Multilevel Risk-Based Inspection Scheme for FPSOs

2007 ◽  
Vol 44 (02) ◽  
pp. 118-124
Author(s):  
A.K. Lee ◽  
C. Serratella ◽  
G. Wang ◽  
R. Basu ◽  
R. Spong

As the floating, production, storage, and off-loading (FPSO) fleet matures, the challenge of how to more rationally and efficiently manage the life-cycle integrity of an FPSO attracts more attention. Risk-and reliability-based approaches are regarded as very powerful tools to help optimize an integrity program and offer flexibility in helping better manage the integrity management regime. This paper presents a multilevel risk-based inspection (RBI) methodology ranging from simplified deterministic approaches using standard design analysis up to sophisticated probabilistic approaches. Each approach has various levels of usefulness ranging from the definition of critical areas for a single inspection campaign up to the generation of an optimized inspection schedule and work scope covering the entire life cycle of a particular unit. These RBI methodologies have been successfully applied in inspection planning for several FPSO installations. A wide range of engineering analyses were involved, depending on the needs of individual projects and client requests, inspection objectives, condition of the asset, availability of design analysis information, and so forth.

Author(s):  
Denis Tikhomirov

The purpose of the article is to typologize terminological definitions of security, to find out the general, to identify the originality of their interpretations depending on the subject of legal regulation. The methodological basis of the study is the methods that made it possible to obtain valid conclusions, in particular, the method of comparison, through which it became possible to correlate different interpretations of the term "security"; method of hermeneutics, which allowed to elaborate texts of normative legal acts of Ukraine, method of typologization, which made it possible to create typologization groups of variants of understanding of the term "security". Scientific novelty. The article analyzes the understanding of the term "security" in various regulatory acts in force in Ukraine. Typological groups were understood to understand the term "security". Conclusions. The analysis of the legal material makes it possible to confirm that the issues of security are within the scope of both legislative regulation and various specialized by-laws. However, today there is no single conception on how to interpret security terminology. This is due both to the wide range of social relations that are the subject of legal regulation and to the relativity of the notion of security itself and the lack of coherence of views on its definition in legal acts and in the scientific literature. The multiplicity of definitions is explained by combinations of material and procedural understanding, static - dynamic, and conditioned by the peculiarities of a particular branch of legal regulation, limited ability to use methods of one or another branch, the inter-branch nature of some variations of security, etc. Separation, common and different in the definition of "security" can be used to further standardize, in fact, the regulatory legal understanding of security to more effectively implement the legal regulation of the security direction.


Author(s):  
Tim Rutherford-Johnson

By the start of the 21st century many of the foundations of postwar culture had disappeared: Europe had been rebuilt and, as the EU, had become one of the world’s largest economies; the United States’ claim to global dominance was threatened; and the postwar social democratic consensus was being replaced by market-led neoliberalism. Most importantly of all, the Cold War was over, and the World Wide Web had been born. Music After The Fall considers contemporary musical composition against this changed backdrop, placing it in the context of globalization, digitization, and new media. Drawing on theories from the other arts, in particular art and architecture, it expands the definition of Western art music to include forms of composition, experimental music, sound art, and crossover work from across the spectrum, inside and beyond the concert hall. Each chapter considers a wide range of composers, performers, works, and institutions are considered critically to build up a broad and rich picture of the new music ecosystem, from North American string quartets to Lebanese improvisers, from South American electroacoustic studios to pianos in the Australian outback. A new approach to the study of contemporary music is developed that relies less on taxonomies of style and technique, and more on the comparison of different responses to common themes, among them permission, fluidity, excess, and loss.


Author(s):  
J. Schiffmann

Small scale turbomachines in domestic heat pumps reach high efficiency and provide oil-free solutions which improve heat-exchanger performance and offer major advantages in the design of advanced thermodynamic cycles. An appropriate turbocompressor for domestic air based heat pumps requires the ability to operate on a wide range of inlet pressure, pressure ratios and mass flows, confronting the designer with the necessity to compromise between range and efficiency. Further the design of small-scale direct driven turbomachines is a complex and interdisciplinary task. Textbook design procedures propose to split such systems into subcomponents and to design and optimize each element individually. This common procedure, however, tends to neglect the interactions between the different components leading to suboptimal solutions. The authors propose an approach based on the integrated philosophy for designing and optimizing gas bearing supported, direct driven turbocompressors for applications with challenging requirements with regards to operation range and efficiency. Using previously validated reduced order models for the different components an integrated model of the compressor is implemented and the optimum system found via multi-objective optimization. It is shown that compared to standard design procedure the integrated approach yields an increase of the seasonal compressor efficiency of more than 12 points. Further a design optimization based sensitivity analysis allows to investigate the influence of design constraints determined prior to optimization such as impeller surface roughness, rotor material and impeller force. A relaxation of these constrains yields additional room for improvement. Reduced impeller force improves efficiency due to a smaller thrust bearing mainly, whereas a lighter rotor material improves rotordynamic performance. A hydraulically smoother impeller surface improves the overall efficiency considerably by reducing aerodynamic losses. A combination of the relaxation of the 3 design constraints yields an additional improvement of 6 points compared to the original optimization process. The integrated design and optimization procedure implemented in the case of a complex design problem thus clearly shows its advantages compared to traditional design methods by allowing a truly exhaustive search for optimum solutions throughout the complete design space. It can be used for both design optimization and for design analysis.


