Andreas Ruf, Michael Schröder, Aryanti Kusuma Putri, Roman Konrad, David Franck and Kay Hameyer
The purpose of this paper is to focus on the mechanical bearing load caused by the unbalanced magnetic pull (UMP), which is studied in detail. The applied approach is based on an…
Abstract
Purpose
The purpose of this paper is to focus on the mechanical bearing load caused by the unbalanced magnetic pull (UMP), which is studied in detail. The applied approach is based on an analysis of static and dynamic eccentricities at different positions and different amplitudes. The influence of the operating points is calculated to show the effective bearing load for machines operating at different speeds. The decreasing lifetime of the applied bearings is examined and evaluated in detail.
Design/methodology/approach
To evaluate the proposed methodology a permanent magnet synchronous machine (PMSM) with buried magnets is used. To consider effects of slotting and saturation, a finite element (FE) model is employed. The Monte Carlo method is used to determine the most likely amplitudes of the eccentricities. Calculating the UMP for all possible operating points using a control strategy for the machine and coupling this results with a drive cycle, determines the effective force acting on the bearing.
Findings
It has been shown that the position of the eccentricity has a not significant influence on the behavior of the UMP and may therefore be neglected. The amplitude of the eccentricity vector influences the amplitude of the UMP including all harmonic force components. For technical relevant eccentricities, the influence is approximately linear for the average and the dominant harmonics of the UMP. In most cases, it is sufficient to displace the rotor at an arbitrary position and amplitude. It is sufficient to simulate one type of eccentricity (static or dynamic) with an arbitrary value of displacement (rotor or stator) to evaluate all possible airgap unbalances. Using stochastic simulations of the eccentricity amplitudes enables an a priori design and lifetime estimation of bearings.
Originality/value
This paper gives a close insight on the effect of mechanical bearing load caused by rotor eccentricities. The effect of the position of the eccentricity vector, the operational range and a drive cycle are considered. A stochastic simulation and an empirical lifetime model of one bearing gives an example of using this methodological approach.
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National Library Week was first launched in America in the spring of 1958 with the slogan “Wake Up and Read”. It is now an established, continuing, year‐round programme to help…
Abstract
National Library Week was first launched in America in the spring of 1958 with the slogan “Wake Up and Read”. It is now an established, continuing, year‐round programme to help build a reading nation and to spur the use and improvement of libraries of all kinds. The sponsors seek the achievement of these objectives because they are the means of serving social and individual purposes that are immeasurably larger.
NATIONAL Library Week was first launched in America in the spring of 1958 with the slogan “Wake Up and Read”. It is now an established, continuing, year‐round programme to help…
Abstract
NATIONAL Library Week was first launched in America in the spring of 1958 with the slogan “Wake Up and Read”. It is now an established, continuing, year‐round programme to help build a reading nation and to spur the use and improvement of libraries of all kinds. The sponsors seek the achievement of these objectives because they are the means of serving social and individual purposes that are immeasurably larger.
PAULA F. SILVER and ROBERT HESS
This paper reports the findings of an exploratory, small sample, one institution study designed to assess the value of process‐oriented theory coursework in enhancing students’…
Abstract
This paper reports the findings of an exploratory, small sample, one institution study designed to assess the value of process‐oriented theory coursework in enhancing students’ conceptual complexity. The study is based on conceptual systems theory which acknowledges that there are considerable differences among individuals in their abilities to process information in their social environments. The authors conclude tentatively from the study that process‐oriented theory coursework does affect students' conceptual complexity. For example, those who formally studied organization theory generally make more differentiations among constructs than do other students; similarly, they scored higher on a general measure of integrative complexity.
Deborah Mifsud, Maria Attard and Stephen Ison
Old age is a complex and dynamic phenomenon. The relationship between old age and transport is also very complex due to the heterogeneity within this age group. Yet what is…
Abstract
Old age is a complex and dynamic phenomenon. The relationship between old age and transport is also very complex due to the heterogeneity within this age group. Yet what is certain is that with age, a person’s functional abilities change. This chapter provides a summary of how older people can be vulnerable within the road environment. Using an established framework for understanding old-age vulnerabilities, this chapter explains the common exposure factors and threats that several older people face in the transport environment. These primarily deal with individual physical and cognitive characteristics, medical conditions as well as the appropriateness (or not) of infrastructure. Subsequently, common difficulties for older drivers, pedestrians and public transport users are discussed. The main vulnerabilities that result from such difficulties are related to an over-representation of older people in accidents and to a lower quality of life due to mobility inefficiencies. Yet, using the same framework, the compensation techniques that older people often adopt to minimise such limitations are also highlighted. Reference is also made to the issues related to the lack of awareness in old age and the corresponding inability to compensate. The review concludes by suggesting a way forward for further studies on transport vulnerability in later life.
