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In view of the advantages and shortcomings of the watershed algorithm in the image segmentation, this paper has given an improved vicent watershed algorithm, and used the dynamic particle clustering with connectivity constraints to combine regions after initial segmentation. It effectively solves the over-segmentation problem arising from the watershed algorithm. [ABSTRACT FROM AUTHOR]

In this study we compared the biodiversity of five waterbody types (ditches, lakes, ponds, rivers and streams) within an agricultural study area in lowland England to assess their relative contribution to the plant and macroinvertebrate species richness and rarity of the region. We used a Geographical Information System (GIS) to compare the catchment areas and landuse composition for each of these waterbody types to assess the feasibility of deintensifying land to levels identified in the literature as acceptable for aquatic biota. Ponds supported the highest number of species and had the highest index of species rarity across the study area. Catchment areas associated with the different waterbody types differed significantly, with rivers having the largest average catchment sizes and ponds the smallest. The important contribution made to regional aquatic biodiversity by small waterbodies and in particular ponds, combined with their characteristically small catchment areas, means that they are amongst the most valuable, and potentially amongst the easiest, of waterbody types to protect. Given the limited area of land that may be available for the protection of aquatic biodiversity in agricultural landscapes, the deintensification of such small catchments (which can be termed microcatchments) could be an important addition to the measures used to protect aquatic biodiversity, enabling `pockets΄ of high aquatic biodiversity to occur within working agricultural landscapes. [ABSTRACT FROM AUTHOR]

Precise statistics play a key role in the management of systems and processes. For instance, having knowledge about size distribution of stone fragments in a mining factory can allow suitable choosing of the diameter of a sieve or designing of a better crusher, hence optimizing the production line. This paper describes and compares three image-based techniques that statistically estimate stone size distribution. The techniques are watershed, granulometry and area boundary. Results show that in many mining stone factories due to identical stone texture, granulometry is a good replacement for edge detection based methods. An important point about granulometry is that its results are very qualitative; it cannot determine the exact number of stone fragments, but it can superlatively distinguish size distribution of objects in real images including objects with different textures, disparity and overlapping. [ABSTRACT FROM AUTHOR]

An automatic lips detection and tracking system based on watershed segmentation and H∞ approach is presented. For some of the lips detection systems, skin/non-skin detection is a prerequisite step to localise the face region and the lips region is then detected from the face region. In this paper, a direct lips detection technique using watershed segmentation without needing preliminary face localisation is proposed. The watershed algorithm segments the input image into regions. Consequently, the cubic spline interpolant lips colour modelling and symmetry detection are used to detect the lips region from the segmented regions. The position of the segmented lips is passed to the H∞ tracking system to predict the location of the lips in the succeeding video frame. The simulation results have revealed a good performance of the proposed method. [ABSTRACT FROM AUTHOR]

Geographical Information Systems (GIS) and Digital Elevation Models (DEM) can be used to perform many geospatial and hydrological modelling including drainage and watershed delineation, flood prediction and physical development studies of urban and rural settlements. This paper explores the use of contour data and planimetric features extracted from topographic maps to derive digital elevation models (DEMs) for watershed delineation and flood impact analysis (for emergency preparedness) of part of Accra, Ghana in a GIS environment. In the study two categories of DEMs were developed with 5 m contour and planimetric topographic data; bare earth DEM and built environment DEM. These derived DEMs were used as terrain inputs for performing spatial analysis and obtaining derivative products. The generated DEMs were used to delineate drainage patterns and watershed of the study area using ArcGIS desktop and its ArcHydro extension tool from Environmental Systems Research Institute (ESRI). A vector-based approach was used to derive inundation areas at various flood levels. The DEM of built-up areas was used as inputs for determining properties which will be inundated in a flood event and subsequently generating flood inundation maps. The resulting inundation maps show that about 80% areas which have perennially experienced extensive flooding in the city falls within the predicted flood extent. This approach can therefore provide a simplified means of predicting the extent of inundation during flood events for emergency action especially in less developed economies where sophisticated technologies and expertise are hard to come by. [ABSTRACT FROM AUTHOR]

The paper deals with assessment of the existing storm sewer system of the Prishtina airport area in Kosovo. Frequent flooding of the airport area occurred recently and the activities in flood assessment and flood protection design were undertaken. First step in achieving flood risk assessment is data collection. Since the region recently was in war conflict it was not an easy task to obtain necessary data. Availability, suitability and quality of hydrological, meteorological, topographic and management data is discussed. Some results obtained by hydrological analysis of the maximum runoff flows with different probability, as well as the results obtained by hydraulic modeling of the existing drainage system are presented. Flood risk maps have been created, flood risk analysis was preformed and measures against flooding of the runway were proposed. Furthermore, the importance of applying proper methodologies in flood analysis in storm sewer systems is also discussed. Maintenance of the existing system and establishing early warning, prediction and forecasting is extremely important in evaluating flood risk assessment and flood risk management. [ABSTRACT FROM AUTHOR]

This work is settled in the framework of abstract simplicial complexes. We propose a definition of a watershed and of a collapse for maps defined on pseudomanifolds of arbitrary dimension. Through an equivalence theorem, we establish a deep link between these two notions: any watershed can be obtained by collapse iterated until idempotence, and conversely any collapse iterated until idempotence induces a watershed. We also state an equivalence result which links the notions of a watershed and of a collapse with the one of a minimum spanning forest. [ABSTRACT FROM AUTHOR]

