Going Underground at the Selected Site for Site Confirmation

2001 ◽  
Author(s):  
Timo Äikäs
Keyword(s):  
Second Step ◽  
Spent Fuel ◽  
Detailed Design ◽  
Disposal Facility ◽  
Continuous Activity ◽  
A Site ◽  
Whole Life Cycle ◽  
New Phase ◽  
Selection Of

Abstract The long-term programme aimed at selection of a site for a deep repository was initiated in Finland in 1983. This programme has come to end and a new phase aimed at implementation of the geological disposal of spent fuel has been started. In this new phase the first milestone is the application for a construction license for the disposal facility around 2010 and thereafter, as a second step, the operation license in 2020. To fulfil the needs for detailed design of the disposal system, an underground rock characterisation facility, “ONKALO”, will be constructed at the representative depth at Olkiluoto. The excavation of this facility will start the work for underground characterisation, testing and demonstration which is planned to be a continuous activity throughout the whole life cycle of the deep repository.

scholarly journals Preliminary modelling of radionuclide migration in the argillaceous sediments of the Sumer Formation (Northwestern Bulgaria)

2020 ◽  
Vol 49 (3) ◽  
pp. 13-18
Author(s):  
Dimitar Antonov ◽  
Madlena Tsvetkova ◽  
Doncho Karastanev
Keyword(s):  
Radioactive Waste Disposal ◽  
High Level Waste ◽  
Spent Fuel ◽  
Radionuclide Migration ◽  
Geological Disposal ◽  
Disposal Facility ◽  
Deep Geological Disposal ◽  
High Level ◽  
Host Rocks ◽  
Selection Of

In Bulgaria, from the preliminary analyses performed for site selection of deep geological disposal of high-level waste (HLW) and spent fuel (SF), it was concluded that the most promising host rocks are the argillaceous sediments of the Sumer Formation (Lower Cretaceous), situated in the Western Fore-Balkan Mts. The present paper aims to compare the transport of three major radionuclides from a hypothetical radioactive waste disposal facility, which incorporates an engineering barrier of bentonite into the argillaceous (marl) medium. The simulations were performed by using HYDRUS-1D computer programme. The results are used for a preliminary estimation of argillaceous sediments as a host rock for geological disposal of HLW.

Gulf of Mexico Hurricane Single Event Fatigue Method for Riser Analysis

2020 ◽  
Author(s):  
Jose D. Mesa ◽  
Markku J. Santala
Keyword(s):  
Gulf Of Mexico ◽  
Fatigue Damage ◽  
Full Range ◽  
Single Event ◽  
Extreme Loads ◽  
Simplified Method ◽  
Steel Catenary Risers ◽  
A Site ◽  
Selection Of

Abstract Deepwater steel catenary risers (SCRs) are designed considering strength under extreme loads and long-term fatigue of the riser from installation through the full range of conditions anticipated over the service life of the riser. Short-term single event fatigue is also checked to ensure that a single extreme storm or current event does not consume an excessive amount of fatigue capacity. For Gulf of Mexico SCRs, single event fatigue can be a governing case for the riser hang-off. The requirement imposes a relatively modest number of higher stress range cycles and may bias the selection of the hang-off option (titanium, steel, and flex joints) since the three common choices have widely different sensitivity to this case. Assessing a single event hurricane is problematic because the evolution of storms which generate an extreme 100-year significant wave height at a site can vary considerably from storm-to-storm. Simplistic representations of the extreme hurricane event could lead to either non-optimal hang-off option or a unconservative design. This study documents a response-based analysis simulating fatigue damage accumulated in differing risers over a broad set of extreme hurricanes. The extreme hurricanes are gathered from hundreds of years of hindcast storms to develop a statistical assessment of the amount of damage accumulated per event. Since the response-based analysis would be cumbersome in the design process, a simplified method benchmarked to the response-based analysis is proposed for design. The simplified method consists of accumulating fatigue damage from multiple seastate cases that are already developed to assess riser strength.

Framework for an environmental safety case for geological disposal in the UK

2012 ◽  
Vol 76 (8) ◽  
pp. 3457-3464 ◽  
Author(s):  
M. J. Poole ◽  
R. Kowe
Keyword(s):  
Environmental Safety ◽  
Approval Process ◽  
Site Specific ◽  
Geological Disposal ◽  
Disposal Facility ◽  
Safety Case ◽  
The Uk ◽  
A Site

AbstractThe implementation of a geological disposal facility requires the demonstration of confidence that such a facility would be safe during both the operational period and in the long-term after the closure of such a facility. The generic environmental safety case described in this paper is the vehicle used to demonstrate an understanding of environmental safety. It will be used to prepare a site-specific environmental safety case in due course. The approach taken will be consistent with a staged development and approval process, as advocated by the environmental regulators.

Decommissioning Strategy Options for MR Reactor at the Kurchatov Institute, Moscow

2007 ◽  
Author(s):  
M. T. Cross ◽  
N. F. Harman ◽  
D. Charles ◽  
A. Harper ◽  
B. K. Bylkin ◽  
...  
Keyword(s):  
Reactor Power ◽  
Materials Testing ◽  
Spent Fuel ◽  
Kurchatov Institute ◽  
Attribute Analysis ◽  
Fuel Reactor ◽  
Contamination Levels ◽  
Selection Of