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Magda Boere-Boonekamp, Karin Groothuis-Oudshoorn, Tamara Schloemer, Peter Schröder-Bäck, Janine van Til, Kinga Zdunek and Paul Kocken
Identifying the qualities of primary care that have the potential to produce optimal health outcomes is only half the story. The Models of Child Health Appraised (MOCHA) project…
Abstract
Identifying the qualities of primary care that have the potential to produce optimal health outcomes is only half the story. The Models of Child Health Appraised (MOCHA) project has not only explored how to transfer these to other national contexts, but also which successful components should be transferred. It is important to assess the population criteria of the identified sociodemographic, cultural and social characteristics and the population perspectives on a care system’s components. The project analysed public experiences and perceptions of the quality of primary care for children from a representative sample of the general public in five European Union member states. The public perception of children’s primary care services, in particular the perceived quality of care and expectations with regard to care for children, is important to understand before MOCHA lessons can be effectively adopted in a country. We found that the socio-cultural characteristics of a country inform the population perceptions and preferences with regard to the care system. In the five countries surveyed, there was agreement about aspects of quality of care – such as accessible opening hours, confidential consultations for children and timeliness of consultation for an illness, but there was a difference in opinion about giving priority to items such as making an appointment without a referral, or a child’s right to a confidential consultation. The cultural context of transferability and the means of addressing this such as defining the target audience and the different means of disseminating important messages to the wider community to address contextual factors can act as barriers or facilitators to the introduction of new components of primary care models.
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R.D. Kulkarni, M.E. Chaudhari and S. Mishra
The purpose of this paper is to provide a critical and in‐depth review of the present status and recent developments in synthetic methodologies, reaction engineering, process…
Abstract
Purpose
The purpose of this paper is to provide a critical and in‐depth review of the present status and recent developments in synthetic methodologies, reaction engineering, process design and quality control aspects associated with the manufacture of mono and multifunctional acrylate monomers.
Design/methodology/approach
This paper reviews commercially important UV cure mono and multifunctional acrylate monomers. It covers their synthesis, catalyst, and appropriate solvents for azeotropic removal of byproducts. The detail discussion on catalysis, basis of design of reactors and commercial plant and the process engineering associated with the manufacture has been supported through citation of synthesis of various acrylate monomers. The methodologies adopted for determination of physical, chemical and compositional characterisation of acrylate monomers have been presented. In addition, the guidelines regarding the bulk storage and commercial handling of acrylates have been reviewed.
Findings
The reaction engineering of esterification reaction between acrylic acid and polyol has been worked out to provide the basis for selection of reactors. The reaction has been modeled as a series – parallel complex reaction for providing explanation for generation of various byproducts/adducts and multiple esters.
Practical implications
The detailed discussion on formation, characterisation and treatment of Michael adducts and purification of acrylate monomers will be relevant for new researchers for further development. A review of guidelines on selection of homogenous and heterogeneous catalysts for synthesis of acrylate monomers has been presented.
Originality/value
Since the related literature on acrylate monomers is scarce, scattered and proprietary, the consolidated coverage in one paper will be useful.
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Kinga Zdunek, Michael Rigby, Shalmali Deshpande and Denise Alexander
The child is at the centre of all Models of Child Health Appraised research and indeed all primary care delivery for children. Appraising models of primary care for children is…
Abstract
The child is at the centre of all Models of Child Health Appraised research and indeed all primary care delivery for children. Appraising models of primary care for children is incomplete without ensuring that experiences of primary care, design, treatment, management and outcomes are optimal for the child. However, the principle of child centricity is not implicit in many healthcare systems and in many aspects of life, yet it is extremely important for optimal child health service design and child health. By exploring the changing concept of ‘childhood’, we understand better the emergence of the current attitude towards children and their role in today’s Europe and the evolution of child rights. Understanding child centricity, and the role of agents acting on behalf of the child, allows us to identify features of children’s primary care systems that uphold the rights of a child to optimum health. This is placed against the legal commitments made by the countries of the European Union and European Economic Area to ensure that children’s rights are respected.
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Deutsche Bank (DB) is using project‐orientated learning, new technology and academic input as part of a radical transformation of its HR function. In 1999, after acquiring Bankers…
Abstract
Deutsche Bank (DB) is using project‐orientated learning, new technology and academic input as part of a radical transformation of its HR function. In 1999, after acquiring Bankers Trust, DB had more than 90,000 employees at five globally‐operating business divisions and a corporate center, and had customers in 68 countries. In response to the demands of a new economy and an environment of continuous change, DB decided that its HR function should play a more strategic and value‐creating role in the business.