Author(s):  
Branka Vulesevic ◽  
Naozumi Kubota ◽  
Ian G Burwash ◽  
Claire Cimadevilla ◽  
Sarah Tubiana ◽  
...  

Abstract Aims Severe aortic valve stenosis (AS) is defined by an aortic valve area (AVA) <1 cm2 or an AVA indexed to body surface area (BSA) <0.6 cm/m2, despite little evidence supporting the latter approach and important intrinsic limitations of BSA indexation. We hypothesized that AVA indexed to height (H) might be more applicable to a wide range of populations and body morphologies and might provide a better predictive accuracy. Methods and results In 1298 patients with degenerative AS and preserved ejection fraction from three different countries and continents (derivation cohort), we aimed to establish an AVA/H threshold that would be equivalent to 1.0 cm2 for defining severe AS. In a distinct prospective validation cohort of 395 patients, we compared the predictive accuracy of AVA/BSA and AVA/H. Correlations between AVA and AVA/BSA or AVA/H were excellent (all R2 > 0.79) but greater with AVA/H. Regressions lines were markedly different in obese and non-obese patients with AVA/BSA (P < 0.0001) but almost identical with AVA/H (P = 0.16). AVA/BSA values that corresponded to an AVA of 1.0 cm2 were markedly different in obese and non-obese patients (0.48 and 0.59 cm2/m2) but not with AVA/H (0.61 cm2/m for both). Agreement for the diagnosis of severe AS (AVA < 1 cm2) was significantly higher with AVA/H than with AVA/BSA (P < 0.05). Similar results were observed across the three countries. An AVA/H cut-off value of 0.6 cm2/m [HR = 8.2(5.6–12.1)] provided the best predictive value for the occurrence of AS-related events [absolute AVA of 1 cm2: HR = 7.3(5.0–10.7); AVA/BSA of 0.6 cm2/m2 HR = 6.7(4.4–10.0)]. Conclusion In a large multinational/multiracial cohort, AVA/H was better correlated with AVA than AVA/BSA and a cut-off value of 0.6 cm2/m provided a better diagnostic and prognostic value than 0.6 cm2/m2. Our results suggest that severe AS should be defined as an AVA < 1 cm2 or an AVA/H < 0.6 cm2/m rather than a BSA-indexed value of 0.6 cm2/m2.


2021 ◽  
Vol 31 ◽  
Author(s):  
ANDREA VEZZOSI ◽  
ANDERS MÖRTBERG ◽  
ANDREAS ABEL

Abstract Proof assistants based on dependent type theory provide expressive languages for both programming and proving within the same system. However, all of the major implementations lack powerful extensionality principles for reasoning about equality, such as function and propositional extensionality. These principles are typically added axiomatically which disrupts the constructive properties of these systems. Cubical type theory provides a solution by giving computational meaning to Homotopy Type Theory and Univalent Foundations, in particular to the univalence axiom and higher inductive types (HITs). This paper describes an extension of the dependently typed functional programming language Agda with cubical primitives, making it into a full-blown proof assistant with native support for univalence and a general schema of HITs. These new primitives allow the direct definition of function and propositional extensionality as well as quotient types, all with computational content. Additionally, thanks also to copatterns, bisimilarity is equivalent to equality for coinductive types. The adoption of cubical type theory extends Agda with support for a wide range of extensionality principles, without sacrificing type checking and constructivity.


Author(s):  
Ying Pin Chua ◽  
Ying Xie ◽  
Poay Sian Sabrina Lee ◽  
Eng Sing Lee

Background: Multimorbidity presents a key challenge to healthcare systems globally. However, heterogeneity in the definition of multimorbidity and design of epidemiological studies results in difficulty in comparing multimorbidity studies. This scoping review aimed to describe multimorbidity prevalence in studies using large datasets and report the differences in multimorbidity definition and study design. Methods: We conducted a systematic search of MEDLINE, EMBASE, and CINAHL databases to identify large epidemiological studies on multimorbidity. We used the Preferred Reporting Items for Systematic Reviews and Meta-analysis Extension for Scoping Reviews (PRISMA-ScR) protocol for reporting the results. Results: Twenty articles were identified. We found two key definitions of multimorbidity: at least two (MM2+) or at least three (MM3+) chronic conditions. The prevalence of multimorbidity MM2+ ranged from 15.3% to 93.1%, and 11.8% to 89.7% in MM3+. The number of chronic conditions used by the articles ranged from 15 to 147, which were organized into 21 body system categories. There were seventeen cross-sectional studies and three retrospective cohort studies, and four diagnosis coding systems were used. Conclusions: We found a wide range in reported prevalence, definition, and conduct of multimorbidity studies. Obtaining consensus in these areas will facilitate better understanding of the magnitude and epidemiology of multimorbidity.


