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1 – 10 of over 38000Daniel Roger and Ewa Napieralska-Juszczak
High-temperature (HT°) motors are made with inorganic coils wound with a ceramic-coated wire. They must be carefully designed because the HT° insulating materials have a lower…
Abstract
Purpose
High-temperature (HT°) motors are made with inorganic coils wound with a ceramic-coated wire. They must be carefully designed because the HT° insulating materials have a lower breakdown voltages than the polymers used for insulating standard machines.
Design/methodology/approach
The voltage distribution between stator coils is computed with high-frequency (HF) equivalent circuits that consider the magnetic couplings and the stray capacitances. Two time scales are used for getting a fast computation of very short voltage spikes. For the first step, a medium time scale analysis is performed considering a simplified equivalent circuit made without any stray capacitance but with the full PWM pattern and the magnetic couplings. For the second step, a more detailed HF equivalent circuit computes voltage spikes during short critical time windows.
Findings
The computation made during the first step provides the critical time windows and the initial values of the state variables to the second one. The rise and fall time of the electronic switches have a minor influence on the maximum voltage stress. Conversely, the connection cable length and the common-mode capacitances have a large influence.
Research limitations/implications
HF equivalent circuits cannot be used with random windings but only to formed coils that have a deterministic position of turns.
Practical implications
The proposed method can be used designing of HT° machine windings fed by PWM inverter and for improving the coils of standard machine used in aircraft’s low-pressure environments.
Originality/value
The influence of grounding system of the DC link is considered for computing the voltage spikes in the motor windings.
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Investigates the differences in protocols between arbitral tribunals and courts, with particular emphasis on US, Greek and English law. Gives examples of each country and its way…
Abstract
Investigates the differences in protocols between arbitral tribunals and courts, with particular emphasis on US, Greek and English law. Gives examples of each country and its way of using the law in specific circumstances, and shows the variations therein. Sums up that arbitration is much the better way to gok as it avoids delays and expenses, plus the vexation/frustration of normal litigation. Concludes that the US and Greek constitutions and common law tradition in England appear to allow involved parties to choose their own judge, who can thus be an arbitrator. Discusses e‐commerce and speculates on this for the future.
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Fabiana Bugs Antocheviz, Caroline Arsego and Antônio Tarcísio Reis
This paper aims to examine the effects of transformations of the levels of visual and functional permeability and the types of uses on the ground floors of buildings on the…
Abstract
Purpose
This paper aims to examine the effects of transformations of the levels of visual and functional permeability and the types of uses on the ground floors of buildings on the perception of security and the occurrence of residential burglary, theft in residence, pedestrian mugging, vehicle robbery, vehicle theft and theft of items inside a vehicle on selected blocks.
Design/methodology/approach
Nine blocks divided into three groups were selected in Capão da Canoa, a Brazilian city that has been undergoing morphological transformations, including the replacement of buildings with residences and shops on the ground floor, with doors and windows facing the street, by buildings with a predominance of garage doors and blind walls on the ground floors. Data were collected through the application of questionnaires and interviews.
Findings
The results reveal, for example, that perception of greater security is related to the blocks with a greater number of functional and visual connections between the ground floor interfaces of the buildings and the open public spaces. In addition, the night period records the higher number of criminal occurrences, even on blocks with higher rates of visual and functional connections between the ground floor interfaces and the public open space and higher rates of residential and commercial uses on the ground floor of the buildings.
Originality/value
It is expected that the results of this paper will allow for greater knowledge and the revision of many urban guidelines regarding the effects of the transformations of ground floor interfaces from traditional to contemporary buildings in the perception of security and the occurrence of crimes in public open spaces and in neighbouring residential units. It is further evidenced the need to recognize the ground floor interface as an element of public interest, even if it belongs to a private property. Nonetheless, further research is needed on the relationships between the quantifications of the levels of visual and functional permeability, the different types of uses on the ground floor of buildings, movement of people and crimes in open spaces and buildings in different periods of the day.
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Introducing the concept of a design domain to truss topology optimization, this paper presents an algorithm generating geometrically admissible ground structures on possibly…
Abstract
Introducing the concept of a design domain to truss topology optimization, this paper presents an algorithm generating geometrically admissible ground structures on possibly concave (or even disconnected) 3D design domains. That is a set of connections between nodal points actually respecting the geometry of the design domain. Since ground structures may be applied in other contexts the presentation does not assume any specifics of truss topology optimization. However, in the example section an application of ground structures in a truss topology optimization problem may be found.
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Knight's Industrial Law Reports goes into a new style and format as Managerial Law This issue of KILR is restyled Managerial Law and it now appears on a continuous updating basis…
Abstract
Knight's Industrial Law Reports goes into a new style and format as Managerial Law This issue of KILR is restyled Managerial Law and it now appears on a continuous updating basis rather than as a monthly routine affair.
In order to succeed in an action under the Equal Pay Act 1970, should the woman and the man be employed by the same employer on like work at the same time or would the woman still…
Abstract
In order to succeed in an action under the Equal Pay Act 1970, should the woman and the man be employed by the same employer on like work at the same time or would the woman still be covered by the Act if she were employed on like work in succession to the man? This is the question which had to be solved in Macarthys Ltd v. Smith. Unfortunately it was not. Their Lordships interpreted the relevant section in different ways and since Article 119 of the Treaty of Rome was also subject to different interpretations, the case has been referred to the European Court of Justice.
The Equal Pay Act 1970 (which came into operation on 29 December 1975) provides for an “equality clause” to be written into all contracts of employment. S.1(2) (a) of the 1970 Act…
Abstract
The Equal Pay Act 1970 (which came into operation on 29 December 1975) provides for an “equality clause” to be written into all contracts of employment. S.1(2) (a) of the 1970 Act (which has been amended by the Sex Discrimination Act 1975) provides:
M.K. Loganathan and O.P. Gandhi
Reliability assessment does require an effective structural modelling approach for systems, in general and manufacturing systems are no exception. This paper aims to develop it…
Abstract
Purpose
Reliability assessment does require an effective structural modelling approach for systems, in general and manufacturing systems are no exception. This paper aims to develop it for large manufacturing systems using graph models, a systems approach.
Design/methodology/approach
Structural graph models for reliability at various hierarchical levels are developed by considering a CNC cam shaft grinding machine. The system reliability expression is obtained by converting the reliability graphs into equivalent matrices, which helps to evaluate and analyse system.
Findings
Using the obtained reliability expressions at various hierarchical levels of the system, it is possible not only to evaluate its reliability from structure point of view but also to identify weak structural elements from reliability point of view.
Research limitations/implications
The approach can be extended to include the influence of other parameters, such as human, component and environment, etc., on the system reliability.
Practical implications
The approach helps to design and develop manufacturing systems from reliability consideration by assessing their possible alternatives among these.
Originality/value
The suggested methodology is useful for reliability evaluation of large and complex manufacturing systems.
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