Next Generation CANDU Performance Assurance

2002 ◽  
Author(s):  
David J. Wren ◽  
P. J. Allsop ◽  
J. M. Hopwood
Keyword(s):  
Product Development ◽  
Large Scale ◽  
Low Cost ◽  
Development Program ◽  
Next Generation ◽  
Customer Expectations ◽  
Generation Plant ◽  
Reliable Performance ◽  
And Performance ◽  
Under Construction

AECL is developing a next generation CANDU design to meet market requirements for low cost, reliable energy supplies. The primary product development objective is to achieve a capital cost substantially lower than the current nuclear plant costs, such that the next generation plant will be competitive with alternative options for large-scale base-load electricity supply. However, other customer requirements, including safety, low-operating costs and reliable performance, are being addressed as equally important design requirements. The main focus of this paper is to address the development directions that will provide performance assurance. The next generation CANDU is an evolutionary extension of the proven CANDU 6 design. There are eight CANDU 6 units in operation in four countries around the world and further three units are under construction. These units provide a sound basis for projecting highly reliable performance for the next generation CANDU. In addition, the next generation CANDU program includes development and qualification activities that will address the new features and design extensions in the advanced plant. To limit product development risk and to enhance performance assurance, the next generation CANDU design features and performance parameters have been carefully reviewed during the concept development phase and have been deliberately selected so as to be well founded on the existing CANDU knowledge base. Planned research and development activities are required only to provide confirmation of the projected performance within a modest extension of the established database. Necessary qualification tests will be carried out within the timeframe of the development program, to establish a proven design prior to the start of a construction project. This development support work coupled with ongoing AECL programs to support and enhance the performance and reliability of the existing CANDU plants will provide sound assurance that the next generation CANDU plants will meet customer expectations.

Community Monitoring Improves Public Service Provision at Scale: Experimental Evidence from a Child Development Program in Nicaragua

2020 ◽  
Author(s):  
Florencia López Boo ◽  
Jane Leer ◽  
Akito Kamei
Keyword(s):  
Child Development ◽  
Experimental Evidence ◽  
Large Scale ◽  
Service Providers ◽  
Low Cost ◽  
Development Program ◽  
Small Scale ◽  
Community Monitoring ◽  
Quality Assurance Mechanism ◽  
Intent To Treat

Expanding small-scale interventions without lowering quality and attenuating impact is a critical policy challenge. Community monitoring overs a low-cost quality assurance mechanism by making service providers account-able to local citizens, rather than distant administrators. This paper provides experimental evidence from a home visit parenting program implemented at scale by the Nicaraguan government, with two types of monitoring: (a) institutional monitoring; and (b) community monitoring. We find d a positive intent-to-treat effect on child development, but only among groups randomly assigned to community monitoring. Our findings show promise for the use of community monitoring to ensure quality in large-scale government-run social programs.

scholarly journals Lethe: Conceal Content Deletion from Persistent Observers

2019 ◽  
Vol 2019 (1) ◽  
pp. 206-226
Author(s):  
Mohsen Minaei ◽  
Mainack Mondal ◽  
Patrick Loiseau ◽  
Krishna Gummadi ◽  
Aniket Kate
Keyword(s):  
Large Scale ◽  
Real Data ◽  
Significant Fraction ◽  
Next Generation ◽  
Time Duration ◽  
Trade Off ◽  
Right To Be Forgotten ◽  
User Data ◽  
And Performance ◽  
Content Availability

