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Network Development (network + development)
Selected AbstractsPhotonic circuits writing with UV pulsed laserPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 1 2007K. R. Kribich Abstract Photonics technology is employed in a growing number of applications. Biological and chemical sensors (E. Udd, Fiber Optic Sensors: An Introduction for Engineers and Scientists, Wiley, New York, 1991 [1]) for health and environment demand an adaptable technology. Network development towards the end-user requires more interconnecting components. Vision, lighting, data processing in hostile environment (spatial, military) need specific technologies. A flexible and low-cost process using good quality material is necessary. The sol-gel process is a chemical method to fabricate glasses at ambient pressure and moderate temperature. Hybrid materials (H.K. Schmidt et al., Proc. SPIE 3136, 220 (1997) [2]), mixing organic and inorganic parts, offer the advantages of polymer-like materials and glasses. We report on a new hybrid sol-gel technology to overcome the drawbacks of the formerly presented one (H. Krug, F. Teillantes, P.W. Oliviers, and H. Schmidt, Proc. SPIE 1758, 448 (1992) [3]). We present the material synthesis, an accurate and flexible fabrication process based on a pulsed UV laser lithography system and the characterisation of the optical waveguides and photonic circuits realised. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Cultural-historical activity theory as practice theory: illuminating the development of conflict-monitoring networkCOMMUNICATION THEORY, Issue 1 2001Kirsten A. Foot As the number and intensity of conflicts increased around the world during the latter part of the 20th century, scholars, policymakers, and practitioners of non-violent conflict management strategies created conflict-monitoring networks to track the escalation of tensions in conflict-prone regions. This essay demonstrates how cultural-historical activity theory (CHAT) was employed in the service of a conflict-monitoring network in the former Soviet Union. Based upon historical and participant observation research on the development of the Network for Ethnological Monitoring and Early Warning during 1990,1999, a CHAT-based analysis of the Network's systemic contradictions illuminates its development through one expansive cycle and into a second. Summaries of findings consider relations within the Network, the evolution of the Network's complex object, and the Network's development of tools for monitoring ethnic relations and building an epistemic community. The essay concludes with an analysis of the correspondence between the CHAT framework and the 5 features of practical theory laid out by Cronen (1995). [source] Nonlinear epigenetic variance: review and simulationsDEVELOPMENTAL SCIENCE, Issue 1 2010Kees-Jan Kan We present a review of empirical evidence that suggests that a substantial portion of phenotypic variance is due to nonlinear (epigenetic) processes during ontogenesis. The role of such processes as a source of phenotypic variance in human behaviour genetic studies is not fully appreciated. In addition to our review, we present simulation studies of nonlinear epigenetic variance using a computational model of neuronal network development. In each simulation study, time series for monozygotic and dizygotic twins were generated and analysed using conventional behaviour genetic modelling. In the results of these analyses, the nonlinear epigenetic variance was subsumed under the non-shared environmental component. As is commonly found in behaviour genetic studies, observed heritabilities and unique environmentabilities increased with time, whereas common environmentabilities decreased. The fact that the phenotypic effects of nonlinear epigenetic processes appear as unsystematic variance in conventional twin analyses complicates the identification and quantification of the ultimate genetic and environmental causes of individual differences. We believe that nonlinear dynamical system theories provide a challenging perspective on the development of individual differences, which may enrich behaviour genetic studies. [source] Experimental study of rill bank collapseEARTH SURFACE PROCESSES AND LANDFORMS, Issue 2 2007Jovan R. Stefanovic Abstract Rill bank collapse is an important component in the adjustment of channel morphology to changes in discharge and sediment flux. Sediment inputs from bank collapse cause abrupt changes in flow resistance, flow patterns and downstream sediment concentrations. Generally, bank retreat involves gradual lateral erosion, caused by flow shear stress, and sudden bank collapse, triggered by complex interactions between channel flow and bank and soil water conditions. Collapse occurs when bank height exceeds the critical height where gravitational forces overcome soil shear strength. An experimental study examined conditions for collapse in eroding rill channels. Experiments with and without a deep water table were carried out on a meandering rill channel in a loamy sand and sandy loam in a laboratory flume under simulated rainfall and controlled runon. Different discharges were used to initiate knickpoint and rill incision. Soil water dynamics were monitored using microstandpipes, tensiometers and time domain reflectometer probes (TDR probes). Bank collapse occurred with newly developed or rising pre-existing water tables near rill banks, associated with knickpoint migration. Knickpoint scour increased effective bank height, caused positive pore water pressure in the bank toe and reduced negative pore pressures in the unsaturated zone to near zero. Matric tension in unsaturated parts of the bank and a surface seal on the ,interrill' zone behind the bank enhanced stability, while increased effective bank height and positive pore water pressure at the bank toe caused instability. With soil water contents >35 per cent (sandy loam) and >23 per cent (loamy sand), critical bank heights were 0·11,0·12 m and 0·06,0·07 m, respectively. Bank toe undercutting at the outside of the rill bends also triggered instability. Bank displacement was quite different on the two soils. On the loamy sand, the failed block