2016 ◽  
Vol 26 (5) ◽  
pp. 1134-1157 ◽  
Author(s):  
Donghee Shin ◽  
Myunggoon Choi ◽  
Jang Hyun Kim ◽  
Jae-gil Lee

Purpose The purpose of this paper is to examine the effects of interaction techniques (e.g. swiping and tapping) and the range of thumb movement on interactivity, engagement, attitude, and behavioral intention in single-handed interaction with smartphones. Design/methodology/approach A 2×2 between-participant experiment (technological features: swiping and tapping×range of thumb movement: wide and narrow) was conducted to study the effects of interaction techniques and thumb movement ranges. Findings The results showed that the range of thumb movement had significant effects on perceived interactivity, engagement, attitude, and behavioral intention, whereas no effects were observed for interaction techniques. A narrow range of thumb movement had more influence on the interactivity outcomes in comparison to a wide range of thumb movement. Practical implications While the subject of actual and perceived interactivity has been discussed, the issue has not been applied to smartphone. Based on the research results, the mobile industry may come up with a design strategy that balances feature- and perception-based interactivity. Originality/value This study adopted the perspective of the hybrid definition of interactivity, which includes both actual and perceived interactivity. Interactivity effect outcomes mediated by perceived interactivity.


Author(s):  
Aditya Das ◽  
Rakesh Murthy

One of the major challenges in commercializable micro-nano systems development is the high cost and turnaround that are incurred through multiple product-optimization iterations and expensive fabrication processes for specific systems. Development of complex and heterogeneous micro-nano systems, that are only possible through assembly and not by conventional surface machining approaches, are further impeded by lack of standard design rules and off-the-shelf robotic manipulation systems. Dedicated hardware and system specific component designs, although possible, are not commercially viable for addressing the wide range of opportunities that exists in the prevailing micro-nano domain. In this paper, we present an alternative and holistic top-down approach for micro-nano manufacturing using modular part designs and flexible assembly systems. We incorporate, seamlessly, multiple novel algorithms related to microrobotics and scaling of physics, obtained both analytically as well as experimentally; in order to predict, track and control the uncertainty propagation in a typical manufacturing process, in micro-nano scale, throughout production steps including design, machining, setup, assembly, testing etc. We demonstrate, through multiple examples, the implementation of the proposed framework in micro-nano scale manufacturing.


2016 ◽  
Vol 3 (11) ◽  
pp. 160270 ◽  
Author(s):  
Taro Takaguchi ◽  
Yuichi Yoshida

When we represent real-world systems as networks, the directions of links often convey valuable information. Finding module structures that respect link directions is one of the most important tasks for analysing directed networks. Although many notions of a directed module have been proposed, no consensus has been reached. This lack of consensus results partly because there might exist distinct types of modules in a single directed network, whereas most previous studies focused on an independent criterion for modules. To address this issue, we propose a generic notion of the so-called truss structures in directed networks. Our definition of truss is able to extract two distinct types of trusses, named the cycle truss and the flow truss, from a unified framework. By applying the method for finding trusses to empirical networks obtained from a wide range of research fields, we find that most real networks contain both cycle and flow trusses. In addition, the abundance of (and the overlap between) the two types of trusses may be useful to characterize module structures in a wide variety of empirical networks. Our findings shed light on the importance of simultaneously considering different types of modules in directed networks.


2021 ◽  
Vol 13 (9) ◽  
pp. 4886
Author(s):  
Katia Perini ◽  
Fabio Magrassi ◽  
Andrea Giachetta ◽  
Luca Moreschi ◽  
Michela Gallo ◽  
...  

Urban greening provides a wide range of ecosystem services to address the main challenges of urban areas, e.g., carbon sequestration, evapotranspiration and shade, thermal insulation, and pollution control. This study evaluates the environmental sustainability of a vertical greening system (VGS) built in 2014 in Italy, for which extensive monitoring activities were implemented. The life-cycle assessment methodology was applied to quantify the water–energy–climate nexus of the VGS for 1 m2 of the building’s wall surface. Six different scenarios were modelled according to three different end-of-life scenarios and two different useful lifetime scenarios (10 and 25 years). The environmental impact of global-warming potential and generated energy consumption during the use phase in the VGS scenarios were reduced by 56% in relation to the baseline scenario (wall without VGS), and showed improved environmental performance throughout the complete life cycle. However, the water-scarcity index (WSI) of the VGS scenarios increased by 42%. This study confirms that the installation of VGSs offers a relevant environmental benefit in terms of greenhouse-gas emissions and energy consumption; however, increased water consumption in the use phase may limit the large-scale application of VGSs.


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