Abstract Most social platforms offer mechanisms allowing users to delete their posts, and a significant fraction of users exercise this right to be forgotten. However, ironically, users’ attempt to reduce attention to sensitive posts via deletion, in practice, attracts unwanted attention from stalkers specifically to those (deleted) posts. Thus, deletions may leave users more vulnerable to attacks on their privacy in general. Users hoping to make their posts forgotten face a “damned if I do, damned if I don’t” dilemma. Many are shifting towards ephemeral social platform like Snapchat, which will deprive us of important user-data archival. In the form of intermittent withdrawals, we present, Lethe, a novel solution to this problem of (really) forgetting the forgotten. If the next-generation social platforms are willing to give up the uninterrupted availability of non-deleted posts by a very small fraction, Lethe provides privacy to the deleted posts over long durations. In presence of Lethe, an adversarial observer becomes unsure if some posts are permanently deleted or just temporarily withdrawn by Lethe; at the same time, the adversarial observer is overwhelmed by a large number of falsely flagged undeleted posts. To demonstrate the feasibility and performance of Lethe, we analyze large-scale real data about users’ deletion over Twitter and thoroughly investigate how to choose time duration distributions for alternating between temporary withdrawals and resurrections of non-deleted posts. We find a favorable trade-off between privacy, availability and adversarial overhead in different settings for users exercising their right to delete. We show that, even against an ultimate adversary with an uninterrupted access to the entire platform, Lethe offers deletion privacy for up to 3 months from the time of deletion, while maintaining content availability as high as 95% and keeping the adversarial precision to 20%.

scholarly journals Advances in low-cost and nontoxic materials based solar cell devices

2021 ◽  
Vol 2070 (1) ◽  
pp. 012043
Author(s):  
S S Hegde ◽  
K Ramesh
Keyword(s):  
Thin Film ◽  
Solar Cells ◽  
Solar Cell ◽  
Absorption Coefficient ◽  
Large Scale ◽  
Resource Constraints ◽  
Low Cost ◽  
Future Research ◽  
Tin Sulfide ◽  
Next Generation

Abstract Photovoltaics (PV) have become increasingly popular and reached as the third-largest renewable energy source. Thin-film solar cells made from earth-abundant, inexpensive and environmentally friendly materials are needed to replace the current PV technologies whose large-scale applications are limited by material and/or resource constraints. Near optimum direct optical bandgap of 1.3 eV, high absorption coefficient (>104 cm−1), less toxic, and abundant raw resources along with considerable scalability have made tin sulfide (SnS) as a strategic choice for next-generation PVs. In this review, limitations of leading commercial PV technologies and the status of a few alternate low-cost PV materials are outlined. Recent literature on crucial physical properties of SnS thin-films and the present status of SnS thin-film-based solar cells are discussed. Deficiency and adequacy of some of the key properties of SnS including carrier mobility (μ), minority carrier lifetime (τ), and absorption coefficient (α) are discussed in comparison of existing commercial solar cell materials. Future research trends on SnS based solar cells to enhance their conversion efficiencies towards the theoretical maximum of 24% from present ~5% and its prospectus as next-generation solar cell is also discussed.

scholarly journals Benefit and performance impact analysis of using hydrogen fuel cell powered e-taxi system on A320 class airliner

2019 ◽  
Vol 123 (1261) ◽  
pp. 378-397
Author(s):  
J. A. Stockford ◽  
C. Lawson ◽  
Z. Liu
Keyword(s):  
Fuel Cell ◽  
Large Scale ◽  
Impact Analysis ◽  
Low Cost ◽  
Operating Cost ◽  
Maintenance Cost ◽  
Hydrogen Fuel Cell ◽  
Hydrogen Fuel ◽  
And Performance ◽  
The Impact

ABSTRACTThis paper presents the work carried out to evaluate the benefits and performance impacts of introducing a hydrogen fuel cell powered electric taxiing system to a conventional short-haul aircraft. Tasks carried out in this research and reported in this paper include the initial system design, hydrogen tank initial sizing, calculation of the impact on fuel burn and emissions and the evaluation of the effects on Direct Operating Cost (DOC). The Airbus A320 has been selected as the datum aircraft for sizing the system, and the benefits analysis is particularly focused on the fleet composition and financial data of a Europe-based, low-cost, large-scale A320 family operator in 2016. The maximum power capacity of 400 kW has been sized based on the rolling friction coefficient of 0.02. Based on the operator’s 2016 financial, up to 1% fuel reduction can be achieved using the proposed system and the reduction in total maintenance cost is expected to be up to 7.3%. Additionally, up to 5.97% net profit improvement is estimated in comparison with the annual after-tax profit of the datum operator in 2016.

