Corridor Concept Research Articles

Green Corridors in European Surface Freight Logistics and the SuperGreen Project

“Green corridors” is an EU concept introduced in 2007 that aims at developing integrated, efficient and environmentally friendly transportation of freight between major hubs and by relative long distances. SuperGreen is a project co-financed by the European Commission to assist in further defining and developing the green corridor concept. A central activity of the project is the development of a corridor benchmarking methodology using a set of Key Performance Indicators that are suitable for monitoring the sustainable development goals of the European Union. The purpose of this paper is to present the SuperGreen project and the results achieved so far.

Elastic and adaptive optical networks: possible adoption scenarios and future standardization aspects

There is growing recognition that we are rapidly approaching the physical capacity limit of standard optical fiber. It is important to make better use of optical network resources to accommodate the ever-increasing traffic demand. One promising way is to introduce elasticity and adaptation into the optical domain through more flexible spectrum allocation, where the required minimum spectral resources are allocated adaptively based on traffic demand and network conditions. In this article, we discuss elastic and adaptive optical networks from the perspective of future standardization. We first overview the architecture, enabling technologies, and benefits of elastic and adaptive optical networks with the new concept of an optical corridor. We then present possible adoption scenarios from current rigid optical networks to elastic and adaptive optical networks. We discuss some possible study items that are relevant to the future standardization activities. These items include optical transport network architecture, structure and mapping of the optical transport unit, automatically switched optical network/generalized multiprotocol label switching control plane issues, and some physical aspects with possible extension of the current frequency grid.

Mastering tacit corridors for competitive advantage: Cross‐cultural knowledge creation and sharing at four international firms

AbstractIn today's business world, knowledge is shaped in corporate relationships and diffused in networks. A major mode of knowledge is the tacit dimension, which refers to the elusive, uncodified knowledge that comes from experience, is hard to quantify, but gives an all‐important mood and tone to explicit knowledge. Tacit knowledge is traditionally viewed as an important though hazily conceived organizational asset; however, here it is treated as something that is co‐created in cross‐cultural business relationships and as a knowledge resource of immense significance. Tacit knowledge is prone to serious misappreciation by managers, but understanding it for what it is can give firms a key edge that the authors term knowledge advantage. Here, they use case‐study data from four international firms to introduce a model that makes use of the concepts of tacit corridors and coupling. Tacit corridors are the metaphorical spaces in cross‐cultural interactions where managers' thoughts and actions are constrained—often inexplicably—by uncertainty and imperfect sense‐making. Coupling is the process of reflexivity‐based action for facilitating knowledge flows connecting individuals, organizations, and networks. Knowledge advantage is the art of mastering tacit corridors through the context‐sensitive application of coupling. © 2011 Wiley Periodicals, Inc.

CORRIDOR DETECTION AND TRACKING FOR VISION-BASED DRIVER ASSISTANCE SYSTEM

A significant component of driver assistance systems (DAS) is lane detection, and has been studied since the 1990s. However, improving and generalizing lane detection solutions proved to be a challenging task until recently. A (physical) lane is defined by road boundaries or various kinds of lane marks, and this is only partially applicable for modeling the space an ego-vehicle is able to drive in. This paper proposes a concept of (virtual) corridor for modeling this space. A corridor depends on information available about the motion of the ego-vehicle, as well as about the (physical) lane. This paper also suggests a modified version of Euclidean Distance Transform (EDT), named Row Orientation Distance Transform (RODT), to facilitate the detection of corridor boundary points. Then, boundary selection and road patch extension are applied as post-processing. Moreover, this paper also informs about the possible application of corridor for driver assistance. Finally, experiments using images from highways and urban roads with some challenging road situations are presented, illustrating the effectiveness of the proposed corridor detection algorithm. Comparison of lane and corridor on a public dataset is also provided.

Looking forward: translocal development in practice

This paper discusses the concepts of translocal development, development corridors and development chains, based on the insights obtained in the preceding case studies. As intermediate theoretical concepts they provide a geographical framework for understanding local development in a context of globalisation. The implications for policy include the need to give more attention to the relational dimensions of local development, complementing territorial policies with more focused management of key flows linking localities with other places.

Introduction: translocal development, development corridors and development chains

This paper offers an introduction to this Special Issue of International Development Planning Review. It uses the concepts of translocal development, development corridors and development chains to secure a better grasp of what development means in the context of globalisation and how 'local development' needs to be refined. Rather than producing transnational communities and spaces, globalisation is resulting in translocal patterns of development. Such new types of translocality will create new development opportunities, but will also restrict people's manoeuvring space to escape from poverty. The six case study empirical papers are set in this overall context and the collection is reviewed both conceptually and in the context of its implications for development planning.

