated with alterations in the profusion protein OPA1, which was similarly reduced in schizophrenia prefrontal cortex specimens. None of these alterations were observed in the BD cells, which were similar to control cells. We show impaired mitochondrial network dynamics associated with reduced cellular respiration and complex I abnormalities in schizophrenia but not in BD. If these findings represent disease-specific alterations, they may become an endophenotype biomarker for schizophrenia. Copyright © 2011 Society of Biological Psychiatry. Published by Elsevier Inc. All

  15. Dynamic circadian protein-protein interaction networks predict temporal organization of cellular functions.

    Directory of Open Access Journals (Sweden)

    Thomas Wallach

    2013-03-01

    Full Text Available Essentially all biological processes depend on protein-protein interactions (PPIs. Timing of such interactions is crucial for regulatory function. Although circadian (~24-hour clocks constitute fundamental cellular timing mechanisms regulating important physiological processes, PPI dynamics on this timescale are largely unknown. Here, we identified 109 novel PPIs among circadian clock proteins via a yeast-two-hybrid approach. Among them, the interaction of protein phosphatase 1 and CLOCK/BMAL1 was found to result in BMAL1 destabilization. We constructed a dynamic circadian PPI network predicting the PPI timing using circadian expression data. Systematic circadian phenotyping (RNAi and overexpression suggests a crucial role for components involved in dynamic interactions. Systems analysis of a global dynamic network in liver revealed that interacting proteins are expressed at similar times likely to restrict regulatory interactions to specific phases. Moreover, we predict that circadian PPIs dynamically connect many important cellular processes (signal transduction, cell cycle, etc. contributing to temporal organization of cellular physiology in an unprecedented manner.

  16. Performance Analysis of User Pairing Algorithm in Full-Duplex Cellular Networks

    Directory of Open Access Journals (Sweden)

    Wonjong Noh

    2017-01-01

    Full Text Available In a full duplexing (FD wireless cellular network, a base station operates in FD mode, while the downlink (DL and uplink (UL users operate in half duplexing (HD mode. Thus, the downlink and uplink transmissions occur simultaneously so that interuser interference from a UL to a DL user occurs. In an FD network, the main challenge to minimize the interuser interference is user pairing, which determines a pair of DL and UL users who use the same radio resource simultaneously. We formulate a nonconvex optimization problem for user pairing to maximize the cell throughput. Then, we propose a heuristic user pairing algorithm with low complexity. This algorithm is designed such that the DL user having a better signal quality has higher priority to choose its paired UL user for throughput maximization. Thereafter, we conduct theoretical performance analysis of the FD cellular system based on stochastic geometry and analyze the impact of the user paring algorithm on the performance of the FD cellular system. Results show that the FD system that uses the proposed user pairing algorithm effectively reduces the interuser interference and approaches optimal performance. It also considerably outperforms the FD system using a random user pairing and almost doubles the conventional HD system in terms of cell throughput.

  17. Towards operational rainfall monitoring with microwave links from cellular telecommunication networks

    Science.gov (United States)

    Overeem, Aart; Leijnse, Hidde; Uijlenhoet, Remko

    2017-04-01

    The basic principle of rainfall estimation using microwave links is as follows. Rainfall attenuates the electromagnetic signals transmitted from one telephone tower to another. By measuring the received power at one end of a microwave link as a function of time, the path-integrated attenuation due to rainfall can be calculated, which can be converted to average rainfall intensities over the length of a link. Microwave links from cellular communication networks have been proposed as a promising new rainfall measurement technique since one decade. They are particularly interesting for those countries where few surface rainfall observations are available. Yet too date no operational (real-time) link-based rainfall products are available. To advance the process towards operational application and upscaling of this technique, long time series should be analyzed for different networks and climates. Here the potential for long-term large-scale operational rainfall monitoring is demonstrated by utilizing a 2.5-year data set from a cellular communication network. The data set consists of roughly 2,000 links covering the land surface of the Netherlands (35,500 square kilometers). The quality of link rainfall maps is thoroughly quantified by an extensive validation against independent gauge-adjusted radar rainfall maps for, among others, different seasons and extremes. One of the goals is to quantify whether the cellular telecommunication network can yield rainfall maps of comparable quality as those based on automatic rain gauge data (with a density of 1 gauge per 1000 square kilometers). Developing countries will usually have rain gauge networks with a lower density (and little or no weather radars). This helps to assess the possibly added value of link-based rainfall estimates with respect to those from existing rain gauge networks. Moreover, this shows the possibly added value of link rainfall estimates for adjustment of radar rainfall images. The results further confirm

  18. Exploiting the Multi-Service Domain Protecting Interface

    Science.gov (United States)

    2012-10-17

    the concern for data protection is limited to national interests only, that is, protection of national secrets and human lives. 3 This is not to say...responsible for communicating with a Juniper router through its management Ethernet interface. Panel 1 (reading left to right ) contains the series...2008. Kashyap , V., and H.K.J. Chu, “IP encapsulation and address resolution over InfiniBand networks,” 13 pp. The Internet Society, February 6

  19. Modeling and Analysis of K-Tier Downlink Heterogeneous Cellular Networks

    CERN Document Server

    Dhillon, Harpreet S; Baccelli, Francois; Andrews, Jeffrey G

    2011-01-01

    Cellular networks are in a major transition from a carefully planned set of large tower-mounted base-stations (BSs) to an irregular deployment of heterogeneous infrastructure elements that often additionally includes micro, pico, and femtocells, as well as distributed antennas. In this paper, we develop a tractable, flexible, and accurate model for a downlink heterogeneous cellular network (HCN) consisting of K tiers of randomly located BSs, where each tier may differ in terms of average transmit power, supported data rate and BS density. Assuming a mobile user connects to the strongest candidate BS, the resulting Signal-to-Interference-plus-Noise-Ratio (SINR) is greater than 1 when in coverage, Rayleigh fading, we derive an expression for the probability of coverage (equivalently outage) over the entire network under both open and closed access, which assumes a strikingly simple closed-form in the high SINR regime and is accurate down to -4 dB even under weaker assumptions. For external validation, we compar...

  20. Unified tractable model for downlink MIMO cellular networks using stochastic geometry

    KAUST Repository

    Afify, Laila H.

    2016-07-26

    Several research efforts are invested to develop stochastic geometry models for cellular networks with multiple antenna transmission and reception (MIMO). On one hand, there are models that target abstract outage probability and ergodic rate for simplicity. On the other hand, there are models that sacrifice simplicity to target more tangible performance metrics such as the error probability. Both types of models are completely disjoint in terms of the analytic steps to obtain the performance measures, which makes it challenging to conduct studies that account for different performance metrics. This paper unifies both techniques and proposes a unified stochastic-geometry based mathematical paradigm to account for error probability, outage probability, and ergodic rates in MIMO cellular networks. The proposed model is also unified in terms of the antenna configurations and leads to simpler error probability analysis compared to existing state-of-the-art models. The core part of the analysis is based on abstracting unnecessary information conveyed within the interfering signals by assuming Gaussian signaling. To this end, the accuracy of the proposed framework is verified against state-of-the-art models as well as system level simulations. We provide via this unified study insights on network design by reflecting system parameters effect on different performance metrics. © 2016 IEEE.

  1. Optimized Hybrid Resource Allocation in Wireless Cellular Networks with and without Channel Reassignment

    Directory of Open Access Journals (Sweden)

    Xin Wu

    2010-01-01

    Full Text Available In cellular networks, it is important to determine an optimal channel assignment scheme so that the available channels, which are considered as “limited” resources in cellular networks, are used as efficiently as possible. The objective of the channel assignment scheme is to minimize the call-blocking and the call-dropping probabilities. In this paper, we present two efficient integer linear programming (ILP formulations, for optimally allocating a channel (from a pool of available channels to an incoming call such that both “hard” and “soft” constraints are satisfied. Our first formulation, ILP1, does not allow channel reassignment of the existing calls, while our second formulation, ILP2, allows such reassignment. Both formulations can handle hard constraints, which includes co-site and adjacent channel constraints, in addition to the standard co-channel constraints. The simplified problem (with only co-channel constraints can be treated as a special case of our formulation. In addition to the hard constraints, we also consider soft constraints, such as, the packing condition, resonance condition, and limiting rearrangements, to further improve the network performance. We present the simulation results on a benchmark 49 cell environment with 70 channels that validate the performance of our approach.

  2. Device-Relaying in Cellular D2D Networks: A Fairness Perspective

    KAUST Repository

    Chaaban, Anas

    2015-10-24

    Device-to-Device (D2D) communication is envisioned to play a key role in 5G networks as a technique for meeting the demand for high data rates. In a cellular network, D2D allows not only direct communication between users, but also device relaying. In this paper, a simple instance of device-relaying is investigated, and its impact on fairness among users is studied. Namely, a cellular network consisting of two D2D-enabled users and a base-station (BS) is considered. Thus, the users who want to establish communication with the BS can act as relays for each other’s signals. While this problem is traditionally considered in the literature as a multiple-access channel with cooperation in the uplink, and a broadcast channel with cooperation in the downlink, we propose a different treatment of the problem as a multi-way channel. A simple communication scheme is proposed, and is shown to achieve significant gain in terms of fairness (measured by the symmetric rate supported) in comparison to the aforementioned traditional treatment.

  3. Cellular Signaling Networks Function as Generalized Wiener-Kolmogorov Filters to Suppress Noise

    Science.gov (United States)

    Hinczewski, Michael; Thirumalai, D.

    2014-10-01

    Cellular signaling involves the transmission of environmental information through cascades of stochastic biochemical reactions, inevitably introducing noise that compromises signal fidelity. Each stage of the cascade often takes the form of a kinase-phosphatase push-pull network, a basic unit of signaling pathways whose malfunction is linked with a host of cancers. We show that this ubiquitous enzymatic network motif effectively behaves as a Wiener-Kolmogorov optimal noise filter. Using concepts from umbral calculus, we generalize the linear Wiener-Kolmogorov theory, originally introduced in the context of communication and control engineering, to take nonlinear signal transduction and discrete molecule populations into account. This allows us to derive rigorous constraints for efficient noise reduction in this biochemical system. Our mathematical formalism yields bounds on filter performance in cases important to cellular function—such as ultrasensitive response to stimuli. We highlight features of the system relevant for optimizing filter efficiency, encoded in a single, measurable, dimensionless parameter. Our theory, which describes noise control in a large class of signal transduction networks, is also useful both for the design of synthetic biochemical signaling pathways and the manipulation of pathways through experimental probes such as oscillatory input.

  4. Cellular Signaling Networks Function as Generalized Wiener-Kolmogorov Filters to Suppress Noise

    Directory of Open Access Journals (Sweden)

    Michael Hinczewski

    2014-10-01

    Full Text Available Cellular signaling involves the transmission of environmental information through cascades of stochastic biochemical reactions, inevitably introducing noise that compromises signal fidelity. Each stage of the cascade often takes the form of a kinase-phosphatase push-pull network, a basic unit of signaling pathways whose malfunction is linked with a host of cancers. We show that this ubiquitous enzymatic network motif effectively behaves as a Wiener-Kolmogorov optimal noise filter. Using concepts from umbral calculus, we generalize the linear Wiener-Kolmogorov theory, originally introduced in the context of communication and control engineering, to take nonlinear signal transduction and discrete molecule populations into account. This allows us to derive rigorous constraints for efficient noise reduction in this biochemical system. Our mathematical formalism yields bounds on filter performance in cases important to cellular function—such as ultrasensitive response to stimuli. We highlight features of the system relevant for optimizing filter efficiency, encoded in a single, measurable, dimensionless parameter. Our theory, which describes noise control in a large class of signal transduction networks, is also useful both for the design of synthetic biochemical signaling pathways and the manipulation of pathways through experimental probes such as oscillatory input.

  5. Cellular network formation of hydrophobic alkanethiol capped gold nanoparticles on mica surface mediated by water islands

    Science.gov (United States)

    John, Neena S.; Raina, Gargi; Sharma, Ashutosh; Kulkarni, Giridhar U.

    2010-09-01

    Dendritic and cellular networks of nanoparticles are known to form commonly either by random diffusion-limited aggregation or by solvent evaporation dynamics. Using alkanethiol capped gold nanoparticles deposited on mica imaged under ambient and controlled water vapor conditions by atomic force microscope and in situ scanning electron microscope, respectively, we show a third mechanism in action. The cellular network consisting of open and closed polygons is formed by the nucleation and lateral growth of adsorbed water islands, the contact lines of which push the randomly distributed hydrophobic nanoparticles along the growth directions, eventually leading to the polygonal structure formation as the boundaries of the growing islands meet. Such nanoparticle displacement has been possible due to the weakly adhering nature of the hydrophilic substrate, mica. These results demonstrate an important but hitherto neglected effect of adsorbed water in the structure formation on hydrophilic substrates and provide a facile tool for the fabrication of nanoparticle networks without specific particle or substrate modifications and without a tight control on particle deposition conditions during the solvent evaporation.

  6. A game theoretical approach for cooperative environmentally friendly cellular networks powered by the smart grid

    KAUST Repository

    Ghazzai, Hakim

    2014-11-01

    This paper investigates the collaboration between multiple mobile operators to optimize the energy efficiency of cellular networks, maximize their profits or achieve or tradeoff between both objectives. Mobile operators cooperate together by eliminating redundant base stations (BSs) using a low complexity algorithm that aims to maximize their objective functions subject to a quality of service constraint. The problem is modeled as a two-level Stackelberg game: a mobile operator level and a smart grid level. Indeed, in our framework, we assume that cellular networks are powered by multiple energy providers existing in the smart grid characterized by different pollutant levels in addition to renewable energy source deployed in BS sites. The objective is to find the best active BS combination and the optimal procurement decision needed to the network operation during collaboration by considering electricity real-time pricing. Our study includes the daily traffic variation in addition to the daily green energy availability. Our simulation results show a significant saving in terms of CO2 emissions compared to the non-collaboration case and that cooperative mobile operators exploiting renewables are more awarded than traditional operators. © 2014 IEEE.

  7. Three Years of Country-Wide Rainfall Maps from Cellular Communication Networks

    Science.gov (United States)

    Uijlenhoet, R.; Overeem, A.; Leijnse, H.; Rios Gaona, M. F.

    2014-12-01

    Accurate rainfall observations with high spatial and temporal resolutions are needed for hydrological applications, agriculture, meteorology, and climate monitoring. However, the majority of the land surface of the earth lacks accurate rainfall information and the number of rain gauges is even severely declining in Europe, South-America, and Africa. This calls for alternative sources of rainfall information. Various studies have shown that microwave links from operational cellular communication networks may be used for rainfall monitoring. Such networks cover 20% of the land surface of the earth and have a high density, especially in urban areas. The basic principle of rainfall estimation using microwave links is as follows. Rainfall attenuates the electromagnetic signals transmitted from one telephone tower to another. By measuring the received power at one end of a microwave link as a function of time, the path-integrated attenuation due to rainfall can be calculated, which can be converted to average rainfall intensities over the length of a link. This is particularly interesting for those countries where few surface rainfall observations are available. A data set from a commercial microwave link network over the Netherlands is analyzed. The data set runs from January 2011 - January 2014 and consists of roughly 2000 links covering the land surface of the Netherlands (35,500 square kilometers). From this 3-year data set country-wide rainfall maps are retrieved, which are compared to a gauge-adjusted radar data set. The ability of cellular communication networks to estimate rainfall is studied for different temporal and spatial scales, as well as for several air temperature classes. Case studies are presented to investigate the performance of the algorithm during snow and sleet and to show the influence of dew formation on the antennas on the received signal levels. To summarize, the results further confirm the potential of these networks for rainfall monitoring.

  8. Three Years of Country-Wide Rainfall Maps from Cellular Communication Networks

    Science.gov (United States)

    Overeem, Aart; Rios Gaona, Manuel Felipe; Leijnse, Hidde; Uijlenhoet, Remko

    2015-04-01

    Accurate rainfall observations with high spatial and temporal resolutions are needed for hydrological applications, agriculture, meteorology, and climate monitoring. However, the majority of the land surface of the earth lacks accurate rainfall information and the number of rain gauges is even severely declining in Europe, South-America, and Africa. This calls for alternative sources of rainfall information. Various studies have shown that microwave links from operational cellular communication networks may be used for rainfall monitoring. Such networks cover 20% of the land surface of the earth and have a high density, especially in urban areas. The basic principle of rainfall estimation using microwave links is as follows. Rainfall attenuates the electromagnetic signals transmitted from one telephone tower to another. By measuring the received power at one end of a microwave link as a function of time, the path-integrated attenuation due to rainfall can be calculated, which can be converted to average rainfall intensities over the length of a link. This is particularly interesting for those countries where few surface rainfall observations are available. A data set from a commercial microwave link network over the Netherlands is analyzed. The data set runs from January 2011 - January 2014 and consists of roughly 2,000 links covering the land surface of the Netherlands (35,500 square kilometers). From this 3-year data set country-wide rainfall maps are retrieved, which are compared to a gauge-adjusted radar data set. The ability of cellular communication networks to estimate rainfall is studied for different temporal and spatial scales (including the catchment scale). To summarize, the results further confirm the potential of these networks for rainfall monitoring for hydrological applications.

  9. Segmentation algorithm via Cellular Neural/Nonlinear Network: implementation on Bio-inspired hardware platform

    Science.gov (United States)

    Karabiber, Fethullah; Vecchio, Pietro; Grassi, Giuseppe

    2011-12-01

    The Bio-inspired (Bi-i) Cellular Vision System is a computing platform consisting of sensing, array sensing-processing, and digital signal processing. The platform is based on the Cellular Neural/Nonlinear Network (CNN) paradigm. This article presents the implementation of a novel CNN-based segmentation algorithm onto the Bi-i system. Each part of the algorithm, along with the corresponding implementation on the hardware platform, is carefully described through the article. The experimental results, carried out for Foreman and Car-phone video sequences, highlight the feasibility of the approach, which provides a frame rate of about 26 frames/s. Comparisons with existing CNN-based methods show that the conceived approach is more accurate, thus representing a good trade-off between real-time requirements and accuracy.

  10. Segmentation algorithm via Cellular Neural/Nonlinear Network: implementation on Bio-inspired hardware platform

    Directory of Open Access Journals (Sweden)

    Vecchio Pietro

    2011-01-01

    Full Text Available Abstract The Bio-inspired (Bi-i Cellular Vision System is a computing platform consisting of sensing, array sensing-processing, and digital signal processing. The platform is based on the Cellular Neural/Nonlinear Network (CNN paradigm. This article presents the implementation of a novel CNN-based segmentation algorithm onto the Bi-i system. Each part of the algorithm, along with the corresponding implementation on the hardware platform, is carefully described through the article. The experimental results, carried out for Foreman and Car-phone video sequences, highlight the feasibility of the approach, which provides a frame rate of about 26 frames/s. Comparisons with existing CNN-based methods show that the conceived approach is more accurate, thus representing a good trade-off between real-time requirements and accuracy.

  11. Efficient Radio Resource Allocation in a GSM and GPRS Cellular Network

    Directory of Open Access Journals (Sweden)

    David Vannucci

    2004-10-01

    Full Text Available This paper investigates the effect of various radio resource allocation strategies in a GSM/GPRS cellular network. The most efficient resource allocation is analysed as a function of the proportion of circuit switched voice and packet switched data load. The Grade of Service and average packet delay is investigated as a function of the load, packet size and call duration. Additionally, the feasibility of using voice over Internet Protocol as opposed to circuit switched voice is investigated as a means to increase subscriber capacity per base station. The work is motivated firstly by the complexity of having both circuit switched and packet switched connectivity on GSM/GPRS mobile cellular system and secondly that an exclusively packet based access on GSM/GPRS has the potential to increase the efficiency of resource utilisation by suitably varying the channel allocation to exploit the characteristics of voice and data traffic.

  12. Energy-Efficient Relay Selection and Optimal Relay Location in Cooperative Cellular Networks with Asymmetric Traffic

    CERN Document Server

    Yang, Wei; Sun, Wanlu

    2010-01-01

    Energy-efficient communication is an important requirement for mobile relay networks due to the limited battery power of user terminals. This paper considers energy-efficient relaying schemes through selection of mobile relays in cooperative cellular systems with asymmetric traffic. The total energy consumption per information bit of the battery-powered terminals, i.e., the mobile station (MS) and the relay, is derived in theory. In the Joint Uplink and Downlink Relay Selection (JUDRS) scheme we proposed, the relay which minimizes the total energy consumption is selected. Additionally, the energy-efficient cooperation regions are investigated, and the optimal relay location is found for cooperative cellular systems with asymmetric traffic. The results reveal that the MS-relay and the relay-base station (BS) channels have different influence over relay selection decisions for optimal energy-efficiency. Information theoretic analysis of the diversity-multiplexing tradeoff (DMT) demonstrates that the proposed sc...

  13. Performance analysis of a handoff scheme for two-tier cellular CDMA networks

    Directory of Open Access Journals (Sweden)

    Ahmed Hamad

    2011-07-01

    Full Text Available A two-tier model is used in cellular networks to improve the Quality of Service (QoS, namely to reduce the blocking probability of new calls and the forced termination probability of ongoing calls. One tier, the microcells, is used for slow or stationary users, and the other, the macrocell, is used for high speed users. In Code-Division Multiple-Access (CDMA cellular systems, soft handoffs are supported, which provides ways for further QoS improvement. In this paper, we introduce such a way; namely, a channel borrowing scheme used in conjunction with a First-In-First-Out (FIFO queue in the macrocell tier. A multidimensional Markov chain to model the resulting system is established, and an iterative technique to find the steady-state probability distribution is utilized. This distribution is then used to find the performance measures of interest: new call blocking probability, and forced termination probability.

  14. 数字电视多业务传输平台设计与实现%Design and Implementation of Digital Television Multi-service Transmission Platform

    Institute of Scientific and Technical Information of China (English)

    李芳

    2012-01-01

    Aiming to the rapid development of interactive television on-demand business in the field of radio and television, the scheme of using Resilient Packet Ring (RPR) technology to build digital TV multi-service transport platform is introduced from the angle of the choice of network structure, business planning, protection mode, and the networking technology. The ease demonstrates the technical program can adapt to the transmission requirements of live TV and interactive TV, and provides a reference for the broadcasting industry building SDH transmission network.%针对交互电视点播业务在广播电视领域里的快速推进,从组网技术的选择、网络结构、业务规划、保护方式等角度,全面介绍利用弹性分组环(RPR)技术建设数字电视多业务传输平台的设计方案,并通过案例证明了该技术方案能适应直播电视和交互电视传输需求,为广电行业组建数字电视SDH传输网络提供参考.

