Search results for "Stream"
showing 10 items of 682 documents
New-stage discharge relationships for free and submerged sluice gates
2012
Abstract The flow movement through a sluice gate is investigated for both free and submerged flow conditions. For free flow condition, the current dimensionless formula, indicated acceptable accuracy; while for submerged flow condition it was modified especially for low submerged condition. In this regard, Buckingham theorem along with the Incomplete Self-Similarity concept was employed and a new stage–discharge relationship was developed accordingly. Also, to achieve a suitable formula for submerged flow condition being accurate in low submergence, the maximum tailwater depth allowing the free flow condition and head loss factor were identified as missing parameters in the functional dimen…
A review of hydropower plants in Romania: Distribution, current knowledge, and their effects on fish in headwater streams
2021
Abstract Hydropower is currently experiencing a boom in southeast Europe. For Romania, the number of hydropower plants is estimated to be between 545 and 674, but little has been published about their environmental impact. We provide the first overview of the geographical distribution of hydropower plants in Romania, supplemented by a review of current knowledge about their environmental impact, and present case study evidence on the effects of small hydropower plants on fish in headwater streams of the Carpathian Mountains. We show that 49% of the documented 545 hydropower plants in Romania are located in Natura 2000 or other protected areas, 5% are located in water bodies with ‘very good’…
Selecting a small run-of-river hydropower plan by the analytic hierarchy process (AHP): A case study of Miño-Sil river basin, Spain
2015
Hydroelectric power is obtained by harnessing the potential energy of a mass of water flowing along a river bed to convert it first into mechanical and then into electrical energy. The system is therefore both clean and autonomous and has a high potential for development. A small hydropower plant has an installed power capacity of below 10 MW and is considered run-of-river when it diverts part of a river flow to generate its electricity. The use of multicriteria techniques in environmental decision making, including selecting between various alternatives, is important when it involves complex decisions in a number of disciplinary fields. The most widely used of these techniques is the analy…
Digitalized bioeconomy: Planned obsolescence-driven circular economy enabled by Co-Evolutionary coupling
2019
Driven by digital solutions, the bioeconomy is taking major steps forward in recent years toward achievement of the long-lasting goal of transition from a traditional fossil economy to a bioeconomy-based circular economy. The coupling of digitalization and bioeconomy is leading towards a digitalized bioeconomy that can satisfy the shift in consumers’ preferences for eco-consciousness, which in turn induces coupling of up-down stream operation in the value chain. Thus, the co-evolution of the coupling of digitalization and bioeconomy and of upstream and downstream operations is transforming the forest-based bioeconomy into a digital platform industry. Aiming at addressing this transformation…
Sports, morality and body: the voices of sportswomen under Franco's dictatorship
2016
The aim of this research is to study sportswomen’s perceptions and experiences of women’s sport in Francoist Spain (1939–1975). The main objective is to analyse the social, moral and aesthetic elements that are present in the experience of these athletes. This study was carried out with an intentional sample of 24 women from Andalusia, Aragon, Asturias, Basque Country, Catalonia and Valencia. They were interviewed by a network of researchers from six universities. Outstanding results show the existence of social limitations to start sports practice (particularly in the post-war period); the importance of sport as a character-building aspect; sport’s remarkable influence on their body self-c…
Experimental modeling for a natural landing of fuzzy sets in new domains
2015
In this paper we plan to touch upon (and briefly discuss) some (out of the many) contributions done by Enric Trillas to Fuzzy Sets Theory. We have carefully chosen, from the abundant panorama we have been allowed to gaze at in the years, two different but intertwined topics of a more methodological character, which—as such—are, obviously, not only outside the topics massively developed by the scientific community in this field but also not in the mainstream of Enric’s investigations. We picked up them, however, since we believe that they are related to a crucial problem for the further developments of fuzzy research in the subsequent years. In this perspective, they represent a very signifi…
LA VIABILITÀ MINORE NELLA SICILIA CENTRO-MERIDIONALE: IL COMPRENSORIO DI CIGNANA TRA LA VIA SELINUNTINA E LA CATINA-AGRIGENTUM
2021
Obiettivo del contributo è esaminare il sistema stradale di età antica, con un’attenzione particolare rivolta alle vie secondarie, in un ben definito comprensorio della Sicilia meridionale, l’area del Progetto Cignana, pochi km ad est di Agrigento. Si tratta di cogliere non tanto i caratteri della viabilità di lunga percorrenza (la via Selinuntina e la via Catina-Agrigentum) quanto piuttosto le interconnessioni tra i principali assi viari, la rete secondaria (spesso attestata lungo i principali corsi d’acqua), gli insediamenti rurali e gli approdi sulla costa. This paper is aimed to analyze the ancient road system in a selected area of the Southern Sicily, between Agrigento and Licata (Cign…
Online Principal Component Analysis in High Dimension: Which Algorithm to Choose?
2017
Summary Principal component analysis (PCA) is a method of choice for dimension reduction. In the current context of data explosion, online techniques that do not require storing all data in memory are indispensable to perform the PCA of streaming data and/or massive data. Despite the wide availability of recursive algorithms that can efficiently update the PCA when new data are observed, the literature offers little guidance on how to select a suitable algorithm for a given application. This paper reviews the main approaches to online PCA, namely, perturbation techniques, incremental methods and stochastic optimisation, and compares the most widely employed techniques in terms statistical a…
Forest drainage: a threat to benthic biodiversity of boreal headwater streams?
1998
1. Forest drainage, including mainly ditching of waterlogged peatlands in order to increase wood growth, has caused substantial changes in the hydrology and water quality of Finnish streams. However, knowledge on the ecological impact of these changes is poor. This paper studies the potential impact of forest drainage, catchment characteristics and habitat factors on the water quality and benthic macroinvertebrates in headwater streams of the River Isojoki, western Finland. An intensive programme of water sampling was carried out at nine study sites, while zoobenthic samples covered a total of 18 streams. 2. According to multivariate regression models concentrations of aluminium and suspend…
Changes in habitat structure, benthic invertebrate diversity, trout populations and ecosystem processes in restored forest streams: a boreal perspect…
2007
SUMMARY 1. Most Finnish streams were channelised during the 19th and 20th century to facilitate timber floating. By the late 1970s, extensive programmes were initiated to restore these degraded streams. The responses of fish populations to restoration have been little studied, however, and monitoring of other stream biota has been negligible. In this paper, we review results from a set of studies on the effects of stream restoration on habitat structure, brown trout populations, benthic macroinvertebrates and leaf retention. 2. In general, restoration greatly increased stream bed heterogeneity. The cover of mosses in channelised streams was close to that of unmodified reference sites, but a…