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More than 33 million passenger cars were produced worldwide in 1987, 4.3 million of which were ‘Made in Germany’. In Germany the industry has taken the lead in recognising the importance of logistics for future competitiveness. Stefan Schmidt of BMW reviews the development of JIT in Japan and discusses its application in the automotive industry in the USA. He also presents the concept of materials supply at BMW and future developments in logistics.

The purpose of this paper is to introduce a new arc-length control method for physically non-linear problems based on the rates of the internal and the dissipated energy.

In this paper, the authors derive from the second law of thermodynamics the arc-length method based on the rate of the dissipated energy and from the time derivative of the energy density the arc-length method based on the rate of the internal energy.

The method requires only two parameters and can automatically trace equilibrium paths which display multiple snap-through and/or snap-back phenomena.

A fully energy-based control procedure is developed, which facilitates switching between dissipative and non-dissipative arc-length control equations in a natural way. The method is applied to a plate with an eccentric hole using the phase field model for brittle fracture and to a perforated beam using interface elements with decohesion.

The purpose of this paper is to understand determinants of food waste through analysing patterns of practices including shopping, planning, consumption of leftovers and attitudes around best-before dates.

A survey and waste composition analysis of 142 households was conducted in the City of Toronto. Bivariate analyses and confirmatory factor analysis (CFA) using a structural equation model were used to identify relationships between per capita food waste, household socio-demographic characteristics and household food practices.

Constructs related to planning practices and best-before date practices were identified through the CFA. Household size and the best-before construct were negatively correlated with per capita food waste. The planning construct had no correlation, which may be attributed to the influence of the retail environment in encouraging unplanned purchases. The best-before construct was significantly correlated with the presence of children in the home, an indicator of the compromises that parents make in domestic provisioning to ensure healthy foods for their children, such as more caution in handling items after their best-before dates.

This is the first study of its kind that uses directly measured per capita food waste from a waste composition study in a structural equation model with a construct related to best-before dates to determine drivers of food waste. It is also the first to find that children in the home can have an indirect influence on food waste through the household's best-before practices.

The trend in the automotive industry is towards highly differentiated production of small lots. The authors discuss (optimising the supply and positioning of material for car assembly.)

The use of explicit finite difference schemes for low Stefan number problems with moving interface was largely abandoned because they require small time intervals (large CPU time) to obtain accurate non‐oscillatory solutions. This paper uses these type of schemes for better estimations of the dynamics of the solid—liquid interface. The scheme in which time and radial intervals are constant, uses a local, continuous, time‐dependent radial coordinate to define the instantaneous location of the interface. Taylor series expansions which result in a polynomial fit are used for forward and backward interpolation of temperatures of nodal points in the vicinity of the interface. A distinction is made between the left and right position of the interface relative to the closest nodal point. The algorithm handles accurately and effectively the non‐linearities near the interface thus producing accurate stable solutions with relatively low CPU time. The scheme which obviously may be applied to large Stefan number problems, is also suitable for time dependent boundary conditions as well as temperature dependent physical properties. The results obtained by the scheme were in excellent agreement with ones derived from an approximate analytical solution which is applicable in the low Stefan number range.

This article reports the results from a panel discussion held at the 2019 European Conference on Information Systems (ECIS) on the use of technology-based autonomous agents in collaborative work.

The panelists (Drs Izak Benbasat, Paul Benjamin Lowry, Stefan Morana, and Stefan Seidel) presented ideas related to affective and cognitive implications of using autonomous technology-based agents in terms of (1) emotional connection with these agents, (2) decision-making, and (3) knowledge and learning in settings with autonomous agents. These ideas provided the basis for a moderated panel discussion (the moderators were Drs Isabella Seeber and Lena Waizenegger), during which the initial position statements were elaborated on and additional issues were raised.

Through the discussion, a set of additional issues were identified. These issues related to (1) the design of autonomous technology-based agents in terms of human–machine workplace configurations, as well as transparency and explainability, and (2) the unintended consequences of using autonomous technology-based agents in terms of de-evolution of social interaction, prioritization of machine teammates, psychological health, and biased algorithms.