  15. Multi-tier Network Performance Analysis using a Shotgun Cellular System

    CERN Document Server

    Madhusudhanan, Prasanna; Youjian,; Liu,; Brown, Timothy X; Baker, Kenneth R

    2011-01-01

    This paper studies the carrier-to-interference ratio (CIR) and carrier-to-interference-plus-noise ratio (CINR) performance at the mobile station (MS) within a multi-tier network composed of M tiers of wireless networks, with each tier modeled as the homogeneous n-dimensional (n-D, n=1,2, and 3) shotgun cellular system, where the base station (BS) distribution is given by the homogeneous Poisson point process in n-D. The CIR and CINR at the MS in a single tier network are thoroughly analyzed to simplify the analysis of the multi-tier network. For the multi-tier network with given system parameters, the following are the main results of this paper: (1) semi-analytical expressions for the tail probabilities of CIR and CINR; (2) a closed form expression for the tail probability of CIR in the range [1,Infinity); (3) a closed form expression for the tail probability of an approximation to CIR in the entire range [0,Infinity); (4) a lookup table based approach for obtaining the tail probability of CINR, and (5) the ...

  16. New Results on Almost Periodic Solution of Shunting Inhibitory Cellular Neural Networks with Continuously Distributed Delays

    Institute of Scientific and Technical Information of China (English)

    Jing Liu; Pei-Yong Zhu

    2008-01-01

    In this paper, the existence, uniqueness and global attractivity are discussed on almost periodic solution of SICNNs (shunting inhibitory cellular neural networks) with continuously distributed delays. By using the fixed point theorem, differential inequality technique and Lyapunov functional method, giving the new ranges of parameters, several sufficient conditions are obtained to ensure the existence, uniqueness and global attractivity of almost periodic solution. Compared with the previous studies, our methods are more effective for almost periodic solution analysis of SICNNs with continuously distributed delays. Some existing results have been improved and extended. In order to show the effectiveness of the obtained results, an example is given in this paper.

  17. Functional recognition imaging using artificial neural networks: applications to rapid cellular identification via broadband electromechanical response

    Energy Technology Data Exchange (ETDEWEB)

    Nikiforov, M P; Guo, S; Kalinin, S V; Jesse, S [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN 37831 (United States); Reukov, V V; Thompson, G L; Vertegel, A A, E-mail: sergei2@ornl.go [Department of Bioengineering, Clemson University, Clemson, SC 29634 (United States)

    2009-10-07

    Functional recognition imaging in scanning probe microscopy (SPM) using artificial neural network identification is demonstrated. This approach utilizes statistical analysis of complex SPM responses at a single spatial location to identify the target behavior, which is reminiscent of associative thinking in the human brain, obviating the need for analytical models. We demonstrate, as an example of recognition imaging, rapid identification of cellular organisms using the difference in electromechanical activity over a broad frequency range. Single-pixel identification of model Micrococcus lysodeikticus and Pseudomonas fluorescens bacteria is achieved, demonstrating the viability of the method.

  18. A synthesis procedure for associative memories based on space-varying cellular neural networks.

    Science.gov (United States)

    Park, J; Kim, H Y; Park, Y; Lee, S W

    2001-01-01

    In this paper, we consider the problem of realizing associative memories via space-varying CNNs (cellular neural networks). Based on some known results and a newly derived theorem for the CNN model, we propose a synthesis procedure for obtaining a space-varying CNN that can store given bipolar vectors with certain desirable properties. The major part of our synthesis procedure consists of solving generalized eigenvalue problems and/or linear matrix inequality problems, which can be efficiently solved by recently developed interior point methods. The validity of the proposed approach is illustrated by a design example.

  19. New color image encryption algorithm based on compound chaos mapping and hyperchaotic cellular neural network

    Science.gov (United States)

    Li, Jinqing; Bai, Fengming; Di, Xiaoqiang

    2013-01-01

    We propose an image encryption/decryption algorithm based on chaotic control parameter and hyperchaotic system with the composite permutation-diffusion structure. Compound chaos mapping is used to generate control parameters in the permutation stage. The high correlation between pixels is shuffled. In the diffusion stage, compound chaos mapping of different initial condition and control parameter generates the diffusion parameters, which are applied to hyperchaotic cellular neural networks. The diffusion key stream is obtained by this process and implements the pixels' diffusion. Compared with the existing methods, both simulation and statistical analysis of our proposed algorithm show that the algorithm has a good performance against attacks and meets the corresponding security level.

  20. Stability analysis of delayed cellular neural networks with and without noise perturbation

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xue-juan; WANG Guan-xiang; LIU Hua

    2008-01-01

    The stability of a class of delayed cellular neural networks (DCNN) with or without noise perturbation is studied.After presenting a simple and easily checkable condition for the global exponential stability of a deterministic system,we further investigate the case with noise perturbation.When DCNN is perturbed by external noise,the system is globally stable.An important fact is that,when the system is perturbed by internal noise,it is globally exponentially stable only if the total noise strength is within a certain bound.This is significant since the stochastic resonance phenomena have been found to exist in many nonlinear systems.

  1. Existence and stability of traveling wave solutions for multilayer cellular neural networks

    Science.gov (United States)

    Hsu, Cheng-Hsiung; Lin, Jian-Jhong; Yang, Tzi-Sheng

    2015-08-01

    The purpose of this article is to investigate the existence and stability of traveling wave solutions for one-dimensional multilayer cellular neural networks. We first establish the existence of traveling wave solutions using the truncated technique. Then we study the asymptotic behaviors of solutions for the Cauchy problem of the neural model. Applying two kinds of comparison principles and the weighed energy method, we show that all solutions of the Cauchy problem converge exponentially to the traveling wave solutions provided that the initial data belong to a suitable weighted space.

  2. Electric Energy Demand Forecast of Nanchang based on Cellular Genetic Algorithm and BP Neural Network

    Directory of Open Access Journals (Sweden)

    Cheng Yugui

    2013-07-01

    Full Text Available A kind of power forecast model combined cellular genetic algorithm with BP neural network was established in this article. Mid-long term power demand in urban areas was done load forecasting and analysis based on material object of the actual power consumption in urban areas of Nanchang. The results show that this method has the characteristic of the minimum training times, the shortest consumption time, the minimum error and the shortest operation time to obtain the best fitting effect.  

  3. A new method for the re-implementation of threshold logic functions with cellular neural networks.

    Science.gov (United States)

    Bénédic, Y; Wira, P; Mercklé, J

    2008-08-01

    A new strategy is presented for the implementation of threshold logic functions with binary-output Cellular Neural Networks (CNNs). The objective is to optimize the CNNs weights to develop a robust implementation. Hence, the concept of generative set is introduced as a convenient representation of any linearly separable Boolean function. Our analysis of threshold logic functions leads to a complete algorithm that automatically provides an optimized generative set. New weights are deduced and a more robust CNN template assuming the same function can thus be implemented. The strategy is illustrated by a detailed example.

  4. Initial Object Segmentation for Video Object Plane GenerationUsing Cellular Neural Networks

    Institute of Scientific and Technical Information of China (English)

    王慧; 杨高波; 张兆杨

    2003-01-01

    MPEG-4 is a basic tool for interactivity and manipulation of video sequences. Video object segmentation is a key issue in defining the content of any video sequence, which is often divided into two steps: initial object segmentation and object tracking. In this paper, an initial object segmentation method for video object plane(VOP) generation using color information is proposed. Based on 3 by 3 linear templates, a cellular neural network (CNN) is used to implemented object segmentation. The Experimental results arepresented to verify the efficiency and robustness of this approach.

  5. Evolving Transport Networks With Cellular Automata Models Inspired by Slime Mould.

    Science.gov (United States)

    Tsompanas, Michail-Antisthenis I; Sirakoulis, Georgios Ch; Adamatzky, Andrew I

    2015-09-01

    Man-made transport networks and their design are closely related to the shortest path problem and considered amongst the most debated problems of computational intelligence. Apart from using conventional or bio-inspired computer algorithms, many researchers tried to solve this kind of problem using biological computing substrates, gas-discharge solvers, prototypes of a mobile droplet, and hot ice computers. In this aspect, another example of biological computer is the plasmodium of acellular slime mould Physarum polycephalum (P. polycephalum), which is a large single cell visible by an unaided eye and has been proven as a reliable living substrate for implementing biological computing devices for computational geometry, graph-theoretical problems, and optimization and imitation of transport networks. Although P. polycephalum is easy to experiment with, computing devices built with the living slime mould are extremely slow; it takes slime mould days to execute a computation. Consequently, mapping key computing mechanisms of the slime mould onto silicon would allow us to produce efficient bio-inspired computing devices to tackle with hard to solve computational intelligence problems like the aforementioned. Toward this direction, a cellular automaton (CA)-based, Physarum-inspired, network designing model is proposed. This novel CA-based model is inspired by the propagating strategy, the formation of tubular networks, and the computing abilities of the plasmodium of P. polycephalum. The results delivered by the CA model demonstrate a good match with several previously published results of experimental laboratory studies on imitation of man-made transport networks with P. polycephalum. Consequently, the proposed CA model can be used as a virtual, easy-to-access, and biomimicking laboratory emulator that will economize large time periods needed for biological experiments while producing networks almost identical to the tubular networks of the real-slime mould.

  6. Nearly Optimal Resource Allocation for Downlink OFDMA in 2-D Cellular Networks

    CERN Document Server

    Ksairi, Nassar; Ciblat, Philippe

    2010-01-01

    In this paper, we propose a resource allocation algorithm for the downlink of sectorized two-dimensional (2-D) OFDMA cellular networks assuming statistical Channel State Information (CSI) and fractional frequency reuse. The proposed algorithm can be implemented in a distributed fashion without the need to any central controlling units. Its performance is analyzed assuming fast fading Rayleigh channels and Gaussian distributed multicell interference. We show that the transmit power of this simple algorithm tends, as the number of users grows to infinity, to the same limit as the minimal power required to satisfy all users' rate requirements i.e., the proposed resource allocation algorithm is asymptotically optimal. As a byproduct of this asymptotic analysis, we characterize a relevant value of the reuse factor that only depends on an average state of the network.

  7. TDMA Achieves the Optimal Diversity Gain in Relay-Assisted Cellular Networks

    CERN Document Server

    Bi, Suzhi; Zhang,

    2011-01-01

    In multi-access wireless networks, transmission scheduling is a key component that determines the efficiency and fairness of wireless spectrum allocation. At one extreme, greedy opportunistic scheduling that allocates airtime to the user with the largest instantaneous channel gain achieves the optimal spectrum efficiency and transmission reliability but the poorest user-level fairness. At the other extreme, fixed TDMA scheduling achieves the fairest airtime allocation but the lowest spectrum efficiency and transmission reliability. To balance the two competing objectives, extensive research efforts have been spent on designing opportunistic scheduling schemes that reach certain tradeoff points between the two extremes. In this paper and in contrast to the conventional wisdom, we find that in relay-assisted cellular networks, fixed TDMA achieves the same optimal diversity gain as greedy opportunistic scheduling. In addition, by incorporating very limited opportunism, a simple relaxed-TDMA scheme asymptotically...

  8. Combined Base Station Association and Power Control in Multi-channel Cellular Networks

    CERN Document Server

    Singh, Chandramani; Sundaresan, Rajesh

    2011-01-01

    A combined base station association and power control problem is studied for the uplink of multichannel multicell cellular networks, in which each channel is used by exactly one cell (i.e., base station). A distributed association and power update algorithm is proposed and shown to converge to a Nash equilibrium of a noncooperative game. We consider network models with discrete mobiles (yielding an atomic congestion game), as well as a continuum of mobiles (yielding a population game). We find that the equilibria need not be Pareto efficient, nor need they be system optimal. To address the lack of system optimality, we propose pricing mechanisms. It is shown that these mechanisms can be implemented in a distributed fashion.

  9. Stability Analysis of a Class of Three-Neuron Delayed Cellular Neural Network

    Directory of Open Access Journals (Sweden)

    Poulami D. Gupta

    2010-01-01

    Full Text Available Problem statement: In this study linear stability of a class of three neuron cellular network with transmission delay had been studied. Approach: The model for the problem was first presented. The problem is then formulated analytically and numerical simulations pertaining to the model are carried out. Results: A necessary and sufficient condition for asymptotic stability of trivial steady state in the absence of delay is derived. Then a delay dependent sufficient condition for local asymptotic stability of trivial, steady state and sufficient condition for no stability switching of trivial steady for such a network are derived. Numerical simulation results of the model were presented. Conclusion/Recommendations: From numerical simulation, it appears that there may be a possibility of multiple steady states of the model. It may be possible to investigate the condition for the existence of periodic solutions of the non-linear model analytically.

  10. Stability analysis of switched cellular neural networks: A mode-dependent average dwell time approach.

    Science.gov (United States)

    Huang, Chuangxia; Cao, Jie; Cao, Jinde

    2016-10-01

    This paper addresses the exponential stability of switched cellular neural networks by using the mode-dependent average dwell time (MDADT) approach. This method is quite different from the traditional average dwell time (ADT) method in permitting each subsystem to have its own average dwell time. Detailed investigations have been carried out for two cases. One is that all subsystems are stable and the other is that stable subsystems coexist with unstable subsystems. By employing Lyapunov functionals, linear matrix inequalities (LMIs), Jessen-type inequality, Wirtinger-based inequality, reciprocally convex approach, we derived some novel and less conservative conditions on exponential stability of the networks. Comparing to ADT, the proposed MDADT show that the minimal dwell time of each subsystem is smaller and the switched system stabilizes faster. The obtained results extend and improve some existing ones. Moreover, the validness and effectiveness of these results are demonstrated through numerical simulations.

  11. Long term country-wide rainfall monitoring employing cellular communication networks

    Science.gov (United States)

    Overeem, Aart; Leijnse, Hidde; Uijlenhoet, Remko

    2013-04-01

    Accurate rainfall observations with high spatial and temporal resolutions are needed for hydrological applications, agriculture, meteorology, and climate monitoring. However, the majority of the land surface of the earth lacks accurate rainfall information and the number of rain gauges is even severely declining in Europe, South-America, and Africa. This calls for alternative sources of rainfall information. Various studies have shown that microwave links from operational cellular telecommunication networks may be employed for rainfall monitoring. Such networks cover 20% of the land surface of the earth and have a high density, especially in urban areas. The basic principle of rainfall monitoring using microwave links is as follows. Rainfall attenuates the electromagnetic signals transmitted from one telephone tower to another. By measuring the received power at one end of a microwave link as a function of time, the path-integrated attenuation due to rainfall can be calculated. Previous studies have shown that average rainfall intensities over the length of a link can be derived from the path-integrated attenuation. This is particularly interesting for those countries where few surface rainfall observations are available. Here we present preliminary results of long term country-wide rainfall monitoring employing cellular communication networks. A dataset from a commercial microwave link network over the Netherlands is analyzed, containing data from an unprecedented number of links (~ 2000) covering the land surface of the Netherlands (35500 square kilometres). This dataset spans from January 2011 through October 2012. Daily rainfall maps (1 km spatial resolution) are derived from the microwave link data and compared to maps from a gauge-adjusted radar dataset. The performance of the rainfall retrieval algorithm will be investigated, particularly a possible seasonal dependence.

  12. On Green Cognitive Radio Cellular Networks: Dynamic Spectrum and Operation Management

    KAUST Repository

    Sboui, Lokman

    2016-07-18

    We study a profit maximization problem related to cognitive radio cellular networks in an environmentally- friendly framework. The objective of the primary network (PN) and secondary network (SN) is to maximize their profits while respecting a certain carbon dioxide (CO2) emissions threshold. In this study, the PN can switch off some of its base stations (BSs) powered by mircogrids, and hence leases the spectrum in the corresponding cells, to reduce its footprint. The corresponding users are roamed to the SN infrastructure. In return, the SN receives a certain roaming cost and its users can freely exploit the spectrum. We study two scenarios in which the profits are either separately or jointly maximized. In the disjoint maximization problem, two low complexity algorithms for PN and SN BS on/off switching are proposed to maximize the profit per CO2 emissions utility and determine the amount of the shared bandwidth. In the joint maximization approach, the low complexity algorithm is based on maximizing the sum of weighted profits per CO2. Selected numerical results illustrate the collaboration performance versus various system parameters. We show that the proposed algorithms achieve performances close to those obtained with the exhaustive search method, and that the roaming price and the renewable energy availability are crucial parameters that control the collaboration of both networks.

  13. Effect of crystals and fibrous network polymer additives on cellular morphology of microcellular foams

    Science.gov (United States)

    Miyamoto, Ryoma; Utano, Tatsumi; Yasuhara, Shunya; Ishihara, Shota; Ohshima, Masahiro

    2015-05-01

    In this study, the core-back foam injection molding was used for preparing microcelluar polypropylene (PP) foam with either a 1,3:2,4 bis-O-(4-methylbenzylidene)-D-sorbitol gelling agent (Gel-all MD) or a fibros network polymer additive (Metablen 3000). Both agent and addiive could effectively control the celluar morphology in foams but somehow different ways. In course of cooling the polymer with Gel-all MD in the mold caity, the agent enhanced the crystal nucleation and resulted in the large number of small crystals. The crystals acted as effective bubble nucleation agent in foaming process. Thus, the agent reduced the cell size and increased the cell density, drastically. Furthermore, the small crystals provided an inhomogenuity to the expanding cell wall and produced the high open cell content with nano-scale fibril structure. Gell-all as well as Metablene 3000 formed a gel-like fibrous network in melt. The network increased the elongational viscosity and tended to prevent the cell wall from breaking up. The foaming temperature window was widened by the presence of the network. Especially, the temperature window where the macro-fibrous structure was formed was expanded to the higher temperature. The effects of crystal nucleating agent and PTFE on crystals' size and number, viscoelsticity, rheological propreties of PP and cellular morphology were compared and thorougly investigated.

  14. Inferring cellular regulatory networks with Bayesian model averaging for linear regression (BMALR).

    Science.gov (United States)

    Huang, Xun; Zi, Zhike

    2014-08-01

    Bayesian network and linear regression methods have been widely applied to reconstruct cellular regulatory networks. In this work, we propose a Bayesian model averaging for linear regression (BMALR) method to infer molecular interactions in biological systems. This method uses a new closed form solution to compute the posterior probabilities of the edges from regulators to the target gene within a hybrid framework of Bayesian model averaging and linear regression methods. We have assessed the performance of BMALR by benchmarking on both in silico DREAM datasets and real experimental datasets. The results show that BMALR achieves both high prediction accuracy and high computational efficiency across different benchmarks. A pre-processing of the datasets with the log transformation can further improve the performance of BMALR, leading to a new top overall performance. In addition, BMALR can achieve robust high performance in community predictions when it is combined with other competing methods. The proposed method BMALR is competitive compared to the existing network inference methods. Therefore, BMALR will be useful to infer regulatory interactions in biological networks. A free open source software tool for the BMALR algorithm is available at https://sites.google.com/site/bmalr4netinfer/.

  15. Reuse Partitioning-Based Frequency Assignment in Fixed Two-Hop Relay Cellular Network

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In relay cellular network, relay links will consume extra frequency resources, which makes radio resource allocation become more complex and important. A new frequency allocation scheme is proposed to increase cell capacity and improve signal-to-interference ratio (SIR) of users located at cell edges. By dividing cell into different parts and configuring each of these parts with a unique reuse factor, this scheme improves spectral utilization efficiency and avoids inter-cell interference effectively. Optimal combinations of reuse factors and locations of relay nodes are also addressed and investigated. Computer simulation results show that, by employing the proposed scheme, maximum cell capacity gains of about 50%, 35% and 30% can be achieved in comparison with conventional cellular network scheme, traditional reuse partitioning scheme and reuse-adjacent-cell-frequencies scheme, respectively. Moreover, since in the proposed scheme resources are dynamically allocated among relay nodes, more benefits can be obtained in comparison with fixed resource allocation schemes under non-uniform traffic distribution.

  16. Uniqueness and stability of traveling waves for cellular neural networks with multiple delays

    Science.gov (United States)

    Yu, Zhi-Xian; Mei, Ming

    2016-01-01

    In this paper, we investigate the properties of traveling waves to a class of lattice differential equations for cellular neural networks with multiple delays. Following the previous study [38] on the existence of the traveling waves, here we focus on the uniqueness and the stability of these traveling waves. First of all, by establishing the a priori asymptotic behavior of traveling waves and applying Ikehara's theorem, we prove the uniqueness (up to translation) of traveling waves ϕ (n - ct) with c ≤c* for the cellular neural networks with multiple delays, where c* < 0 is the critical wave speed. Then, by the weighted energy method together with the squeezing technique, we further show the global stability of all non-critical traveling waves for this model, that is, for all monotone waves with the speed c

  17. Energy Management Optimization for Cellular Networks under Renewable Energy Generation Uncertainty

    KAUST Repository

    Rached, Nadhir Ben

    2017-03-28

    The integration of renewable energy (RE) as an alternative power source for cellular networks has been deeply investigated in literature. However, RE generation is often assumed to be deterministic; an impractical assumption for realistic scenarios. In this paper, an efficient energy procurement strategy for cellular networks powered simultaneously by the smart grid (SG) and locally deployed RE sources characterized by uncertain processes is proposed. For a one-day operation cycle, the mobile operator aims to reduce its total energy cost by optimizing the amounts of energy to be procured from the local RE sources and SG at each time period. Additionally, it aims to determine the amount of extra generated RE to be sold back to SG. A chance constrained optimization is first proposed to deal with the RE generation uncertainty. Then, two convex approximation approaches: Chernoff and Chebyshev methods, characterized by different levels of knowledge about the RE generation, are developed to determine the energy procurement strategy for different risk levels. In addition, their performances are analyzed for various daily scenarios through selected simulation results. It is shown that the higher complex Chernoff method outperforms the Chebyshev one for different risk levels set by the operator.

  18. Robust Nash Dynamic Game Strategy for User Cooperation Energy Efficiency in Wireless Cellular Networks

    Directory of Open Access Journals (Sweden)

    Shuhuan Wen

    2012-01-01

    Full Text Available Recently, there is an emerging trend of addressing “energy efficiency” aspect of wireless communications. It has been shown that cooperating users relay each other's information to improve data rates. The energy is limited in the wireless cellular network, but the mobile users refuse to relay. This paper presents an approach that encourages user cooperation in order to improve the energy efficiency. The game theory is an efficient method to solve such conflicts. We present a cellular framework in which two mobile users, who desire to communicate with a common base station, may cooperate via decode-and-forward relaying. In the case of imperfect information assumption, cooperative Nash dynamic game is used between the two users' cooperation to tackle the decision making problems: whether to cooperate and how to cooperate in wireless networks. The scheme based on “cooperative game theory” can achieve general pareto-optimal performance for cooperative games, and thus, maximize the entire system payoff while maintaining fairness.

