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[en] Ionizing radiation is currently employed in a variety of areas, including in health care. However, due to its potentially harmful characteristics to human health, an adequate and continuous monitoring is necessary, especially regarding personal dosimetry. In this context, conjugated materials in solution have been pointed out as promising systems for the design of dosimeters. Despite the interesting properties of these systems, most of them have low sensitivity, which restricts their effective application in real situations. The present work aims the development of dosimetric systems based on solutions containing conjugated materials. Two systems were evaluated: 1) based on poly [(9,9- dioctylfluorenyl-2,7,diyl)-co-(1,4-vinylienephenylene)] polymer in chloroform solution; and 2) aqueous solutions of Indigo-carmine dye, with and without zinc oxide nanoparticles or inorganic salt (NaCl). Samples with different concentrations were considered and different X-ray doses were employed. The dosimetric responses were evaluated by analyzing the optical absorption spectrum of the systems in the ultraviolet visible range and the vibrational spectrum. The results point out the F8PV/CHCl3 system as a promising dosimeter with optimized responses in relation to other similar polymeric systems, allowing the measurement of doses lower than 5 Gy. The results were interpreted considering the interaction between free radicals generated from solvent dissociation with the polymeric chains. Non-significant responses were obtained for Indigo-carmine based systems which reinforces the essential role of halogens in the dosimetric properties of conjugated materials in solutions. (author)
[en] The paper examines the problems of linear optimization with the introduction of risks in the allocation of resources among a finite number of consumers. Risk is seen as a product of a resource and the probability for an adverse event in the allocation of that resource. Resources and risks are considered variables between which there are linear constraints. The aim is to minimize the costs of allocating resources and the insurance against the involved risks. Implementing such minimization separately for the resources and the risks solves two separate linear optimization problems, but there is a disruption in the relationship between the resources, the risks, and the probability for adverse events. The paper proposes a method in which, through an appropriate modification of variables and coefficients, a linear optimization of the costs is performed simultaneously both by the resources and by the risks, subject to all constraints and relations between resources, risks and the likelihood of adverse events. A numerical example is solved by applying the proposed method based on a linear optimization with modified variables and coefficients, consistent with linear constraints and requirements for the relations between the resources, the risks, and the probabilities of adverse events. This example shows the possibilities for practical application of the proposed method. Key words: linear optimization, resources, risks, adverse events probabilities, total costs minimization
[en] Advances in materials science and technology are helping to extend the lives of nuclear power plants, so countries can continue reaping their clean energy benefits. Most nuclear power reactors were initially built to have an operating life of between 30 and 40 years. Extending the life of a nuclear power plant involves assessing an existing plant and determining if it can safely, securely and cost-effectively continue operating past its assumed retirement date. When a plant’s life is extended, operations can often continue for an additional 20 to 40 years.
Deliberation Nr 2020-318: deliberation of the Commission for the regulation of energy of the 17 December 2020 bearing project of decision of the price of use of public networks of electric power distribution (Turpe 6 HTA-BT). Deliberation Nr 2020-314: deliberation of Commission for the regulation of energy of the 17 December 2020 bearing project of decision on the price of use of public networks of electric power transport (Turpe 6 HTB)
[en] These two publications have the same structure, with some additional details in some paragraphs in one document with respect to the other. Thus, they both report the deliberation of the Commission regarding the detail of electricity pricing, and more particularly the price of use of public electric power grids (respectively distribution and transport networks). Each document presents the competencies of the Commission and the price elaboration procedure, proposes a detailed overview of the price regulation framework (principles, time planning, incentive to cost management, to service quality and supply continuity, to R and D and innovation). It defines charges to be covered and trajectories of evolution of the price of use of public electricity networks. It discusses the details of the structure of this price (stakes, maintenance of the previous structure, evolution of the current one). As far as this structure is concerned, some additional aspects are addressed in the case of distribution networks (generalisation of the option of four time ranges, self-consumption pricing) which are not addressed in the case of transport networks
[en] To developed and introduced a measurement scale that may be useful to assess the competitive priorities practices in the manufacturing industries. The objective is to investigate the competitive priorities domains’ implementation and its defining measurement items emphasizing manufacturing industries in the Union Territory of Puducherry. The essential information has been gathered from 350 manufacturing firms by utilizing very much stretchered polls; most part of the data was gathered from best dimension working people like Operations Managers, General Managers and Directors. For analyzing the data the researchers used SPSS and LISREL 8.72 software packages. To find out the result the researchers applied Confirmatory Factor Analysis in this research work. Findings: From the six domains analyzed the result shows that Delivery plays an important role as it occupies the first rank among the domains in competitive priority. Next to Delivery, the majority of the firms fasten more importance to Quality as it ranks second. Cost is ranked as third, while Know-how is ranked as fourth, Flexibility is ranked as fifth and Customer Focus is ranked as sixth. Practical implications: Based on the existing recommendations on scale development literature, authors developed the measurement scale. This measurement scale is helpful for both academicians and practitioners. In this research work authors used the measurement scale to measure the competitive priorities domains. The research paper explains about the manufacturing industries situated in Union Territory of Puducherry. The researchers developed the measurement instrument of competitive priorities practices based on six domains namely quality, cost, delivery, flexibility, customer focus, and know-how. This research work gives innovative literature by recommendations and validating a measurement scale for the competitive priorities. The result reveals that the manufacturing enterprises in the Union Territory of Puducherry.
