Home About us Contact
|
Home About us Contact | ||
|
|
||
System Architecture (system + architecture)
Kinds of System Architecture Selected AbstractsCritical Dialogues: Habermasian Social Theory and International Relations1POLITICS, Issue 3 2005Alexander Anievas The works of Jürgen Habermas have been a theoretical inspiration for many students of international relations (IR). To date, however, the majority of critical IR approaches drawing from the Habermasian perspective have done so on purely philosophical grounds. This article will thus explore the utility of the social-theoretical aspects of Habermas's work for critical inquiries into world politics. To this end, it will examine four main elements of his work: the theory of communicative action; public sphere; lifeworld/system architecture; and discourse ethics. It will be argued that adopting the Habermasian conceptual apparatus provides a social-theoretical route to explaining the contradictory and often paradoxical nature of international relations in the epoch of ,globalisation'. While various constructivist approaches to IR have recently offered more socially-oriented applications of Habermas's theoretical framework, the majority of these studies have done so from predominately non-critical standpoints. This article will thus seek to explore the utility of Habermas's work in offering a critical social theory of world politics. [source] Mobile Construction Supply Chain Management Using PDA and Bar CodesCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 4 2005H. Ping Tserng However, extending the construction project control system to job sites is not considered efficient because using notebooks in a harsh environment like a construction site is not particularly a conventional practice. Meanwhile, paper-based documents of the site processes are ineffective and cannot get the quick response from the office and project control center. Integrating promising information technologies such as personal digital assistants (PDA), bar code scanning, and data entry mechanisms, can be extremely useful in improving the effectiveness and convenience of information flow in construction supply chain control systems. Bar code scanning is appropriate for several construction applications, providing cost savings through increased speed and accuracy of data entry. This article demonstrates the effectiveness of a bar-code-enabled PDA application, called the mobile construction supply chain management (M-ConSCM) System, that responds efficiently and enhances the information flow between offices and sites in a construction supply chain environment. The advantage of the M-ConSCM system lies not only in improving the efficiency of work for on-site engineers, but also providing the Kanban-like visual control system for project participants to control the whole project. Moreover, this article presents a generic system architecture and its implementation. [source] Plug-and-play remote portlet publishingCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 12 2007X. D. Wang Abstract Web Services for Remote Portlets (WSRP) is gaining attention among portal developers and vendors to enable easy development, increased richness in functionality, pluggability, and flexibility of deployment. Whilst currently not supporting all WSRP functionalities, open-source portal frameworks could in future use WSRP Consumers to access remote portlets found from a WSRP Producer registry service. This implies that we need a central registry for the remote portlets and a more expressive WSRP Consumer interface to implement the remote portlet functions. This paper reports on an investigation into a new system architecture, which includes a Web Services repository, registry, and client interface. The Web Services repository holds portlets as remote resource producers. A new data structure for expressing remote portlets is found and published by populating a Universal Description, Discovery and Integration (UDDI) registry. A remote portlet publish and search engine for UDDI has also been developed. Finally, a remote portlet client interface was developed as a Web application. The client interface supports remote portlet features, as well as window status and mode functions. Copyright © 2007 John Wiley & Sons, Ltd. [source] Grid services for earthquake scienceCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 6-7 2002Geoffrey Fox Abstract We describe an information system architecture for the ACES (Asia,Pacific Cooperation for Earthquake Simulation) community. It addresses several key features of the field,simulations at multiple scales that need to be coupled together; real-time and archival observational data, which needs to be analyzed for patterns and linked to the simulations; a variety of important algorithms including partial differential equation solvers, particle dynamics, signal processing and data analysis; a natural three-dimensional space (plus time) setting for both visualization and observations; the linkage of field to real-time events both as an aid to crisis management and to scientific discovery. We also address the need to support education and research for a field whose computational sophistication is rapidly increasing and spans a broad range. The information system assumes that all significant data is defined by an XML layer which could be virtual, but whose existence ensures that all data is object-based and can be accessed and searched in this form. The various capabilities needed by ACES are defined as grid services, which are conformant with emerging standards and implemented with different levels of fidelity and performance appropriate to the application. Grid Services can be composed in a hierarchical fashion to address complex problems. The real-time needs of the field are addressed by high-performance implementation of data transfer and simulation services. Further, the environment is linked to real-time collaboration to support interactions between scientists