slid to the channel bed, revealing only the upper half of the failure plane, while on the sandy loam the failed block toppled forwards, exposing the failure plane for the complete bank height. This study has shown that it is possible to predict location, frequency and magnitude of the rill bank collapse, providing a basis for incorporation into predictive models for hillslope soil loss or rill network development. Copyright © 2006 John Wiley & Sons, Ltd. [source] Planning for Path Dependence?ECONOMIC GEOGRAPHY, Issue 2 2010The Case of a Network in the Berlin-Brandenburg Optics Cluster abstract Much research on regional business clusters refers to path dependence as a central feature in the evolution of cluster structures. In many cases, however, little is known about the agentic processes and mechanisms that underlie path dependence. In this article, we explore changes in a specific network in the optics cluster in the German region of Berlin-Brandenburg to show that development of clusters can be driven by elements of both emergence and planning. In particular, we argue that current actors actively and purposively draw upon rules and resources that were shaped not only in the long and discontinuous history of the cluster but also in the recent process of network development that involves careful planning and well-structured planning tools. Using central concepts from structuration theory, we show how agency is implicated in the coordination of the network and how agency turns coordination into a self-reinforcing mechanism. The findings suggest that purposive planning involves a fundamental ambivalence in the processes and outcomes of path dependence, at the level of both the cluster and its constituent networks. [source] Entrepreneurship Research on Network Processes: A Review and Ways ForwardENTREPRENEURSHIP THEORY AND PRACTICE, Issue 1 2010Susanna Slotte-Kock Although entrepreneurship research on networks has studied issues pertaining to network content, governance and structure, we believe it requires a greater understanding of network processes. In this paper, we review how the entrepreneurship literature interprets and applies the concept of process to the study of networks. This allows us to identify areas for future investigation. Our work is also informed by social network theory and research on dyadic interactions in business networks. The paper concludes by presenting a theoretical framework for conceptualizing and studying the various processes associated with network development. [source] From rhetoric to reality: including patient voices in supportive cancer care planningHEALTH EXPECTATIONS, Issue 3 2005Sara K. Tedford Gold PhD Abstract Objective, To explore the extent and manner of patient participation in the planning of regional supportive care networks throughout the province of Ontario. We consider the disconnect between the rhetoric and reality of patient involvement in network planning and co-ordination. Context, In 1997, the Province of Ontario, Canada, established a new, regionalized cancer care system. By transferring responsibility to the regional level and to networks, the architects of the new provincial system hoped to broaden participation in decision making and to enhance the responsiveness of decisions to communities. Research approach, Through a qualitative, multiple case study approach we evaluated the processes of involving patients in network development. In-depth, semi-structured interviews and document analysis were complemented by observations of provincial meetings, regional council and network meetings. Results, The network development processes in the three case study regions reveal a significant gap between intentions to involve patients in health planning and their actual involvement. This gap can be explained by: (i) a lack of clear direction regarding networks and patient participation in these networks; (ii) the dominance of regional cancer centres in network planning activities; and, (iii) the emergence of competing provincial priorities. Discussion, These three trends expose the complexity of the notion of public participation and how it is embedded in social and political contexts. The failed attempt at involving patients in health planning efforts is the result of benign neglect of public participation intents and the social and political contexts in which public and patient participation is meant to occur. [source] Commentary on Kewell et al. (2002), Calman,Hine reassessed: a survey of cancer network development in England, 1999,2000.JOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 3 2002Journal of Evaluation in Clinical Practice [source] Calman,Hine reassessed: a survey of cancer network development in England, 1999,2000JOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 3 2002Beth Kewell BA PhD Abstract Rationale, aims and objectives,The paper assesses preliminary national data on the development of cancer care networks in England. Methods,In January 2000, a national postal survey was sent to lead clinicians at 36 cancer centres and associate centres. Respondents were asked to provide basic numerical data on the design of the network (i.e. its configuration), detailing how many units it encompassed, and whether the centre was a multiple or a single entity. Results,The survey highlighted national variations in the size and configuration of networks. The survey also highlighted tentative signs of shifts in clinical practice. The results showed that consultants at cancer centres and units were engaging in two forms of collaboration across centre,unit boundaries. Type 1 involved routine multidisciplinary team (MDT) outreach from centres to units, incorporating joint planning between clinicians at cancer centres and cancer units. Type 2 collaboration involved joint planning but also promoted joint centre and unit training and continuing professional development (CPD) programmes. Conclusions,In our estimation, both forms of collaboration represented early evidence of qualitative changes in medical working practices. Organizational changes within cancer services have moved swiftly since initial soundings were taken in 2000 and we update our initial commentary in the light of recent empirical data. The findings