Provision of reserve capacity on the Nordic electricity market: Principles and practises

System reliability is a key aspect of electricity supply, and the ability to maintain system reliability thus is an important aspect of a liberalised electricity market. But system reliability can be ensured only if there is sufficient reserve capacity at all times. In a liberalised electricity market the provision of reserve capacity is a matter of incentives. The Nordic electricity market, comprising of the integrated Danish, Finnish, Norwegian and Swedish electricity markets, has worked well from a system reliability point of view. A key factor behind this favourable outcome is that the incentives for keeping sufficient reserve capacity have been strong enough. The reason for this is an adequate institutional design point. More precisely the set of markets that is commonly called “the electricity market” includes both regulation and capacity markets, and rules and regulations are such that these markets are wellfunctioning.Nordic electricity market; reserve capacity; peak capacity; capacity market.

Identification of the process damping coefficient in dry and wet machining of steel

Flank face chamfers are an effective way to suppress vibrations and increase the productivity of milling processes. The underlying process damping mechanism is the so-called indentation effect. The effect describes the process damping as a result of an additional force due to the indentation of workpiece material under the flank face. In literature, this force is commonly modeled by the volume indented under the flank face and a process damping coefficient. To determine the process damping coefficient, various approaches with partly contradictory results exist. In this paper, a novel method to calculate the process damping coefficient based on process forces measurements in orthogonal cutting is applied for steel machining. The method considers ploughing effects of flank face chamfer and cutting edge rounding as well as plastic deformation effects. In the current investigation, the approach is applied to different cooling strategies, chamfer widths, and cutting speeds. The results show that the cutting speed has the most significant influence on the process damping coefficient. With increasing cutting speed, the process damping coefficient increases, which can be attributed to strain rate hardening effects

Marine Debris Floating in Arctic and Temperate Northeast Atlantic Waters

Floating marine debris is ubiquitous in marine environments but knowledge about quantities in remote regions is still limited. Here, we present the results of an extensive survey of floating marine debris by experts, trained scientists from fields other than pollution or non-professional citizen scientists. A total of 276 visual ship-based surveys were conducted between 2015 and 2020 in the Northeast (NE) Atlantic from waters off the Iberian Peninsula to the Central Arctic, however, with a focus on Arctic waters. Spatiotemporal variations among regional seas (Central Arctic, Barents Sea, Greenland Sea, Norwegian Sea, North Sea) and oceanic regions (Arctic waters and the temperate NE Atlantic) were explored. The overall median debris concentration was 11 items km-2, with considerable variability. The median concentration was highest in the North Sea with 19 items km-2. The Nordic seas, except the Central Arctic showed median concentrations ranging from 9 to 13 items km-2. Plastic accounted for 91% of all floating items. Miscellaneous fragments, films, ropes and nets, packaging materials, expanded polystyrene and straps were the most frequently observed plastic types. Although the median debris concentration in the Central Arctic was zero, this region was not entirely free of floating debris. The variations between regional seas and oceanic regions were statistically not significant indicating a continuous supply by a northward transportation of floating debris. The data show a slight annual decrease and clear seasonal differences in debris concentrations with higher levels observed during summer. A correlation between debris concentrations and environmental and spatial variables was found, explaining partly the variability in the observations. Pollution levels were 500 times lower than those recorded on the seafloor indicating the seafloor as a sink for marine debris. The Arctic was characterised by similar pollution levels as regions in temperate latitudes highlighting that Arctic ecosystems face threats from plastic pollution, which add to the effects of rapid climate change

Citizen scientists reveal: marine litter pollutes Arctic beaches and affects wild life

Recent data indicate accumulation areas of marine litter in Arctic waters and significant increases over time. Beaches on remote Arctic islands may be sinks for marine litter and reflect pollution levels of the surrounding waters particularly well. We provide the first quantitative data from surveys carried out by citizen scientists on six beaches of Svalbard. Litter quantities recorded by cruise tourists varied from 9-524 g m-2 and were similar to those from densely populated areas. Plastics accounted for >80% of the overall litter, most of which originated from fisheries. Photographs provided by citizens show deleterious effects of beach litter on Arctic wildlife, which is already under strong pressure from global climate change. Our study highlights the potential of citizen scientists to provide scientifically valuable data on the pollution of sensitive remote ecosystems. The results stress once more that current legislative frameworks are insufficient to tackle the pollution of Arctic ecosystems