in geographically distant locations. Copyright © 2002 John Wiley & Sons, Ltd. [source] Access network discovery and selection in the evolved 3GPP multi-access system architectureEUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 6 2010Joachim Sachs The system architecture evolution (SAE) of mobile networks specified in 3GPP release 8 comprises an evolved packet core (EPC) network to which different types of access networks can be connected. Inter-system mobility management enables users to change the access network while maintaining ongoing data sessions. One important functionality in a 3GPP system is how a mobile terminal discovers and selects available access networks. In this paper we describe the access network discovery and selection functionality used in 3GPP release 8; we explain the differences of the methods applied for 3GPP access networks (GERAN, UTRAN, E-UTRAN), for fixed or wireless non-3GPP access networks (e.g. WLAN, WiMAX), as well as the optimisation used for CDMA2000 access networks. Copyright © 2010 John Wiley & Sons, Ltd. [source] TCP-friendly transmission of voice over IPEUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 3 2003F. Beritelli In the last few years an increasing amount of attention has been paid to technologies for the transmission of voice over IP (VoIP). At present, the UDP transport protocol is used to provide this service. However, when the same bottleneck link is shared with TCP flows, and in the presence of a high network load and congestion, UDP sources capture most of the bandwidth, strongly penalizing TCP sources. To solve this problem some congestion control should be introduced for UDP traffic as well, in such a way that this traffic becomes TCP-friendly. In this perspective, several TCP-friendly algorithms have been proposed in the literature. Among them, the most promising candidates for the immediate future are RAP and TFRC. However, although these algorithms were introduced to support real-time applications on the Internet, up to now the only target in optimizing them has been that of achieving fairness with TCP flows in the network. No attention has been paid to the applications using them, and in particular, to the quality of service (QoS) perceived by their users. The target of this paper is to analyze the problem of transmitting voice over IP when voice sources use one of these TCP-friendly algorithms. With this aim, a VoIP system architecture is introduced and the characteristics of each its elements are discussed. To optimize the system, a multirate voice encoder is used so as to be feasible to work over a TCP layer, and a modification of both RAP and TFRC is proposed. Finally, in order to analyze the performance of the proposed system architecture and to compare the modified RAP and TFRC with the original algorithms, the sources have been modeled with an arrival process modulated by a Markov chain, and the model has been used to generate traffic in a simulation study performed with the ns-2 network simulator. Copyright © 2003 AEI. [source] A consideration on R&D direction for future Internet architectureINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 6-7 2010Hiroshi Esaki Abstract The professional Internet system has been operated for more than 20 years, while preserving the continuous introduction of technical innovations. The Internet architecture, of course including the future Internet, must preserve the following five essential features of the Internet architecture. These are (1) autonomous, (2) distributed, (3) disconnected, (4) inter-domain, and (5) global operation. The current Internet system is challenged by the following three aspects; global, ubiquitous and mobility. ISOC, Internet Society (www.isoc.org), has initiated the strategic initiative that is focusing on ,Trust and Identifier'. We must re-design the identifier, directory service, trust model, routing and communication model for the computer system and for the computer networks. For example, Delay Tolerant Networking or Peer-to-Peer system architecture would challenge the introduction of new technological frameworks to the existing Internet. Finally, this paper discusses how to build and how to deploy the future Internet infrastructure. Copyright © 2010 John Wiley & Sons, Ltd. [source] Wireless provision of true VoD services and fast access to InternetINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 5 2002E. Pallis Abstract The evolution of digital compression techniques has made possible the provision of full-motion video services through networking infrastructures of sufficient bandwidth. This paper presents a wireless broadband network, which is capable of providing true interactive VoD services (with full VCR functions) and fast access to Internet to a number of simultaneous clients. The network is based on frequency hopping spread spectrum (FHSS) technology operating in the 2.4 GHz frequency band. The paper describes the system architecture and configuration adopted in a real environment trial and elaborates on the provided picture quality in a multi-client environment. Copyright © 2002 John Wiley & Sons, Ltd. [source] A distributed networking system for multimedia Internet access service using ATM over ADSLINTERNATIONAL JOURNAL OF NETWORK MANAGEMENT, Issue 6 2004Daniel Won-Kyu Hong This paper proposes a distributed networking system architecture for Internet-access service provision using ATM over xDSL technology. We describe the hierarchical network model in deploying ADSL services across the ATM access networks, which can easily accommodate the explosive growth of ADSL subscribers in the future. In addition, this paper describes the distributed networking system and its capability to provide a systemic network management using the principal networking concepts of service ordering, addressing, routing, adaptation and switching. All of the networking system components with CORBA objects in favor of the distribution and location transparency