In this paper, an adjustable processing window based on lips-skin ratio is proposed to enhance the lips detection and tracking algorithm presented in [1]. The algorithm suggested in [1] is only working well if the tracked subject is moving horizontally with the same lips size. The fixed small window is failed to be used to capture the whole lips region which gradually increased when the subject moves towards the detection device. In this paper, a lips-skin ratio is keep tracked to ensure that in every small window, the entire lips region is properly encircled which a certain skin region. If the obtained ratio is greater than the threshold, means the lips region has exited the window; the size of window is hence adjusted till it satisfies the threshold value. The proposed approach is adapted into [1] and the simulation results have manifested an improvement of the overall watershed lips segmentation and detection system. [ABSTRACT FROM AUTHOR]

This paper presents distinctive features, total usage, and the potential of water resources of Azerbaijan. The agreements on use of water resources of the transboundary rivers are described and characterized. Rational use and protection of transboundary water resources require specific actions. [ABSTRACT FROM AUTHOR]

Presented overview of Russian system of water management contains information on history of water accounting system, existed legislative issues and system of water basin districts and administrations, statistics on water consumption in the Russian Federation (1970–1998). Water use at the regional level and transboundary use of water resources are illustrated by example of the Kaliningrad Oblast, an enclave Russian territory in the South-East Baltic. Overlapped structure of boundaries of administrative units and watersheds is a basis for downscaling of transboundary issues till the level of local municipalities. Some basic statistics on water consumption, information on price for water use as well as on responsibilities of local water administration are given. [ABSTRACT FROM AUTHOR]

Sustainable use and development of watersheds become a major target of the national, European and global strategies and policies for sustainable development. This is based on recognition that: (i) the lotic and lentic systems are major components of the biophysical structure of natural capital which play a key role in providing a wide range of resources (e.g. water, food resources) and services (e.g. flood detention, recharging and discharging aquifers; nutrient retention and release, trace elements retention); (ii) the structure, water quality and their functions – production, regulation, information and support – were modified and degraded, in all EU countries (including Romania) in a proportion ranging between 50–90% (Castro et al., 2002; Nivet and Frazier, 2004; Revenga and Kura, 2003; Vadineanu et al., 2003); (iii) the water quality and the integrity or health of the lotic and lentic ecosystems are the results of long term integration of the cumulated stress of both human and natural pressures, acting at the watershed scales; (iv) there is a need to shift the former sectoral and reductionistic based management of water resources towards integrated/or ecosystem and adaptive management at the catchment scale (EU-WFD) and; (v) the management plans and decisions for sustainable use and development of watersheds have to rely on evaluation – in physical and monetary terms – of the impact of human pressures upon the water ecosystems structure and functions and, the quality and density of resources and services flows. Taking into consideration the above guiding requirements and the major social, political and economic changes emerged during more than 16 years of transition and negotiation of the EU accession and integration, the presentation is focused on the current status of the new emerging institutional, governing, legislative and administrative frameworks. A particular attention will be given to: (i) the 11 administrative units (hydrologie basins and watersheds) which cover the river network at the national scale; (ii) land use and landscape structure; (iii) water course management; (iv) major drivers and pressures impacting on water quality and water ecosystem health; (v) first classification of ˵water bodies″ and assessment of their ˵ecological status″; (vi) former economic analysis and new requirements for ˵environmental and resource cost and benefit analysis″; (vii) the current institutional framework including stakeholders network and their involvement; and to many difficulties the EU–WFD implementation process is facing as well as major emerging water policy issues and risks. [ABSTRACT FROM AUTHOR]

This paper presents a novel texture segmentation scheme based on two techniques: watershed and a novel structural adaptation artificial immune antibody competitive network (SAIANet). The proposed scheme first partitions image into a set of regions by watershed algorithm and then clusters the watershed regions by SAIANet, where the gray level co-occurrence matrix and the wavelet frame texture features are extracted from each watershed region as the antigens of SAIANet. A new immune antibody neighborhood and an adaptive learning coefficient are presented, and inspired by the long-term memory in cerebral cortices, a long-term memory coefficient is introduced into the network. The minimal spanning tree in graph theory is used to automatically cluster antibody obtained in the output space without a predefined number of clustering. Finally, the presented SAIANet is devoted to performing a fully unsupervised texture segmentation with a superior performance, which makes full use of the watershed segmentation results. [ABSTRACT FROM AUTHOR]

North of the equator It has become a truism of historical writing to conceive of Africa in the course of the nineteenth century as becoming increasingly a part of, and a product of, the expansion of Europe, which, beginning in the fifteenth and sixteenth centuries, had integrated ever larger areas of the world into a single economic system. In attempting an overview of the state of the continent on the eve of partition – roughly over the decade of the 1870s – a large number of questions arise from a consideration of this truism. To what extent was Africa already an adjunct of an economic system dominated by Europe? What was the relationship between Africa and this European system – was it one of an equal or an unequal exchange of commodities? To what extent was Africa dependent economically, if not yet politically? What social and ideological changes were beginning to follow from this dependency? Was Africa a fruit ripe for plucking in the 1870s, was there a certain inevitability about the forthcoming imperialist carve-up, or was partition an extraneous historical occurrence forced upon a continent which had within it other options for coping with the future? There are no answers to these questions that are at the same time simple and sensible. Certainly the answers to all such queries will differ, according to the region of Africa which is under scrutiny. Even within particular regions, the situation of individual states, societies or groups of people, their relations with each other and with the outside world (especially with the European capitalist economies) varied greatly. [ABSTRACT FROM AUTHOR]