• Title/Summary/Keyword: global networks

Search Result 881, Processing Time 0.031 seconds

Conceptual design and preliminary characterization of serial array system of high-resolution MEMS accelerometers with embedded optical detection

  • Perez, Maximilian;Shkel, Andrei
    • Smart Structures and Systems
    • /
    • v.1 no.1
    • /
    • pp.63-82
    • /
    • 2005
  • This paper introduces a technology for robust and low maintenance cost sensor network capable to detect accelerations below a micro-g in a wide frequency bandwidth (above 1,000 Hz). Sensor networks with such performance are critical for navigation, seismology, acoustic sensing, and for the health monitoring of civil structures. The approach is based on the fabrication of an array of high sensitivity accelerometers, each utilizing Fabry-Perot cavity with wavelength-dependent reflectivity to allow embedded optical detection and serialization. The unique feature of the approach is that no local power source is required for each individual sensor. Instead one global light source is used, providing an input optical signal which propagates through an optical fiber network from sensor-to-sensor. The information from each sensor is embedded onto the transmitted light as an intrinsic wavelength division multiplexed signal. This optical "rainbow" of data is then assessed providing real-time sensing information from each sensor node in the network. This paper introduces the Fabry-Perot based accelerometer and examines its critical features, including the effects of imperfections and resolution estimates. It then presents serialization techniques for the creation of systems of arrayed sensors and examines the effects of serialization on sensor response. Finally, a fabrication process is proposed to create test structures for the critical components of the device, which are dynamically characterized.

Deployment Strategy of ARGO Floats in the East Sea (동해 ARGO 플로트의 투하 전략)

  • Park, Jong Jin;Park, Jong Sook
    • Ocean and Polar Research
    • /
    • v.37 no.3
    • /
    • pp.179-188
    • /
    • 2015
  • This study was carried out to determine the optimal number of ARGO floats in the East Sea in order to maximize their applications. The dominant spatio-temporal scale, size of the domain, and the typical float lifetimes in the East Sea were taken into consideration. The mean spatial de-correlation scale of temperature on isobaric surfaces reaches about 60 km. The minimum necessary number of floats is about 82 on average in order to secure independent ARGO profiles with the de-correlation scale. Considering the float lifetimes, about 27 floats per year should be deployed to maintain the 82 ARGO float array every year. To obtain spatially uniform distribution of ARGO float data, mean residence time and dispersion rate (basin area/residence time) of ARGO floats were evaluated in each basin of the East Sea. A faster (slower) dispersion rate requires more (less) ARGO floats to maintain the spatially uniform number of floats. According to the analysis, it is likely that the optimal ratio of the number of floats for each basin is 1:2:4 corresponding to Ulleung Basin:Yamato Basin:Japan Basin. In order to maintain relatively uniform ARGO observing networks, it is necessary to establish a long-term plan for deployment strategy based on float pathways and the dispersion rate parameters estimated by using currently active ARGO float trajectory data as well as reanalysis data.

A study on Korean Free Zone and it's growing strategy (우리나라의 동북아 물류거점화전략과 관세자유지역제도의 발전방향)

  • Kang, Jong-Hi;Woo, Jong-Kyun
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
    • /
    • v.16
    • /
    • pp.117-154
    • /
    • 2001
  • The objective of the study is to propose to the strategy to make korean main ports to international logistics center in Northeast Asia. so this study's construction is constructed four steps. First, analysis the environment of economy, business and logistics industry in Northeast Asia. Second, analysis the constructions and characters of Free Zone Act. Third, analysis of Korean Government's policy about Free Zone. Forth, propose the growing strategy of Free Zone. In 1999 Northeast Asia was adopted in Korea, which will facilitate the process and strengthen the international logistics capability as a international logistics hub in Northeast Asia. But only adoption in the point of law is not enough to growing korean main seaport and airport to a international logistics hub. so various strategies are needed. In this study, we propose the growing strategies that are to establish and manage the free zone of ports and its hinterland are: the establishment of a long-term vision of international logistics complexes, the improvement of the proximity to markets/customers by way of linkage of global networks, the activation of the industrial complex in hinterland, the development of the skilled labor and the labor climate, the cooperation between governmental bodies and government/provincial bodies, continuous development of logistics infrastructure and so on.