Mammalian faunal dynamics in Late Pleistocene Alberta, Canada

As a conduit for the passage of faunal and human species into the New World, the much-abused concept of the so-called “ice-free corridor” has served its purpose. The corridor concept has had an important bearing on discussions of zoogeography and paved the way for hypotheses about the recolonization of North America by mammalian species from Asia. Alberta—situated along the eastern slopes of the western Cordillera adjacent to the northern Great Plains—was long considered the ideal route for Late Pleistocene migrations into the North American heartland. Yet, a temporal hiatus in the large suite of bone and wood dates from central Alberta indicates that no corridor existed during the full-glacial, from about 22 000 to 12 000 BP. DNA, isotopic, and other studies of equids, bovids, cervids, ursids, mustelids and others confirm that animals flowed through Alberta, except during full glaciation. The mid-Wisconsinan fauna in Alberta indicates movements from both south and north, reflecting the absence of ice sheets during that interval. Migrations during the Last Glacial Maximum were precluded because the Cordilleran and Laurentide ice masses had coalesced to close the corridor. Finally, with the postglacial reopening of the passage, late-surviving proboscideans, muskoxen, horses, camels and lions—facing imminent extinction—may have formed a northwesterly bound megafaunal vanguard. Simultaneously, a thriving population of moose and wapiti drove southward from Beringia towards the mid-continent.

Realities of documenting wildlife corridors in tropical countries

Connectivity is regarded as vital in conservation planning but the whereabouts of remaining wildlife corridors and dispersal areas in most tropical countries are poorly documented. With local experts, we compiled an annotated list of the most important wildlife corridors remaining on mainland Tanzania, information on the status of each corridor, wildlife using these corridors, and threats to them. We discovered that the concept of a wildlife corridor differs greatly between different people working in the same country, so we divided these into five working categories. The most common categories were those identified by known movements of animals between two protected areas, or simply proposed connections between important habitats. In Tanzania, the majority of documented corridors now seem to be in a critical condition, that is, they may have less than 5 years remaining before they disappear, judging by current rates of land use change. Five corridors are in extreme condition and could disappear within 2 years unless immediate action is taken. These pressing problems – and our experience in Tanzania – indicate that surveys of remaining wildlife corridors may need urgent documentation in other countries too and that collators should maintain loose definitions of corridors, accept data of variable quality and give information to authorities as soon as possible in order to maximize the chances of saving these conservation assets.

DEMO maintenance scenarios: Scheme for time estimations and preliminary estimates for blankets arranged in multi-module segments

The paper presents a comprehensive maintenance scheme for the multi-module segments (MMSs) blanket complete with machine concepts, logistics and flexible time estimations. The main features of this scenario are: two upper, vertically arranged maintenance ports have to be opened for blanket maintenance on opposite sides of the tokamak. The MMSs are removed and inserted through both ports which are handled in parallel and independently. Inside the vessel maximum four in-vessel machines are operating to transport the elements in toroidal direction and also to insert and attach the MMS to the shield. Outside the vessel the elements have to be transported between the tokamak and the hot cell (also with two ports) either in casks or through a corridor. For this scenario corresponding maintenance times were calculated utilizing the industrial experience of Areva NP. The paper presents preliminary time estimates for the cask scenario as well as the corridor concept, and the obtained results show good potential for a high availability reactor.

The Passage of the 1962 Commonwealth Immigrants Act, a Case-Study of Backbench Power

This article considers the concepts of corridors of power and the locus of power, within the specific context of the backbench committee structures of the House of Commons. Taking as its case study the passage of what became the 1962 Commonwealth Immigrants Act, the article considers the level of influence that should be attributed to these committees, and whether or not they should be considered as significant fora of power and influence. The committees in question are those backbench structures within the parliamentary Conservative party, principally the 1922 Committee, and the subject committees that shadow the work of government departments. While this article argues that it is indeed the case that these committees should be considered significant fora of power and influence, it proposes the notion of ‘influential impotence’ to describe the exercise of this power : while the committees are well suited to the expression of influence in general form, they often fail to translate this into power over specific policy proposals, and thus fail to realise their full potential.