  19. Coordinated Precoding for D2D Communications Underlay Uplink MIMO Cellular Networks

    Directory of Open Access Journals (Sweden)

    Bing Fang

    2016-01-01

    Full Text Available We study the coordinated precoding problem for device-to-device (D2D communications underlay multiple-input multiple-output (MIMO cellular networks. The system model considered here constitutes multiple D2D user pairs attempting to share the uplink radio resources of a cellular network. We first formulate the coordinated precoding problem for the D2D user pairs as a sum-rate maximization (SRM problem, which is subject to a total interference power constraint imposed to protect the base station (BS and individual transmit power budgets available for each D2D user pair. Since the formulated SRM problem is nonconvex in general, we reformulate it as a difference convex- (DC- type programming problem, which can be iteratively solved by employing the famous successive convex approximation (SCA method. Moreover, a proximal-point-based regularization approach is also pursued here to ensure the convergence of the proposed algorithm. Interestingly, the centralized precoding algorithm can also lend itself to a distributed implementation. By introducing a price-based interference management mechanism, we reformulate the coordinated precoding problem as a Stackelberg game. Then, a distributed precoding algorithm is developed based on the concept of Stackelberg equilibrium (SE. Finally, numerical simulations are also provided to demonstrate the proposed algorithms. Results show that our algorithms can converge fast to a satisfactory solution with guaranteed convergence.

  20. Condition monitoring of 3G cellular networks through competitive neural models.

    Science.gov (United States)

    Barreto, Guilherme A; Mota, João C M; Souza, Luis G M; Frota, Rewbenio A; Aguayo, Leonardo

    2005-09-01

    We develop an unsupervised approach to condition monitoring of cellular networks using competitive neural algorithms. Training is carried out with state vectors representing the normal functioning of a simulated CDMA2000 network. Once training is completed, global and local normality profiles (NPs) are built from the distribution of quantization errors of the training state vectors and their components, respectively. The global NP is used to evaluate the overall condition of the cellular system. If abnormal behavior is detected, local NPs are used in a component-wise fashion to find abnormal state variables. Anomaly detection tests are performed via percentile-based confidence intervals computed over the global and local NPs. We compared the performance of four competitive algorithms [winner-take-all (WTA), frequency-sensitive competitive learning (FSCL), self-organizing map (SOM), and neural-gas algorithm (NGA)] and the results suggest that the joint use of global and local NPs is more efficient and more robust than current single-threshold methods.

  1. On the Achievability of Interference Alignment for Three-Cell Multi-User MIMO Cellular Networks

    CERN Document Server

    Ma, Yanjun; Chen, Rui; Liu, Qin

    2011-01-01

    An interference alignment (IA) based scheme is proposed by joint design of transmit precoding matrices and receive beamforming matrices for the three-cell Multi-User MIMO (MU-MIMO) cellular network with constant channel between each node, where each base station (BS) is equipped with $M$ antennas, each mobile station (MS) is equipped with $N$ antennas, and $M \\geq N$. We assume $K$ cell-edge users are served per cell simultaneously where $K>1$, and BS sends $d$ data streams to each of its users. It is shown that $\\frac{M}{2}$ degrees of freedom (DoF) is achievable per cell when $M=N$, $K=\\frac{M}{2d}$, and $M$ is divisible by 2d, and $Kd$ DoF is achievable per cell if $M =KN$ and $d \\leq \\lfloor \\frac{M}{3K-1} \\rfloor$ or if $(3K -1)d \\leq M < KN $ and $d \\leq 3(KN-M)$. Furthermore, when there have extra dimensions at BSs, a space-division hybrid (SDH) scheme is proposed for the three-cell MU-MIMO cellular network, where cell-edge users and cell-center users are served simultaneously. Cell-edge users work ...

  2. Mobility-Aware Modeling and Analysis of Dense Cellular Networks With $C$ -Plane/ $U$ -Plane Split Architecture

    KAUST Repository

    Ibrahim, Hazem

    2016-09-19

    The unrelenting increase in the population of mobile users and their traffic demands drive cellular network operators to densify their network infrastructure. Network densification shrinks the footprint of base stations (BSs) and reduces the number of users associated with each BS, leading to an improved spatial frequency reuse and spectral efficiency, and thus, higher network capacity. However, the densification gain comes at the expense of higher handover rates and network control overhead. Hence, user’s mobility can diminish or even nullifies the foreseen densification gain. In this context, splitting the control plane ( C -plane) and user plane ( U -plane) is proposed as a potential solution to harvest densification gain with reduced cost in terms of handover rate and network control overhead. In this paper, we use stochastic geometry to develop a tractable mobility-aware model for a two-tier downlink cellular network with ultra-dense small cells and C -plane/ U -plane split architecture. The developed model is then used to quantify the effect of mobility on the foreseen densification gain with and without C -plane/ U -plane split. To this end, we shed light on the handover problem in dense cellular environments, show scenarios where the network fails to support certain mobility profiles, and obtain network design insights.

  3. Distributed Compression for the Uplink of a Backhaul-Constrained Coordinated Cellular Network

    CERN Document Server

    del Coso, Aitor

    2008-01-01

    We consider a backhaul-constrained coordinated cellular network. That is, a single-frequency network with $N+1$ multi-antenna base stations (BSs) that cooperate in order to decode the users' data, and that are linked by means of a common lossless backhaul, of limited capacity $\\mathrm{R}$. To implement receive cooperation, we propose distributed compression: $N$ BSs, upon receiving their signals, compress them using a multi-source lossy compression code. Then, they send the compressed vectors to a central BS, which performs users' decoding. Distributed Wyner-Ziv coding is proposed to be used, and is optimally designed in this work. The first part of the paper is devoted to a network with a unique multi-antenna user, that transmits a predefined Gaussian space-time codeword. For such a scenario, the compression codebooks at the BSs are optimized, considering the user's achievable rate as the performance metric. In particular, for $N = 1$ the optimum codebook distribution is derived in closed form, while for $N>...

  4. Knowledge-guided fuzzy logic modeling to infer cellular signaling networks from proteomic data

    Science.gov (United States)

    Liu, Hui; Zhang, Fan; Mishra, Shital Kumar; Zhou, Shuigeng; Zheng, Jie

    2016-01-01

    Modeling of signaling pathways is crucial for understanding and predicting cellular responses to drug treatments. However, canonical signaling pathways curated from literature are seldom context-specific and thus can hardly predict cell type-specific response to external perturbations; purely data-driven methods also have drawbacks such as limited biological interpretability. Therefore, hybrid methods that can integrate prior knowledge and real data for network inference are highly desirable. In this paper, we propose a knowledge-guided fuzzy logic network model to infer signaling pathways by exploiting both prior knowledge and time-series data. In particular, the dynamic time warping algorithm is employed to measure the goodness of fit between experimental and predicted data, so that our method can model temporally-ordered experimental observations. We evaluated the proposed method on a synthetic dataset and two real phosphoproteomic datasets. The experimental results demonstrate that our model can uncover drug-induced alterations in signaling pathways in cancer cells. Compared with existing hybrid models, our method can model feedback loops so that the dynamical mechanisms of signaling networks can be uncovered from time-series data. By calibrating generic models of signaling pathways against real data, our method supports precise predictions of context-specific anticancer drug effects, which is an important step towards precision medicine. PMID:27774993

  5. Quality of service improvement, Handoff Prioritization and Channel utilization for Cellular Network

    Directory of Open Access Journals (Sweden)

    Anoop Kumar Gangwar

    2014-10-01

    Full Text Available In this paper Call admission control (CAC is a significant component in wireless networks to promise quality of service requirements and also to improve the network flexibility. The reliability is measured in terms of quality of service (QoS and grade of service (GoS. GoS is a call‐level factor, which comprises of a new call blocking probability and handoff call blocking probability. So a robust Call Admission and Power Control Mechanism are desired. An admission control method considering the quality of service (QoS requirements is accountable for deciding whether an incoming call/connection can be accepted or not. One major challenge in designing a CAC creates due to the fact that the cellular network has to service two major types of calls: new calls and handoff calls. The QoS performances related to these two types of calls are generally measured by new call blocking probability and handoff call dropping probability. Our work advance the dropping and handoff loss probabilities and present a coherent framework for comparative studies of presented approaches, but also helps future researches and developments of new call admission policies.

  6. Hybrid Access Femtocells in Overlaid MIMO Cellular Networks with Transmit Selection under Poisson Field Interference

    KAUST Repository

    Abdel Nabi, Amr A

    2017-09-21

    This paper analyzes the performance of hybrid control-access schemes for small cells (such as femtocells) in the context of two-tier overlaid cellular networks. The proposed hybrid access schemes allow for sharing the same downlink resources between the small-cell network and the original macrocell network, and their mode of operations are characterized considering post-processed signal-to-interference-plus-noise ratios (SINRs) or pre-processed interference-aware operation. The work presents a detailed treatment of achieved performance of a desired user that benefits from MIMO arrays configuration through the use of transmit antenna selection (TAS) and maximal ratio combining (MRC) in the presence of Poisson field interference processes on spatial links. Furthermore, based on the interference awareness at the desired user, two TAS approaches are treated, which are the signal-to-noise (SNR)-based selection and SINR-based selection. The analysis is generalized to address the cases of highly-correlated and un-correlated aggregated interference on different transmit channels. In addition, the effect of delayed TAS due to imperfect feedback and the impact of arbitrary TAS processing are investigated. The analytical results are validated by simulations, to clarify some of the main outcomes herein.

  7. Knowledge-guided fuzzy logic modeling to infer cellular signaling networks from proteomic data

    Science.gov (United States)

    Liu, Hui; Zhang, Fan; Mishra, Shital Kumar; Zhou, Shuigeng; Zheng, Jie

    2016-10-01

    Modeling of signaling pathways is crucial for understanding and predicting cellular responses to drug treatments. However, canonical signaling pathways curated from literature are seldom context-specific and thus can hardly predict cell type-specific response to external perturbations; purely data-driven methods also have drawbacks such as limited biological interpretability. Therefore, hybrid methods that can integrate prior knowledge and real data for network inference are highly desirable. In this paper, we propose a knowledge-guided fuzzy logic network model to infer signaling pathways by exploiting both prior knowledge and time-series data. In particular, the dynamic time warping algorithm is employed to measure the goodness of fit between experimental and predicted data, so that our method can model temporally-ordered experimental observations. We evaluated the proposed method on a synthetic dataset and two real phosphoproteomic datasets. The experimental results demonstrate that our model can uncover drug-induced alterations in signaling pathways in cancer cells. Compared with existing hybrid models, our method can model feedback loops so that the dynamical mechanisms of signaling networks can be uncovered from time-series data. By calibrating generic models of signaling pathways against real data, our method supports precise predictions of context-specific anticancer drug effects, which is an important step towards precision medicine.

  8. Proof-of-Concept of a Millimeter-Wave Integrated Heterogeneous Network for 5G Cellular.

    Science.gov (United States)

    Okasaka, Shozo; Weiler, Richard J; Keusgen, Wilhelm; Pudeyev, Andrey; Maltsev, Alexander; Karls, Ingolf; Sakaguchi, Kei

    2016-08-25

    The fifth-generation mobile networks (5G) will not only enhance mobile broadband services, but also enable connectivity for a massive number of Internet-of-Things devices, such as wireless sensors, meters or actuators. Thus, 5G is expected to achieve a 1000-fold or more increase in capacity over 4G. The use of the millimeter-wave (mmWave) spectrum is a key enabler to allowing 5G to achieve such enhancement in capacity. To fully utilize the mmWave spectrum, 5G is expected to adopt a heterogeneous network (HetNet) architecture, wherein mmWave small cells are overlaid onto a conventional macro-cellular network. In the mmWave-integrated HetNet, splitting of the control plane (CP) and user plane (UP) will allow continuous connectivity and increase the capacity of the mmWave small cells. mmWave communication can be used not only for access linking, but also for wireless backhaul linking, which will facilitate the installation of mmWave small cells. In this study, a proof-of-concept (PoC) was conducted to demonstrate the practicality of a prototype mmWave-integrated HetNet, using mmWave technologies for both backhaul and access.

  9. Proof-of-Concept of a Millimeter-Wave Integrated Heterogeneous Network for 5G Cellular

    Directory of Open Access Journals (Sweden)

    Shozo Okasaka

    2016-08-01

    Full Text Available The fifth-generation mobile networks (5G will not only enhance mobile broadband services, but also enable connectivity for a massive number of Internet-of-Things devices, such as wireless sensors, meters or actuators. Thus, 5G is expected to achieve a 1000-fold or more increase in capacity over 4G. The use of the millimeter-wave (mmWave spectrum is a key enabler to allowing 5G to achieve such enhancement in capacity. To fully utilize the mmWave spectrum, 5G is expected to adopt a heterogeneous network (HetNet architecture, wherein mmWave small cells are overlaid onto a conventional macro-cellular network. In the mmWave-integrated HetNet, splitting of the control plane (CP and user plane (UP will allow continuous connectivity and increase the capacity of the mmWave small cells. mmWave communication can be used not only for access linking, but also for wireless backhaul linking, which will facilitate the installation of mmWave small cells. In this study, a proof-of-concept (PoC was conducted to demonstrate the practicality of a prototype mmWave-integrated HetNet, using mmWave technologies for both backhaul and access.

  10. Load-aware modeling for uplink cellular networks in a multi-channel environment

    KAUST Repository

    AlAmmouri, Ahmad

    2014-09-01

    We exploit tools from stochastic geometry to develop a tractable analytical approach for modeling uplink cellular networks. The developed model is load aware and accounts for per-user power control as well as the limited transmit power constraint for the users\\' equipment (UEs). The proposed analytical paradigm is based on a simple per-user power control scheme in which each user inverts his path-loss such that the signal is received at his serving base station (BS) with a certain power threshold ρ Due to the limited transmit power of the UEs, users that cannot invert their path-loss to their serving BSs are allowed to transmit with their maximum transmit power. We show that the proposed power control scheme not only provides a balanced cell center and cell edge user performance, it also facilitates the analysis when compared to the state-of-the-art approaches in the literature. To this end, we discuss how to manipulate the design variable ρ in response to the network parameters to optimize one or more of the performance metrics such as the outage probability, the network capacity, and the energy efficiency.

  11. A New Kind of Cellular Network%一种新的元胞网络模型

    Institute of Scientific and Technical Information of China (English)

    李学伟; 孙有发; 吴今培

    2011-01-01

    用元胞替换传统人工神经网络中的神经元,以局部连接取代相邻层级元胞之间的全连接,用规则演化算法替代BP算法,建立元胞网络模型.设计了元胞网络的训练过程:内嵌的遗传算法用于寻优各元胞状态离散化边界值以及元胞网络拓扑结构.以一个红酒分类基准数据为例,检验了元胞网络的学习性能和分类性能,获得了较为满意的结果.%A novel concept of cellular network is proposed. The cellular network is constructed based on the traditional artificial neural network by replacing the neurons with ceils, replacing the full connections among cells with partial connections, and replacing the back-propagation algorithm with rule-evolution algorithm. The training process of cellular network is also designed. The embedded genetic algorithm is to search for the optimal parameters and structures of the network. Finally, the cellular network is applied to a benchmark data set (classification of Italy's red wine), and is validated to be of good performances of learning and predicting.

  12. Root Cause Analysis and New Practical Schemes for better Accessing and Establishing of Dedicated Control Channel in Cellular Networks

    Directory of Open Access Journals (Sweden)

    Mohammad Rasoul Tanhatalab

    2013-12-01

    Full Text Available The Dedicated Control Channel (DCCH plays an important role in all generations of cellular networks, such as, GSM , HSPA and LTE ; through this logical channel, some information between user equipment and network can be carried. It should be considered that accessing to the DCCH is the entry gate of entrance to the every cellular network; and without a successful DCCH access call-setup process will not be possible. Hence, DCCH channel accessing is one of the most critical issues that RF planner and optimization engineers must consider. More than this, these schemes can contribute to achieve some algorithms in SON for ameliorating the DCCH accessing and serving better services at 4G. In this paper, a real fundamentally established cellular network (GSM is surveyed and its radio frequency network performance is evaluated and presented on the basis of KPI parameters in general. Furthermore, the DCCH Access Success in particular and different issues, findings, trials and improvements have been summarized. Also, recommendations have been listed to correlate the practical aspects of RF optimization, which affect the improvement of DCCH Access Success rate in cellular networks.

  13. Global exponential stability analysis of cellular neural networks with multiple time delays

    Institute of Scientific and Technical Information of China (English)

    Zhanshan WANG; Huaguang ZHANG

    2007-01-01

    Global exponential stability problems are investigated for cellular neural networks (CNN) with multiple time-varying delays. Several new criteria in linear matrix inequality form or in algebraic form are presented to ascertain the uniqueness and global exponential stability of the equilibrium point for CNN with multiple time-varying delays and with constant time delays. The proposed method has the advantage of considering the difference of neuronal excitatory and inhibitory effects, which is also computationally efficient as it can be solved numerically using the recently developed interior-point algorithm or be checked using simple algebraic calculation. In addition, the proposed results generalize and improve upon some previous works. Two numerical examples are used to show the effectiveness of the obtained results.

  14. Extended LaSalle's Invariance Principle for Full-Range Cellular Neural Networks

    Science.gov (United States)

    Di Marco, Mauro; Forti, Mauro; Grazzini, Massimo; Pancioni, Luca

    2009-12-01

    In several relevant applications to the solution of signal processing tasks in real time, a cellular neural network (CNN) is required to be convergent, that is, each solution should tend toward some equilibrium point. The paper develops a Lyapunov method, which is based on a generalized version of LaSalle's invariance principle, for studying convergence and stability of the differential inclusions modeling the dynamics of the full-range (FR) model of CNNs. The applicability of the method is demonstrated by obtaining a rigorous proof of convergence for symmetric FR-CNNs. The proof, which is a direct consequence of the fact that a symmetric FR-CNN admits a strict Lyapunov function, is much more simple than the corresponding proof of convergence for symmetric standard CNNs.

  15. Extended LaSalle's Invariance Principle for Full-Range Cellular Neural Networks

    Directory of Open Access Journals (Sweden)

    Mauro Di Marco

    2009-01-01

    Full Text Available In several relevant applications to the solution of signal processing tasks in real time, a cellular neural network (CNN is required to be convergent, that is, each solution should tend toward some equilibrium point. The paper develops a Lyapunov method, which is based on a generalized version of LaSalle's invariance principle, for studying convergence and stability of the differential inclusions modeling the dynamics of the full-range (FR model of CNNs. The applicability of the method is demonstrated by obtaining a rigorous proof of convergence for symmetric FR-CNNs. The proof, which is a direct consequence of the fact that a symmetric FR-CNN admits a strict Lyapunov function, is much more simple than the corresponding proof of convergence for symmetric standard CNNs.

  16. Multiscale systems analysis of root growth and development: modeling beyond the network and cellular scales.

    Science.gov (United States)

    Band, Leah R; Fozard, John A; Godin, Christophe; Jensen, Oliver E; Pridmore, Tony; Bennett, Malcolm J; King, John R

    2012-10-01

    Over recent decades, we have gained detailed knowledge of many processes involved in root growth and development. However, with this knowledge come increasing complexity and an increasing need for mechanistic modeling to understand how those individual processes interact. One major challenge is in relating genotypes to phenotypes, requiring us to move beyond the network and cellular scales, to use multiscale modeling to predict emergent dynamics at the tissue and organ levels. In this review, we highlight recent developments in multiscale modeling, illustrating how these are generating new mechanistic insights into the regulation of root growth and development. We consider how these models are motivating new biological data analysis and explore directions for future research. This modeling progress will be crucial as we move from a qualitative to an increasingly quantitative understanding of root biology, generating predictive tools that accelerate the development of improved crop varieties.

  17. Adaptive call admission control and resource allocation in multi server wireless/cellular network

    Science.gov (United States)

    Jain, Madhu; Mittal, Ragini

    2016-11-01

    The ever increasing demand of the subscribers has put pressure on the capacity of wireless networks around the world. To utilize the scare resources, in the present paper we propose an optimal allocation scheme for an integrated wireless/cellular model with handoff priority and handoff guarantee services. The suggested algorithm optimally allocates the resources in each cell and dynamically adjust threshold to control the admission. To give the priority to handoff calls over the new calls, the provision of guard channels and subrating scheme is taken into consideration. The handoff voice call may balk and renege from the system while waiting in the buffer. An iterative algorithm is implemented to generate the arrival rate of the handoff calls in each cell. Various performance indices are established in term of steady state probabilities. The sensitivity analysis has also been carried out to examine the tractability of algorithms and to explore the effects of system descriptors on the performance indices.

  18. Cooperative Beamforming for Dual-Hop Amplify-and-Forward Multi-Antenna Relaying Cellular Networks

    CERN Document Server

    Xing, Chengwen; Ma, shaodan; Wu, Yik-Chung

    2011-01-01

    In this paper, linear beamforming design for amplify-and-forward relaying cellular networks is considered, in which base station, relay station and mobile terminals are all equipped with multiple antennas. The design is based on minimum mean-square-error criterion, and both uplink and downlink scenarios are considered. It is found that the downlink and uplink beamforming design problems are in the same form, and iterative algorithms with the same structure can be used to solve the design problems. For the specific cases of fully loaded or overloaded uplink systems, a novel algorithm is derived and its relationships with several existing beamforming design algorithms for conventional MIMO or multiuser systems are revealed. Simulation results are presented to demonstrate the performance advantage of the proposed design algorithms.

  19. A Metric for Secrecy-Energy Efficiency Tradeoff Evaluation in 3GPP Cellular Networks

    Directory of Open Access Journals (Sweden)

    Fabio Ciabini

    2016-10-01

    Full Text Available Physical-layer security is now being considered for information protection in future wireless communications. However, a better understanding of the inherent secrecy of wireless systems under more realistic conditions, with a specific attention to the relative energy consumption costs, has to be pursued. This paper aims at proposing new analysis tools and investigating the relation between secrecy capacity and energy consumption in a 3rd Generation Partnership Project (3GPP cellular network , by focusing on secure and energy efficient communications. New metrics that bind together the secure area in the Base Station (BS sectors, the afforded date-rate and the power spent by the BS to obtain it, are proposed that permit evaluation of the tradeoff between these aspects. The results show that these metrics are useful in identifying the optimum transmit power level for the BS, so that the maximum secure area can be obtained while minimizing the energy consumption.

  20. Secure Real-Time Monitoring and Management of Smart Distribution Grid using Shared Cellular Networks

    DEFF Research Database (Denmark)

    Nielsen, Jimmy Jessen; Ganem, Hervé; Jorguseski, Ljupco

    2017-01-01

    The electricity production and distribution is facing two major changes. First, the production is shifting from classical energy sources such as coal and nuclear power towards renewable resources such as solar and wind. Secondly, the consumption in the low voltage grid is expected to grow signifi......, where the smart grid ICT solutions are provided through shared cellular LTE networks.......The electricity production and distribution is facing two major changes. First, the production is shifting from classical energy sources such as coal and nuclear power towards renewable resources such as solar and wind. Secondly, the consumption in the low voltage grid is expected to grow...... significantly due to expected introduction of electrical vehicles. The first step towards more efficient operational capabilities is to introduce an observability of the distribution system and allow for lever- aging the flexibility of end connection points with manageable consumption, generation and storage...