  • PDF

A congestion control scheme estimating global channel busy ratio in VANETs

  • Kim, Tae-won;Jung, Jae-il;Lee, Joo-young
    • Journal of IKEEE
    • /
    • v.21 no.2
    • /
    • pp.115-122
    • /
    • 2017
  • In vehicular safety service, every vehicle broadcasts Basic Safety Message (BSM) periodically to inform neighbor vehicles of host vehicle information. However, this can cause network congestion in a region that is crowded with vehicles resulting in a reduction in the message delivery ratio and an increase in the end-to-end delay. Therefore, it could destabilize the vehicular safety service system. In this paper, in order to improve the congestion control and to consider the hidden node problem, we propose a congestion control scheme using entire network congestion level estimation combined with transmission power control, data rate control and time slot based transmission control algorithm. The performance of this scheme is evaluated using a Qualnet network simulator. The simulation result shows that our scheme mitigates network congestion in heavy traffic cases and enhances network capacity in light traffic cases, so that packet error rate is perfectly within 10% and entire network load level is maintained within 60~70%. Thus, it can be concluded that the proposed congestion control scheme has quite good performance.

A Case Study on the Usage of Mobile Banking Service (농협의 모바일 뱅킹 서비스 사례)

  • Kim, Byung-Gon
    • Proceedings of the Korea Database Society Conference
    • /
    • 2010.06a
    • /
    • pp.249-264
    • /
    • 2010
  • Mobile banking is a subset of electronic banking which underlies not only the determinants of the banking business but also the special conditions of mobile commerce. Nowadays wireless networks are being evolved and diversified. In this situation The wireless e-commerce is in the limelight on new profits of Carriers. Because of this situation, the importance of mobile billing service is being emphasized. This paper searches the definition and service types of mobile banking, and suggests status and prospects of domestic mobile banking. We suggest the basic direction, the stage of development and functions of services by analyzing the cases of Nonghyup's. Finally we derive the critical factors from those and suggest the effect of introduction and the direction of development. From the customer perspective, mobile banking has many strengths. For example, it allows that all customers access banking service at anytime, anywhere more easily than telephone banking or pc banking. And it reduces the time and the effort for using the service. It enables the company to make a business against global customers. On the other hand, from the company perspective, it has a lot of potential that affect market share and reduce the costs of human and material resources which used to operate and support branches. However, it needs many efforts to reach at the stage of completion. And We will have to solve the problems that develop many contents, expend the range of services and raise the service convenience.

  • PDF

Musical Identity Online: A "Netnographic" Perspective of Online Communities

  • Strubel, Jessica;Pookulangara, Sanjukta;Murray, Amber
    • International Journal of Costume and Fashion
    • /
    • v.13 no.2
    • /
    • pp.15-29
    • /
    • 2013
  • Today's technology enables consumers to trade millions of dollars, conduct online banking, access entertainment, and do countless other activities at the click of a button. Online social networks (OSN) have become a cultural phenomenon that allows for individualistic consumerism. Consumers are increasingly utilizing OSN to share ideas, build communities, and contact fellow consumers who are similar to themselves. The relevance of online communities to the music is immense especially because musicians are now using social media to build global audiences. Not only is information about music and performance disseminated online, but musical commodities are sold and traded online. Online music communities allow consumers to elect and create new identities online through the purchase of subcultural commodities. Given the growing economic importance of online music communities it is important to get a holistic view of subcultural communities online. This study utilized content analysis of online music community websites using the Netnography methodology as developed by Kozinet for data collection to analyze consumers' purchasing and consumption behavior of subcultural commodities online as related to the formation of subcultural identities. Findings showed that subcultural items are predominantly purchased online, especially digital music, and there is a need for more custom craft items. The authors presented a new conceptual taxonomy of online subcultural consumer classifications based on online behavior patterns.

