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1 – 10 of over 18000Haiying Liu, Weisong Ye and Huinan Wang
The purpose of this paper is to develop an integrity monitoring method using ERAIM (Extended Receiver Autonomous Integrity Monitoring) for the integrated GNSS/Inertial (Global…
Abstract
Purpose
The purpose of this paper is to develop an integrity monitoring method using ERAIM (Extended Receiver Autonomous Integrity Monitoring) for the integrated GNSS/Inertial (Global Navigation Satellite System and inertial navigation system) of general aviation aircraft.
Design/methodology/approach
First the tightly integrated GNSS with Strapdown Inertial Navigation System (GNSS/SINS) and the Kalman filter is designed. Then the processing of ERAIM is presented, in which the least‐squares theory is used to calculate the best estimators by integrating the predicted states with measurement states of Kalman filter. Based on the new measurement model, the integrity monitoring for GNSS/inertial system is carried out, including the fault detection, identification, reliability and separability. Lastly, the simulation and analysis for ERAIM vs RAIM are performed to validate the proposed method.
Findings
Simulation results show that the ERAIM method is able to detect and identify effectively any type of failure including step failure and ramp failure. Compared to the RAIM method for only GNSS, the ERAIM increases the redundant information and reduces the correlation of test statistics, as well as enhancing the reliability and thus can significantly improve the performance of integrity monitoring.
Practical implications
In safety critical sectors such as aviation, stringent integrity performance requirements must be met. The ERAIM method cannot only be used in integrity monitoring for the integrated GNSS/Inertial system, but also can be applied to only GNSS or other integrated navigation systems for general aviation aircraft.
Originality/value
The paper presents a new integrity monitoring method of ERAIM, which is able to improve the fault detection and identification capabilities significantly by extending GNSS‐used RAIM method into the GNSS/Inertial integrated system.
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Michael Macaulay, Gary Hickey and Norjahan Begum
This chapter looks at the development of the concepts of ethical governance within the English local government structure. It examines this development by reference both to the…
Abstract
Purpose
This chapter looks at the development of the concepts of ethical governance within the English local government structure. It examines this development by reference both to the current crisis in funding and service provision, and also to the development of standards for good governance and integrity.
Design
The chapter draws upon a national survey that was conducted by the authors in 2012.
Findings
The chapter suggests that while there may have been a wish to create more opportunities for devolved decision-making in English local government through changes in legislation, those policy-makers surveyed thought that the structures and processes of decision-making might be weakened.
Implications
The chapter indicates not just the need for further studies but also a more holistic exploration of the relationships between the ideas of ‘good governance’ and whose different interests are met through such changes.
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This paper describes a recent collaborative project involving the development of a multiplexed fibre Bragg grating (FBG) sensor system for structural integrity monitoring.
Abstract
Purpose
This paper describes a recent collaborative project involving the development of a multiplexed fibre Bragg grating (FBG) sensor system for structural integrity monitoring.
Design/methodology/approach
The system is described and field trials on both conventional and novel composite bridges are discussed. A FBG sensor‐based structural monitoring system was developed, based on a fluorescent fibre as the optical source. It used a tuneable, fibre‐coupled, Fabry‐Perot filter, actuated by piezoelectric transducers and operated over the bandwidth of the source at up to 250 scans/second. Light from the source was filtered and reflected back from the Bragg gratings, through optical couplers, to eight photodiode detectors. These detected the resulting time‐domain spectra of the sensors in each of the serially connected sensor arrays. The system was tested at City University and then subjected to trials on the Mjosund road bridge in Norway and on West Mill bridge in Oxfordshire, UK, which is the first bridge to be fabricated from a new type of composite material.
Findings
During the Norwegian trials the system was arranged with four or five FBG sensors per channel giving a total of 32 measurement points with eight parallel channels. Twelve conventional foil strain gauges and a number of thermocouples were also installed. Different static and dynamic loads were applied over a period of 18 months and the results showed that the thermally compensated strain data obtained optically matched those from the resistive gauges to within <5 με. During the construction stage of the Oxfordshire bridge, sections of the decking and longitudinal composite support beams were instrumented with 40 FBG sensors with temperature compensation, placed at pre‐selected sites of maximum strain. These exhibited a resolution of ±5 με and an operating range of over ±2,000 με.
Originality/value
This research has shown that multiplexed, multi‐point FBG sensor systems can accurately and reliably monitor both static and dynamic strains in large structures over a range of temperatures and for extended periods of time.