Tackling Marine Litter - LITTERBASE

Anthropogenic litter contamination of the oceans is a global problem of growing concern and currently receives strongly increasing attention by policy makers, public authorities, media and the general public. Unlike many other pollutants, marine litter on beaches and its deleterious effects on marine mammals, birds and turtles have attracted much attention as they can be directly observed by stakeholders

LITTERBASE - Online Portal for Marine Litter & Microplastics and their Implications for Marine Life

Contamination of the oceans with anthropogenic litter is a global environmental problem which currently receives increasing attention by scientists, policy makers, public authorities, media and the general public. Although research efforts have been intensified, they often do not provide stakeholders with easily understandable information about the dimensions and the extent of the problem. We have developed an online portal to provide easily digestible and continuously updated information on marine litter and microplastics to stakeholders based on scientific literature on a global scale. LITTERBASE gives insight about the distribution of marine litter and its effects on marine biota. Data from 1,420 scientific studies (status 09/10/2017) have been compiled into global maps and real-time graphs to make scientific knowledge accessible to the public. Bibliometric data of all publications were entered, as were metadata pertaining to litter type, litter size, litter quantity unit, aquatic system, biome and total litter quantity. Litter quantities were standardised to the most frequently used units to achieve comparability. Data on biological interactions with litter were also extracted: location of field records, number of species affected, percentage of individuals affected, type of interaction, effects on biota, litter type, litter size, aquatic system and biome. Currently, 1,441 species (status 09/10/2017) have been found to interact with marine litter resulting in mortality in almost 20% of the cases. Web statistics reveal that the information displayed in the LITTERBASE online portal is continuously being retrieved by users from all over the world

Cyst Features and Risk of Malignancy in Intraductal Papillary Mucinous Neoplasms of the Pancreas: Imaging and Pathology

Background: Intraductal papillary mucinous neoplasms (IPMNs) display diverse macroscopic, histological, and immunohistochemical characteristics with typical morphological appearance in magnetic resonance imaging. Depending on those, IPMNs may show progression into invasive carcinomas with variable frequency. Overall, IPMN-associated invasive carcinomas are found in about 30% of all IPMNs, revealing phenotpyes comparable with conventional ductal adenocarcinomas or mucinous (colloid) carcinomas of the pancreas. In Sendai-negative side-branch IPMNs, however, the annual risk of the development of invasive cancer is 2%; thus, risk stratification with regard to imaging and preoperative biomarkers and cytology is mandatory. Methods and Results: The present study addresses the radiological and interventional preoperative measures including histological features to determine the risk of malignancy and the prognosis of IPMNs. Conclusion: While preoperative imaging largely relies on the detection of macroscopic features of IPMNs, which are associated with a divergent risk of malignant behavior, in resected specimens the determination of the grade of dysplasia and the detection of an invasive component are the most important features to estimate the prognosis of IPMNs

Age/disease duration influence on activities of daily living and quality of life after levodopa-carbidopa intestinal gel in Parkinson's disease

Aim: To determine if age and Parkinson's disease duration at therapy initiation influence the efficacy of levodopa-carbidopa intestinal gel (LCIG) on quality of life and activities of daily living. Patients & methods: This post hoc analysis assessed subgroups of patients stratified by baseline age, disease duration, hours/day of 'off' time and levodopa equivalent dose. Patients' data were collected from the GLORIA study, a 24-month observational registry evaluating long-term effectiveness of LCIG. Results & conclusion: LCIG therapy led to sustained improvements in quality of life irrespective of patient age and disease duration at baseline. Improvements in activities of daily living were observed across all subgroups, particularly in younger patients, patients with shorter disease duration and in patients with the highest baseline levodopa equivalent dose

Анализ и интерпретация гидродинамических исследований для двухфазного потока (вода-нефть)

Показаны проблемы, возникающие при интерпретации и анализе данных гидродинамических исследований, проведенных на скважинах с обводненностью, отличной от нуля. Разобраны преимущества и недостатки применяемых методов интерпретации и анализа. Представлен новый метод нормализации подвижности для анализа результатов гидродинамических исследований скважин