  1. Cooperative beamforming for dual-hop amplify-and-forward multi-antenna relaying cellular networks

    KAUST Repository

    Xing, Chengwen

    2012-11-01

    In this paper, linear beamforming design for amplify-and-forward relaying cellular networks is considered, in which base station, relay station and mobile terminals are all equipped with multiple antennas. The design is based on minimum mean-square-error criterion, and both uplink and downlink scenarios are considered. It is found that the downlink and uplink beamforming design problems are in the same form, and iterative algorithms with the same structure can be used to solve the design problems. For the specific cases of fully loaded or overloaded uplink systems, a novel algorithm is derived and its relationships with several existing beamforming design algorithms for conventional MIMO or multiuser systems are revealed. Simulation results are presented to demonstrate the performance advantage of the proposed design algorithms. © 2012 Published by Elsevier B.V. All rights reserved.

  2. A novel root-index based prioritized random access scheme for 5G cellular networks

    Directory of Open Access Journals (Sweden)

    Taehoon Kim

    2015-12-01

    Full Text Available Cellular networks will play an important role in realizing the newly emerging Internet-of-Everything (IoE. One of the challenging issues is to support the quality of service (QoS during the access phase, while accommodating a massive number of machine nodes. In this paper, we show a new paradigm of multiple access priorities in random access (RA procedure and propose a novel root-index based prioritized random access (RIPRA scheme that implicitly embeds the access priority in the root index of the RA preambles. The performance evaluation shows that the proposed RIPRA scheme can successfully support differentiated performance for different access priority levels, even though there exist a massive number of machine nodes.

  3. Full Duplex Emulation via Spatial Separation of Half Duplex Nodes in a Planar Cellular Network

    DEFF Research Database (Denmark)

    Thomsen, Henning; Kim, Dong Min; Popovski, Petar;

    2016-01-01

    A Full Duplex Base Station (FD-BS) can be used to serve simultaneously two Half-Duplex (HD) Mobile Stations (MSs), one working in the uplink and one in the downlink, respectively. The same functionality can be realized by having two interconnected and spatially separated Half Duplex Base Stations...... (HD-BSs), which is a scheme termed CoMPflex (CoMP for In-Band Wireless Full Duplex). A FD-BS can be seen as a special case of CoMPflex with separation distance zero. In this paper we study the performance of CoMPflex in a two-dimensional cellular scenario using stochastic geometry and compare...... of communication reliability. Following the trend of wireless network densification, CoMPflex can be regarded as a method with a great potential to effectively use the dense HD deployments....

  4. Attractors and the attraction basins of discrete-time cellular neural networks

    Institute of Scientific and Technical Information of China (English)

    Ma Runnian; Xi Youmin

    2005-01-01

    The dynamic behavior of discrete-time cellular neural networks(DTCNN), which is strict with zero threshold value, is mainly studied in asynchronous mode and in synchronous mode. In general, a k-attractor of DTCNN is not a convergent point.But in this paper, it is proved that a k-attractor is a convergent point if the strict DTCNN satisfies some conditions. The attraction basin of the strict DTCNN is studied, one example is given to illustrate the previous conclusions to be wrong, and several results are presented. The obtained results on k-attractor and attraction basin not only correct the previous results, but also provide a theoretical foundation of performance analysis and new applications of the DTCNN.

  5. Modeling of trophospheric ozone concentrations using genetically trained multi-level cellular neural networks

    Science.gov (United States)

    Ozcan, H. Kurtulus; Bilgili, Erdem; Sahin, Ulku; Ucan, O. Nuri; Bayat, Cuma

    2007-09-01

    Tropospheric ozone concentrations, which are an important air pollutant, are modeled by the use of an artificial intelligence structure. Data obtained from air pollution measurement stations in the city of Istanbul are utilized in constituting the model. A supervised algorithm for the evaluation of ozone concentration using a genetically trained multi-level cellular neural network (ML-CNN) is introduced, developed, and applied to real data. A genetic algorithm is used in the optimization of CNN templates. The model results and the actual measurement results are compared and statistically evaluated. It is observed that seasonal changes in ozone concentrations are reflected effectively by the concentrations estimated by the multilevel-CNN model structure, with a correlation value of 0.57 ascertained between actual and model results. It is shown that the multilevel-CNN modeling technique is as satisfactory as other modeling techniques in associating the data in a complex medium in air pollution applications.

  6. Modeling of Trophospheric Ozone Concentrations Using Genetically Trained Multi-Level Cellular Neural Networks

    Institute of Scientific and Technical Information of China (English)

    H. Kurtulus OZCAN; Erdem BILGILI; Ulku SAHIN; O. Nuri UCAN; Cuma BAYAT

    2007-01-01

    Tropospheric ozone concentrations, which are an important air pollutant, are modeled by the use of an artificial intelligence structure. Data obtained from air pollution measurement stations in the city of Istanbul are utilized in constituting the model. A supervised algorithm for the evaluation of ozone concentration using a genetically trained multi-level cellular neural network (ML-CNN) is introduced, developed, and applied to real data. A genetic algorithm is used in the optimization of CNN templates. The model results and the actual measurement results are compared and statistically evaluated. It is observed that seasonal changes in ozone concentrations are reflected effectively by the concentrations estimated by the multilevel-CNN model structure, with a correlation value of 0.57 ascertained between actual and model results. It is shown that the multilevel-CNN modeling technique is as satisfactory as other modeling techniques in associating the data in a complex medium in air pollution applications.

  7. Global detection of live virtual machine migration based on cellular neural networks.

    Science.gov (United States)

    Xie, Kang; Yang, Yixian; Zhang, Ling; Jing, Maohua; Xin, Yang; Li, Zhongxian

    2014-01-01

    In order to meet the demands of operation monitoring of large scale, autoscaling, and heterogeneous virtual resources in the existing cloud computing, a new method of live virtual machine (VM) migration detection algorithm based on the cellular neural networks (CNNs), is presented. Through analyzing the detection process, the parameter relationship of CNN is mapped as an optimization problem, in which improved particle swarm optimization algorithm based on bubble sort is used to solve the problem. Experimental results demonstrate that the proposed method can display the VM migration processing intuitively. Compared with the best fit heuristic algorithm, this approach reduces the processing time, and emerging evidence has indicated that this new approach is affordable to parallelism and analog very large scale integration (VLSI) implementation allowing the VM migration detection to be performed better.

  8. Global Detection of Live Virtual Machine Migration Based on Cellular Neural Networks

    Directory of Open Access Journals (Sweden)

    Kang Xie

    2014-01-01

    Full Text Available In order to meet the demands of operation monitoring of large scale, autoscaling, and heterogeneous virtual resources in the existing cloud computing, a new method of live virtual machine (VM migration detection algorithm based on the cellular neural networks (CNNs, is presented. Through analyzing the detection process, the parameter relationship of CNN is mapped as an optimization problem, in which improved particle swarm optimization algorithm based on bubble sort is used to solve the problem. Experimental results demonstrate that the proposed method can display the VM migration processing intuitively. Compared with the best fit heuristic algorithm, this approach reduces the processing time, and emerging evidence has indicated that this new approach is affordable to parallelism and analog very large scale integration (VLSI implementation allowing the VM migration detection to be performed better.

  9. A novel memristive cellular neural network with time-variant templates

    Directory of Open Access Journals (Sweden)

    Xiaofang Hu

    2016-03-01

    Full Text Available A cellular neural network (CNN is a massively parallel analog array processor capable of solving various complex processing problems by using specific templates that characterize the synaptic connections. The hardware implementation and applications of CNN have attracted a great deal of attention. Recently, memristors with nanometer-scale and variable gradual conductance have been exploited to make compact and programmable electric synapses. This paper proposes and studies a novel memristive CNN (Mt-CNN with time-variant templates realized by memristor crossbar synaptic circuits. The template parameters are estimated analytically. The Mt-CNN provides a promising solution to hardware realization of real-time template updating processes, which can be used to effectively deal with various complicated problems of cascaded processing. Its effectiveness and advantages are demonstrated by practical examples of edge detection on noisy images.

  10. Two years of country-wide rainfall maps employing cellular communication networks

    Science.gov (United States)

    Uijlenhoet, Remko; Overeem, Aart; Leijnse, Hidde; Rios Gaona, Manuel Felipe

    2014-05-01

    Accurate rainfall observations with high spatial and temporal resolutions are needed for hydrological applications, agriculture, meteorology, and climate monitoring. However, the majority of the land surface of the earth lacks accurate rainfall information and the number of rain gauges is even severely declining in Europe, South-America, and Africa. This calls for alternative sources of rainfall information. Various studies have shown that microwave links from operational cellular telecommunication networks may be employed for rainfall monitoring. Such networks cover 20% of the land surface of the earth and have a high density, especially in urban areas. The basic principle of rainfall monitoring using microwave links is as follows. Rainfall attenuates the electromagnetic signals transmitted from one telephone tower to another. By measuring the received power at one end of a microwave link as a function of time, the path-integrated attenuation due to rainfall can be calculated. Previous studies have shown that average rainfall intensities over the length of a link can be derived from the path-integrated attenuation. This is particularly interesting for those countries where few surface rainfall observations are available. Here we present almost two years of country-wide rainfall maps employing cellular communication networks. A data set from a commercial microwave link network over the Netherlands is analyzed, containing data from an unprecedented number of links (~ 2000) covering the land surface of the Netherlands (35500 square kilometers). This data set almost completely covers the years 2011 and 2012. Fifteen-minute and daily rainfall maps (1 km spatial resolution) are derived from the microwave link data and compared to maps from a gauge-adjusted radar data set. The performance of the rainfall retrieval algorithm will be studied, particularly differences in time and space. Time series of air temperature and snow from automatic weather stations, operated by the

  11. Integrated service resource reservation using queueing networks theory

    DEFF Research Database (Denmark)

    Brewka, Lukasz Jerzy; Iversen, Villy Bæk; Kardaras, Georgios

    2014-01-01

    This study analyses multi-server multi-service queueing networks with service protection. To guarantee each service a certain quality-of-service and at the same time ensure high utilisation of servers, a minimum capacity is reserved each service. In addition, all services share the remaining non...

  12. Intragranular cellular segregation network structure strengthening 316L stainless steel prepared by selective laser melting

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, Yuan; Liu, Leifeng [Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, 10691 Stockholm (Sweden); Wikman, Stefan [Fusion for Energy, Torres Diagonal Litoral B3, Josep Pla 2, 08019 Barcelona (Spain); Cui, Daqing [Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, 10691 Stockholm (Sweden); Shen, Zhijian, E-mail: shen@mmk.su.se [Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, 10691 Stockholm (Sweden)

    2016-03-15

    A feasibility study was performed to fabricate ITER In-Vessel components by Selective Laser Melting (SLM) supported by Fusion for Energy (F4E). Almost fully dense 316L stainless steel (SS316L) components were prepared from gas-atomized powder and with optimized SLM processing parameters. Tensile tests and Charpy-V tests were carried out at 22 °C and 250 °C and the results showed that SLM SS316L fulfill the RCC-MR code. Microstructure characterization reveals the presence of hierarchical macro-, micro- and nano-structures in as-built samples that were very different from SS316L microstructures prepared by other established methods. The formation of a characteristic intragranular cellular segregation network microstructure appears to contribute to the increase of yield strength without losing ductility. Silicon oxide nano-inclusions were formed during the SLM process that generated a micro-hardness fluctuation in the building direction. The combined influence of a cellular microstructure and the nano-inclusions constraints the size of ductile dimples to nano-scale. The crack propagation is hindered by a pinning effect that improves the defect-tolerance of the SLM SS316L. This work proves that it was possible to manufacture SS316L with properties suitable for ITER First Wall panels. Further studies on irradiation properties of SLM SS316L and manufacturing of larger real-size components are needed. - Highlights: • The mechanical properties of SS316L made by selective laser melting fulfill RCC-MR. • SLM SS316L consists hierarchical structures of high heterogeneity. • Silicon rich oxide nano-inclusions are formed unexpectedly during SLM process. • Cellular structure and oxide nano-inclusions strengthen SLM SS316L.

  13. Intragranular cellular segregation network structure strengthening 316L stainless steel prepared by selective laser melting

    Science.gov (United States)

    Zhong, Yuan; Liu, Leifeng; Wikman, Stefan; Cui, Daqing; Shen, Zhijian

    2016-03-01

    A feasibility study was performed to fabricate ITER In-Vessel components by Selective Laser Melting (SLM) supported by Fusion for Energy (F4E). Almost fully dense 316L stainless steel (SS316L) components were prepared from gas-atomized powder and with optimized SLM processing parameters. Tensile tests and Charpy-V tests were carried out at 22 °C and 250 °C and the results showed that SLM SS316L fulfill the RCC-MR code. Microstructure characterization reveals the presence of hierarchical macro-, micro- and nano-structures in as-built samples that were very different from SS316L microstructures prepared by other established methods. The formation of a characteristic intragranular cellular segregation network microstructure appears to contribute to the increase of yield strength without losing ductility. Silicon oxide nano-inclusions were formed during the SLM process that generated a micro-hardness fluctuation in the building direction. The combined influence of a cellular microstructure and the nano-inclusions constraints the size of ductile dimples to nano-scale. The crack propagation is hindered by a pinning effect that improves the defect-tolerance of the SLM SS316L. This work proves that it was possible to manufacture SS316L with properties suitable for ITER First Wall panels. Further studies on irradiation properties of SLM SS316L and manufacturing of larger real-size components are needed.

  14. The Performance of Relay-Enhanced Cellular OFDMA-TDD Network for Mobile Broadband Wireless Services

    Directory of Open Access Journals (Sweden)

    Kyungmi Park

    2009-01-01

    Full Text Available A multihop relay (MR and repeater are useful means for improving system throughput and coverage in a cellular mobile packet access system, as the carrier-to-interference ratio can be improved when deploying them in a heavily shadowed region. In this paper, we report on our investigation of bandwidth efficiency and the associated service outage performance for different relay scenarios, using system level simulation for a cellular Orthogonal Frequency Division Multiple Access-Time Division Duplexing (OFDMA-TDD system. We have demonstrated that network throughput gain by typical optical repeaters, which have a simple amplify-and-forwarding capability in a full-duplexing mode, could be minimal in open space subject to cochannel interference from all repeaters in the neighboring cells. This is true, even though they are generally useful for warranting the outage performance with a multiple order of combining gain, especially in the destructive area, for example, basements or indoors with heavy wall attenuation, that naturally shields interference. Meanwhile, we show that multihop relays increase the average system capacity (almost doubling the system throughput by fully reusing the frequency in every relay station, while improving the per-user data rate in the cell edges or improving the outage performance in the heavily shadowed areas.

  15. Roadmap to cellular reprogramming--manipulating transcriptional networks with DNA, RNA, proteins and small molecules.

    Science.gov (United States)

    Wörsdörfer, P; Thier, M; Kadari, A; Edenhofer, F

    2013-06-01

    Recent reports demonstrate that the plasticity of mammalian somatic cells is much higher than previously assumed and that ectopic expression of transcription factors may have the potential to induce the conversion of any cell type into another. Fibroblast cells can be converted into embryonic stem cell-like cells, neural cells, cardiomyocytes, macrophage-like cells as well as blood progenitors. Additionally, the conversion of astrocytes into neurons or neural stem cells into monocytes has been demonstrated. Nowadays, in the era of systems biology, continuously growing holistic data sets are providing increasing insights into core transcriptional networks and cellular signaling pathways. This knowledge enables cell biologists to understand how cellular fate is determined and how it could be manipulated. As a consequence for biomedical applications, it might be soon possible to convert patient specific somatic cells directly into desired transplantable other cell types. The clinical value, however, of such reprogrammed cells is currently limited due to the invasiveness of methods applied to induce reprogramming factor activity. This review will focus on experimental strategies to ectopically induce cell fate modulators. We will emphasize those strategies that enable efficient and robust overexpression of transcription factors by minimal genetic alterations of the host genome. Furthermore, we will discuss procedures devoid of any genomic manipulation, such as the direct delivery of mRNA, proteins, or the use of small molecules. By this, we aim to give a comprehensive overview on state of the art techniques that harbor the potential to generate safe reprogrammed cells for clinical applications.

  16. Performance Analysis of Solar Photovoltaic Cells for Telecommunication Cellular Network in Remote Areas of Pakistan

    Directory of Open Access Journals (Sweden)

    Abdul Ghayur

    2016-10-01

    Full Text Available In this research design and implementation of solar photo voltaic cell is done for base transceiver system (BTS of telecom cellular networks in remote areas of Pakistan, to accomplish this task investigation is done regarding the present alternate power source of base transceiver system (BTS that is the generator sets used as a stand-by, prime and t-prime source. This research will examine that generator sets fuel consumption and maintenance cost is considerably high and the cellular company has to pay a lot to keep a site on air and to overcome the connectivity issues.To resolve these issues this research is aimed to implement solar technology on BTS, for this purpose exploration is done regarding BTS rectifier system and suggested to use power on distribution systems 16 (PODS 16, latest technology evolution (LTE based instead of the simple BTS rectifier, this new rectifier is intelligent and has redundant ways to overcome power issues as it has the capability to work directly on solar panel equipments and it requires DC supply. Other important factor is that solar panel recharge batteries for power backup and to keep the site on air during night time. Different cost comparison of solar and generator sets have been done by taking real data of different remote areas sites and in the end it is concluded that solar is the alternate costless, environmental friendly source of energy for BTS and can be implemented both for off-grid and on-grid systems.

  17. The challenges of M2M massive access in wireless cellular networks

    Directory of Open Access Journals (Sweden)

    Andrea Biral

    2015-02-01

    Full Text Available The next generation of communication systems, which is commonly referred to as 5G, is expected to support, besides the traditional voice and data services, new communication paradigms, such as Internet of Things (IoT and Machine-to-Machine (M2M services, which involve communication between Machine-Type Devices (MTDs in a fully automated fashion, thus, without or with minimal human intervention. Although the general requirements of 5G systems are progressively taking shape, the technological issues raised by such a vision are still partially unclear. Nonetheless, general consensus has been reached upon some specific challenges, such as the need for 5G wireless access networks to support massive access by MTDs, as a consequence of the proliferation of M2M services. In this paper, we describe the main challenges raised by the M2M vision, focusing in particular on the problems related to the support of massive MTD access in current cellular communication systems. Then we analyze the most common approaches proposed in the literature to enable the coexistence of conventional and M2M services in the current and next generation of cellular wireless systems. We finally conclude by pointing out the research challenges that require further investigation in order to provide full support to the M2M paradigm.

  18. Switched-based interference reduction scheme for open-access overlaid cellular networks

    KAUST Repository

    Radaydeh, Redha Mahmoud Mesleh

    2012-06-01

    Femtocells have been proposed to enhance the spatial coverage and system capacity of existing cellular networks. However, this technology may result in significant performance loss due to the increase in co-channel interference, particularly when coordination between access points is infeasible. This paper targets interference management in such overlaid networks. It is assumed that the femtocells employ the open-access strategy to reduce cross-tier interference, and can share resources concurrently. It is also assumed that each end user (EU) can access one channel at a time, and transfer limited feedback. To reduce the effect of co-tier interference in the absence of the desired EU channel state information (CSI) at the serving access point as well as coordination between active access points, a switched scheme based on the interference levels associated with available channels is proposed. Through the analysis, the scheme modes of operation in under-loaded and over-loaded channels are studied, from which the statistics of the resulting interference power are quantified. The impact of the proposed scheme on the received desired power is thoroughly discussed. In addition, the effect of the switching threshold on the achieved performance of the desired EU is investigated. The results clarify that the proposed scheme can improve the performance while reducing the number of examined channels and feedback load. © 2012 IEEE.

  19. AN EFFICIENT CELL SELECTION IN CELLULAR NETWORK WITH BETTER SCALABILITY AND RE-ROUTING

    Directory of Open Access Journals (Sweden)

    KARTHIKEYAN A.

    2014-11-01

    Full Text Available This paper mainly concentrate about Cell selection strategy and Re-Routing process in the Cellular Network. Cell selection is the process of deciding the cell to provide services to every mobile station. After the mobile user or mobile station make a call, then nearby base station will allocate space for that particular call through base station controller. The ultimate aim is to find a maximum-profit subset of clients that can be fully satisfied by All-or-Nothing Demand Maximization algorithm (AoNDM .Efficiency can be improved by Global Cell Selection mechanism. One of the important aspects of mobility management is mobility – ability to access service at anywhere, anyhow and anytime. The Edmonds–Karp algorithm is utilized to provide maximum flow from source to destination and deals the capacity of base station. For Re-Routing a predictive approach is used, where a Mcall is pre-established to potential new base stations by setting up a multicast tree with neighbouring base stations as leaf nodes. This Predictive approach reduces the latency caused by re-routing is in considerable level with strict time constraints. An extensive simulation study demonstrating the benefits of using our algorithms in high-loaded capacityconstrained of future 4G networks .Specifically, our algorithms obtain better usage of the network’s capacity, in comparison with the current cell selection algorithms and provide better results.

  20. An empirical Bayesian approach for model-based inference of cellular signaling networks

    Directory of Open Access Journals (Sweden)

    Klinke David J

    2009-11-01

    Full Text Available Abstract Background A common challenge in systems biology is to infer mechanistic descriptions of biological process given limited observations of a biological system. Mathematical models are frequently used to represent a belief about the causal relationships among proteins within a signaling network. Bayesian methods provide an attractive framework for inferring the validity of those beliefs in the context of the available data. However, efficient sampling of high-dimensional parameter space and appropriate convergence criteria provide barriers for implementing an empirical Bayesian approach. The objective of this study was to apply an Adaptive Markov chain Monte Carlo technique to a typical study of cellular signaling pathways. Results As an illustrative example, a kinetic model for the early signaling events associated with the epidermal growth factor (EGF signaling network was calibrated against dynamic measurements observed in primary rat hepatocytes. A convergence criterion, based upon the Gelman-Rubin potential scale reduction factor, was applied to the model predictions. The posterior distributions of the parameters exhibited complicated structure, including significant covariance between specific parameters and a broad range of variance among the parameters. The model predictions, in contrast, were narrowly distributed and were used to identify areas of agreement among a collection of experimental studies. Conclusion In summary, an empirical Bayesian approach was developed for inferring the confidence that one can place in a particular model that describes signal transduction mechanisms and for inferring inconsistencies in experimental measurements.

  1. Energy-Efficient Crowdsensing of Human Mobility and Signal Levels in Cellular Networks.

    Science.gov (United States)

    Foremski, Paweł; Gorawski, Michał; Grochla, Krzysztof; Polys, Konrad

    2015-09-02

    The paper presents a practical application of the crowdsensing idea to measure human mobility and signal coverage in cellular networks. Currently, virtually everyone is carrying a mobile phone, which may be used as a sensor to gather research data by measuring, e.g., human mobility and radio signal levels. However, many users are unwilling to participate in crowdsensing experiments. This work begins with the analysis of the barriers for engaging people in crowdsensing. A survey showed that people who agree to participate in crowdsensing expect a minimum impact on their battery lifetime and phone usage habits. To address these requirements, this paper proposes an application for measuring the location and signal strength data based on energy-efficient GPS tracking, which allows one to perform the measurements of human mobility and radio signal levels with minimum energy utilization and without any engagement of the user. The method described combines measurements from the accelerometer with effective management of the GPS to monitor the user mobility with the decrease in battery lifetime by approximately 20%. To show the applicability of the proposed platform, the sample results of signal level distribution and coverage maps gathered for an LTE network and representing human mobility are shown.

