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[en] Internet is often used for transaction based applications such as online banking, stock trading and shopping, where the service interruption or outages are unacceptable. Therefore, it is important for designers of such applications to analyze how hardware, software and performance related failures affect the quality of service delivered to the users. This paper presents analytical models for evaluating the service availability of web cluster architectures. A composite performance and availability modeling approach is defined considering various causes of service unavailability. In particular, web cluster systems are modeled taking into account: two error recovery strategies (client transparent and non-client-transparent) as well as two traffic models (Poisson and modulated Poisson). Sensitivity analysis results are presented to show their impact on the web service availability. The obtained results provide useful guidelines to web designers
[en] At Belle II, detector signals are digitized inside or near the detector and collected via high-speed optical serial links. Each frontend digitization board equips an FPGA for a unified data link and timing system interface to receive the system clock, the level-1 trigger, other fast timing signals and to return status signals. Timing signals are serialized and delivered via a commodity category-7 LAN cable, through a tree-structure distribution network made from cascaded 1-to-20 distribution modules. We report the performance of this timing distribution system.
[en] The Industrial Internet of Things (IIoT) is the industrial subset of the Internet of Things (IoT). IIoT incorporates big data technology, harnessing the instrumentation data, machine to machine communication and automation technologies that have existed in industrial settings for years. As industry in general trends towards the IIoT and as the screw compressor packages developed by Howden Compressors are designed with a minimum design life of 25 years, it is imperative this technology is embedded immediately. This paper provides the reader with a description on the Industrial Internet of Things before moving onto describing the scope of the problem for an organisation like Howden Compressors who deploy multiple compressor technologies across multiple locations and focuses on the critical measurements particular to high specification screw compressor packages. A brief analysis of how this differs from high volume package manufacturers deploying similar systems is offered. Then follows a description on how the measured information gets from the tip of the instrument in the process pipework or drive train through the different layers, with a description of each layer, into the final presentation layer. The functions available within the presentation layer are taken in turn and the benefits analysed with specific focus on efficiency and availability. The paper concludes with how packagers adopting the IIoT can not only optimise their package but by utilising the machine learning technology and pattern detection applications can adopt completely new business models. (paper)
[en] This paper presents the research developed at Universidad Nacional de Colombia about the e-Manufacturing platform that is being developed and implemented at LabFabEx (acronym in Spanish as "Laboratorio Fabrica Experimental"). This platform besides has an approach to virtual-remote labs that have been tested by several students and engineers of different industrial fields. At this paper it is shown the physical and communication experimental platform, the general scope and characteristics of this e-Manufacturing platform and the virtual lab approach. This research project is funded by COLCIENCIAS (Administrative Department of science, technology and innovation in Colombia) and the enterprise IMOCOM S.A
[en] Programmable logic controllers (PLCs) are widely used to realize slow control and interlock control of the accelerator control system. Along with the development of the industrial control technology, data exchanging between PLC and upper computer is usually based on the ethernet communication. An embedded IOC prototype was built for communication between PLC and EPICS using the YOKOGAWA FA-M3 PLC and a new CPU module F3RP61. The embedded EPICS IOC Core was run in F3RP61, which makes the FA-M3 PLC with F3RP61 becomes a new type of embedded IOC. Therefore, the data of the FA-M3 PLC can go straight into the EPICS. This framework makes the structure of the control system simple. As a result, the development costs will be reduced. (authors)
[en] We describe the Ethernet systems and their evolution: LAN Segmentation, DUAL networks, network loops, network redundancy and redundant network access. Ethernet (IEEE 802.3) is an open standard with no licensing fees and its specifications are freely available. As a result, it is the most popular data link protocol in use. It is important that the network be redundant and standard Ethernet protocols like RSTP (IEEE 802.1w) provide the fast network fault detection and recovery times that is required today. As Ethernet does continue to evolve, network redundancy is and will be a mixture of technology standards. So it is very important that both end-stations and networking devices be Ethernet (IEEE 802.3) compliant. Then when new technologies, such as the IEEE 802.1aq Shortest Path Bridging protocol, come to market they can be easily deployed in the network without worry
[en] Structural health monitoring system should developed to be based on internet and database technology in order to manage efficiently large structures. This system is operated by internet connected with the side of structures. The monitoring system has some functions: self monitoring, self diagnosis, and self control etc. Self monitoring is the function of sensor fault detection. If some sensors are not normally worked, then this system can detect the fault sensors. Also Self diagnosis function repair the abnormal condition of sensors. And self control is the repair function of the monitoring system. Especially, the monitoring system can identify the replacement of sensors. For further study, the real application test will be performed to check some unconvince.
[en] Network mobility basic support (NEMO BS) protocol is an entire network, roaming as a unit which changes its point of attachment to the Internet and consequently its reachability in the network topology. NEMO BS doesn't provide QoS guarantees to its users same as traditional Internet IP and Mobile IPv6 as well. Typically, all the users will have same level of services without considering about their application requirements. This poses a problem to real-time applications that required QoS guarantees. To gain more effective control of the network, incorporated QoS is needed. Within QoS-enabled network the traffic flow can be distributed to various priorities. Also, the network bandwidth and resources can be allocated to different applications and users. Internet Engineering Task Force (IETF) working group has proposed several QoS solutions for static network such as IntServ, DiffServ and MPLS. These QoS solutions are designed in the context of a static environment (i.e. fixed hosts and networks). However, they are not fully adapted to mobile environments. They essentially demands to be extended and adjusted to meet up various challenges involved in mobile environments. With existing QoS mechanisms many proposals have been developed to provide QoS for individual mobile nodes (i.e. host mobility). In contrary, research based on the movement of the whole mobile network in IPv6 is still undertaking by the IETF working groups (i.e. network mobility). Few researches have been done in the area of providing QoS for roaming networks. Therefore, this paper aims to review and investigate (previous /and current) related works that have been developed to provide QoS in mobile network. Consequently, a new proposed scheme will be introduced to enhance QoS within NEMO environment, achieving by which seamless mobility to users of mobile network node (MNN)
[en] In the framework of the CARE HHH European Network, we have developed a web-based dynamic accelerator-physics code repository. We describe the design, structure and contents of this repository, illustrate its usage, and discuss our future plans, with emphasis on code benchmarking