are defined and described using the CORBA interface description language (IDL) for commonality. Lastly, we present its implementation and operation in Korea Telecom.,Copyright © 2004 John Wiley & Sons, Ltd. [source] An overview of the Sirius satellite radio systemINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 5 2008Riza Akturan Abstract This paper presents the system architecture and expected link availability for the Sirius satellite radio system for both the contiguous United States (CONUS) and Canada service regions. Sirius delivers over 100 channels of talk and music to subscribers in CONUS. The service is available to different markets, such as vehicles, homes, portables, marine, and aviation, and is offered on a subscription basis. Descriptions and performance of the Sirius system are detailed herein. Copyright © 2008 John Wiley & Sons, Ltd. [source] Data collection from the Antarctic region through a W-band low Earth orbit satelliteINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 4 2001Marina Ruggieri Abstract The DAVID (DAta and Video Interactive Distribution) mission is being carried out in the framework of the Science Small Missions Program of the Italian Space Agency. The mission is aimed at the deployment of two scientific telecommunication experiments through a low Earth orbit (LEO) satellite. The paper will focus on one of these experiments, that will test a satellite system architecture for the exchange of a large amount of data and high definition images through a W-band link and a Ka-band inter-satellite link between the LEO and the ARTEMIS satellite. The proposed architecture, that will explore various innovative aspects, will also allow for the first time the distribution of large volumes of scientific data collected from the Antarctic region and other extremely remote areas of the Earth. The availability of a return link in the envisaged system will also allow interactive control of the various laboratories located in the remote sites. Copyright © 2001 John Wiley & Sons, Ltd. [source] An architecture for an intelligent support system for design validation and manufacturing of aerospace componentsINTERNATIONAL TRANSACTIONS IN OPERATIONAL RESEARCH, Issue 4 2003Costas Lambrinoudakis Abstract This paper presents the architecture of a multi-agent system that aims to support the design and manufacturing processes of composite material components for the aerospace, automobile, ship and other industries. The major goals are to accelerate the design process while minimising cost; support users in selecting the optimum material in terms of its properties, cost and environmental impact; and enhance the efficiency of the component manufacturing phase by extending the decision support capabilities of the existing real-time monitoring software. An important requirement for achieving these objectives is to enable the more efficient utilisation of existing distributed information on composite materials. To this end, state-of-the-art advances in metadata concepts were adopted and extended. By implementing metadata structures for each data category available, the searching and retrieval mechanisms are improved both in terms of speed and usage. In addition, large amounts of knowledge about the design and manufacturing processes themselves are incorporated into a multi-agent environment in order to enhance the ability to support the user groups involved in the various stages of component design and manufacturing. In order to present the system architecture here, an example from the aerospace industry has been used. [source] Plant and fungal identity determines pathogen protection of plant roots by arbuscular mycorrhizasJOURNAL OF ECOLOGY, Issue 6 2009Benjamin A. Sikes Summary 1.,A major benefit of the mycorrhizal symbiosis is that it can protect plants from below-ground enemies, such as pathogens. Previous studies have indicated that plant identity (particularly plants that differ in root system architecture) or fungal identity (fungi from different families within the Glomeromycota) can determine the degree of protection from infection by pathogens. Here, we test the combined effects of plant and fungal identity to assess if there is a strong interaction between these two factors. 2.,We paired one of two plants (Setaria glauca, a plant with a finely branched root system and Allium cepa, which has a simple root system) with one of six different fungal species from two families within the Glomeromycota. We assessed the degree to which plant identity, fungal identity and their interaction determined infection by Fusarium oxysporum, a common plant pathogen. 3.,Our results show that the interaction between plant and fungal identity can be an important determinant of root infection by the pathogen. Infection by Fusarium was less severe in Allium (simple root system) or when Setaria (complex root system) was associated with a fungus from the family Glomeraceae. We also detected significant plant growth responses to the treatments; the fine-rooted Setaria benefited more from associating with a member of the family Glomeraceae, while Allium benefited more from associating with a member of the family Gigasporaceae. 