Building a boundaryless manufacturing organisation through HITOP method

There is little empirical research to support the allegation that ‘leagile’ manufacturing organisations thrive in hostile environments, nor has it been demonstrated that organisation processes (referred to as enablers) actually support ‘leagile’ performance. This study tests the statistical significance of five selected HITOP (highly integrated technology, organisation and people) ‘leagile’ enablers. This was accomplished by using a mail survey instrument to measure the presence of ‘leagile enablers’ in a sample of companies taken from best factory award winners in UK, US and Japan. [Continues.

Data-driven Piecewise Affine Decision Rules for Stochastic Programming with Covariate Information

Focusing on stochastic programming (SP) with covariate information, this paper proposes an empirical risk minimization (ERM) method embedded within a nonconvex piecewise affine decision rule (PADR), which aims to learn the direct mapping from features to optimal decisions. We establish the nonasymptotic consistency result of our PADR-based ERM model for unconstrained problems and asymptotic consistency result for constrained ones. To solve the nonconvex and nondifferentiable ERM problem, we develop an enhanced stochastic majorization-minimization algorithm and establish the asymptotic convergence to (composite strong) directional stationarity along with complexity analysis. We show that the proposed PADR-based ERM method applies to a broad class of nonconvex SP problems with theoretical consistency guarantees and computational tractability. Our numerical study demonstrates the superior performance of PADR-based ERM methods compared to state-of-the-art approaches under various settings, with significantly lower costs, less computation time, and robustness to feature dimensions and nonlinearity of the underlying dependency

Import demand under price and exchange-rate uncertainties: The case of U.S. Atlantic salmon imports

This study investigates the impacts of price and exchange rate volatilities on Atlantic salmon imports in the U.S. market. We first derive an extended Rotterdam demand model, revealing how risk factors affect import demand through ‘adjusted’ prices. For example, the theoretical model shows that risk-averse importers add risk premiums as a markup for the cost of risk factors. Moreover, the trade effect of volatility variables depends on own-price elasticities and the degree of substitutability between competing products. Our empirical results reveal that U.S. salmon importers are sensitive to price and exchange rate volatilities; however, these two risk factors have differing impacts on import demand, implying the necessity (or effect) of hedging strategies.publishedVersio

The role of collective motion in the ultrafast charge transfer in van der Waals heterostructures.

The success of van der Waals heterostructures made of graphene, metal dichalcogenides and other layered materials, hinges on the understanding of charge transfer across the interface as the foundation for new device concepts and applications. In contrast to conventional heterostructures, where a strong interfacial coupling is essential to charge transfer, recent experimental findings indicate that van der Waals heterostructues can exhibit ultrafast charge transfer despite the weak binding of these heterostructures. Here we find, using time-dependent density functional theory molecular dynamics, that the collective motion of excitons at the interface leads to plasma oscillations associated with optical excitation. By constructing a simple model of the van der Waals heterostructure, we show that there exists an unexpected criticality of the oscillations, yielding rapid charge transfer across the interface. Application to the MoS2/WS2 heterostructure yields good agreement with experiments, indicating near complete charge transfer within a timescale of 100 fs