title: Used product acquisition, sorting and disposition for circular supply chains: Literature review and research directions

authors: Gunasekara, Lahiru

abstract: The vision of a circular economy (CE) inspires firms, governments, and scholars alike. The transition is underway in both practice and the literature, but success depends on the effective implementation of circular supply chains (CSCs), which encompass acquiring used products, sorting them by type and quality, and deciding which to dispose to various processing options. We review 131 high-impact journal articles on returns acquisition, sorting, and disposition (ASD) over the decade 2012–2021 to assess the current status of ASD research for CSCs and to discuss important research directions for supporting the transition to a CE. Uniquely synthesising the state of the art on all these three overarching decision areas, we find aspects of CSCs prominent in the decade's research agenda, such as closed loop supply chain coordination and ASD for remanufacturing, and highlight growing coverage of behavioural considerations. Research applicability has been constrained by a lack of empirical studies, limited practical validation of mathematical models, a focus on economic objectives, and restrictive modelling assumptions about behaviour and uncertainty in returns. We recommend further research in each part of ASD to facilitate a CSC, and as a whole, for transitioning to a CE. CE concepts such as joint decision-making between product design and returns management, cross-sector collaboration, and product-service systems should inform the agenda for CSC research.

text: Used product acquisition, sorting and disposition for circular supply chains: Literature review and research directions The vision of a circular economy (CE) inspires firms, governments, and scholars alike. The transition is underway in both practice and the literature, but success depends on the effective implementation of circular supply chains (CSCs), which encompass acquiring used products, sorting them by type and quality, and deciding which to dispose to various processing options. We review 131 high-impact journal articles on returns acquisition, sorting, and disposition (ASD) over the decade 2012–2021 to assess the current status of ASD research for CSCs and to discuss important research directions for supporting the transition to a CE. Uniquely synthesising the state of the art on all these three overarching decision areas, we find aspects of CSCs prominent in the decade's research agenda, such as closed loop supply chain coordination and ASD for remanufacturing, and highlight growing coverage of behavioural considerations. Research applicability has been constrained by a lack of empirical studies, limited practical validation of mathematical models, a focus on economic objectives, and restrictive modelling assumptions about behaviour and uncertainty in returns. We recommend further research in each part of ASD to facilitate a CSC, and as a whole, for transitioning to a CE. CE concepts such as joint decision-making between product design and returns management, cross-sector collaboration, and product-service systems should inform the agenda for CSC research.

year: 2023-06-01

title: The effect of AC magnetic  fields on liquid-metal free surfaces in industrialMHD.

authors: Spragg, Kirk John

subjects: MHD

abstract: In this thesis we investigate free-surface instabilities which occur in various
industrial processes involving liquid metal. Specifically, we examine a number
of simple problems with a view to developing a plausible theoretical description
based on MHD. Of particular interest is the behaviour of the free surface of a
pool of liquid metal when it is submitted to an alternating magnetic field.
  The first problem we examine considers the effect of a low-frequency mag-
netic field on a pool of liquid metal. An initially circular pool is deformed into
radially oscillating  starfish  modes at certain critical magnetic field strengths.
We study these azimuthal modes theoretically by investigating the behaviour
of an isolated mode. We also consider the influence of geometry in our studies
of a related problem invloving a rectangular  strip  of liquid metal. At certain
critical magnetic field strengths, an elongated pool is deformed into transverse
modes. Aside from complicated mode coupling, the behaviour of these trans-
verse modes is similar to the  starfish . Both the  starfish  and transverse
modes are caused by a Mathieu-type subharmonic instability.
  We next consider the effect of a medium-frequency magnetic field on an
initially circular pool of liquid metal. Experimentally we study the effect of
a vertical alternating medium-frequency magnetic field on an initially circular
pool. We observe two types of behaviour: slow radial oscillation of the pool
perimeter and rotation of the pool about its centre. The physics of this problem
are significantly more complicated than the  starfish  and  strip  problems.
Accordingly a description in terms of the previous theory is not possible.
  The final problem we consider is the effect of a high-frequency magnetic
field the surface of a conductor. Using a phase-field approach we consider two
simple problems: the first is to calculate the rest shape of an infinite strip
of liquid resting on a substrate in a vertical gravitational field; the second is
to calculate the equilibrium shape of the cross-section of a column of a liquid
conductor submitted to a high-frequency magnetic field whose field lines are
parallel far from the conductor. Our numeric solutions compare well with
previously known analytic solutions.

text: The effect of AC magnetic  fields on liquid-metal free surfaces in industrialMHD. In this thesis we investigate free-surface instabilities which occur in various
industrial processes involving liquid metal. Specifically, we examine a number
of simple problems with a view to developing a plausible theoretical description
based on MHD. Of particular interest is the behaviour of the free surface of a
pool of liquid metal when it is submitted to an alternating magnetic field.
  The first problem we examine considers the effect of a low-frequency mag-
netic field on a pool of liquid metal. An initially circular pool is deformed into
radially oscillating  starfish  modes at certain critical magnetic field strengths.
We study these azimuthal modes theoretically by investigating the behaviour
of an isolated mode. We also consider the influence of geometry in our studies
of a related problem invloving a rectangular  strip  of liquid metal. At certain
critical magnetic field strengths, an elongated pool is deformed into transverse
modes. Aside from complicated mode coupling, the behaviour of these trans-
verse modes is similar to the  starfish . Both the  starfish  and transverse
modes are caused by a Mathieu-type subharmonic instability.
  We next consider the effect of a medium-frequency magnetic field on an
initially circular pool of liquid metal. Experimentally we study the effect of
a vertical alternating medium-frequency magnetic field on an initially circular
pool. We observe two types of behaviour: slow radial oscillation of the pool
perimeter and rotation of the pool about its centre. The physics of this problem
are significantly more complicated than the  starfish  and  strip  problems.
Accordingly a description in terms of the previous theory is not possible.
  The final problem we consider is the effect of a high-frequency magnetic
field the surface of a conductor. Using a phase-field approach we consider two
simple problems: the first is to calculate the rest shape of an infinite strip
of liquid resting on a substrate in a vertical gravitational field; the second is
to calculate the equilibrium shape of the cross-section of a column of a liquid
conductor submitted to a high-frequency magnetic field whose field lines are
parallel far from the conductor. Our numeric solutions compare well with
previously known analytic solutions.

year: 2009

title: He Manu-Iri-i-te-Rangi - Bird of the Heavens: Tūrake Manuirirangi 1896 - 1969

authors: Manuirirangi, Hōri

abstract: Tūrake Manuirirangi was an influential tupuna of the Manuirirangi whānau. He was a devoted member of the Church of Jesus Christ of Latter-day Saints, and was instrumental in its establishment in the South Taranaki region. This chapter looks at his beliefs and leadership qualities within the Church, and within his hapū of Ngāti Tū, of Ngā Ruahine Iwi. The main focus here is to report on information collated from interviews, church records and Mormon missionary diaries.

text: He Manu-Iri-i-te-Rangi - Bird of the Heavens: Tūrake Manuirirangi 1896 - 1969 Tūrake Manuirirangi was an influential tupuna of the Manuirirangi whānau. He was a devoted member of the Church of Jesus Christ of Latter-day Saints, and was instrumental in its establishment in the South Taranaki region. This chapter looks at his beliefs and leadership qualities within the Church, and within his hapū of Ngāti Tū, of Ngā Ruahine Iwi. The main focus here is to report on information collated from interviews, church records and Mormon missionary diaries.

year: 2014