may be of wider significance to managers and health practitioners who are working towards the implementation of delivery network elsewhere in the UK National Health Service. [source] U-PVC gelation level assessment, part 1: Comparison of different techniquesJOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 3 2006Louise-Anne Fillot Several different gelation assessment methods such as differential scanning calorimetry, capillary rheometry, solvent absorption, wide angle x-ray scattering, transmission electron microscopy, and atomic force microscopy were applied to a typical PVC window profile formulation subjected to various thermomechanical histories. Shear applied during the process could be decomposed into two components: (i) a thermal component corresponding to the self-heating that was generated and (ii) a "mechanical" component associated with a "pure" shearing action deprived of any thermal aspect. Shear sensitivity of the above-mentioned gelation assessment techniques was evaluated by considering both aspects. Gelation levels established by differential scanning calorimetry and capillary rheometry were especially compared, thus allowing a comparison of the two physical aspects evidenced by each technique, i.e., crystallite melting and macromolecular network development. It appeared that as soon as the PVC particulate structure had been fragmented into micronic entities (primary particles) the gelation process was governed mainly by the thermal aspect, i.e., crystallite melting. J. VINYL. ADDIT. TECHNOL. 12:98,107, 2006. © 2006 Society of Plastics Engineers. [source] Transforming the Delivery of Rural Health Care in Georgia: State Partnership Strategy for Developing Rural Health NetworksTHE JOURNAL OF RURAL HEALTH, Issue 5 2003Karen J. Minyard PhD ABSTRACT: Since 1996, 19 networks covering 74 of the 127 rural counties in Georgia have emerged. This grassroots transformation of rural health care occurred through a series of partnerships launched by state government officials. These partnerships brought together national and state organizations to pool resources for investment in an evolving long-term strategy to develop rural health care networks. The strategy leveraged resources from partners, resulting in greater impact. Change was triggered and accelerated using an intensive, flexible technical assistance effort amplified by developmental grants to communities. These grants were made available for structural and organizational change in the community that would eventually lead to improved access and health status. Georgia's strategy for developing rural health networks consisted of 3 elements: a clear state vision and mission; investment partnerships; and proactive, flexible technical assistance. Retrospectively, it seems that the transformation occurred as a result of 5 phases of investment by state government and its partners. The first 2 phases involved data gathering as well as the provision of technical assistance to individual communities. The next 3 phases moved network development to a larger scale by working with multiple counties to create regional networks. The 5 phases represent increasing knowledge about and commitment to the vision of access to care and improved health status for rural populations. [source] Investigating the surface process response to fault interaction and linkage using a numerical modelling approachBASIN RESEARCH, Issue 3 2006P.A. Cowie ABSTRACT In order to better understand the evolution of rift-related topography and sedimentation, we present the results of a numerical modelling study in which elevation changes generated by extensional fault propagation, interaction and linkage are used to drive a landscape evolution model. Drainage network development, landsliding and sediment accumulation in response to faulting are calculated using CASCADE, a numerical model developed by Braun and Sambridge, and the results are compared with field examples. We first show theoretically how the ,fluvial length scale', Lf, in the fluvial incision algorithm can be related to the erodibility of the substrate and can be varied to mimic a range of river behaviour between detachment-limited (DL) and transport-limited (TL) end-member models for river incision. We also present new hydraulic geometry data from an extensional setting which show that channel width does not scale with drainage area where a channel incises through an area of active footwall uplift. We include this information in the coupled model, initially for a single value of Lf, and use it to demonstrate how fault interaction controls the location of the main drainage divide and thus the size of the footwall catchments that develop along an evolving basin-bounding normal fault. We show how erosion by landsliding and fluvial incision varies as the footwall area grows and quantify the volume, source area, and timing of sediment input to the hanging-wall basin through time. We also demonstrate how fault growth imposes a geometrical control on the scaling of river discharge with downstream distance within the footwall catchments, thus influencing the incision rate of rivers that drain into the hanging-wall basin. Whether these rivers continue to flow into the basin after the basin-bounding fault becomes fully linked strongly depends on the value of Lf. We show that such rivers are more likely to maintain their course if they are close to the TL end member (small Lf); as a river becomes progressively more under supplied, i.e. the DL end member (large Lf), it is more likely to be deflected or dammed by the growing fault. These model results are compared quantitatively with real drainage networks from mainland Greece, the Italian Apennines and eastern California. Finally, we infer the calibre of sediments entering the hanging-wall basin by integrating measurements of erosion rate across the growing footwall with the variation in surface processes in space and time. Combining this information with the observed structural control of sediment entry points into individual hanging-wall depocentres we develop a greater understanding of facies changes associated with the rift-initiation to rift-climax transition previously recognised in syn-rift stratigraphy. [source] | ||||||||||||||||