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Kathleen Lynne Lane, Eric Alan Common, Mark Matthew Buckman and Grant Allen
Tiered systems may hold particular benefit for students with intensive intervention needs, as this continuum of supports is ideally comprised of evidence-based practices. In this…
Abstract
Tiered systems may hold particular benefit for students with intensive intervention needs, as this continuum of supports is ideally comprised of evidence-based practices. In this chapter, we explore three intensive interventions: functional assessment-based interventions (FABI), First Step to Success, and Read 180 as they feature a range of practices and programs to meet students' academic, behavioral, and social needs. We define and describe each intervention, including information on essential features necessary for drawing valid inferences: treatment integrity, social validity, as well as student performance. We also provide examples of supporting evidence, featuring treatment-outcome studies documenting intervention effectiveness. We close with clarifications and considerations for meeting the multiple needs of students requiring intensive intervention efforts.
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Prasanta Kumar Dey, Stephen O. Ogunlana and Sittichai Naksuksakul
Offshore oil and gas pipelines are vulnerable to environment as any leak and burst in pipelines cause oil/gas spill resulting in huge negative impacts on marine lives. Breakdown…
Abstract
Offshore oil and gas pipelines are vulnerable to environment as any leak and burst in pipelines cause oil/gas spill resulting in huge negative impacts on marine lives. Breakdown maintenance of these pipelines is also cost‐intensive and time‐consuming resulting in huge tangible and intangible loss to the pipeline operators. Pipelines health monitoring and integrity analysis have been researched a lot for successful pipeline operations and risk‐based maintenance model is one of the outcomes of those researches. This study develops a risk‐based maintenance model using a combined multiple‐criteria decision‐making and weight method for offshore oil and gas pipelines in Thailand with the active participation of experienced executives. The model's effectiveness has been demonstrated through real life application on oil and gas pipelines in the Gulf of Thailand. Practical implications. Risk‐based inspection and maintenance methodology is particularly important for oil pipelines system, as any failure in the system will not only affect productivity negatively but also has tremendous negative environmental impact. The proposed model helps the pipelines operators to analyze the health of pipelines dynamically, to select specific inspection and maintenance method for specific section in line with its probability and severity of failure.
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The existing method of pipeline health monitoring, which requires an entire pipeline to be inspected periodically, is both time‐wasting and expensive. A risk‐based model that…
Abstract
The existing method of pipeline health monitoring, which requires an entire pipeline to be inspected periodically, is both time‐wasting and expensive. A risk‐based model that reduces the amount of time spent on inspection has been presented. This model not only reduces the cost of maintaining petroleum pipelines, but also suggests efficient design and operation philosophy, construction methodology and logical insurance plans. The risk‐based model uses Analytic Hierarchy Process (AHP), a multiple attribute decision‐making technique, to identify the factors that influence failure on specific segments and analyzes their effects by determining probability of risk factors. The severity of failure is determined through consequence analysis. From this, the effect of a failure caused by each risk factor can be established in terms of cost, and the cumulative effect of failure is determined through probability analysis. The technique does not totally eliminate subjectivity, but it is an improvement over the existing inspection method.
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Just as managers and accountants were becoming used to the idea that tanks should be regularly emptied for inspection, Forbes Tankguard arrives with its proposal that emptying is…
Lynn McDonald, Gail Coover, Jen Sandler, Toua Thao and Huda Shalhoub
Without some flexibility, replications of manualised evidence‐based programmes (EBP) may not achieve predictable outcomes due to differences in cultural priorities. In this case…
Abstract
Purpose
Without some flexibility, replications of manualised evidence‐based programmes (EBP) may not achieve predictable outcomes due to differences in cultural priorities. In this case study, Families and Schools Together (FAST) was co‐produced with elders from a community of Hmong political refugees in the US Mid‐West. The paper aims to describe and evaluate the process of culturally adapting and implementing this universal parenting programme.
Design/methodology/approach
Observations of FAST groups to monitor programme integrity and notes on adaptation discussions were undertaken. Quantitative evaluations of parents in the first cohort (2 FAST groups) used a wait‐list control, randomised strategy, using three standardised instruments completed by the parents three different times. Data from five matched pairs of parent graduates (10) randomly assigned to “FAST now” or “FAST later” were analysed using one‐tailed, paired t‐tests.
Findings
Hmong parents and elders reported satisfaction on the cultural fit of FAST across the four groups, which graduated on average seven families each. Of 38 low‐income families who attended FAST once, 78 percent attended six or more sessions, in other words 22 percent dropped out. Parents reported statistically significant improvements in child anxiety (CBCL internalizing), child social skills (SSRS) and family adaptability (FACES II), with no changes in CBCL externalizing or family cohesion.
Originality/value
The paper provides a detailed study and evaluation of how an EBP can be successfully implemented with a highly socially marginalized group of immigrants in a Western society.