scholarly journals Environmental Impacts of Distributed Manufacturing from 3-D Printing of Polymer Components and Products

2013 ◽  
Vol 1492 ◽  
pp. 85-90 ◽  
Author(s):  
Megan Kreiger ◽  
Joshua M. Pearce
Keyword(s):  
Environmental Impact ◽  
Open Source ◽  
Large Scale ◽  
Low Cost ◽  
Acrylonitrile Butadiene Styrene ◽  
Mass Scale ◽  
Embodied Energy ◽  
Scale Production ◽  
Distributed Manufacturing ◽  
And Performance

ABSTRACTAlthough additive layer manufacturing is well established for rapid prototyping the low throughput and historic costs have prevented mass-scale adoption. The recent development of the RepRap, an open source self-replicating rapid prototyper, has made low-cost 3-D printers readily available to the public at reasonable prices (<$1,000). The RepRap (Prusa Mendell variant) currently prints 3-D objects in a 200x200x140 square millimeters build envelope from acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA). ABS and PLA are both thermoplastics that can be injection-molded, each with their own benefits, as ABS is rigid and durable, while PLA is plant-based and can be recycled and composted. The melting temperature of ABS and PLA enable use in low-cost 3-D printers, as these temperature are low enough to use in melt extrusion in the home, while high enough for prints to retain their shape at average use temperatures. Using 3-D printers to manufacture provides the ability to both change the fill composition by printing voids and fabricate shapes that are impossible to make using tradition methods like injection molding. This allows more complicated shapes to be created while using less material, which could reduce environmental impact.As the open source 3-D printers continue to evolve and improve in both cost and performance, the potential for economically-viable distributed manufacturing of products increases. Thus, products and components could be customized and printed on-site by individual consumers as needed, reversing the historical trend towards centrally mass-manufactured and shipped products. Distributed manufacturing reduces embodied transportation energy from the distribution of conventional centralized manufacturing, but questions remain concerning the potential for increases in the overall embodied energy of the manufacturing due to reduction in scale. In order to quantify the environmental impact of distributed manufacturing using 3-D printers, a life cycle analysis was performed on a plastic juicer. The energy consumed and emissions produced from conventional large-scale production overseas are compared to experimental measurements on a RepRap producing identical products with ABS and PLA. The results of this LCA are discussed in relation to the environmental impact of distributed manufacturing with 3-D printers and polymer selection for 3-D printing to reduce this impact. The results of this study show that distributed manufacturing uses less energy than conventional manufacturing due to the RepRap's unique ability to reduce fill composition. Distributed manufacturing also has less emissions than conventional manufacturing when using PLA and when using ABS with solar photovoltaic power. The results of this study indicate that open-source additive layer distributed manufacturing is both technically viable and beneficial from an ecological perspective.

Organizational Innovation Promoters and Performance Effects in Small, Knowledge-Intensive Firms

2010 ◽  
Vol 11 (1) ◽  
pp. 19-27 ◽  
Author(s):  
Jan Inge Jenssen ◽  
Kari Aasheim
Keyword(s):  
Product Development ◽  
Organizational Innovation ◽  
Low Cost ◽  
Organizational Factors ◽  
Performance Effects ◽  
Development Context ◽  
External Relationships ◽  
Low Cost Strategy ◽  
Knowledge Intensive ◽  
And Performance

This paper investigates the impacts of organizational factors on innovation and performance in small, knowledge-intensive firms. The study focused on Norwegian firms with 5 to 30 employees. The findings indicate that differentiating between product, process and market innovation provides a better understanding of the factors that drive innovation. This strategy seems to influence innovation. For instance, low-cost strategy positively impacts on both process innovation and market innovation. Also, external relationships significantly influence innovation: for instance, market participation in a product development context has a significant influence on product development.