Research on the thermal corridor of a hypersonic vehicle

AbstractThe establishment of a reasonable physical model and an effective solution scheme for the thermal corridor is very important to thermal protection structure design, trajectory selection, aerodynamic configuration optimization design, etc. The concept of a thermal corridor for a hypersonic vehicle was analyzed and a physical model was proposed in this paper. Furthermore, the governing equations and the corresponding algorithm for the thermal corridor were discussed. The envelopes of the height–velocity curves at typical positions of the vehicle X43 were calculated, the characteristics of the thermal corridor were summarized, the effect of the thermal protection material on the thermal corridor was discussed, and the emission coefficient of the thermal protection material was defined. The results indicate that the thermal corridor depends on the emission coefficient of the surface material, the flow conditions, and turbulence transition position. © 2008 Wiley Periodicals, Inc. Heat Trans Asian Res, 37(4): 218–223, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20203

Responses of hyporheic invertebrate assemblages to large‐scale variation in flow permanence and surface–subsurface exchange

Summary1. Flow permanence (the proportion of time that flowing water is present) strongly influences benthic invertebrate assemblages in ephemeral and intermittent river reaches. Effects of varying flow permanence on hyporheic invertebrate assemblages are not well understood, and have not previously been studied at large spatial scales.2. We used a 52‐km long flow‐permanence gradient in the alluvial Selwyn River, New Zealand to assess hyporheic assemblage responses to variation in flow permanence and surface–subsurface exchange. The Selwyn mainstem consists of perennial and temporary reaches embedded in longer downwelling (losing) and upwelling (gaining) sections.3. We predicted that hyporheic invertebrate diversity, density and assemblage stability would increase with increasing flow permanence. We further predicted that assemblage structure would be influenced by the relative contribution of downwelling and upwelling water at the reach‐scale.4. Hyporheic invertebrates were collected at 15 river cross‐sections over a 13‐month period. As predicted, hyporheic taxon richness, density and assemblage stability varied directly with flow permanence. The distribution of taxa along the flow permanence gradient appeared to be related to desiccation resistance. However, it is possible that proximity to colonist sources also contributed to distribution patterns.5. Taxon richness was significantly higher at sites in the gaining section compared with the losing section. Sites with high flow permanence in the gaining and losing sections supported distinct hyporheic assemblages, characterised by amphipods and isopods in the gaining section, and ostracods, Hydra sp. and the mayfly Deleatidium spp. in the losing section.6. Results of the study suggest an expansion of the scope of the Hyporheic Corridor Concept to include large hyporheic flowpaths associated with unbounded alluvial plains rivers. Hyporheic assemblages in alluvial rivers are strongly influenced by large‐scale flow permanence gradients, large‐scale surface water–groundwater exchange, and their interactions.

Construction and Interpretation of Model-Free Implied Volatility

The notion of model-free implied volatility (MFIV), constituting the basis for the highly publicized VIX volatility index, can be hard to measure with accuracy due to the lack of precise prices for options with strikes in the tails of the return distribution. This is reflected in practice as the VIX index is computed through a tail-truncation which renders it more compatible with the related concept of corridor implied volatility (CIV). We provide a comprehensive derivation of the CIV measure and relate it to MFIV under general assumptions. In addition, we price the various volatility contracts, and hence estimate the corresponding volatility measures, under the standard Black-Scholes model. Finally, we undertake the first empirical exploration of the CIV measures in the literature. Our results indicate that the measure can help us refine and systematize the information embedded in the derivatives markets. As such, the CIV measure may serve as a tool to facilitate empirical analysis of both volatility forecasting and volatility risk pricing across distinct future states of the world for diverse asset categories and time horizons.

Potentialities, problems, policies and progress in modelling sustainable development: A dynamic, hierarchical approach

This paper discusses some of the potentials, problems, policies and progress in modelling sustainable development. After briefly describing ten approaches to modelling sustainable development, some of the methodological problems still to be resolved are addressed. It is then suggested that policies to promote sustainable development should operate at six different spatial levels connecting global, multinational, national, regional, local and individual. Attempting to model sustainable development in such a hierarchical manner is exceedingly difficult. One way of modelling sustainable development is to develop the concept of a sustainable corridor, combining ecological, economic and equity considerations in a hierarchical fashion and through space-time. A preliminary dynamic, hierarchical model is described connecting global and national patterns of development. Using global and national data for Scotland, the calibrated model, running under the business-as-usual scenario, shows that current development paths are unsustainable. It is shown that, by implementing a judicious choice of policies, a sustainable corridor for a global and a national system can be achieved. The ways in which this preliminary model can be developed to connect all six hierarchical levels are discussed.

A review of techniques available for delimiting the erodible river corridor: a sustainable approach to managing bank erosion

AbstractTraditional policies for managing river bank erosion are currently being reconsidered as a result of increased awareness regarding the unsustainable nature of some forms of bank protection, and the role played by bank erosion in providing ecosystem services and supporting geomorphological functions. River managers are therefore increasingly seeking to preserve bank erosion within a defined erodible corridor. This paper provides an overview of the erodible corridor concept, focusing on the provision of guidelines for applying the concept in practice. We argue that a nested approach is required to address management objectives across a range of scales (network scale, reach scale, local scale) and review the different geomorphic tools that are available to help managers define the extent and inner sensitivity of the erodible corridor. These tools include simple rules of thumb such as evaluation of the equilibrium meander amplitude, historical approaches based on overlays of historical channel position, and simulation modelling. The advantages and limitations of each of these tools are discussed. Copyright © 2005 John Wiley & Sons, Ltd.