Key issues related to the affective and cognitive implications of using autonomous technology-based agents, design issues, and unintended consequences highlight key contemporary research challenges that allow researchers in this area to leverage compelling questions that can guide further research in this field.

A method has been developed for the solution of inverse heat diffusion problems to find the initial condition, boundary condition, and the source and sink function in the heat diffusion equation. The method has been used in the development of a source‐and‐sink method to find the boundary conditions in inverse Stefan problems. Green's functions have been used in the solution, and the problems are solved by using two approaches: a series solution approach, and a time incremental approach. Both can be used to find the boundary conditions without reliance on the flux information to be supplied at both sides of the interface. The methods are efficient in that they require less equations to be solved for the conditions. The numerical results have shown to be accurate, convergent, and stable. Most of all, the results do not degrade with time as in other time marching schemes reported in the literature. Algorithms can also be easily developed for the solution of the conditions.

This paper aims to examine how collaborative supplier development (SD) activities, supplier capabilities and buyer–supplier relationship interrelate in technology-based, luxury product business contexts characterized by small volumes, difficult targets and resource constraints relative to those targets.

Using inductive case research method, the authors investigate multiple embedded cases involving six dyadic buyer–supplier relationships of two luxury product manufacturers in the motorcycle and automotive industries. Each dyad represents an important sub-system for which the buying firm committed significant SD efforts to help the supplier successfully achieve difficult targets.

The analysis reveals how paradoxical tensions might emerge as the firms engage in successful SD activities, which could lead to decreasing relationship commitment ultimately resulting in the termination of the relationship. The authors utilize the “value co-creation and value capture” paradox framework to understand the SD and relationship dynamic and characterize it as developing-leveraging paradox to explain its dualities, i.e. commitment-based SD efforts (increasing value co-creation), and unilateral leveraging of the newly acquired capabilities (increasing value capture) by both the buyer and the supplier. Overemphasis on value capture by one of the exchange partners spurs a detrimental vicious cycle leading to the decline of the relationship.

The study explains the paradoxical dynamics that may emerge in SD activities of innovative, technologically complex, luxury product firms. The findings contribute to the SD literature by highlighting how learnings from SD activities could contribute to the dark sides of buyer–supplier relationship. The technologically complex, luxury product contextual characteristics of the study may limit the generalizability of the study findings.

The study provides novel insights into the emergence and management of paradoxes in buyer–supplier relationships, in terms of virtuous and vicious dynamics of developing-leveraging.

To examine the heat transfer characteristics of soild‐liquid phase change material (PCM) suspensions in a rectangular natural circulation loop.

A continuum mixture flow model is used for the buoyancy‐driven circulation flow of the PCM suspensions together with an approximate enthalpy model to describe the solid‐liquid phase change (melting/freezing) process of the PC particles in the loop. Numerical simulations via a finite difference method have been conducted for the pertinent physical parameters of a loop with fixed geometrical configuration in the following ranges: the modified Rayleigh number Ra*=10⁹‐10¹³, the modified Stefan number Ste*=0.05‐0.5, the particle volumetric fraction C_v=0‐20 percent and the modified subcooling factor Sb*=0‐2.0.

The melting/freezing processes of the PCM particles at the heated/cooled sections of the loop are closely interrelated in their inlet conditions of the suspension. The influences of the modified Rayleigh number, the particle fraction, the modified Stefan number, and the modified subcooling factor on the heat transfer behavior, as well as the thermal efficacy of the PCM suspensions are elucidated. There could be a flow regime in the parametirc domain where heat transfer performance of the suspension circulation loop is significantly enhanced, due to contribution of the latent heat transport associated with melting/freezing of PCM particles.

Future work to address effects of the geometric parameters such as the aspect ratio; the lengths and locations of, as well as the relative height between the heated and cooled sections is definitely needed, which are necessary steps towards developing more reliable predictive tools for system design of a circulation loop containing PCM suspension.

This work has explored the feasibility and quantified the efficacy of incorporating the PC suspensions as the heat transfer enhancement medium in a natural circulation loop, which has not been examined previously.