Redundant rule Detection for Software-Defined Networking

  • Su, Jian;Xu, Ruoyu;Yu, ShiMing;Wang, BaoWei;Wang, Jiuru
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.14 no.6
    • /
    • pp.2735-2751
    • /
    • 2020
  • The emergence of Software Defined Networking (SDN) overcomes the limitations of traditional networking architectures. There are some advantages in SDN which are centralized global network view, programmability, and separation of the data plane and control plane. Due to the limitation of data plane storage capacity in SDN, it is necessary to process the redundancy rules of switch. In this paper, we propose a method for active detection and processing of redundant rules. We use the result generated by the customized probe package to detect redundant rules. And by checking the forwarding behavior of probe packets in the data plane, the redundancy rules are further processed. Furthermore, in order to quickly check the dynamic networks, we propose an incremental algorithms for rapidly evolve the network strategies. We conduct simulation experiments on Matlab to verify the feasibility of the algorithm. The influence of some parameters on the result are discussed.

Regulatory Network of MicroRNAs, Host Genes, Target Genes and Transcription Factors in Human Esophageal Squamous Cell Carcinoma

  • Wang, Tian-Yan;Xu, Zhi-Wen;Wang, Kun-Hao;Wang, Ning
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.9
    • /
    • pp.3677-3683
    • /
    • 2015
  • Abnormally expressed microRNAs (miRNAs) and genes have been found to play key roles in esophageal squamous cell carcinoma (ESCC), but little is known about the underlying mechanisms. The aim of this paper was to assess inter-relationships and the regulatory mechanisms of ESCC through a network-based approach. We built three regulatory networks: an abnormally expressed network, a related network and a global network. Unlike previous examples, containing information only on genes or miRNAs, the prime focus was on relationships. It is worth noting that abnormally expressed network emerged as a fault map of ESCC. Theoretically, ESCC might be treated and prevented by correcting the included errors. In addition, the predicted transcription factors (TFs) obtained by the P-match method also warrant further study. Our results may further guide gene therapy researchers in the study of ESCC.

Swarm Intelligence-based Power Allocation and Relay Selection Algorithm for wireless cooperative network

  • Xing, Yaxin;Chen, Yueyun;Lv, Chen;Gong, Zheng;Xu, Ling
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.10 no.3
    • /
    • pp.1111-1130
    • /
    • 2016
  • Cooperative communications can significantly improve the wireless transmission performance with the help of relay nodes. In cooperative communication networks, relay selection and power allocation are two key issues. In this paper, we propose a relay selection and power allocation scheme RS-PA-PSACO (Relay Selection-Power Allocation-Particle Swarm Ant Colony Optimization) based on PSACO (Particle Swarm Ant Colony Optimization) algorithm. This scheme can effectively reduce the computational complexity and select the optimal relay nodes. As one of the swarm intelligence algorithms, PSACO which combined both PSO (Particle Swarm Optimization) and ACO (Ant Colony Optimization) algorithms is effective to solve non-linear optimization problems through a fast global search at a low cost. The proposed RS-PA-PSACO algorithm can simultaneously obtain the optimal solutions of relay selection and power allocation to minimize the SER (Symbol Error Rate) with a fixed total power constraint both in AF (Amplify and Forward) and DF (Decode and Forward) modes. Simulation results show that the proposed scheme improves the system performance significantly both in reliability and power efficiency at a low complexity.

Extended 3-Party Mutual Authentication Protocols for the Virtual Home Environment in Next Generation Mobile Networks (차세대 이동통신 네트워크의 Virtual Home Environment 구조에 적용 가능한 3자간 상호 인증 프로토콜)

  • Jeong, Jong-Min;Lee, Goo-Yeon;Lee, Yong
    • Journal of the Institute of Electronics Engineers of Korea TC
    • /
    • v.40 no.4
    • /
    • pp.22-29
    • /
    • 2003
  • In the virtual home environment (VHE), which was proposed to offer global roaming and personal service environment portability, user's profiles and service logics are conveyed from home network to visited network to provide services at the visited network. Because user's profiles and service logics may contain confidential information, some procedures for mutual authentication among entities for offering confidence are needed. For these issues, we propose and analyze three 3-Party mutual authentication Protocols adaptable to the VHE in 3G ; password based mutual authentication protocol, mutual authentication protocol with CHAP and key exchange and mutual authentication protocol with trusted third party.