The principal decommissioning goal for the nuclear installations of the Kurchatov Institute is the removal of spent fuel, reactor facilities and radioactive waste from the Institute’s site. As the result of decommissioning, the buildings, constructions and areas should be cleaned to residual contamination levels acceptable to the stakeholders. These levels are determined in view of possible options for the rehabilitation of the Institute’s areas under conditions of compliance with acting legislation for safety provisions for staff, population noting the proximity of the site to the local urban environment. Research reactor MR was commissioned in 1963 for reactor materials testing and finally shutdown in 1993. The reactor power with the experimental loops was 50 MWt. Several features were identified for the development of a decommissioning strategy for this reactor, namely: – the strategy should consider many factors in a broad approach with international, inter-industry and long-term perspectives; – the current situation for decommissioning is uncertain and must account for the views of a variety of stakeholders on possible final conditions and further use of the site and the route to achieve these; and – a lack of sufficiency in the national legislation base for execution of the work and the possible options for its completion. On the basis of worldwide experience, the strategy for decommissioning of reactor MR was determined as follows: – determination of the options for the final rehabilitation of the Institute’s areas; – determination of the stakeholders and their priority concerns; – determination of the strategy options for achievement of the final status; – determination of the main factors influencing the selection of the decommissioning strategy; – selection of the most acceptable strategies on the basis of a multi-attribute analysis; – determination of the main stages and principles of implementation of the selected strategy; and – development of the decommissioning activities considering the work that will be required. As the result of the multi-attribute analysis, the following conclusion has been made: – the preferred final status of the facility is for a nuclear re-use application; – the preferred decommissioning option is immediate dismantling.

Women's Participation in Politics: Ukrainian Case

2014 ◽  
Vol 2013 (3) ◽  
pp. 53-66
Author(s):  
Skovikov Alexey
Keyword(s):  
Political Culture ◽  
Separation Of Powers ◽  
Party Competition ◽  
Political Life ◽  
Ruling Class ◽  
Political Actors ◽  
Women's Participation ◽  
Democratic Transformation ◽  
Selection Of

AbstractThe international practices takes into account the question of women's participation in the political life of modern Ukraine. The selection of the state was due to the dynamic process of democratic transformation - the separation of powers, the formation of multi-party competition among political actors in the electoral process, the activity women in the various institutions of civil society. The position was claimed on the basis of empirical data range of academic institutions and reputable sociological centers, and also interviews with experts who said that the creation of real conditions for self-realization by women's interest in politics is only possible for long term. The process is controversial and caused by political culture, traditions and interests of the ruling class represented mainly by men.

Evidence for a single mechanism gating perceptual and long-term memory information into working memory

2020 ◽  
Author(s):  
Sam Verschooren ◽  
Yoav Kessler ◽  
Tobias Egner
Keyword(s):  
Working Memory ◽  
Long Term Memory ◽  
Sources Of Information ◽  
Term Memory ◽  
Source Selection ◽  
Single Mechanism ◽  
Gating Mechanism ◽  
Opening And Closing ◽  
Selection Of

An influential view of working memory (WM) holds that its’ contents are controlled by a selective gating mechanism that allows for relevant perceptual information to enter WM when opened, but shields WM contents from interference when closed. In support of this idea, prior studies using the reference-back paradigm have established behavioral costs for opening and closing the gate between perception and WM. WM also frequently requires input from long-term memory (LTM), but it is currently unknown whether a similar gate controls the selection of LTM representations into WM, and how WM gating of perceptual vs. LTM sources of information relate to each other. To address these key theoretical questions, we devised a novel version of the reference-back paradigm, where participants switched between gating perceptual and LTM information into WM. We observed clear evidence for gate opening and closing costs in both cases. Moreover, the pattern of costs associated with gating and source-switching indicated that perceptual and LTM information is gated into WM via a single gate, and rely on a shared source-selection mechanism. These findings extend current models of WM gating to encompass LTM information, and outline a new functional WM architecture.

scholarly journals A Multi-Attribute Decision Method under Uncertainty Environment Conditions—The Green Supplier Evaluation Perspective

2021 ◽  
Vol 18 (1) ◽  
pp. 344
Author(s):  
Hao Xu ◽  
Liuxin Chen ◽  
Qiongfang Li ◽  
Jianchao Yang
Keyword(s):  
Environmental Pollution ◽  
Evaluation Method ◽  
External Environment ◽  
Environmental Indicators ◽  
Supplier Evaluation ◽  
Uncertain Environment ◽  
Green Suppliers ◽  
Uncertainty Environment ◽  
Selection Of

Due to the continuous changes of political environment, consumption habits, technological progress and other factors, the external environment of enterprises is full of uncertainty. The turbulence of external environment is not conducive to the long-term operation and development of enterprises, but also brings great challenges to the selection of suppliers. This makes the competition of enterprises focus on how to choose long-term cooperation suppliers in the uncertain external environment. In addition, due to the deterioration of the global environment, governments pay more and more attention to environmental pollution, and consumers are more and more inclined to green consumption, which makes many companies pay more and more attention to environmental indicators when selecting suppliers. In the case of external environment turbulence and serious environmental pollution, the evaluation and selection of green suppliers in uncertain environment is particularly important for the long-term development of enterprises. What’s more, when the supplier’s capability gap is small, the decision-maker often hesitates among several suppliers. In this paper, the hesitant fuzzy is used to describe the hesitant psychology of decision-makers in selecting suppliers, the variance fluctuation is used to describe the characteristics of hesitant fuzzy numbers, and the probability is used to measure the uncertainty of the environment. A green supplier evaluation model under the uncertainty environment is proposed, which comprehensively evaluates the green suppliers under the uncertain environment. Furthermore, it is compared with other methods that do not consider the uncertainty and the adaptability of evaluation method and right confirmation method, so as to reflect the influence of uncertainty to green supplier evaluation and the importance of adaptability of evaluation method and right confirmation method.

Sign in / Sign up

Export Citation Format

Share Document