Concepts and definitions of corridors: evidence from England’s Midlands

This article reports upon some of the findings of the CORRIDESIGN research funded under the INTERREG IIC programme, focusing in particular upon the UK’s West Midlands to London corridor. This corridor can be seen as a complex area of ‘braided’ infrastructure. It reports upon the spatial dynamics of transportation, economic development, urbanisation and institutional functions of that area. The article explores some historic antecedents of corridor development; discusses the perceptions of key stakeholders in the study area; and outlines the key issues and potential policy-making building blocks that were identified. Finally the article reflects upon what the findings suggest about the concept and definition of transnational corridors between major urban agglomerations in north-west Europe. It develops Myrdal’s concepts of ‘spread’ and ‘backwash’, and of the ‘armature’ as applied to the corridor concept.

What are corridors and what are the issues? Introduction to special issue: the governance of corridors

Linear concepts such as the corridor have a long history in spatial and urban planning. The recent megacorridor or eurocorridor concept, proposed in the context of discussion on European territorial development, strives to integrate policies on infrastructure, urbanisation and economic development. As is shown by the example of the Netherlands, the corridor concept can count on a hostile reception from spatial planners. As an analytical concept the corridor can hardly be denied its legitimacy. Several urgent policy issues can be attached to corridor developments that together require an improved coordination between policy domains at different spatial levels.

Megacorridors: striking a balance between the space of flows and the space of places

The corridor concept occupies a prominent place in several European reports. The creation of corridors is related to ‘space of flows’ and ‘space of places’. The analysis of the case of the Brussels high speed train station makes it utterly clear that the space of flows often wipes out and replaces the space of places. A new financial and managerial elite is installed at the cost of the local population. This article provides elements of an alternative, open, fair and transparent approach. This calls for innovations in the governance structure as well.

Fluvial landscape ecology: addressing uniqueness within the river discontinuum

1. As rivers and streams are patchy and strongly hierarchical systems, a hierarchical patch dynamics perspective can be used as a framework for visualising interactions between structure and function in fluvial landscapes. The perspective is useful for addressing fundamental attributes of lotic ecosystems, such as heterogeneity, hierarchy, directionality and process feedback occurring across spatial scales and for illustrating spatio‐temporal linkages between disparate concepts in lotic system ecology such as the River Continuum Concept, the Serial Discontinuity Concept, the Flood Pulse Concept and the Hyporheic Corridor Concept.2. At coarse spatial scales, the hierarchical patch dynamics perspective describes each river network as a unique, patchy discontinuum from headwaters to mouth. The discontinuum is comprised of a longitudinal series of alternating stream segments with different geomorphological structures. Each confluence in the steam network further punctuates the discontinuum because the sudden change in stream characteristics can create a `gap' in the expected pattern of downstream transitions. The discontinuum view recognises general trends in habitat characteristics along the longitudinal profile, but creates a framework for studying and understanding the ecological importance of each stream's individual pattern of habitat transitions along longitudinal, lateral or vertical vectors at any scale.3. Object‐oriented modelling and programming techniques provide a means for developing robust, quantitative simulation models that describe the dynamic structure of patch hierarchies. Such models can simulate how the structure and function of lotic ecosystems are influenced by the landscape context of the system (the ecological conditions within which the system is set) and the metastructure (structural characteristics and juxtaposition) of finer‐scale patches comprising the system.4. A simple object‐oriented, multiscale, discontinuum model of solute transformation and biological response along a stream channel illustrates how changing the branching pattern of a stream and the arrangement of its component patches along the downstream profile will result in substantial changes in predicted patterns of solute concentration and biotic community structure.5. The importance of context, structure, and metastructure in determining lotic ecosystem function serves to underscore Hynes' (1975) concept that `every stream is likely to be individual.' Advancing the discipline of fluvial landscape ecology provides an excellent opportunity to develop general concepts and tools that address the individual character of each stream network and integrate the concept of `uniqueness within the river discontinuum' into our ecological understanding of rivers and streams.

Geomorphic process-disturbance corridors: a variation on a principle of landscape ecology

The paradigm of landscape ecology describes a landscape as a mosaic of landscape elements including the matrix, patches and corridors. Corridors are described as linear disruptions to the matrix, produced by anthropogenic actions or by streams which produce riparian corridors. Snow avalanches and debris flows are other geomorphic processes that should be considered as geomorphic process corridors rather than as disturbance patches. They possess requisite linearity, and they accomplish the five functions of a corridor: habitat, conduit, filter, source and sink. The definition of corridor in landscape ecology should be modified to embrace the concept of geomorphic process corridors.