  2. Design of parallel microfluidic gradient-generating networks for studying cellular response to chemical stimuli

    Institute of Scientific and Technical Information of China (English)

    Lihui WANG; Dayu LIU; Bo WANG; Jie SUN; Lianhong LI

    2008-01-01

    A microfluidic chip featuring laminar flow-based parallel gradient-generating networks was designed and fabricated. The microchip contains 5 gradient genera-tors and 30 cell chambers where the resulting concentra-tion gradients of drugs are delivered to stimulate on-chip cultured cells. The microfluidics exploits the advantage of lab-on-a-chip technology by integrating the generation of drug concentration gradients and a series of cell opera-tions including seeding, culture, stimulation and staining into a chip. The microfluidic network was patterned on a glass wafer, which was further bonded to a PDMS film. A series of weir structures were fabricated on the cell culture reservoir to facilitate cell positioning and seeding. Cell injection and fluid delivery were controlled by a syringe pump. Steady parallel concentration gradients were gen-erated by flowing two fluids in each network. Over time observation shows that the microchip was suitable for cell seeding and culture. The microchip described above was applied in studying the role of reduced glutathione (GSH) in mediating chemotherapy sensitivity of MCF-7 cells. MCF-7 cells were treated with concentration gradients of As2O3 and N-acetyl cysteine (NAC) for GSH modu-lation, followed by exposure to adriamycin. GSH levels were down-regulated upon As203 treatment and up-regu-lated upon NAC treatment. Suppression of intracellular GSH by treatment with As2O3 has been shown to increase sensitivity to adriamycin. Conversely, elevation of intra-cellular GSH by treatment with NAC leads to increased drug resistance. The integrated microfluidic chip is able to perform multiparametric pharmacological profiling with easy operation, and thus holds great potential for extra-polation to the cell based high-content drug screening.

  3. EXISTENCE AND ATTRACTIVITY OF k-ALMOST AUTOMORPHIC SEQUENCE SOLUTION OF A MODEL OF CELLULAR NEURAL NETWORKS WITH DELAY

    Institute of Scientific and Technical Information of China (English)

    Syed ABBAS; Yonghui XIA

    2013-01-01

    In this paper we discuss the existence and global attractivity of k-almost automorphic sequence solution of a model of cellular neural networks.We consider the corresponding difference equation analogue of the model system using suitable discretization method and obtain certain conditions for the existence of solution.Almost automorphic function is a good generalization of almost periodic function.This is the first paper considering such solutions of the neural networks.

  4. Measurement and interpolation uncertainties in rainfall maps from cellular communication networks

    Science.gov (United States)

    Rios Gaona, M. F.; Overeem, A.; Leijnse, H.; Uijlenhoet, R.

    2015-08-01

    compared against quality-controlled gauge-adjusted radar rainfall fields (assumed to be the ground truth). Thus, we were able to not only identify and quantify the sources of uncertainty in such rainfall maps, but also test the actual and optimal performance of one commercial microwave network from one of the cellular providers in the Netherlands. Errors in microwave link measurements were found to be the source that contributes most to the overall uncertainty.

  5. Protein-protein interaction networks identify targets which rescue the MPP+ cellular model of Parkinson’s disease

    Science.gov (United States)

    Keane, Harriet; Ryan, Brent J.; Jackson, Brendan; Whitmore, Alan; Wade-Martins, Richard

    2015-11-01

    Neurodegenerative diseases are complex multifactorial disorders characterised by the interplay of many dysregulated physiological processes. As an exemplar, Parkinson’s disease (PD) involves multiple perturbed cellular functions, including mitochondrial dysfunction and autophagic dysregulation in preferentially-sensitive dopamine neurons, a selective pathophysiology recapitulated in vitro using the neurotoxin MPP+. Here we explore a network science approach for the selection of therapeutic protein targets in the cellular MPP+ model. We hypothesised that analysis of protein-protein interaction networks modelling MPP+ toxicity could identify proteins critical for mediating MPP+ toxicity. Analysis of protein-protein interaction networks constructed to model the interplay of mitochondrial dysfunction and autophagic dysregulation (key aspects of MPP+ toxicity) enabled us to identify four proteins predicted to be key for MPP+ toxicity (P62, GABARAP, GBRL1 and GBRL2). Combined, but not individual, knockdown of these proteins increased cellular susceptibility to MPP+ toxicity. Conversely, combined, but not individual, over-expression of the network targets provided rescue of MPP+ toxicity associated with the formation of autophagosome-like structures. We also found that modulation of two distinct proteins in the protein-protein interaction network was necessary and sufficient to mitigate neurotoxicity. Together, these findings validate our network science approach to multi-target identification in complex neurological diseases.

  6. Examining the limits of cellular adaptation bursting mechanisms in biologically-based excitatory networks of the hippocampus.

    Science.gov (United States)

    Ferguson, K A; Njap, F; Nicola, W; Skinner, F K; Campbell, S A

    2015-12-01

    Determining the biological details and mechanisms that are essential for the generation of population rhythms in the mammalian brain is a challenging problem. This problem cannot be addressed either by experimental or computational studies in isolation. Here we show that computational models that are carefully linked with experiment provide insight into this problem. Using the experimental context of a whole hippocampus preparation in vitro that spontaneously expresses theta frequency (3-12 Hz) population bursts in the CA1 region, we create excitatory network models to examine whether cellular adaptation bursting mechanisms could critically contribute to the generation of this rhythm. We use biologically-based cellular models of CA1 pyramidal cells and network sizes and connectivities that correspond to the experimental context. By expanding our mean field analyses to networks with heterogeneity and non all-to-all coupling, we allow closer correspondence with experiment, and use these analyses to greatly extend the range of parameter values that are explored. We find that our model excitatory networks can produce theta frequency population bursts in a robust fashion.Thus, even though our networks are limited by not including inhibition at present, our results indicate that cellular adaptation in pyramidal cells could be an important aspect for the occurrence of theta frequency population bursting in the hippocampus. These models serve as a starting framework for the inclusion of inhibitory cells and for the consideration of additional experimental features not captured in our present network models.

  7. DNA-damage response network at the crossroads of cell-cycle checkpoints,cellular senescence and apoptosis

    Institute of Scientific and Technical Information of China (English)

    SCHMITT Estelle; PAQUET Claudie; BEAUCHEMIN Myriam; BERTRAND Richard

    2007-01-01

    Tissue homeostasis requires a carefully-orchestrated balance between cell proliferation,cellular senescence and cell death.Cells proliferate through a cell cycle that is tightly regulated by cyclin-dependent kinase activities.Cellular senescence is a safeguard program limiting the proliferative competence of cells in living organisms.Apoptosis eliminates unwanted cells by the coordinated activity of gene products that regulate and effect cell death.The intimate link between the cell cycle,cellular senescence,apoptosis regulation,cancer development and tumor responses to cancer treatment has become eminently apparent.Extensive research on tumor suppressor genes,oncogenes,the cell cycle and apoptosis regulatory genes has revealed how the DNA damage-sensing and -signaling pathways,referred to as the DNA-damage response network,are tied to cell proliferation,cell-cycle arrest,cellular senescence and apoptosis.DNA-damage responses are complex,involving "sensor" proteins that sense the damage,and transmit signals to "transducer" proteins,which,in turn,convey the signals to numerous "effector" proteins implicated in specific cellular pathways,including DNA repair mechanisms,cell-cycle checkpoints,cellular senescence and apoptosis.The Bcl-2 family of proteins stands among the most crucial regulators of apoptosis and performs vital functions in deciding whether a cell will live or die after cancer chemotherapy and irradiation.In addition,several studies have now revealed that members of the Bcl-2 family also interface with the cell cycle,DNA repair/recombination and cellular senescence,effects that are generally distinct from their function in apoptosis.In this review,we report progress in understanding the molecular networks that regulate cell-cycle checkpoints,cellular senescence and apoptosis after DNA damage,and discuss the influence of some Bcl-2 family members on cell-cycle checkpoint regulation.

  8. Astrocytic gap junctional networks suppress cellular damage in an in vitro model of ischemia

    Energy Technology Data Exchange (ETDEWEB)

    Shinotsuka, Takanori; Yasui, Masato; Nuriya, Mutsuo, E-mail: mnuriya@z2.keio.jp

    2014-02-07

    Highlights: • Astrocytes exhibit characteristic changes in [Ca{sup 2+}]{sub i} under OGD. • Astrocytic [Ca{sup 2+}]{sub i} increase is synchronized with a neuronal anoxic depolarization. • Gap junctional couplings protect neurons as well as astrocytes during OGD. - Abstract: Astrocytes play pivotal roles in both the physiology and the pathophysiology of the brain. They communicate with each other via extracellular messengers as well as through gap junctions, which may exacerbate or protect against pathological processes in the brain. However, their roles during the acute phase of ischemia and the underlying cellular mechanisms remain largely unknown. To address this issue, we imaged changes in the intracellular calcium concentration ([Ca{sup 2+}]{sub i}) in astrocytes in mouse cortical slices under oxygen/glucose deprivation (OGD) condition using two-photon microscopy. Under OGD, astrocytes showed [Ca{sup 2+}]{sub i} oscillations followed by larger and sustained [Ca{sup 2+}]{sub i} increases. While the pharmacological blockades of astrocytic receptors for glutamate and ATP had no effect, the inhibitions of gap junctional intercellular coupling between astrocytes significantly advanced the onset of the sustained [Ca{sup 2+}]{sub i} increase after OGD exposure. Interestingly, the simultaneous recording of the neuronal membrane potential revealed that the onset of the sustained [Ca{sup 2+}]{sub i} increase in astrocytes was synchronized with the appearance of neuronal anoxic depolarization. Furthermore, the blockade of gap junctional coupling resulted in a concurrent faster appearance of neuronal depolarizations, which remain synchronized with the sustained [Ca{sup 2+}]{sub i} increase in astrocytes. These results indicate that astrocytes delay the appearance of the pathological responses of astrocytes and neurons through their gap junction-mediated intercellular network under OGD. Thus, astrocytic gap junctional networks provide protection against tissue damage

  9. Interference Management in Full-Duplex Cellular Networks with Partial Spectrum Overlap

    KAUST Repository

    Randrianantenaina, Itsikiantsoa

    2017-03-31

    Full-duplex (FD) communication is promoted to double the spectral efficiency when compared to the halfduplex (HD) counterpart. In the context of cellular networks, however, FD communication exacerbates the aggregate uplink and downlink interference, which diminishes the foreseen FD gains. This paper considers a flexible duplex system, denoted by -duplex (-D) system, wherein a fine-grained bandwidth control for each uplink/downlink channel pair in each base station (BS) is allowed, which also leads to partial spectrum overlap between the uplink and downlink channels. The paper addresses the resulting interference management problem by maximizing a network-wide rate-based utility function subject to uplink/downlink power constraints, so as to determine userto- BS association, user-to-channel scheduling, the UL and DL transmit powers, and the fraction of spectrum overlap between UL and DL for every user, under the assumption that the number of available channels and users are equal. The paper solves such a non-convex mixed-integer optimization problem in an iterative way by decoupling the problem into several subproblems. Particularly, the user-to-BS association problem is solved using a matching algorithm that is a generalization of the stable marriage problem. The scheduling problem is solved by iterative Hungarian algorithm. The power and spectrum overlap problem is solved by successive convex approximation. The proposed iterative strategy guarantees an efficient one-toone user to BS and channel assignment. It further provides optimized flexible duplexing and power allocation schemes for all transceivers. Simulations results show appreciable gains when comparing the proposed solution to different schemes from the literature.

  10. The Digital Age of Mobile Cellular Network in Germany and China: Policies, Technologies and Markets (Part Ⅱ)

    Institute of Scientific and Technical Information of China (English)

    Mingtao Shi

    2009-01-01

    The German Postal Reform Ⅰ in 1989 introduced competition in the mobile cellular market. German cellular operators, DeTeMobil, Mannesmann, E-Plus and VIAG Interkom, built D1-, D2-, El-and E2-Netze based on GSM standards made in Europe. China Unicom was created in 1994 and China Telecom was separated from MPT in 1995. China Telecom and China Unicom competed in a duopoly from the mid-1990s onwards and the cellular services provided by them also rely on GSM standards. China Telecom additionally deployed XLT technology (PHS) from the late 1990s onwards. While DeTeMobil and Mannesmann conquered approximately 80%-90% of the market throughout the 1990s and were the two dominant market players in Germany, China's cellular market was mainly controlled by China Mobile. In Germany, prices related to cellular technology continued the downwards trend as a major result of the process of deregulation, liberalisation and competition. In China, price wars had led to significant price reductions in the cellular market. Although network operators in both countries strived to deliver differentiated cellular services, the two national markets in the 1990s were visibly shaped by product homogeneity.

  11. Adiponectin fine-tuning of liver regeneration dynamics revealed through cellular network modeling.

    Science.gov (United States)

    Correnti, Jason M; Cook, Daniel; Aksamitiene, Edita; Swarup, Aditi; Ogunnaike, Babatunde; Vadigepalli, Rajanikanth; Hoek, Jan B

    2014-11-10

    Following partial hepatectomy, the liver initiates a regenerative program involving hepatocyte priming and replication driven by coordinated cytokine and growth factor actions. We investigated the mechanisms underlying Adiponectin's (Adn) regulation of liver regeneration through modulation of these mediators. Adn-/- mice showed delayed onset of hepatocyte replication, but accelerated cell cycle progression relative to wild-type mice, suggesting Adn has multiple effects fine-tuning the kinetics of liver regeneration. We developed a computational model describing the molecular and physiological kinetics of liver regeneration in Adn-/- mice. We employed this computational model to evaluate the underlying regulatory mechanisms. Our analysis predicted that Adn is required for an efficient early cytokine response to partial hepatectomy, but is inhibitory to later growth factor actions. Consistent with this prediction, Adn knockout reduced hepatocyte responses to IL-6 during the priming phase, but enhanced growth factor levels through peak hepatocyte replication. By contrast, supraphysiological concentrations of Adn resulting from rosiglitazone treatment suppressed regeneration by reducing growth factor levels during S phase, consistent with computational predictions. Together, these results revealed that Adn fine-tunes the progression of liver regeneration through dynamically modulating molecular mediator networks and cellular interactions within the liver. This article is protected by copyright. All rights reserved.

  12. Adiponectin fine-tuning of liver regeneration dynamics revealed through cellular network modelling.

    Science.gov (United States)

    Correnti, Jason M; Cook, Daniel; Aksamitiene, Edita; Swarup, Aditi; Ogunnaike, Babatunde; Vadigepalli, Rajanikanth; Hoek, Jan B

    2015-01-15

    Following partial hepatectomy, the liver initiates a regenerative programme involving hepatocyte priming and replication driven by the coordinated actions of cytokine and growth factors. We investigated the mechanisms underlying adiponectin's (Adn) regulation of liver regeneration through modulation of these mediators. Adn(-/-) mice showed delayed onset of hepatocyte replication, but accelerated cell cycle progression relative to wild-type mice, suggesting Adn has multiple effects fine-tuning the kinetics of liver regeneration. We developed a computational model describing the molecular and physiological kinetics of liver regeneration in Adn(-/-) mice. We employed this computational model to evaluate the underlying regulatory mechanisms. Our analysis predicted that Adn is required for an efficient early cytokine response to partial hepatectomy, but is inhibitory to later growth factor actions. Consistent with this prediction, Adn knockout reduced hepatocyte responses to interleukin-6 during the priming phase, but enhanced growth factor levels through peak hepatocyte replication. By contrast, supraphysiological concentrations of Adn resulting from rosiglitazone treatment suppressed regeneration by reducing growth factor levels during S phase, consistent with computational predictions. Together, these results revealed that Adn fine-tunes the progression of liver regeneration through dynamically modulating molecular mediator networks and cellular interactions within the liver.

  13. An Evaluation of Cellular Neural Networks for the Automatic Identification of Cephalometric Landmarks on Digital Images

    Directory of Open Access Journals (Sweden)

    Rosalia Leonardi

    2009-01-01

    Full Text Available Several efforts have been made to completely automate cephalometric analysis by automatic landmark search. However, accuracy obtained was worse than manual identification in every study. The analogue-to-digital conversion of X-ray has been claimed to be the main problem. Therefore the aim of this investigation was to evaluate the accuracy of the Cellular Neural Networks approach for automatic location of cephalometric landmarks on softcopy of direct digital cephalometric X-rays. Forty-one, direct-digital lateral cephalometric radiographs were obtained by a Siemens Orthophos DS Ceph and were used in this study and 10 landmarks (N, A Point, Ba, Po, Pt, B Point, Pg, PM, UIE, LIE were the object of automatic landmark identification. The mean errors and standard deviations from the best estimate of cephalometric points were calculated for each landmark. Differences in the mean errors of automatic and manual landmarking were compared with a 1-way analysis of variance. The analyses indicated that the differences were very small, and they were found at most within 0.59 mm. Furthermore, only few of these differences were statistically significant, but differences were so small to be in most instances clinically meaningless. Therefore the use of X-ray files with respect to scanned X-ray improved landmark accuracy of automatic detection. Investigations on softcopy of digital cephalometric X-rays, to search more landmarks in order to enable a complete automatic cephalometric analysis, are strongly encouraged.

  14. Opportunistic Interference Mitigation Achieves Optimal Degrees-of-Freedom in Cellular Networks

    CERN Document Server

    Jung, Bang Chul; Shin, Won-Yong

    2010-01-01

    We introduce an opportunistic interference mitigation (OIM) for cellular networks, where a user scheduling strategy is utilized in uplink $K$-cell environments with time-invariant channel coefficients and base stations (BSs) having $M$ receive antennas. In the OIM scheme, each BS opportunistically selects a set of users who generate the minimum interference to the other BSs. We consider two OIM protocols according to the number $S$ of simultaneously transmitting users per cell: an opportunistic interference nulling (OIN) and an opportunistic interference alignment (OIA). Then, their performance is analyzed in terms of degrees-of-freedom (DoFs). It is shown that $KM$ DoFs are achievable under the OIN protocol with $M$ selected users per cell, while the OIA scheme with $S$ selected users (smaller than $M$) achieves $KS$ DoFs. Assuming that $N$ denotes the total number of users in a cell, we also analyze the scaling condition between system parameters $K$, $M$, $N$, $S$, and the received signal-to-noise ratio su...

  15. A universal concept based on cellular neural networks for ultrafast and flexible solving of differential equations.

    Science.gov (United States)

    Chedjou, Jean Chamberlain; Kyamakya, Kyandoghere

    2015-04-01

    This paper develops and validates a comprehensive and universally applicable computational concept for solving nonlinear differential equations (NDEs) through a neurocomputing concept based on cellular neural networks (CNNs). High-precision, stability, convergence, and lowest-possible memory requirements are ensured by the CNN processor architecture. A significant challenge solved in this paper is that all these cited computing features are ensured in all system-states (regular or chaotic ones) and in all bifurcation conditions that may be experienced by NDEs.One particular quintessence of this paper is to develop and demonstrate a solver concept that shows and ensures that CNN processors (realized either in hardware or in software) are universal solvers of NDE models. The solving logic or algorithm of given NDEs (possible examples are: Duffing, Mathieu, Van der Pol, Jerk, Chua, Rössler, Lorenz, Burgers, and the transport equations) through a CNN processor system is provided by a set of templates that are computed by our comprehensive templates calculation technique that we call nonlinear adaptive optimization. This paper is therefore a significant contribution and represents a cutting-edge real-time computational engineering approach, especially while considering the various scientific and engineering applications of this ultrafast, energy-and-memory-efficient, and high-precise NDE solver concept. For illustration purposes, three NDE models are demonstratively solved, and related CNN templates are derived and used: the periodically excited Duffing equation, the Mathieu equation, and the transport equation.

  16. Flexible Design for α-Duplex Communications in Multi-Tier Cellular Networks

    KAUST Repository

    AlAmmouri, Ahmad

    2016-06-13

    Backward compatibility is an essential ingredient for the success of new technologies. In the context of inband full-duplex (FD) communication, FD base stations (BSs) should support half-duplex (HD) users’ equipment (UEs) without sacrificing the foreseen FD gains. This paper presents flexible and tractable modeling framework for multi-tier cellular networks with FD BSs and FD/HD UEs. The presented model is based on stochastic geometry and accounts for the intrinsic vulnerability of uplink transmissions. The results show that FD UEs are not necessarily required to harvest rate gains from FD BSs. In particular, the results show that adding FD UEs to FD BSs offers a maximum of 5% rate gain over FD BSs and HD UEs case if multi-user diversity is exploited, which is a marginal gain compared to the burden required to implement FD transceivers at the UEs’ side. To this end, we shed light on practical scenarios where HD UEs operation with FD BSs outperforms the operation when both the BSs and UEs are FD and we find a closed form expression for the critical value of the self-interference attenuation power required for the FD UEs to outperform HD UEs.

  17. Memristor-based cellular nonlinear/neural network: design, analysis, and applications.

    Science.gov (United States)

    Duan, Shukai; Hu, Xiaofang; Dong, Zhekang; Wang, Lidan; Mazumder, Pinaki

    2015-06-01

    Cellular nonlinear/neural network (CNN) has been recognized as a powerful massively parallel architecture capable of solving complex engineering problems by performing trillions of analog operations per second. The memristor was theoretically predicted in the late seventies, but it garnered nascent research interest due to the recent much-acclaimed discovery of nanocrossbar memories by engineers at the Hewlett-Packard Laboratory. The memristor is expected to be co-integrated with nanoscale CMOS technology to revolutionize conventional von Neumann as well as neuromorphic computing. In this paper, a compact CNN model based on memristors is presented along with its performance analysis and applications. In the new CNN design, the memristor bridge circuit acts as the synaptic circuit element and substitutes the complex multiplication circuit used in traditional CNN architectures. In addition, the negative differential resistance and nonlinear current-voltage characteristics of the memristor have been leveraged to replace the linear resistor in conventional CNNs. The proposed CNN design has several merits, for example, high density, nonvolatility, and programmability of synaptic weights. The proposed memristor-based CNN design operations for implementing several image processing functions are illustrated through simulation and contrasted with conventional CNNs. Monte-Carlo simulation has been used to demonstrate the behavior of the proposed CNN due to the variations in memristor synaptic weights.

