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Partial alignment for 3 D point sets is a challenging problem for laser calibration and robot calibration due to the unbalance of data sets, especially when the overlap of data sets is low. Geometric features can promote the accuracy of alignment. However, the corresponding feature extraction methods are time consuming. The purpose of this paper is to find a framework for partial alignment by an adaptive trimmed strategy.

First, the authors propose an adaptive trimmed strategy based on point feature histograms (PFH) coding. Second, they obtain an initial transformation based on this partition, which improves the accuracy of the normal direction weighted trimmed iterative closest point (ICP) method. Third, they conduct a series of GPU parallel implementations for time efficiency.

The initial partition based on PFH feature improves the accuracy of the partial registration significantly. Moreover, the parallel GPU algorithms accelerate the alignment process.

This study is applicable to rigid transformation so far. It could be extended to non-rigid transformation.

In practice, point set alignment for calibration is a technique widely used in the fields of aircraft assembly, industry examination, simultaneous localization and mapping and surgery navigation.

Point set calibration is a building block in the field of intelligent manufacturing.

The contributions are as follows: first, the authors introduce a novel coarse alignment as an initial calibration by PFH descriptor similarity, which can be viewed as a coarse trimmed process by partitioning the data to the almost overlap part and the rest part; second, they reduce the computation time by GPU parallel coding during the acquisition of feature descriptor; finally, they use the weighted trimmed ICP method to refine the transformation.

After the novel coronavirus disease 2019 (COVID-19) was declared a pandemic by the World Health Organization in March 2020, its devastating effects began to be closely monitored all over the world. The new order that emerged due to the fight against the virus soon began to affect all our habits and behaviours. The fact that food consumption is vital for human well-being makes this an important area to investigate in terms of the impact of COVID-19. This research was carried out to investigate the changes in consumers' food consumption behaviour and habits during the COVID-19 pandemic and determine the factors that explain these changes.

In line with the recommendations for social distancing under pandemic conditions, the empirical data were collected via computer-assisted telephone interviewing (CATI). The participants were 1,023 individuals living in the major cities of the seven regions of Turkey. An ordered probit regression model was used to estimate the attitudes related to the changes in food consumption behaviour and habits, and descriptive statistics are provided to show the current food consumption and purchase situation.

The results showed that the changes in food consumption behaviour and habits due to the pandemic were related to price increase concerns, stockpiling, awareness of food waste, safety and excessive, food access concerns, natural/organic food preferences and packaging of foods. Moreover, the participants tended to prepare food at home and preferred food that was popular with other consumers. Consumers mainly bought food from discount stores and local grocery stores and consumed fresh vegetables and fruits, animal-based products, cereals and pulses.

The current study contributes to knowledge regarding the effects of the coronavirus pandemic on food consumption behaviour by using a predictive model and provides behavioural estimations by using a countrywide questionnaire. The results show that the pandemic affects food consumption routines and food perspective of consumers in various ways.

In the Norwegian offshore oil industry, helicopters have been used as a major mode of transporting personnel to and from offshore installations for decades. Helicopter transportation represents one of the major risks for offshore employees. The purpose of this paper is to study the safety of helicopter transportation in terms of the expected number of fatalities on an operational planning level.

Based on an analysis of helicopter accidents, this paper proposes a mathematical model that can aid in the planning of routes for the fleet in order to minimize the expected number of fatalities.

A theorem proven in this paper tells that hub-and-spoke configuration is the best way of routing helicopters in terms of minimizing expected number of fatalities. Computational results indicate that the expected number of fatalities may be reduced at the expense of longer travel time by implementing the proposed method into planning of routes for helicopter fleet.

The main limitation is the present inability to solve large problem instances.

The suggested tool is able to provide decision makers with a set of solutions from which they can choose the one with the best trade-off between travel time and transportation safety.

The mathematical model and theoretical results for route planning with a safety-based objective are original.

The main objective of safety instrumented systems (SISs) is to maintain a safe condition of a facility if hazardous events occur. However, in some cases, SIS's can be activated prematurely, these activations are characterized in terms of frequency by a Spurious Trip Rate (STR) and their occurrence leads to significant technical, economic and even environmental losses. This work aims to propose an approach to optimize the performances of the SIS by a multi-objective genetic algorithm. The optimization of SIS performances is performed using the multi-objective genetic algorithm by minimizing their probability of failure on demand PFDavg, Spurious Trip Rate (STR) and Life Cycle Costs (LCCavg). A set of constraints related to maintenance costs have been established. These constraints imply specific maintenance strategies which improve the SIS performances and minimize the technical, economic and environmental risks related to spurious shutdowns. Validation of such an approach is applied to an Emergency Shutdown (ESD) of the blower section of an industrial facility (RGTE- In Amenas).