[en] On 8 August 2020 at 19:52 local time, unit 5 of the Tianwan nuclear power plant (NPP) in Jiangsu province, People's Republic of China, was connected to the grid. The first concrete of this ACPR1000 reactor had been poured on 27 December 2015, meaning that this milestone was achieved less than five years after construction first began (WNN, 2020). This level of construction performance contrasts with that observed in recent projects in Western OECD countries where projects have been characterised by significant delays and cost overruns. In some cases costs have more than tripled from initial estimates. This poor track record has helped create the perception of the increased overall risks associated with new NPP projects and is weighing on near term decisions over whether to pursue new developments or not. As a result, nuclear energy may be unable to deliver its expected role in reducing carbon emissions (IEA, 2020). On the other hand, successes like that in Tianwan demonstrate how the nuclear sector can deliver cost effectively and on a predictable time frame if the right conditions are in place during the planning and execution of these projects. In other words, the problem is not associated with nuclear energy as such but with specific projects. In light of these trends, in 2018 the NEA formed an ad hoc expert group to consider the issues around reducing the costs of nuclear power generation. The group's objective was to identify industrial strategies and governing frameworks to unlock significant cost reductions in the deployment of large Generation III reactors over the next decade and beyond in OECD countries. The group gathered together participants from academia, the nuclear industry and international organisations to provide a 360-degree view of the economic issues faced by nuclear new build and to collect first-hand insights of ongoing projects
[en] What is Needed for Safe, Reliable and Economic LTO?: • Ability to detect and manage plant aging: – On-going research on aging and mitigative measures – Use of harvested materials to confirm models • Modernize the existing fleet: – Improve efficiencies – Reduce operating costs • Support grid stability: – Plant flexible operations – Energy Storage
[en] Introduction: Increase the initial enrichment of nuclear fuel result in possible reduce the fuel cycle cost due to lengthening the reactor campaign from 12 to 18 or even 24 months, or due to reduction of fuel batch every year 1/3, 1/4 or 1/5 part of the core Currently, the initial enrichment of fuel is steadily approaching the mark of 5% and average burnup has already exceeded the level of 50 MWd/tU Now an objective of the transition of initial enrichment to the range of 5 -10% and the burn up to 100 MWd/tU becomes on the agenda.
[en] Today, with the completion of First-of-a-Kind Gen-III nuclear reactors, the nuclear sector is at a critical juncture. These reactors have led in several parts of the world to delays and construction costs overruns that have challenged the competitiveness of nuclear power and are driving the risk perception of future projects. Against this background, a review of historical and recent lessons learnt from nuclear and non-nuclear project offers ample evidence that nuclear new build can be delivered cost and time-effectively. This study assesses the policy and governance frameworks needed to drive positive learning and continuous industrial performance for nuclear new build. The study also explores the risk allocation and mitigation priorities needed to define adequate financing schemes for these projects. In the longer-term, it identifies cost reduction opportunities associated with the harmonisation of code and standards and licensing regimes and new innovative designs (i.e. small modular reactors and advanced reactors)