  18. Low-complexity co-tier interference reduction scheme in open-access overlaid cellular networks

    KAUST Repository

    Radaydeh, Redha Mahmoud Mesleh

    2011-12-01

    This paper addresses the effect of co-tier interference on the performance of multiuser overlaid cellular networks that share the same available resources. It assumed that each macrocell contains a number of self-configurable and randomly located femtocells that employ the open-access control strategy to reduce the effect of cross-tier interference. It is also assumed that the desired user equipment (UE) can access only one of the available channels, maintains simple decoding circuitry with single receive antenna, and has limited knowledge of the instantaneous channel state information (CSI) due to resource limitation. To mitigate the effect of co-tier interference in the absence of the CSI of the desired UE, a low-complexity switched-based scheme for single channel selection based on the predicted interference levels associated with available channels is proposed for the case of over-loaded channels. Through the analysis, new general formulation for the statistics of the resulting instantaneous interference power and some performance measures are presented. The effect of the switching threshold on the efficiency and performance of the proposed scheme is studied. Numerical and simulation results to clarify the usefulness of the proposed scheme in reducing the impact of co-tier interference are also provided. © 2011 IEEE.

  19. Identifying disease feature genes based on cellular localized gene functional modules and regulation networks

    Institute of Scientific and Technical Information of China (English)

    ZHANG Min; ZHU Jing; GUO Zheng; LI Xia; YANG Da; WANG Lei; RAO Shaoqi

    2006-01-01

    Identifying disease-relevant genes and functional modules, based on gene expression profiles and gene functional knowledge, is of high importance for studying disease mechanisms and subtyping disease phenotypes. Using gene categories of biological process and cellular component in Gene Ontology, we propose an approach to selecting functional modules enriched with differentially expressed genes, and identifying the feature functional modules of high disease discriminating abilities. Using the differentially expressed genes in each feature module as the feature genes, we reveal the relevance of the modules to the studied diseases. Using three datasets for prostate cancer, gastric cancer, and leukemia, we have demonstrated that the proposed modular approach is of high power in identifying functionally integrated feature gene subsets that are highly relevant to the disease mechanisms. Our analysis has also shown that the critical disease-relevant genes might be better recognized from the gene regulation network, which is constructed using the characterized functional modules, giving important clues to the concerted mechanisms of the modules responding to complex disease states. In addition, the proposed approach to selecting the disease-relevant genes by jointly considering the gene functional knowledge suggests a new way for precisely classifying disease samples with clear biological interpretations, which is critical for the clinical diagnosis and the elucidation of the pathogenic basis of complex diseases.

  20. The potential of cellular network infrastructures for sudden rainfall monitoring in dry climate regions

    Science.gov (United States)

    David, N.; Alpert, P.; Messer, H.

    2013-09-01

    Monitoring of precipitation and in particular sudden rain, in rural dry climate regions, is a subject of great significance in several weather related processes such as soil erosion, flash flooding, triggering epidemics and more. The rainfall monitoring facilities in these regions and as a result precipitation data are, however, commonly, severely lacking. As was recently shown, cellular networks infrastructures supply high resolution precipitation measurements at ground level while often being situated in dry areas, covering large parts of these climatic zones. The potential found in these systems to provide early monitoring and essential precipitation information, directly from arid regions, based on standard measurements of commercial microwave links, is exemplified here over the Negev and the Southern Judean desert, South Israel. We present the results of two different rainfall events occurred in these regions. It is shown that the microwave system measured precipitation between at least 50 min (in case 1) and at least 1 h and 40 min (in case 2) before each of the sparse rain gauges. During each case, the radar system, located relatively far from the arid sites, provided measurements from heights of at least 1500 m and 2000 m above surface, respectively. A third case study demonstrates a relative advantage of microwave links to measure precipitation intensity with respect to the radar system, over an area of complex topography located in northeastern Israel, which is relatively far (~ 150 km) from the radar.

  1. Residual Separation of Magnetic Fields Using a Cellular Neural Network Approach

    Science.gov (United States)

    Albora, A. M.; Özmen, A.; Uçan, O. N.

    - In this paper, a Cellular Neural Network (CNN) has been applied to a magnetic regional/residual anomaly separation problem. CNN is an analog parallel computing paradigm defined in space and characterized by the locality of connections between processing neurons. The behavior of the CNN is defined by the template matrices A, B and the template vector I. We have optimized weight coefficients of these templates using Recurrent Perceptron Learning Algorithm (RPLA). The advantages of CNN as a real-time stochastic method are that it introduces little distortion to the shape of the original image and that it is not effected significantly by factors such as the overlap of power spectra of residual fields. The proposed method is tested using synthetic examples and the average depth of the buried objects has been estimated by power spectrum analysis. Next the CNN approach is applied to magnetic data over the Golalan chromite mine in Elazig which lies East of Turkey. This area is among the largest and richest chromite masses of the world. We compared the performance of CNN to classical derivative approaches.

  2. Reducing Call Blocks in Cellular Network with Non-Uniform Traffic Conditions

    Directory of Open Access Journals (Sweden)

    Sharma Abhijit

    2014-12-01

    Full Text Available In cellular networks, while the motivation behind all basic channel assignment strategies is the better utilization of the available frequency spectrum with the consequent reduction of the call blocking probability in each cell, very few of them deal with the problem of non-uniform traffic demand in different cells which may lead to a gross imbalance in the system performance. Mobile users in hot cells (the cells with heavy traffic loads may suffer from low throughput due to the load imbalance problem. In this paper, we propose a cost effective and simple load balancing scheme that can effectively reduce the overall call blocking. A common set of channels are determined dynamically which can be used simultaneously in all the cells. Cell tiers with different radii are used to cope with the interference introduced by using same set of channels simultaneously in all cells. The performance of the proposed scheme is presented in terms of call blocking probability and channel utilization. Simulation results show that the proposed scheme can reduce the call blocking significantly in highly congested cell.

  3. Multi-service highly sensitive rectifier for enhanced RF energy scavenging.

    Science.gov (United States)

    Shariati, Negin; Rowe, Wayne S T; Scott, James R; Ghorbani, Kamran

    2015-05-07

    Due to the growing implications of energy costs and carbon footprints, the need to adopt inexpensive, green energy harvesting strategies are of paramount importance for the long-term conservation of the environment and the global economy. To address this, the feasibility of harvesting low power density ambient RF energy simultaneously from multiple sources is examined. A high efficiency multi-resonant rectifier is proposed, which operates at two frequency bands (478-496 and 852-869 MHz) and exhibits favorable impedance matching over a broad input power range (-40 to -10 dBm). Simulation and experimental results of input reflection coefficient and rectified output power are in excellent agreement, demonstrating the usefulness of this innovative low-power rectification technique. Measurement results indicate an effective efficiency of 54.3%, and an output DC voltage of 772.8 mV is achieved for a multi-tone input power of -10 dBm. Furthermore, the measured output DC power from harvesting RF energy from multiple services concurrently exhibits a 3.14 and 7.24 fold increase over single frequency rectification at 490 and 860 MHz respectively. Therefore, the proposed multi-service highly sensitive rectifier is a promising technique for providing a sustainable energy source for low power applications in urban environments.

  4. Design and Performance Evaluation of Cooperative Retransmission Scheme for Reliable Multicast Services in Cellular Controlled P2P Networks

    DEFF Research Database (Denmark)

    Zhang, Qi; Fitzek, F.H.P.; Iversen, Villy Bæk

    2007-01-01

    communication architecture. It is referred to as cellular controlled peer-to- peer network, where the mobile devices communicate directly with each other to perform cooperative retransmissions using their short-range communication capabilities in addition to their cellular links. Based on the cooperative...... architecture a novel retransmission scheme is proposed exploiting the short-range retransmission in this paper. The state of the art, the non-cooperative error recovery schemes (e.g., ARQ, Layered FEC and Integrated FEC II) and the proposed scheme are compared with each other in terms of energy consumption...... to show the benefit of the newly introduced scheme....

  5. Prediction of the moderator temperature field in a heavy water reactor based on a cellular neural network

    Directory of Open Access Journals (Sweden)

    S.O. Starkov

    2017-06-01

    Full Text Available Reactors with heavy water coolants and moderators have been used extensively in today's power industry. Monitoring of the moderator condition plays an important role in ensuring normal operation of a power plant. A cellular neural network, the architecture of which has been adapted for hardware implementation, is proposed for use in a system for prediction of the heavy water moderator temperature. A reactor model composed in accordance with the CANDU Darlington heavy water reactor design was used to form the training sample collection and to control correct operation of the neural network structure. The sample components for the adjustment and configuration of the network topology include key parameters that characterize the energy generation process in the core. The paper considers the feasibility of the temperature prediction only for the calandria's central cross-section. To solve this problem, the cellular neural network architecture has been designed, and major parts of the digital computational element and methods for their implementation based on an FPLD have also been developed. The method is described for organizing an optical coupling between individual neural modules within the network, which enables not only the restructuring of the topology in the training process, but also the assignment of priorities for the propagation of the information signals of neurons depending on the activity in a situation analysis at the neural network structure inlet. Asynchronous activation of cells was used based on an oscillating fractal network, the basis for which was a modified ring oscillator. The efficiency of training the proposed architecture using stochastic diffusion search algorithms is evaluated. A comparative analysis of the model behavior and the results of the neural network operation have shown that the use of the neural network approach is effective in safety systems of power plants.

  6. FANTASTIC-5G: flexible air interface for scalable service delivery within wireless communication networks of the 5th generation

    DEFF Research Database (Denmark)

    Schaich, Frank; Sayrac, Berna; Elayoubi, Salaheddine

    2016-01-01

    5th generation mobile networks will have to cope with a high degree of heterogeneity in terms of services, mobility, number of devices and so on. Thus, diverse and often contradicting key performance indicators need to be supported, but having multiple radio access technologies for multi-service...... support below 6 GHz will be too costly. FANTASTIC-5G will develop a new multi-service air interface through a modular design. To allow the system to adapt to the anticipated heterogeneity, some properties need to be pursued, like simplicity, flexibility, scalability, versatility, efficiency and future...

  7. Design and simulation of cellular nonlinear networks using single-electron tunneling transistor technology

    Science.gov (United States)

    Gerousis, Costa P.

    It is currently predicted that semiconductor device scaling will end at the 22-nm device feature size (7 nm physical channel length) according to the International Technology Roadmap for Semiconductors. The main challenge is then to develop innovative technologies that will extend the scaling beyond roadmap projection. Any new technology must be well matched with complementary metal oxide semiconductor (CMOS) technology and scaleable beyond CMOS scaling projections and must provide low-power high-speed signal processing. Nanotechnology will become an appealing option for developing devices for integrated circuits with dimensions and performances well beyond roadmap predictions. Such devices, based on the controllable transfer of charge between dots or 'islands', can take advantage of the quantum mechanical effects, such as tunneling and energy quantization, which would normally occur at the nanometer scale. An outstanding challenge is in arranging such nanodevices in new architectures that can be integrated on a single chip. In particular, locally interconnected architectures are believed to be necessary to alleviate the problems associated with increasing interconnect length and complexity in ultra-dense circuits. The goal of this work is to investigate the use of nanoelectronic structures in cellular non-linear network (CNN) architectures for potential application in future high-density and low-power CMOS-nanodevice hybrid circuits. The operation of the single-electron tunneling (SET) transistor is first reviewed, followed by a discussion of simple CNN linear architectures using a SET inverter topology as the basis for the non-linear transfer characteristics for individual cells to be used in analog processing arrays for image-processing applications. The basic SET CNN cell acts as a summing node that is capacitively coupled to the inputs and outputs of nearest neighbor cells. Monte Carlo simulation results are used to show CNN-like behavior in attempting to

  8. Memristor standard cellular neural networks computing in the flux-charge domain.

    Science.gov (United States)

    Di Marco, Mauro; Forti, Mauro; Pancioni, Luca

    2017-09-01

    The paper introduces a class of memristor neural networks (NNs) that are characterized by the following salient features. (a) The processing of signals takes place in the flux-charge domain and is based on the time evolution of memristor charges. The processing result is given by the constant asymptotic values of charges that are stored in the memristors acting as non-volatile memories in steady state. (b) The dynamic equations describing the memristor NNs in the flux-charge domain are analogous to those describing, in the traditional voltage-current domain, the dynamics of a standard (S) cellular (C) NN, and are implemented by using a realistic model of memristors as that proposed by HP. This analogy makes it possible to use the bulk of results in the SCNN literature for designing memristor NNs to solve processing tasks in real time. Convergence of memristor NNs in the presence of multiple asymptotically stable equilibrium points is addressed and some applications to image processing tasks are presented to illustrate the real-time processing capabilities. Computing in the flux-charge domain is shown to have significant advantages with respect to computing in the voltage-current domain. One advantage is that, when a steady state is reached, currents, voltages and hence power in a memristor NN vanish, whereas memristors keep in memory the processing result. This is basically different from SCNNs for which currents, voltages and power do not vanish at a steady state, and batteries are needed to keep in memory the processing result. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Impedance matching network for high frequency ultrasonic transducer for cellular applications.

    Science.gov (United States)

    Kim, Min Gon; Yoon, Sangpil; Kim, Hyung Ham; Shung, K Kirk

    2016-02-01

    An approach for the design of an impedance matching network (IMN) for high frequency ultrasonic transducers with large apertures based on impedance analysis for cellular applications is presented in this paper. The main objectives were to maximize energy transmission from the excitation source to the ultrasonic transducers for cell manipulation and to achieve low input parameters for the safe operation of an ultrasonic transducer because the piezoelectric material in high frequency ultrasonic transducers is prone to breakage due to its being extremely thin. Two ultrasonic transducers, which were made of lithium niobate single crystal with the thickness of 15 μm, having apertures of 4.3 mm (fnumber=1.23) and 2.6mm (fnumber=0.75) were tested. L-type IMN was selected for high sensitivity and compact design of the ultrasonic transducers. The target center frequency was chosen as the frequency where the electrical admittance (|Y|) and phase angle (θz) from impedance analysis was maximal and zero, respectively. The reference center frequency and reference echo magnitude were selected as the center frequency and echo magnitude, measured by pulse-echo testing, of the ultrasonic transducer without IMN. Initial component values and topology of IMN were determined using the Smith chart, and pulse-echo testing was analyzed to verify the performance of the ultrasonic transducers with and without IMN. After several iterations between changing component values and topology of IMN, and pulse-echo measurement of the ultrasonic transducer with IMN, optimized component values and topology of IMN were chosen when the measured center frequency from pulse-echo testing was comparable to the target frequency, and the measured echo magnitude was at least 30% larger than the reference echo magnitude. Performance of an ultrasonic transducer with and without IMN was tested by observing a tangible dent on the surface of a plastic petridish and single cell response after an acoustic pulse was

  10. Implementation of a cellular neural network-based segmentation algorithm on the bio-inspired vision system

    Science.gov (United States)

    Karabiber, Fethullah; Grassi, Giuseppe; Vecchio, Pietro; Arik, Sabri; Yalcin, M. Erhan

    2011-01-01

    Based on the cellular neural network (CNN) paradigm, the bio-inspired (bi-i) cellular vision system is a computing platform consisting of state-of-the-art sensing, cellular sensing-processing and digital signal processing. This paper presents the implementation of a novel CNN-based segmentation algorithm onto the bi-i system. The experimental results, carried out for different benchmark video sequences, highlight the feasibility of the approach, which provides a frame rate of about 26 frame/sec. Comparisons with existing CNN-based methods show that, even though these methods are from two to six times faster than the proposed one, the conceived approach is more accurate and, consequently, represents a satisfying trade-off between real-time requirements and accuracy.

  11. Associative memories based on continuous-time cellular neural networks designed using space-invariant cloning templates.

    Science.gov (United States)

    Zeng, Zhigang; Wang, Jun

    2009-01-01

    Associative memories are brain-style devices designed to store a set of patterns as stable equilibria such that the stored patterns can be reliably retrieved with the initial probes containing sufficient information about the patterns. This paper presents a new design procedure for synthesizing associative memories based on continuous-time cellular neural networks with time delays characterized by input and output matrices obtained using two-dimensional space-invariant cloning templates. The design procedure enables hetero-associative or auto-associative memories to be synthesized by solving a set of linear inequalities with few design parameters and retrieval probes feeding from external inputs instead of initial states. The designed associative memories are robust in terms of design parameter selection. In addition, the hosting cellular neural networks are guaranteed to be globally exponentially stable. Simulation and experimental results of illustrative examples and Monte Carlo tests demonstrate the applicability and superiority of the methodology.

  12. Radio Capacity Estimation for Millimeter Wave 5G Cellular Networks Using Narrow Beamwidth Antennas at the Base Stations

    Directory of Open Access Journals (Sweden)

    AlMuthanna Turki Nassar

    2015-01-01

    Full Text Available This paper presents radio frequency (RF capacity estimation for millimeter wave (mm-wave based fifth-generation (5G cellular networks using field-level simulations. It is shown that, by reducing antenna beamwidth from 65° to 30°, we can enhance the capacity of mm-wave cellular networks roughly by 3.0 times at a distance of 220 m from the base station (BS. This enhancement is far much higher than the corresponding enhancement of 1.2 times observed for 900 MHz and 2.6 GHz microwave networks at the same distance from the BS. Thus the use of narrow beamwidth transmitting antennas has more pronounced benefits in mm-wave networks. Deployment trials performed on an LTE TDD site operating on 2.6 GHz show that 6-sector site with 27° antenna beamwidth enhances the quality of service (QoS roughly by 40% and more than doubles the overall BS throughput (while enhancing the per sector throughput 1.1 times on average compared to a 3-sector site using 65° antenna beamwidth. This agrees well with our capacity simulations. Since mm-wave 5G networks will use arbitrary number of beams, with beamwidth much less than 30°, the capacity enhancement expected in 5G system when using narrow beamwidth antennas would be much more than three times observed in our simulations.

  13. Geometric phase transition in the cellular network of the pancreatic islets may underlie the onset of type 1diabetes

    Science.gov (United States)

    Wang, Xujing

    Living systems are characterized by complexity in structure and emergent dynamic orders. In many aspects the onset of a chronic disease resembles phase transition in a dynamic system: quantitative changes accumulate largely unnoticed until a critical threshold is reached, which causes abrupt qualitative changes of the system. In this study we investigate this idea in a real example, the insulin-producing pancreatic islet β-cells and the onset of type 1 diabetes. Within each islet, the β-cells are electrically coupled to each other, and function as a network with synchronized actions. Using percolation theory we show how normal islet function is intrinsically linked to network connectivity, and the critical point where the islet cellular network loses site percolation, is consistent with laboratory and clinical observations of the threshold β-cell loss that causes islet functional failure. Numerical simulations confirm that the islet cellular network needs to be percolated for β-cells to synchronize. Furthermore, the interplay between site percolation and bond strength predicts the existence of a transient phase of islet functional recovery after disease onset and introduction of treatment, potentially explaining a long time mystery in the clinical study of type 1 diabetes: the honeymoon phenomenon. Based on these results, we hypothesized that the onset of T1D may be the result of a phase transition of the islet β-cell network. We further discuss the potential applications in identifying disease-driving factors, and the critical parameters that are predictive of disease onset.

  14. SERVICE-ORIENTED APPROACH FOR OPTIMAL ROUTING OF INFORMATION FLOWS IN MULTISERVICE NETWORKS

    Directory of Open Access Journals (Sweden)

    N. I. Listopad

    2015-01-01

    Full Text Available New approach for optimal routing of information flows is developed based on service-oriented architecture. To find the shortest path it’s require to take into account the QoS-parameters such as delay, jitter, bandwidth, lost of the packets and cost of telecommunication resources.

  15. Application of Local Activity Theory of Cellular Neural Network with Two Ports to the Coupled Lorenz-Cell Model

    Institute of Scientific and Technical Information of China (English)

    MIN LeQuan; YU Na

    2002-01-01

    Some criteria for the local activity theory in two-port cellular neural network cells with three local state variables are applied to a coupled Lorenz-cell model. The numerical simulation exhibited that emergence may exist if the selected cell parameters are nearby or on the edge of chaos domain. The local activity theory has provided a new tool of studying the complexity of high dimensional coupled nonlinear physical systems.

  16. Cellular Controlled Short-Range Communication for Cooperative P2P Networking

    DEFF Research Database (Denmark)

    Fitzek, Frank H. P.; Katz, Marcos; Zhang, Qi

    2009-01-01

    This article advocates a novel communication architecture and associated collaborative framework for future wireless communication systems. In contrast to the dominating cellular architecture and the upcoming peer-to-peer architecture, the new approach envisions a cellular controlled short-range ...

  17. SMTCI: Secure Multi-Trial Trust Evaluation and Cost- Effective Incentive Mechanism for Multi-Hop Cellular Networks

    Directory of Open Access Journals (Sweden)

    B.Sumathi

    2013-04-01

    Full Text Available In multi-hop cellular networks, finding an optimum and trusted route in the network through intermediate node is a major issue. At MCN, or the next-generation wireless networks, can significantly improve network performance and deployment and help implement many novel applications and services. However, when compared to wired and single-hop wireless networks, MCNs are highly vulnerable to serious security threats because packets may be relayed through integrated networks and autonomous devices. Our Proposed work has been focusing on developing secure trust based protocols for securing MCNs. Specifically, we are interested in securing route establishment and data transmission processes, establishing stable routes, and preserving users’ anonymity and location privacy. In this paperwe propose a multi-trial trust evaluation scheme, trusted node based ad hoc routing using trials to establish security accomplishes establishment of trusted networks in MANETs. We apply the same idea todevelop our proposed algorithm TBARA to rate neighbor nodes using hash values for identifying the misbehaving nodes. After the successful transmission of packets from source to destination, thedestination will send acknowledgement for the corresponding packet, upon receiving of acknowledgement incentive will be generated. It reduces the number of public-key cryptographic operations and protectagainst collusion attack.

  18. On the interference suppression capabilities of cognitive enabled femto cellular networks

    KAUST Repository

    Shakir, Muhammad

    2012-06-01

    Cognitive Radios are considered as a standard part of future Heterogeneous mobile network architecture. In this paper, we consider a two tier Heterogeneous network with multiple radio access technologies (RATS) namely; (i) the secondary network which comprises of cognitive enabled femto base stations which are referred to as cognitive-femto BS (CFBS) such that each of the BS are equipped with a single antenna and (ii) the macrocell network which is considered as a primary network. The effectiveness of the cognitive transmission is based on the efficient spectrum sensing algorithms which determine the availability of the spectrum holes. However, it is equally important for the cognitive network to minimize the cross-tier interference particularly during (i) the spectrum sensing and (ii) the cognitive transmission if spectrum is available. By exploiting the cooperation among the CFBS, the multiple CFBS can be considered as a single base station with multiple geographically dispersed antennas. In this context, we proposed a smart network where CFBS collaborates to reduce the cross-tier interference level by directing the main beam toward the desired femtocell mobile user and creating toward the cross-tier interference. The resultant network is referred to as Smart cognitive-femto network (SCFN) which requires the CFBS to be self-aware such that the CFBS are aware of their surroundings and adapt accordingly to maintain a reliable and efficient communication link. In order to determine the effectiveness of the proposed smart network, we study the interference rejection (or suppression) capabilities of the SCFN. It has been shown that the proposed smart network offers significant performance improvements in interference suppression and signal to interference ratio (SIR) and may be considered as a promising solution to the interference management problems in Heterogeneous network. © 2012 IEEE.