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Miklos A. Vasarhelyi, Michael G. Alles and Alexander Kogan
The advent of new enabling technologies and the surge in corporate scandals has combined to increase the supply, the demand, and the development of enabling technologies for a new…
Abstract
The advent of new enabling technologies and the surge in corporate scandals has combined to increase the supply, the demand, and the development of enabling technologies for a new system of continuous assurance and measurement. This paper positions continuous assurance (CA) as a methodology for the analytic monitoring of corporate business processes, taking advantage of the automation and integration of business processes brought about by information technologies. Continuous analytic monitoring-based assurance will change the objectives, timing, processes, tools, and outcomes of the assurance process.
The objectives of assurance will expand to encompass a wide set of qualitative and quantitative management reports. The nature of this assurance will be closer to supervisory activities and will involve intensive interchange with more of the firm s stakeholders than just its shareholders. The timing of the audit process will be very close to the event, automated, and will conform to the natural life cycle of the underlying business processes. The processes of assurance will change dramatically to being meta-supervisory in nature, intrusive with the potential of process interruption, and focusing on very different forms of evidential matter than the traditional audit. The tools of the audit will expand considerably with the emergence of major forms of new auditing methods relying heavily on an integrated set of automated information technology (IT) and analytical tools. These will include automatic confirmations (confirmatory extranets), control tags (transparent tagging) tools, continuity equations, and time-series cross-sectional analytics. Finally, the outcomes of the continuous assurance process will entail an expanded set of assurances, evergreen opinions, some future assurances, some improvement on control processes (through incorporating CA tests), and some improved data integrity.
A continuous audit is a methodology that enables independent auditors to provide written assurance on a subject matter, for which an entity’s management is responsible, using a series of auditors’ reports issued virtually simultaneously with, or a short period of time after, the occurrence of events underlying the subject matter.
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CICA/AICPA Research Study on Continuous Auditing (1999)
CICA/AICPA Research Study on Continuous Auditing (1999)
Companies must disclose certain information on a current basis.
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Corporate and Auditing Accountability, Responsibility, and Transparency (Sarbanes-Oxley) Act (2002)
Corporate and Auditing Accountability, Responsibility, and Transparency (Sarbanes-Oxley) Act (2002)
Roberto Outa, Fabio Roberto Chavarette, Vishnu Narayan Mishra, Aparecido C. Gonçalves, Luiz G.P. Roefero and Thiago C. Moro
In recent years, the mechanical industries began to apply many investments in research and technological development to obtain efficient methods to analyze the integrity of…
Abstract
Purpose
In recent years, the mechanical industries began to apply many investments in research and technological development to obtain efficient methods to analyze the integrity of structures and prevent disasters and/or accidents, ensuring people’s lives and preventing economic losses. Any structure, whether mechanical or aeronautical, before being put into use undergoes a structural integrity assessment and testing. In this case, non-destructive evaluations are performed, aiming to estimate the degree of safety and reliability of the structure. For this, there are techniques traditionally used such as ultrasonic inspection, X-ray, acoustic emission tests, among other techniques. The traditional techniques may even have a good instrumental apparatus and be well formulated for structural integrity assessment; however, these techniques cannot meet growing industrial needs, even more so when structures are in motion. The purpose of this paper is to demonstrate artificial immune systems (AISs), ate and strengthen the emergence of an innovative technological tool, the biological immune systems and AISs, and these are presented as computing methods in the field of structural health monitoring (SHM).
Design/methodology/approach
The concept of SHM is based on a fault detection mechanism used in industries, and in other applications, involving the observation of a structure or a mechanical system. This observation occurs through the dynamic response of periodic measurements, later related to the statistical analysis, determining the integrity of the system. This study aims to develop a methodology that identifies and classifies a signal in normal signals or in faults, using an algorithm based on artificial immunological systems, being the negative selection algorithm, and later, this algorithm classifies the failures in probabilities of failure and degree of fault severity. The results demonstrate that the proposed SHM is efficient and robust for prognosis and failure detection.
Findings
The present study aims to develop different fast access methodologies for the prognosis and detection of failures, classifying and judging the types of failures based on AISs. The authors declare that the present study was neither published in any other vehicle of scientific information nor is under consideration for publication in another scientific journal, and that this paper strictly followed the ethical procedures of research and publication as requested.
Originality/value
This study is original by the fact that conventional structural integrity monitoring methods need improvements, which intelligent computing techniques can satisfy. Intelligent techniques are tools inspired by natural and/or biological processes and belong to the field of computational intelligence. They present good results in problems of pattern recognition and diagnosis and thus can be adapted to solve problems of monitoring and identifying structural failures in mechanical and aeronautical engineering. Thus, the proposal of this study demonstrates and strengthens the emergence of an innovative technological tool, the biological immune system and the AIS, and these are presented as computation methods in the field of SHM in rotating systems – a topic not yet addressed in the literature.
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