Modification of the optical reflectance spectra of epitaxial gallium arsenide by weak magnetic fields J. Appl. Phys. 112, 073513 (2012) Theoretical and experimental study of the optical absorption at longitudinal phonon or phonon-plasmon coupling mode energy: An example of GaN J. Appl. Phys. 112, 063531 (2012) Negative differential resistance associated with hot phonons J. Appl. Phys. 112, 063707 (2012) Photoluminescence properties and high resolution x-ray diffraction investigation of BInGaAs/GaAs grown by the metalorganic vapour phase epitaxy method J. Appl. Phys. 112, 063109 (2012) Optical properties of InGaPN epilayer with low nitrogen content grown by molecular beam epitaxy

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Purpose -This paper sets out to present a reappraisal on advanced planning and scheduling (APS) systems in industrial settings and propose an effective approach for APS implementation. Design/methodology/approach -A case study approach is adopted, and a research framework comprising human-, technological-, and organizational-dimensions is developed to analyze the evidence database which includes business flows, system design documents, archival records, post-system assessment, participant-observation and semi-structured interviews. Findings -The findings indicate that real-world production planning problems are ill-defined, complex and dynamic. A post-implementation evaluation reveals major pitfalls in the technology-dominant approach, whose negative ramifications are usually overlooked. Besides, these APS implementation pitfalls are found to be attributable to the real-world context, human factors and organizational aspects. Research limitations/implications -Despite advances in information technology (IT) and computer modeling techniques, humans still play critical roles in the production-planning processesespecially in a complex and dynamic manufacturing environment where incomplete, ambiguous, inconsistent and untimely data make automatic planning unrealistic. A rational human-computer collaboration scheme under an effective organizational structure would be in a better position to take advantage of the IT. Originality/value -This paper presents a humans-technology-organization-framework of real planning systems, which is employed to analyze a case of APS implementation. Practical insights are extracted as a result of this field research, and a realist approach is proposed to cope with the problems and pitfalls of APS implementation in industrial settings.

Photoluminescence spectra of cubic GaN grown on a GaAs substrate by molecular beam epitaxy have been studied as a function of hydrostatic pressure at 10 K. The spectra are abundant in emission structures arising from a variety of radiative recombination processes, such as free-electron–bound-hole and donor-acceptor pair transitions. These emission peaks shift to higher energy with increasing pressure, providing a measure of the pressure coefficient of the band gap of cubic GaN. In addition, a spectral feature, which is superimposed on the other emission peaks and not observable at atmospheric pressure, becomes gradually resolvable as pressure increases. The difference of pressure dependence of this emission from the others suggests that it is associated with a deep center.

Time-resolved photoluminescence has been employed to study the donor-acceptor pair recombination kinetics of the yellow (∼2.3 eV) and blue (∼2.8 eV) luminescence bands in Si- and Mg-doped GaN layers, respectively. As the Si doping concentration in Si-doped GaN increases, the lifetime τ1/e of the yellow luminescence decreases, indicating that a shallow Si donor is the origin of the yellow luminescence. The blue luminescence is most likely due to a shallow Mg acceptor and a deep donor composed of a Mg acceptor-nitrogen vacancy complex, as seen by the independence of τ1/e on the Mg concentration measured by secondary ion mass spectroscopy in the range (2.5–6.0)×1019 cm−3. As the temperature is increased from 10 to 300 K, the lifetimes for the yellow and blue luminescence remain nearly constant, indicating that the distribution of electrons and holes bound to donors and acceptors does not change much with increasing temperature.

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The purpose of this paper is to find a better B2C environment through collecting what information and supporting interfaces are provided on current B2C web sites. We build a checklist based on the framework of B2C consumer behavior model and used it to evaluate current B2C web sites among three categories: purchasing process, types of products, and the source of web sites. The results indicated that poor information or supporting interface design was provided on web sites during the “evaluating and comparing” process. More information or supporting interface design was provided on the internet bookstore, less information or supporting interface design was provided on web sites that sell tickets and flowers. The local web sites provided more information or supporting interface design than international web sites. The results also showed that the difference is highly significant.