  19. Investigating meta-approaches for reconstructing gene networks in a mammalian cellular context.

    Directory of Open Access Journals (Sweden)

    Azree Nazri

    Full Text Available The output of state-of-the-art reverse-engineering methods for biological networks is often based on the fitting of a mathematical model to the data. Typically, different datasets do not give single consistent network predictions but rather an ensemble of inconsistent networks inferred under the same reverse-engineering method that are only consistent with the specific experimentally measured data. Here, we focus on an alternative approach for combining the information contained within such an ensemble of inconsistent gene networks called meta-analysis, to make more accurate predictions and to estimate the reliability of these predictions. We review two existing meta-analysis approaches; the Fisher transformation combined coefficient test (FTCCT and Fisher's inverse combined probability test (FICPT; and compare their performance with five well-known methods, ARACNe, Context Likelihood or Relatedness network (CLR, Maximum Relevance Minimum Redundancy (MRNET, Relevance Network (RN and Bayesian Network (BN. We conducted in-depth numerical ensemble simulations and demonstrated for biological expression data that the meta-analysis approaches consistently outperformed the best gene regulatory network inference (GRNI methods in the literature. Furthermore, the meta-analysis approaches have a low computational complexity. We conclude that the meta-analysis approaches are a powerful tool for integrating different datasets to give more accurate and reliable predictions for biological networks.

  20. Mechanical models of the cellular cytoskeletal network for the analysis of intracellular mechanical properties and force distributions: a review.

    Science.gov (United States)

    Chen, Ting-Jung; Wu, Chia-Ching; Su, Fong-Chin

    2012-12-01

    The cytoskeleton, which is the major mechanical component of cells, supports the cell body and regulates the cellular motility to assist the cell in performing its biological functions. Several cytoskeletal network models have been proposed to investigate the mechanical properties of cells. This review paper summarizes these models with a focus on the prestressed cable network, the semi-flexible chain network, the open-cell foam, the tensegrity, and the granular models. The components, material parameters, types of connection joints, tension conditions, and the advantages and disadvantages of each model are evaluated from a structural and biological point of view. The underlying mechanisms that are associated with the morphological changes of spreading cells are expected to be simulated using a cytoskeletal model; however, it is still paid less attention most likely due to the lack of a suitable cytoskeletal model that can accurately model the spreading process. In this review article, the established cytoskeletal models are hoped to provide useful information for the development of future cytoskeletal models with different degrees of cell attachment for the study of the mechanical mechanisms underlying the cellular behaviors in response to external stimulations.

  1. Toward a systems biology approach to investigate cellular networks in normal and malignant B cells.

    Science.gov (United States)

    Basso, K

    2009-07-01

    In recent years, we experienced an increasing development of new technologies that aim to comprehensively dissect the molecular genetics of cellular phenotypes. Pioneering studies have been performed on leukemia and lymphoma and then extended to many other types of malignancies. Genome-wide technologies allow taking snapshots of defined cellular context from an unbiased angle highlighting a complexity that we still struggle to fully interpret. The increasing availability of technologies to detect genetic, transcriptional and post-transcriptional characteristics of cellular systems needs to be associated with the development of computational tools to fully investigate these data in an integrated way. The evolution of different genome-wide technologies as well as data mining and integration tools will be discussed following studies performed on normal and malignant human mature B cells.

  2. Secrecy outage analysis of multi-user multi-eavesdropper cellular networks in the face of cochannel interference

    Directory of Open Access Journals (Sweden)

    Yuan Jiang

    2015-02-01

    Full Text Available This paper studies the physical-layer security of a multi-user multi-eavesdropper cellular network, which is composed of multiple users communicating with a base station while the eavesdroppers may intercept the communications from users to the base station (BS. The cellular network is a time-slotted system with simultaneously transmission, in each time slot, a single user is scheduled to transmit messages to BS while the remaining users opportunistically receive information. Considering multiple users available in the cellular network, we present three multi-user scheduling schemes, namely the round-robin scheduling scheme as well as the suboptimal and optimal user scheduling schemes to improve the security of communication (from users to BS against eavesdropping attacks. We only need to assume that the channel state information (CSI of the main link spanning from users to BS is known in the suboptimal scheduling. On the contrary, the optimal scheduling is designed by assuming that the CSI of the main link and wiretap link (spanning from users to the eavesdropper are available. We further carry out secrecy diversity analysis and show that the round-robin always achieves only one diversity order, whereas the suboptimal and optimal user scheduling schemes achieve the full diversity. In addition, numerical results illustrate that the optimal scheduling performs the best and the round-robin has the worst performance in terms of the secrecy outage probability. Last, as the number of users increases, the secrecy outage probabilities of the suboptimal and optimal scheduling schemes decrease significantly.

  3. Comparative analysis of Salmonella susceptibility and tolerance to the biocide chlorhexidine identifies a complex cellular defence network

    Directory of Open Access Journals (Sweden)

    Orla eCondell

    2014-08-01

    Full Text Available Chlorhexidine is one of the most widely used biocides in health and agricultural settings as well as in the modern food industry. It is a cationic biocide of the biguanide class. Details of its mechanism of action are largely unknown. The frequent use of chlorhexidine has been questioned recently, amidst concerns that an overuse of this compound may select for bacteria displaying an altered susceptibility to antimicrobials, including clinically important anti-bacterial agents.We generated a Salmonella enterica serovar Typhimurium isolate (ST24CHX that exhibited a high-level tolerant phenotype to chlorhexidine, following several rounds of in vitro selection, using sub-lethal concentrations of the biocide. This mutant showed altered suceptibility to a panel of clinically important antimicrobial compounds. Here we describe a genomic, transcriptomic, proteomic, and phenotypic analysis of the chlorhexidine tolerant S. Typhimurium compared with its isogenic sensitive progenitor. Results from this study describe a chlorhexidine defence network that functions in both the reference chlorhexidine sensitive isolate and the tolerant mutant. The defence network involved multiple cell targets including those associated with the synthesis and modification of the cell wall, the SOS response, virulence, and a shift in cellular metabolism towards anoxic pathways, some of which were regulated by CreB and Fur. In addition, results indicated that chlorhexidine tolerance was associated with more extensive modifications of the same cellular processes involved in this proposed network, as well as a divergent defence response involving the up-regulation of additional targets such as the flagellar apparatus and an altered cellular phosphate metabolism.These data show that sub-lethal concentrations of chlorhexidine induce distinct changes in exposed Salmonella, and our findings provide insights into the mechanisms of action and tolerance to this biocidal agent.

  4. Impact of network structure and cellular response on spike time correlations.

    Directory of Open Access Journals (Sweden)

    James Trousdale

    Full Text Available Novel experimental techniques reveal the simultaneous activity of larger and larger numbers of neurons. As a result there is increasing interest in the structure of cooperative--or correlated--activity in neural populations, and in the possible impact of such correlations on the neural code. A fundamental theoretical challenge is to understand how the architecture of network connectivity along with the dynamical properties of single cells shape the magnitude and timescale of correlations. We provide a general approach to this problem by extending prior techniques based on linear response theory. We consider networks of general integrate-and-fire cells with arbitrary architecture, and provide explicit expressions for the approximate cross-correlation between constituent cells. These correlations depend strongly on the operating point (input mean and variance of the neurons, even when connectivity is fixed. Moreover, the approximations admit an expansion in powers of the matrices that describe the network architecture. This expansion can be readily interpreted in terms of paths between different cells. We apply our results to large excitatory-inhibitory networks, and demonstrate first how precise balance--or lack thereof--between the strengths and timescales of excitatory and inhibitory synapses is reflected in the overall correlation structure of the network. We then derive explicit expressions for the average correlation structure in randomly connected networks. These expressions help to identify the important factors that shape coordinated neural activity in such networks.

  5. Mitigating Handoff Call Dropping in Wireless Cellular Networks: A Call Admission Control Technique

    Science.gov (United States)

    Ekpenyong, Moses Effiong; Udoh, Victoria Idia; Bassey, Udoma James

    2016-06-01

    Handoff management has been an important but challenging issue in the field of wireless communication. It seeks to maintain seamless connectivity of mobile users changing their points of attachment from one base station to another. This paper derives a call admission control model and establishes an optimal step-size coefficient (k) that regulates the admission probability of handoff calls. An operational CDMA network carrier was investigated through the analysis of empirical data collected over a period of 1 month, to verify the performance of the network. Our findings revealed that approximately 23 % of calls in the existing system were lost, while 40 % of the calls (on the average) were successfully admitted. A simulation of the proposed model was then carried out under ideal network conditions to study the relationship between the various network parameters and validate our claim. Simulation results showed that increasing the step-size coefficient degrades the network performance. Even at optimum step-size (k), the network could still be compromised in the presence of severe network crises, but our model was able to recover from these problems and still functions normally.

  6. Cell Identification based on Received Signal Strength Fingerprints: Concept and Application towards Energy Saving in Cellular Networks

    Directory of Open Access Journals (Sweden)

    Elke Roth-Mandutz

    2014-09-01

    Full Text Available The increasing deployment of small cells aimed at off-loading data traffic from macrocells in heterogeneous networks has resulted in a drastic increase in energy consumption in cellular networks. Energy consumption can be optimized in a selforganized way by adapting the number of active cells in response to the current traffic demand. In this paper we concentrate on the complex problem of how to identify small cells to be reactivated in situations where multiple cells are concurrently inactive. Solely based on the received signal strength, we present cell-specific patterns for the generation of unique cell fingerprints. The cell fingerprints of the deactivated cells are matched with measurements from a high data rate demanding mobile device to identify the most appropriate candidate. Our scheme results in a matching success rate of up to 100% to identify the best cell depending on the number of cells to be activated.

  7. Interference and Spectral Efficiency Analysis in Two-hop Cellular Network with Fixed Relays in FDD Mode

    Institute of Scientific and Technical Information of China (English)

    LI Ping; RONG Meng-tian; HUANG Lei; YU Dan

    2006-01-01

    This paper presented a scheme of two-hop cellular network with fixed relay nodes (FRN). Based on this scheme, co-channel interference and signal interference ratio(SIR) received by base station(BS) and FRN were analyzed. Both the theoretical analysis and simulation results show that the SIR can be improved significantly when relays are employed in the network. The higher spectral efficiency can be obtained due to the improved two-hop link quality through the use of adaptive modulation and coding (AMC). The antenna height of FRN and the cell radius of BS and that of FRN influence SIR received by BS and FRN and the system spectral efficiency greatly. The proper antenna height of FRN and cell radius of BS and that of FRN were also given to get the highest spectral efficiency.

  8. Protocol for Message Forwarding in Cellular and Mobile Opportunistic Wireless Network (Oppnets

    Directory of Open Access Journals (Sweden)

    Lokendra Singh Songare

    2013-09-01

    Full Text Available We describes hybrid approach for routing in opportunistic networks. In such networks there is no guarantee that a fully connected path between source and destination exists at any time, rendering traditional routing protocols unable to deliver messages between hosts. Thus, there is a need for a way to route through such networks. We propose hybrid approach which combines Prioritized Epidemic Routing and Probabilistic Routing. This approach prioritizes bundles based on costs to destination, source, and expiry time. Costs are derived from per-link “average availability” information that is disseminated in an epidemic manner.

  9. Investigating the Effects of Stress Interaction Using a Cellular-automaton Based Model in Fault Networks of Varying Complexity.

    Science.gov (United States)

    Hetherington, A. P.; Steacy, S.; McCloskey, J.

    2007-12-01

    Seismicity spatial and temporal patterns are strongly influenced by stress interaction between faults. However the effects of such interaction on earthquake statistics is not yet well understood. Computer models provide accurate, large and complete datasets to investigate this issue and also have the benefit of allowing direct comparison of seismicity behavior in time and space in networks, with and without fault interaction. We investigate the effect of such interaction on modeled real-world fault networks of varying complexity using a cellular-automata based model. Each 3-D fault within the fault network is modeled by a discrete cellular automaton. The cell size is 1 km square which allows for a minimum earthquake size of approximately Mw=4. The cell strength is distributed fractally across each fault and all cells are loaded by a remote tectonic stressing rate. When the stress on a cell exceeds its strength, the cell fails and stress is transferred to its nearest neighbors which may in turn cause them to break allowing the earthquake to grow. These stress transfer rules allow realistic stress concentrations to develop at the boundary of the rupture. If the extent of the rupture exceeds a user defined minimum length, and if interaction between faults is allowed, a boundary element method is used to calculate stress transfer to neighboring faults. Here we present results from four simulated fault networks based on active faults in the San Francisco Bay Area, California, the Northern Anatolian Fault, Turkey, Southern California, and the Marlborough Fault System, South Island, New Zealand. These are chosen for their varying level of fault complexity and we examine both interacting and non-interacting models in terms of their b-value and recurrence intervals for each region. Results will be compared and discussed.

  10. The challenges of M2M massive access in wireless cellular networks

    National Research Council Canada - National Science Library

    Biral, Andrea; Centenaro, Marco; Zanella, Andrea; Vangelista, Lorenzo; Zorzi, Michele

    2015-01-01

    .... Nonetheless, general consensus has been reached upon some specific challenges, such as the need for 5G wireless access networks to support massive access by MTDs, as a consequence of the proliferation of M2M services...

  11. A genetic network model of cellular responses to lithium treatment and cocaine abuse in bipolar disorder.

    Science.gov (United States)

    McEachin, Richard C; Chen, Haiming; Sartor, Maureen A; Saccone, Scott F; Keller, Benjamin J; Prossin, Alan R; Cavalcoli, James D; McInnis, Melvin G

    2010-11-19

    Lithium is an effective treatment for Bipolar Disorder (BD) and significantly reduces suicide risk, though the molecular basis of lithium's effectiveness is not well understood. We seek to improve our understanding of this effectiveness by posing hypotheses based on new experimental data as well as published data, testing these hypotheses in silico, and posing new hypotheses for validation in future studies. We initially hypothesized a gene-by-environment interaction where lithium, acting as an environmental influence, impacts signal transduction pathways leading to differential expression of genes important in the etiology of BD mania. Using microarray and rt-QPCR assays, we identified candidate genes that are differentially expressed with lithium treatment. We used a systems biology approach to identify interactions among these candidate genes and develop a network of genes that interact with the differentially expressed candidates. Notably, we also identified cocaine as having a potential influence on the network, consistent with the observed high rate of comorbidity for BD and cocaine abuse. The resulting network represents a novel hypothesis on how multiple genetic influences on bipolar disorder are impacted by both lithium treatment and cocaine use. Testing this network for association with BD and related phenotypes, we find that it is significantly over-represented for genes that participate in signal transduction, consistent with our hypothesized-gene-by environment interaction. In addition, it models related pharmacogenomic, psychiatric, and chemical dependence phenotypes. We offer a network model of gene-by-environment interaction associated with lithium's effectiveness in treating BD mania, as well as the observed high rate of comorbidity of BD and cocaine abuse. We identified drug targets within this network that represent immediate candidates for therapeutic drug testing. Posing novel hypotheses for validation in future work, we prioritized SNPs near

  12. The dynamic and geometric phase transition in the cellular network of pancreatic islet

    Science.gov (United States)

    Wang, Xujing

    2013-03-01

    The pancreatic islet is a micro-organ that contains several thousands of endocrine cells, majority of which being the insulin releasing β - cells . - cellsareexcitablecells , andarecoupledtoeachother through gap junctional channels. Here, using percolation theory, we investigate the role of network structure in determining the dynamics of the β-cell network. We show that the β-cell synchronization depends on network connectivity. More specifically, as the site occupancy is reducing, initially the β-cell synchronization is barely affected, until it reaches around a critical value, where the synchronization exhibit a sudden rapid decline, followed by an slow exponential tail. This critical value coincides with the critical site open probability for percolation transition. The dependence over bond strength is similar, exhibiting critical-behavior like dependence around a certain value of bond strength. These results suggest that the β-cell network undergoes a dynamic phase transition when the network is percolated. We further apply the findings to study diabetes. During the development of diabetes, the β - cellnetworkconnectivitydecreases . Siteoccupancyreducesfromthe reducing β-cell mass, and the bond strength is increasingly impaired from β-cell stress and chronic hyperglycemia. We demonstrate that the network dynamics around the percolation transition explain the disease dynamics around onset, including a long time mystery in diabetes, the honeymoon phenomenon.

  13. Unifying View on Min-Max Fairness, Max-Min Fairness, and Utility Optimization in Cellular Networks

    Directory of Open Access Journals (Sweden)

    Stanczak Slawomir

    2007-01-01

    Full Text Available We are concerned with the control of quality of service (QoS in wireless cellular networks utilizing linear receivers. We investigate the issues of fairness and total performance, which are measured by a utility function in the form of a weighted sum of link QoS. We disprove the common conjecture on incompatibility of min-max fairness and utility optimality by characterizing network classes in which both goals can be accomplished concurrently. We characterize power and weight allocations achieving min-max fairness and utility optimality and show that they correspond to saddle points of the utility function. Next, we address the problem of the difference between min-max fairness and max-min fairness. We show that in general there is a (fairness gap between the performance achieved under min-max fairness and under max-min fairness. We characterize the network class for which both performance values coincide. Finally, we characterize the corresponding network subclass, in which both min-max fairness and max-min fairness are achievable by the same power allocation.

  14. Discrimination of liver cancer in cellular level based on backscatter micro-spectrum with PCA algorithm and BP neural network

    Science.gov (United States)

    Yang, Jing; Wang, Cheng; Cai, Gan; Dong, Xiaona

    2016-10-01

    The incidence and mortality rate of the primary liver cancer are very high and its postoperative metastasis and recurrence have become important factors to the prognosis of patients. Circulating tumor cells (CTC), as a new tumor marker, play important roles in the early diagnosis and individualized treatment. This paper presents an effective method to distinguish liver cancer based on the cellular scattering spectrum, which is a non-fluorescence technique based on the fiber confocal microscopic spectrometer. Combining the principal component analysis (PCA) with back propagation (BP) neural network were utilized to establish an automatic recognition model for backscatter spectrum of the liver cancer cells from blood cell. PCA was applied to reduce the dimension of the scattering spectral data which obtained by the fiber confocal microscopic spectrometer. After dimensionality reduction by PCA, a neural network pattern recognition model with 2 input layer nodes, 11 hidden layer nodes, 3 output nodes was established. We trained the network with 66 samples and also tested it. Results showed that the recognition rate of the three types of cells is more than 90%, the relative standard deviation is only 2.36%. The experimental results showed that the fiber confocal microscopic spectrometer combining with the algorithm of PCA and BP neural network can automatically identify the liver cancer cell from the blood cells. This will provide a better tool for investigating the metastasis of liver cancers in vivo, the biology metabolic characteristics of liver cancers and drug transportation. Additionally, it is obviously referential in practical application.

  15. Beta Cell Formation in vivo Through Cellular Networking, Integration and Processing (CNIP) in Wild Type Adult Mice.

    Science.gov (United States)

    Doiron, Bruno; Hu, Wenchao; DeFronzo, Ralph A

    2016-01-01

    Insulin replacement therapy is essential in type 1 diabetic individuals and is required in ~40- 50% of type 2 diabetics during their lifetime. Prior attempts at beta cell regeneration have relied upon pancreatic injury to induce beta cell proliferation, dedifferentiation and activation of the embryonic pathway, or stem cell replacement. We report an alternative method to transform adult non-stem (somatic) cells into pancreatic beta cells. The Cellular Networking, Integration and Processing (CNIP) approach targets cellular mechanisms involved in pancreatic function in the organ's adult state and utilizes a synergistic mechanism that integrates three important levels of cellular regulation to induce beta cell formation: (i) glucose metabolism, (ii) membrane receptor function, and (iii) gene transcription. The aim of the present study was to induce pancreatic beta cell formation in vivo in adult animals without stem cells and without dedifferentiating cells to recapitulate the embryonic pathway as previously published (1-3). Our results employing CNIP demonstrate that: (i) insulin secreting cells can be generated in adult pancreatic tissue in vivo and circumvent the problem of generating endocrine (glucagon and somatostatin) cells that exert deleterious effects on glucose homeostasis, and (ii) longterm normalization of glucose tolerance and insulin secretion can be achieved in a wild type diabetic mouse model. The CNIP cocktail has the potential to be used as a preventative or therapeutic treatment or cure for both type 1 and type 2 diabetes.

  16. Design and Evaluation of IP Header Compression for Cellular-Controlled P2P Networks

    DEFF Research Database (Denmark)

    Madsen, T.K.; Zhang, Qi; Fitzek, F.H.P.

    2007-01-01

    In this paper we advocate to exploit terminal cooperation to stabilize IP communication using header compression. The terminal cooperation is based on direct communication between terminals using short range communication and simultaneously being connected to the cellular service access point....... The short range link is than used to provide first aid information to heal the decompressor state of the neighboring node in case of a packet loss on the cellular link. IP header compression schemes are used to increase the spectral and power efficiency loosing robustness of the communication compared...... to the uncompressed version. By introducing the terminal cooperation supporting header compression the robustness is increased. Within this article we will show that header compression should be applied to reduce the energy consumption of the terminals and moreover the header compression should be supported...

  17. Robust Template Decomposition without Weight Restriction for Cellular Neural Networks Implementing Arbitrary Boolean Functions Using Support Vector Classifiers

    Directory of Open Access Journals (Sweden)

    Yih-Lon Lin

    2013-01-01

    Full Text Available If the given Boolean function is linearly separable, a robust uncoupled cellular neural network can be designed as a maximal margin classifier. On the other hand, if the given Boolean function is linearly separable but has a small geometric margin or it is not linearly separable, a popular approach is to find a sequence of robust uncoupled cellular neural networks implementing the given Boolean function. In the past research works using this approach, the control template parameters and thresholds are restricted to assume only a given finite set of integers, and this is certainly unnecessary for the template design. In this study, we try to remove this restriction. Minterm- and maxterm-based decomposition algorithms utilizing the soft margin and maximal margin support vector classifiers are proposed to design a sequence of robust templates implementing an arbitrary Boolean function. Several illustrative examples are simulated to demonstrate the efficiency of the proposed method by comparing our results with those produced by other decomposition methods with restricted weights.

  18. Coverage extension and balancing the transmitted power of the moving relay node at LTE-A cellular network.

    Science.gov (United States)

    Aldhaibani, Jaafar A; Yahya, Abid; Ahmad, R Badlishah

    2014-01-01

    The poor capacity at cell boundaries is not enough to meet the growing demand and stringent design which required high capacity and throughput irrespective of user's location in the cellular network. In this paper, we propose new schemes for an optimum fixed relay node (RN) placement in LTE-A cellular network to enhance throughput and coverage extension at cell edge region. The proposed approach mitigates interferences between all nodes and ensures optimum utilization with the optimization of transmitted power. Moreover, we proposed a new algorithm to balance the transmitted power of moving relay node (MR) over cell size and providing required SNR and throughput at the users inside vehicle along with reducing the transmitted power consumption by MR. The numerical analysis along with the simulation results indicates that an improvement in capacity for users is 40% increment at downlink transmission from cell capacity. Furthermore, the results revealed that there is saving nearly 75% from transmitted power in MR after using proposed balancing algorithm. ATDI simulator was used to verify the numerical results, which deals with real digital cartographic and standard formats for terrain.

