scholarly journals Biodegradable Plasticizing Composition for Plastics with a Limited Service Life

2020 ◽  
Author(s):  
Irina Vikhareva ◽  
Aliya Mazitova
Keyword(s):  
Service Life ◽  
Limited Service

Experiences in Examining and Dispositioning Flaws in Zr-2.5Nb Pressure Retaining CANDU Reactor Components

2002 ◽  
Author(s):  
Andrew Celovsky ◽  
John Slade
Keyword(s):  
Service Life ◽  
Reactor Core ◽  
Pressure Tube ◽  
Candu Reactors ◽  
Periodic Inspection ◽  
Pressure Tubes ◽  
Surveillance Programs ◽  
Non Destructive ◽  
Limited Service ◽  
Non Destructive Techniques

CANDU reactors use Zr-2.5 Nb alloy pressure tubes, as the primary pressure boundary within the reactor core. These components are subject to periodic inspection and material surveillance programs. Occasionally, the inspection program uncovers a flaw, whereupon the flaw is assessed as to whether it compromises the integrity of the pressure-retaining component. In 1998, such a flaw was observed in one pressure tube of a reactor. Non-destructive techniques and analysis were used to form a basis to disposition the flaw, and the component was fit for a limited service life. This component was eventually removed from service, whereupon the destructive examinations were used to validate the disposition assumptions used. Such a process of validation provides credibility to the disposition process. This paper reviews the original flaw and its subsequent destructive evaluation.

Towards Aligning and Matchmaking QoS-Based Web Service Specifications

2012 ◽  
pp. 216-257 ◽  
Author(s):  
Kyriakos Kritikos ◽  
Dimitris Plexousakis
Keyword(s):  
Life Cycle ◽  
Service Life ◽  
Web Service ◽  
Service Description ◽  
Matching Algorithm ◽  
Meta Model ◽  
Metric Matching ◽  
Service Life Cycle ◽  
Domain Independent ◽  
Limited Service

QoS plays an important role in all service life-cycle activities, and consequently, has grabbed the researchers’ attention. Concerning QoS-based service description, the various approaches proposed adopt different meta-models and propose different QoS models mostly covering domain-independent NFPs and metrics. This lack of a common QoS meta-model and model causes serious accuracy problems in QoS-based service matchmaking. While mapping between QSDs is not difficult as they rely on similar meta-models, mapping between equivalent metrics specified even with the same meta-model is challenging. For this reason, a novel QoS metric matching algorithm has been proposed for metrics specified in the OWL-Q language. In this chapter, this algorithm is exploited for aligning OWL-Q specifications. Moreover, two novel QSM algorithms are proposed that advance the state-of-the-art by solving the problems of non-coverage of QoS demand metrics by QoS offers, erroneous matchmaking metrics, limited service categorization, and non-useful result production for over-constrained QoS demands.

Cathodic modification of stainless steels with ruthenium: a review of recent advances in making the cheaper option cheaper

2018 ◽  
Vol 36 (6) ◽  
pp. 495-505
Author(s):  
Fortunate Moyo ◽  
Josias W. van der Merwe ◽  
Daniel Wamwangi ◽  
Yonela A. Mgwebi
Keyword(s):  
Corrosion Resistance ◽  
Service Life ◽  
Stainless Steels ◽  
Platinum Group Metals ◽  
Surface Alloy ◽  
Acidic Media ◽  
Cost Benefits ◽  
The Cost ◽  
Limited Service ◽  
Abrasive Suspension

AbstractCorrosion resistance of stainless steels is significantly compromised in oxygen-deficient environments, leading to limited service life as well as unsatisfactory performance of the structures made of these alloys. Cathodic modification with ruthenium has been demonstrated to remarkably improve the corrosion resistance of stainless steels in reducing acidic media, even in the presence of an abrasive suspension. Although ruthenium is several times cheaper than other platinum group metals (PGMs), alloying with ruthenium remains prohibitively more expensive than alloying with conventional, although less effective, metals. A number of strategies have been explored to reduce the amount of ruthenium required to cathodically modify stainless steels in a bid to make this cheaper option much cheaper and thus increase the cost-benefits of using these alloys. Some of the strategies include partially substituting ruthenium with cheaper metals, as well as introducing the PGM as a surface alloy.

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