The optimization of SIS performances is performed using the multi-objective genetic algorithm by minimizing their probability of failure on demand PFDavg, Spurious Trip Rate (STR) and Life Cycle Costs (LCCavg). A set of constraints related to maintenance costs have been established. These constraints imply specific maintenance strategies which improve the SIS performances and minimize the technical, economic and environmental risks related to spurious shutdowns. Validation of such an approach is applied to an Emergency Shutdown (ESD) of the blower section of an industrial facility (RGTE- In Amenas).

A case study concerning a safety instrumented system implemented in the RGTE facility has shown the great applicability of the proposed approach and the results are encouraging. The results show that the selection of a good maintenance strategy allows a very significant minimization of the PFDavg, the frequency of spurious trips and Life Cycle Costs of SIS.

The maintenance strategy defined by the system designer can be modified and improved during the operational phase, in particular safety systems. It constitutes one of the least expensive investment strategies for improving SIS performances. It has allowed a considerable minimization of the SIS life cycle costs; PFDavg and the frequency of spurious trips.

The National Health Service (NHS) Local Improvement Finance Trust (LIFT) programme was launched in 2001 as an innovative public‐private partnership to address the historical under‐investment in local primary care facilities in England. The organisations from the public and private sector that comprise a local LIFT partnership each have their own distinctive norms of behaviour and acceptable working practices – ultimately different organisational cultures. The purpose of this article is to assess the role of organisational culture in facilitating (or impeding) LIFT partnerships and to contribute to an understanding of how cultural diversity in public‐private partnerships is managed at the local level.

The approach taken was qualitative case studies, with data gathering comprising interviews and a review of background documentation in three LIFT companies purposefully sampled to represent a range of background factors. Elite interviews were also conducted with senior policy makers responsible for implementing LIFT policy at the national level.

Interpreting the data against a conceptual framework designed to assess approaches to managing strategic alliances, the authors identified a number of key differences in the values, working practices and cultures in public and private organisations that influenced the quality of joint working. On the whole, however, partners in the three LIFT companies appeared to be working well together, with neither side dominating the development of strategy. Differences in culture were being managed and accommodated as partnerships matured.

As LIFT develops and becomes the primary source of investment for managing, developing and channelling funding into regenerating the primary care infrastructure, further longitudinal work might examine how ongoing partnerships are working, and how changes in the cultures of public and private partners impact upon wider relationships within local health economies and shape the delivery of patient care.

To the authors’ knowledge this is the first study of the role of culture in mediating LIFT partnerships and the findings add to the evidence on public‐private partnerships in the NHS.

Introduces the fourth and final chapter of the ISEF 1999 Proceedings by stating electric and magnetic fields are influenced, in a reciprocal way, by thermal and mechanical fields. Looks at the coupling of fields in a device or a system as a prescribed effect. Points out that there are 12 contributions included ‐ covering magnetic levitation or induction heating, superconducting devices and possible effects to the human body due to electric impressed fields.

Households account for 27 per cent of the UK's total CO₂ emissions therefore addressing housing energy efficiency has become a priority. Low-zero carbon technologies (LZCTs) for both new-build and the existing housing stock are one mechanism to reduce CO₂. A gap in previous research into the subject was identified – the ongoing maintenance or “Asset Management” of LZCTs. This is important, inefficient or ineffective Asset Management may have a negative impact on the sustainability of energy efficient housing stock from a number of perspectives, including physical, social and economic. This paper aims to discuss these issues.

The research presents a sector based study of the English social housing sector with seven individual organisations (known as “Registered Social Landlords”) represented by senior Asset Management practitioners, providing the units of analysis. Semi-structured interviews were conducted to evaluate the past, current and future ability of the sector to successfully maintain LZCTs. The interviews were coded and a theme/sub-theme building process undertaken.

The interview analysis yielded three main themes (Asset Management Planning, Maintenance Skills and Occupier Impacts) and 12 sub-themes. Some of these confirmed findings from the literature review but others had not been previously located including inter-departmental conflicts and occupiers taking responsibility for maintenance.

A paucity of previous work specifically relating to Asset Management and LZCTs in the social housing sector was found. The findings should therefore be of interest to a wide range of stakeholders including registered providers, asset managers, surveyors, developers and policy makers.