  19. Reconstruction of cellular signal transduction networks using perturbation assays and linear programming.

    Science.gov (United States)

    Knapp, Bettina; Kaderali, Lars

    2013-01-01

    Perturbation experiments for example using RNA interference (RNAi) offer an attractive way to elucidate gene function in a high throughput fashion. The placement of hit genes in their functional context and the inference of underlying networks from such data, however, are challenging tasks. One of the problems in network inference is the exponential number of possible network topologies for a given number of genes. Here, we introduce a novel mathematical approach to address this question. We formulate network inference as a linear optimization problem, which can be solved efficiently even for large-scale systems. We use simulated data to evaluate our approach, and show improved performance in particular on larger networks over state-of-the art methods. We achieve increased sensitivity and specificity, as well as a significant reduction in computing time. Furthermore, we show superior performance on noisy data. We then apply our approach to study the intracellular signaling of human primary nave CD4(+) T-cells, as well as ErbB signaling in trastuzumab resistant breast cancer cells. In both cases, our approach recovers known interactions and points to additional relevant processes. In ErbB signaling, our results predict an important role of negative and positive feedback in controlling the cell cycle progression.

  20. Optical networking standards a comprehensive guide for professionals

    CERN Document Server

    2006-01-01

    Optical Networking Standards: A Comprehensive Guide for Professionals provides a single source reference of over a hundred standards and industry technical specifications for optical networks at all levels: from components to networking systems through global networks, as well as coverage of networks management and services. This book focuses on the recently approved, adopted and implemented standards that have fueled the development of versatile switches, routers and multi-service provisioning platforms. These networking elements have enabled the service-providers world-wide to offer flexible yet customized bundled-services based on IP, MPLS and Carrier-Grade Ethernet.

  1. An ANN Based Call Handoff Management Scheme for Mobile Cellular Network

    Directory of Open Access Journals (Sweden)

    P. P. Bhattacharya

    2013-12-01

    Full Text Available Handoff decisions are usually signal strength based because of simplicity and effectiveness. Apart fro m the conventional techniques, such as threshold and hyst eresis based schemes, recently many artificial intelligent techniques such as Fuzzy Logic, Artific ial Neural Network (ANN etc. are also used for tak ing handoff decision. In this paper, an Artificial Neur al Network based handoff algorithm is proposed and it’s performance is studied. We have used ANNhere for ta king fast and accurate handoff decision. In our proposed handoff algorithm, Backpropagation Neural Network model is used.The advantages of Backpropagation method are its simplicity and reaso nable speed. The algorithm is designed, tested and found to give optimum results.

  2. iGPCR-drug: a web server for predicting interaction between GPCRs and drugs in cellular networking.

    Directory of Open Access Journals (Sweden)

    Xuan Xiao

    Full Text Available Involved in many diseases such as cancer, diabetes, neurodegenerative, inflammatory and respiratory disorders, G-protein-coupled receptors (GPCRs are among the most frequent targets of therapeutic drugs. It is time-consuming and expensive to determine whether a drug and a GPCR are to interact with each other in a cellular network purely by means of experimental techniques. Although some computational methods were developed in this regard based on the knowledge of the 3D (dimensional structure of protein, unfortunately their usage is quite limited because the 3D structures for most GPCRs are still unknown. To overcome the situation, a sequence-based classifier, called "iGPCR-drug", was developed to predict the interactions between GPCRs and drugs in cellular networking. In the predictor, the drug compound is formulated by a 2D (dimensional fingerprint via a 256D vector, GPCR by the PseAAC (pseudo amino acid composition generated with the grey model theory, and the prediction engine is operated by the fuzzy K-nearest neighbour algorithm. Moreover, a user-friendly web-server for iGPCR-drug was established at http://www.jci-bioinfo.cn/iGPCR-Drug/. For the convenience of most experimental scientists, a step-by-step guide is provided on how to use the web-server to get the desired results without the need to follow the complicated math equations presented in this paper just for its integrity. The overall success rate achieved by iGPCR-drug via the jackknife test was 85.5%, which is remarkably higher than the rate by the existing peer method developed in 2010 although no web server was ever established for it. It is anticipated that iGPCR-Drug may become a useful high throughput tool for both basic research and drug development, and that the approach presented here can also be extended to study other drug - target interaction networks.

  3. Rainfall measurements from cellular networks microwave links : an alternative ground reference for satellite validation and hydrology in Africa .

    Science.gov (United States)

    Gosset, Marielle; cazenave, frederic; Zougmore, françois; Doumounia, Ali; kacou, Modeste

    2015-04-01

    In many part of the Tropics the ground based gauge networks are sparse, often degrading and accessing this data for monitoring rainfall or for validating satellite products is sometime difficult. Here, an alternative rainfall measuring technique is proposed and tested in West Africa. It is based on using commercial microwave links from cellular telephone networks to detect and quantify rainfall. Rainfall monitoring based on commercial terrestrial microwave links has been tested for the first time in Burkina Faso, in Sahel. The rainfall regime is characterized by intense rainfall intensities brought by mesoscale Convective systems (MCS), generated by deep organized convection. The region is subjected to drought as well as dramatic floods associated with the intense rainfall provided by a few MCSs. The hydrometeorological risk is increasing and need to be monitored. In collaboration with the national cellular phone operator, Telecel Faso, the attenuation on 29 km long microwave links operating at 7 GHz was monitored at 1s time rate for the monsoon season 2012. The time series of attenuation is transformed into rain rates and compared with rain gauge data. The method is successful in quantifying rainfall: 95% of the rainy days are detected. The correlation with the daily raingauge series is 0.8 and the season bias is 5%. The correlation at the 5 min time step within each event is also high. We will present the quantitative results, discuss the uncertainties and compare the time series and the 2D maps with those derived from a polarimetric radar. The results demonstrate the potential interest of exploiting national and regional wireless telecommunication networks to provide rainfall maps for various applications : urban hydrology, agro-hydrological risk monitoring, satellite validation and development of combined rainfall products. We will also present the outcome of the first international Rain Cell Africa workshop held in Ouagadougou early 2015.

  4. The Data Age of Mobile Cellular Network in Germany and China: Policies, Technologies and Markets (Part Ⅱ)

    Institute of Scientific and Technical Information of China (English)

    Shi Mingtao

    2009-01-01

    The UMTS auction in 2000 brought approximately 100 billion DM (Deutsche Mark) for the German National Treasury. T-Mobile (D1-Netz), Vodafone (D2-Netz), E-Plus (E1-Netz) and 02 (E2-Netz) have gradually evolved from GSM to full-fledged UMTS operators over the past years. The conglomerate of China Telecom was split twice. China acceded to WTO and promulgated the FITE Provisions. MIIT (Ministry of Industry and Information Technology) became the regulator and China Netcom was incorporated into China Unicorn in 2008. Most recently the layout of 3G future has been reconfirmed by MIIT. Voice service has remained the main source of income in both countries and operators have continued to focus on voice quality and network availability in their respective 2G networks. Because value-added and higher-speed data applications have been gaining market attention, 2.5G and 3G infrastructure has increasingly become the focal network strategy for the operators since the beginning of the new century. Germany has rolled out WCDMA/UMTS services on a large scale in the consumer market, while China has adopted all three 3G standards (TD-SCDMA, WCDMA/UMTS, CDMA2000), which shall gradually capture a wider 3G subscriber base. The summary shows that the development of the cellular technology and market in Germany and China can be discussed in three distinct historical periods. The conclusion suggests that the case of the cellular technology appears to be consistent with and applicable to a number of arguments widely disputed in economics and management related to technology and innovation, such as dominant design, technology waves/ S-Curve, disruptive technologies, Technology Adoption Life Cycle.

  5. Best Signal Quality in Cellular Networks: Asymptotic Properties and Applications to Mobility Management in Small Cell Networks

    Directory of Open Access Journals (Sweden)

    Baccelli François

    2010-01-01

    Full Text Available The quickly increasing data traffic and the user demand for a full coverage of mobile services anywhere and anytime are leading mobile networking into a future of small cell networks. However, due to the high-density and randomness of small cell networks, there are several technical challenges. In this paper, we investigate two critical issues: best signal quality and mobility management. Under the assumptions that base stations are uniformly distributed in a ring-shaped region and that shadowings are lognormal, independent, and identically distributed, we prove that when the number of sites in the ring tends to infinity, then (i the maximum signal strength received at the center of the ring tends in distribution to a Gumbel distribution when properly renormalized, and (ii it is asymptotically independent of the interference. Using these properties, we derive the distribution of the best signal quality. Furthermore, an optimized random cell scanning scheme is proposed, based on the evaluation of the optimal number of sites to be scanned for maximizing the user data throughput.

  6. From Cellular Attractor Selection to Adaptive Signal Control for Traffic Networks.

    Science.gov (United States)

    Tian, Daxin; Zhou, Jianshan; Sheng, Zhengguo; Wang, Yunpeng; Ma, Jianming

    2016-03-14

    The management of varying traffic flows essentially depends on signal controls at intersections. However, design an optimal control that considers the dynamic nature of a traffic network and coordinates all intersections simultaneously in a centralized manner is computationally challenging. Inspired by the stable gene expressions of Escherichia coli in response to environmental changes, we explore the robustness and adaptability performance of signalized intersections by incorporating a biological mechanism in their control policies, specifically, the evolution of each intersection is induced by the dynamics governing an adaptive attractor selection in cells. We employ a mathematical model to capture such biological attractor selection and derive a generic, adaptive and distributed control algorithm which is capable of dynamically adapting signal operations for the entire dynamical traffic network. We show that the proposed scheme based on attractor selection can not only promote the balance of traffic loads on each link of the network but also allows the global network to accommodate dynamical traffic demands. Our work demonstrates the potential of bio-inspired intelligence emerging from cells and provides a deep understanding of adaptive attractor selection-based control formation that is useful to support the designs of adaptive optimization and control in other domains.

  7. Measuring urban rainfall using microwave links from commercial cellular communication networks

    NARCIS (Netherlands)

    Overeem, A.; Leijnse, H.; Uijlenhoet, R.

    2011-01-01

    The estimation of rainfall using commercial microwave links is a new and promising measurement technique. Commercial link networks cover large parts of the land surface of the earth and have a high density, particularly in urban areas. Rainfall attenuates the electromagnetic signals transmitted betw

  8. From Cellular Attractor Selection to Adaptive Signal Control for Traffic Networks

    Science.gov (United States)

    Tian, Daxin; Zhou, Jianshan; Sheng, Zhengguo; Wang, Yunpeng; Ma, Jianming

    2016-03-01

    The management of varying traffic flows essentially depends on signal controls at intersections. However, design an optimal control that considers the dynamic nature of a traffic network and coordinates all intersections simultaneously in a centralized manner is computationally challenging. Inspired by the stable gene expressions of Escherichia coli in response to environmental changes, we explore the robustness and adaptability performance of signalized intersections by incorporating a biological mechanism in their control policies, specifically, the evolution of each intersection is induced by the dynamics governing an adaptive attractor selection in cells. We employ a mathematical model to capture such biological attractor selection and derive a generic, adaptive and distributed control algorithm which is capable of dynamically adapting signal operations for the entire dynamical traffic network. We show that the proposed scheme based on attractor selection can not only promote the balance of traffic loads on each link of the network but also allows the global network to accommodate dynamical traffic demands. Our work demonstrates the potential of bio-inspired intelligence emerging from cells and provides a deep understanding of adaptive attractor selection-based control formation that is useful to support the designs of adaptive optimization and control in other domains.

  9. On the Meta Distribution of Coverage Probability in Uplink Cellular Networks

    KAUST Repository

    Elsawy, Hesham

    2017-04-07

    This letter studies the meta distribution of coverage probability (CP), within a stochastic geometry framework, for cellular uplink transmission with fractional path-loss inversion power control. Using the widely accepted Poisson point process (PPP) for modeling the spatial locations of base stations (BSs), we obtain the percentiles of users that achieve a target uplink CP over an arbitrary, but fixed, realization of the PPP. To this end, the effect of the users activity factor (p) and the path-loss compensation factor () on the uplink performance are analyzed. The results show that decreasing p and/or increasing reduce the CP variation around the spatially averaged value.

  10. A new TDOA algorithm based on Taylor series expansion in cellular networks

    Institute of Scientific and Technical Information of China (English)

    Lingwen ZHANG; Zhenhui TAN

    2008-01-01

    Time difference of arrival (TDOA) is the positioning technique with the most potential in cellular mobile telecommunication systems. The Taylor series expansion method has been widely used in solving nonlinear equations for its high accuracy and good robustness. However, the performance of the Taylor's method depends highly on the initial estimation. Therefore, one new algorithm, hybrid optimizing algo-rithm (HOA) was proposed, which combines the Taylor series expansion method with the steepest decent method. The steepest decent method features fast convergence at the initial iteration and small computation complexity. HOA takes great advantage of both methods. Simulation results show that HOA achieves better performance on positioning accuracy and efficiency.

  11. Green Networking in Cellular HetNets: A Unified Radio Resource Management Framework with Base Station ON/OFF Switching

    KAUST Repository

    Ghazzai, Hakim

    2016-12-07

    In this paper, the problem of energy efficiency in cellular heterogeneous networks (HetNets) is investigated using radio resource and power management combined with the base station (BS) ON/OFF switching. The objective is to minimize the total power consumption of the network while satisfying the quality of service (QoS) requirements of each connected user. We consider the case of co-existing macrocell BS, small cell BSs, and private femtocell access points (FAPs). Three different network scenarios are investigated, depending on the status of the FAPs, i.e., HetNets without FAPs, HetNets with closed FAPs, and HetNets with semi-closed FAPs. A unified framework is proposed to simultaneously allocate spectrum resources to users in an energy efficient manner and switch off redundant small cell BSs. The high complexity dual decomposition technique is employed to achieve optimal solutions for the problem. A low complexity iterative algorithm is also proposed and its performances are compared to those of the optimal technique. The particularly interesting case of semi-closed FAPs, in which the FAPs accept to serve external users, achieves the highest energy efficiency due to increased degrees of freedom. In this paper, a cooperation scheme between FAPs and mobile operator is also investigated. The incentives for FAPs, e.g., renewable energy sharing and roaming prices, enabling cooperation are discussed to be considered as a useful guideline for inter-operator agreements.

  12. Doubly Periodic Traveling Waves in a Cellular Neural Network with Linear Reaction

    Directory of Open Access Journals (Sweden)

    Lin JianJhong

    2009-01-01

    Full Text Available Szekeley observed that the dynamic pattern of the locomotion of salamanders can be explained by periodic vector sequences generated by logical neural networks. Such sequences can mathematically be described by "doubly periodic traveling waves" and therefore it is of interest to propose dynamic models that may produce such waves. One such dynamic network model is built here based on reaction-diffusion principles and a complete discussion is given for the existence of doubly periodic waves as outputs. Since there are 2 parameters in our model and 4 a priori unknown parameters involved in our search of solutions, our results are nontrivial. The reaction term in our model is a linear function and hence our results can also be interpreted as existence criteria for solutions of a nontrivial linear problem depending on 6 parameters.

  13. A Relaying Incentive Scheme in Multihop Cellular Networks Based on Coalitional Game with Externalities

    CERN Document Server

    Li, Cuilian; Tian, Feng

    2008-01-01

    Cooperative multihop communication can greatly increase network throughput, yet packet forwarding for other nodes involves opportunity and energy cost for relays. Thus one of the pre-requisite problems in the successful implementation of multihop transmission is how to foster cooperation among selfish nodes. Existing researches mainly adopt monetary stimulating. In this manuscript, we propose instead a simple and self-enforcing forwarding incentive scheme free of indirect monetary remunerating for asymmetric (uplink multihop, downlink single-hop) cellar network based on coalitional game theory, which comprises double compensation, namely, Inter- BEA, global stimulating policy allotting resources among relaying coalitions according to group size, and Intra-BEA, local compensating and allocating rule within coalitions. Firstly, given the global allotting policy, we introduce a fair allocation estimating approach which includes remunerating for relaying cost using Myerson value for partition function game, to en...

  14. Cellular and network mechanisms generating spontaneous population events in the immature rat hippocampus

    OpenAIRE

    SipilÀ, Sampsa

    2006-01-01

    Distinct endogenous network events, generated independently of sensory input, are a general feature of various structures of the immature central nervous system. In the immature hippocampus, these type of events are seen as "giant depolarizing potentials" (GDPs) in intracellular recordings in vitro. GABA, the major inhibitory neurotransmitter of the adult brain, has a depolarizing action in immature neurons, and GDPs have been proposed to be driven by GABAergic transmission. Moreover, GDPs ha...

  15. Mobility-Aware Caching and Computation Offloading in 5G Ultra-Dense Cellular Networks.

    Science.gov (United States)

    Chen, Min; Hao, Yixue; Qiu, Meikang; Song, Jeungeun; Wu, Di; Humar, Iztok

    2016-06-25

    Recent trends show that Internet traffic is increasingly dominated by content, which is accompanied by the exponential growth of traffic. To cope with this phenomena, network caching is introduced to utilize the storage capacity of diverse network devices. In this paper, we first summarize four basic caching placement strategies, i.e., local caching, Device-to-Device (D2D) caching, Small cell Base Station (SBS) caching and Macrocell Base Station (MBS) caching. However, studies show that so far, much of the research has ignored the impact of user mobility. Therefore, taking the effect of the user mobility into consideration, we proposes a joint mobility-aware caching and SBS density placement scheme (MS caching). In addition, differences and relationships between caching and computation offloading are discussed. We present a design of a hybrid computation offloading and support it with experimental results, which demonstrate improved performance in terms of energy cost. Finally, we discuss the design of an incentive mechanism by considering network dynamics, differentiated user's quality of experience (QoE) and the heterogeneity of mobile terminals in terms of caching and computing capabilities.

  16. Mobility-Aware Caching and Computation Offloading in 5G Ultra-Dense Cellular Networks

    Directory of Open Access Journals (Sweden)

    Min Chen

    2016-06-01

    Full Text Available Recent trends show that Internet traffic is increasingly dominated by content, which is accompanied by the exponential growth of traffic. To cope with this phenomena, network caching is introduced to utilize the storage capacity of diverse network devices. In this paper, we first summarize four basic caching placement strategies, i.e., local caching, Device-to-Device (D2D caching, Small cell Base Station (SBS caching and Macrocell Base Station (MBS caching. However, studies show that so far, much of the research has ignored the impact of user mobility. Therefore, taking the effect of the user mobility into consideration, we proposes a joint mobility-aware caching and SBS density placement scheme (MS caching. In addition, differences and relationships between caching and computation offloading are discussed. We present a design of a hybrid computation offloading and support it with experimental results, which demonstrate improved performance in terms of energy cost. Finally, we discuss the design of an incentive mechanism by considering network dynamics, differentiated user’s quality of experience (QoE and the heterogeneity of mobile terminals in terms of caching and computing capabilities.

  17. Forward Link Power Control Strategy and its Optimum Issue in CDMA Cellular Networks

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In this paper, we propose a theoretical method in order to estimate the forward link outage probability and user capacity of a cellular system which are based on IS-95 CDMA standard, especialy impact of power control strategy and voice activity monitoring in the system under long-term fading effects, in which the light and heavy fadings are considered. According to the numerical results obtained in this paper, the power control strategy leads to approximately the threefold user capacity in contrast to the situation without power control strategy. The reults are compared with Interference-to-Signal Ratio (ISR) driven power control scheme[6][9] which can be used only for simulation of the system. The power control strategy not only improves the desired signal to the interference ratio in the reference user's receiver, but also offers uniform service to the user wherever it is located in the cell.

  18. Hierarchical random cellular neural networks for system-level brain-like signal processing.

    Science.gov (United States)

    Kozma, Robert; Puljic, Marko

    2013-09-01

    Sensory information processing and cognition in brains are modeled using dynamic systems theory. The brain's dynamic state is described by a trajectory evolving in a high-dimensional state space. We introduce a hierarchy of random cellular automata as the mathematical tools to describe the spatio-temporal dynamics of the cortex. The corresponding brain model is called neuropercolation which has distinct advantages compared to traditional models using differential equations, especially in describing spatio-temporal discontinuities in the form of phase transitions. Phase transitions demarcate singularities in brain operations at critical conditions, which are viewed as hallmarks of higher cognition and awareness experience. The introduced Monte-Carlo simulations obtained by parallel computing point to the importance of computer implementations using very large-scale integration (VLSI) and analog platforms.

  19. Numeric reconstruction of 2D cellular actomyosin network from substrate displacement

    Directory of Open Access Journals (Sweden)

    Wagner Shin Nishitani

    Full Text Available Introduction: One of the fundamental structural elements of the cell is the cytoskeleton. Along with myosin, actin microfilaments are responsible for cellular contractions, and their organization may be related to pathological changes in myocardial tissue. Due to the complexity of factors involved, numerical modeling of the cytoskeleton has the potential to contribute to a better understanding of mechanical cues in cellular activities. In this work, a systematic method was developed for the reconstruction of an actomyosin topology based on the displacement exerted by the cell on a flexible substrate. It is an inverse problem which could be considered a phenomenological approach to traction force microscopy (TFM. Methods An actomyosin distribution was found with a topology optimization method (TOM, varying the material density and angle of contraction of each element of the actomyosin domain. The routine was implemented with a linear material model for the bidimensional actomyosin elements and tridimensional substrate. The topology generated minimizes the nodal displacement squared differences between the generated topology and experimental displacement fields obtained by TFM. The structure resulting from TOM was compared to the actin structures observed experimentally with a GFP-attached actin marker. Results The optimized topology reproduced the main features of the experimental actin and its squared displacement differences were 11.24 µm2, 27.5% of the sum of experimental squared nodal displacements (40.87 µm2. Conclusion This approach extends the literature with a model for the actomyosin structure capable of distributing anisotropic material freely, allowing heterogeneous contraction over the cell extension.

  20. Guaranteed Cost Control for Exponential Synchronization of Cellular Neural Networks with Mixed Time-Varying Delays via Hybrid Feedback Control

    Directory of Open Access Journals (Sweden)

    T. Botmart

    2013-01-01

    Full Text Available The problem of guaranteed cost control for exponential synchronization of cellular neural networks with interval nondifferentiable and distributed time-varying delays via hybrid feedback control is considered. The interval time-varying delay function is not necessary to be differentiable. Based on the construction of improved Lyapunov-Krasovskii functionals is combined with Leibniz-Newton's formula and the technique of dealing with some integral terms. New delay-dependent sufficient conditions for the exponential synchronization of the error systems with memoryless hybrid feedback control are first established in terms of LMIs without introducing any free-weighting matrices. The optimal guaranteed cost control with linear error hybrid feedback is turned into the solvable problem of a set of LMIs. A numerical example is also given to illustrate the effectiveness of the proposed method.