4.,Synthesis. This study supports previous claims that plants with complex root systems are more susceptible to infection by pathogens, and that the arbuscular mycorrhizal symbiosis can reduce infection in such plants , provided that the plant is colonized by a mycorrhizal fungus that can offer protection, such as the isolates of Glomus used here. [source] Autonomous off-road navigation with end-to-end learning for the LAGR programJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 1 2009Max Bajracharya We describe a fully integrated real-time system for autonomous off-road navigation that uses end-to-end learning from onboard proprioceptive sensors, operator input, and stereo cameras to adapt to local terrain and extend terrain classification into the far field to avoid myopic behavior. The system consists of two learning algorithms: a short-range, geometry-based local terrain classifier that learns from very few proprioceptive examples and is robust in many off-road environments; and a long-range, image-based classifier that learns from geometry-based classification and continuously generalizes geometry to appearance, making it effective even in complex terrain and varying lighting conditions. In addition to presenting the learning algorithms, we describe the system architecture and results from the Learning Applied to Ground Robots (LAGR) program's field tests. © 2008 Wiley Periodicals, Inc. [source] Learning in a hierarchical control system: 4D/RCS in the DARPA LAGR programJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 11-12 2006Jim Albus The Defense Applied Research Projects Agency (DARPA) Learning Applied to Ground Vehicles (LAGR) program aims to develop algorithms for autonomous vehicle navigation that learn how to operate in complex terrain. Over many years, the National Institute of Standards and Technology (NIST) has developed a reference model control system architecture called 4D/RCS that has been applied to many kinds of robot control, including autonomous vehicle control. For the LAGR program, NIST has embedded learning into a 4D/RCS controller to enable the small robot used in the program to learn to navigate through a range of terrain types. The vehicle learns in several ways. These include learning by example, learning by experience, and learning how to optimize traversal. Learning takes place in the sensory processing, world modeling, and behavior generation parts of the control system. The 4D/RCS architecture is explained in the paper, its application to LAGR is described, and the learning algorithms are discussed. Results are shown of the performance of the NIST control system on independently-conducted tests. Further work on the system and its learning capabilities is discussed. © 2007 Wiley Periodicals, Inc. [source] Performance system architecture: Build it, teach it, measure it, and harvest itPERFORMANCE IMPROVEMENT, Issue 8 2005Holly Burkett CPT No abstract is available for this article. [source] N -acyl-L-homoserine lactones: a class of bacterial quorum-sensing signals alter post-embryonic root development in Arabidopsis thalianaPLANT CELL & ENVIRONMENT, Issue 10 2008RANDY ORTÍZ-CASTRO ABSTRACT N -acyl-homoserine lactones (AHLs) belong to a class of bacterial quorum-sensing signals important for bacterial cell-to-cell communication. We evaluated Arabidopsis thaliana growth responses to a variety of AHLs ranging from 4 to 14 carbons in length, focusing on alterations in post-embryonic root development as a way to determine the biological activity of these signals. The compounds affected primary root growth, lateral root formation and root hair development, and in particular, N -decanoyl-HL (C10-HL) was found to be the most active AHL in altering root system architecture. Developmental changes elicited by C10-HL were related to altered expression of cell division and differentiation marker lines pPRZ1:uidA, CycB1:uidA and pAtEXP7:uidA in Arabidopsis roots. Although the effects of C10-HL were similar to those produced by auxins in modulating root system architecture, the primary and lateral root response to this compound was found to be independent of auxin signalling. Furthermore, we show that mutant and overexpressor lines for an Arabidopsis fatty acid amide hydrolase gene (AtFAAH) sustained altered growth response to C10-HL. All together, our results suggest that AHLs alter root development in Arabidopsis and that plants posses the enzymatic machinery to metabolize these compounds. [source] Osmotic regulation of root system architectureTHE PLANT JOURNAL, Issue 1 2005Karen I. Deak Summary Although root system architecture is known to be highly plastic and strongly affected by environmental conditions, we have little understanding of the underlying mechanisms controlling root system development. Here we demonstrate that the formation of a lateral root from a lateral root primordium is repressed as water availability is reduced. This osmotic-responsive regulatory mechanism requires abscisic acid (ABA) and a newly identified gene, LRD2. Mutant analysis also revealed interactions of ABA and LRD2 with auxin signaling. Surprisingly, further examination revealed that both ABA and LRD2 control root system architecture even in the absence of osmotic stress. This suggests that the same molecules that mediate responses to environmental cues can also be regulators of intrinsic developmental programs in the root system. [source] Cross-layer protocol optimization for satellite communications networks: a surveyINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 5 2006Giovanni Giambene Abstract Satellite links are expected to be one important component of the next-generation Internet. New satellite system architectures are being envisaged to be fully IP based and support digital video broadcasting and return channel protocols (e.g. DVB-S, DVB-S2 and DVB-RCS). To make the upcoming satellite network systems fully realizable, meeting new services and application requirements, a complete system optimization is needed spanning the different layers of the OSI, and TCP/IP protocol stack. This paper deals with the cross-layer approach to be adopted in novel satellite systems and architectures. Different cross-layer techniques will be discussed, addressing the interactions among application, transport, MAC and physical layers. The impacts of these techniques will be investigated and numerical examples dealing with the joint optimization of different transport control schemes and lower layers will be considered referring to a geostationary-based architecture. Our aim is to prove that the interaction of different layers can permit to improve the higher-layer goodput as well as user satisfaction. Copyright © 2006 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||