scholarly journals Dual mechanism β-amino acid polymers promoting cell adhesion

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Qi Chen ◽  
Donghui Zhang ◽  
Wenjing Zhang ◽  
Haodong Zhang ◽  
Jingcheng Zou ◽  
...  
Keyword(s):  
Cell Adhesion ◽  
Amino Acid ◽  
Large Scale ◽  
Low Cost ◽  
Next Generation ◽  
Cell Adhesive ◽  
Scale Preparation ◽  
Amino Acid Polymers ◽  
Adhesive Proteins ◽  
Adhesive Materials

AbstractCell adhesion has tremendous impact on the function of culture platforms and implants. Cell-adhesive proteins and peptides have been extensively used for decades to promote cell adhesion, however, their application suffers from their easy enzymatic degradation, difficulty in large-scale preparation and expensiveness. To develop the next-generation cell-adhesive materials, we mimic the cell adhesion functions and mechanisms of RGD and KRSR peptides and design cell-adhesive cationic-hydrophobic amphiphilic β-amino acid polymers that are stable upon proteolysis and easily prepared in large scale at low cost. The optimal polymer strongly promotes cell adhesion, using preosteoblast cell as a model, by following dual mechanisms that are independent of sequence and chirality of the statistic copolymer. Our strategy opens avenues in designing the next-generation cell-adhesive materials and may guide future studies and applications.

scholarly journals Design of a Three Surfaces R/C Aircraft Model

10.14311/314 ◽  
2002 ◽  
Vol 42 (1) ◽  
Author(s):  
D. P. Coiro ◽  
F. Nicolosi
Keyword(s):  
Cost Model ◽  
Low Cost ◽  
Aerodynamic Characteristics ◽  
Flight Behavior ◽  
Material Structure ◽  
Aircraft Model ◽  
Lifting Surfaces ◽  
And Performance ◽  
Under Construction ◽  
High Angles Of Attack

Design of a three lifting surfaces radio-controlled model has been carried out at Dipartimento di Progettazione Aeronautica (DPA) by the authors in the last year. The model is intended to be a UAV prototype and is now under construction. The main goal of this small aircraft's design is to check the influence of the canard surface on the aircraft's aerodynamic characteristics and flight behavior, especially at high angles of attack. The aircraft model is also intended to be a flying platform to test sensors, measurement and acquisition systems for research purposes and a valid and low-cost teaching instrument for flight dynamics and flight maneuvering. The aircraft has been designed to fly with and without canard, and all problems relative to aircraft balance and stability have been carefully analyzed and solved. The innovative configuration and the mixed wooden-composite material structure has been obtained with very simple shapes and all the design is focused on realizing a low-cost model. A complete aerodynamic analysis of the configuration up to high angles of attack and a preliminary aircraft stability and performance prediction will be presented.

scholarly journals Design and performance of a low-cost, automated, large-scale photobioreactor for microalgae production

2020 ◽  
Vol 90 ◽  
pp. 102103
Author(s):  
Patrick Erbland ◽  
Sarah Caron ◽  
Michael Peterson ◽  
Andrei Alyokhin
Keyword(s):  
Large Scale ◽  
Low Cost ◽  
And Performance

scholarly journals Anti-Perovskites for Solid-State Batteries: Recent Developments, Current Challenges and Future Prospects

2021 ◽  
Author(s):  
James Dawson ◽  
Theodosios Famprikis ◽  
Karen E Johnston
Keyword(s):  
Solid State ◽  
High Performance ◽  
Large Scale ◽  
Low Cost ◽  
Next Generation ◽  
Future Prospects ◽  
Recent Developments ◽  
Solid State Batteries ◽  
The Creation

Current commercial batteries cannot meet the requirements of next-generation technologies, meaning that the creation of new high-performance batteries at low cost is essential for the electrification of transport and large-scale...

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