The impact of Mean Time Between Disasters on inventory pre-positioning strategy

Purpose - This paper addresses the impact of Mean Time Between Disasters (MTBD) to inventory pre-positioning strategy of medical supplies prior to a sudden-onset disaster

Effects of dissipation on the superfluid-Mott-insulator transition of photons

We investigate the superfluid-Mott-insulator transition of a two-dimensional photon gas in a dye-filled optical microcavity and in the presence of a periodic potential. We show that in the random-phase approximation the effects of the dye molecules, which generally lead to dissipation in the photonic system, can be captured by two dimensionless parameters that only depend on dye-specific properties. Within the mean-field approximation, we demonstrate that one of these parameters decreases the size of the Mott lobes in the phase diagram. By considering also Gaussian fluctuations, we show that the coupling with the dye molecules results in a finite lifetime of the quasiparticle and quasihole excitations in the Mott lobes. Moreover, we show that there are number fluctuations in the Mott lobes even at zero temperature and therefore that the true Mott-insulating state never exists if the interactions with the dye are included.Comment: 13 pages, 7 figure

Mobile application supported urban-township e-grocery distribution

Purpose: The purpose of this paper is to present a mobile application supported townshipand urban e-grocery distribution models that uses a software application (app) to bridge the infrastructural barriers, costs and complexities associated with e-grocery delivery operations in rural township areas. Design/methodology/approach: Using a qualitative multi-case approach and semi-structured interviews, the study explored distribution practices of eight national emerging e-grocery retail businesses to demonstrate how mobile applications can facilitate South African urban and township e-grocery delivery models. Findings: The study reveals how the need to scale the use of new mobile application innovations fuels value-added services that power new e-grocery distribution models. Of interest is how the application aggregates demand rapidly, respond to demand within a short lead time and how e-grocers use competitors’ stores as their fulfilment centres. The use of apps reveals a slow transformation of society towards an inclusive model that integrates different types of workers in an informal context. Practical implications: The mobile application value-added service business model offers a new wave of scaling e-grocery retail to rural and township areas constrained by technological, economic and road infrastructure. The apps transcend e-grocery barriers and enables small businesses with limited resources to leverage e-grocery market opportunities that are unimaginable in townships and rural areas. Originality/value: The innovative mobile platform-base model offers emerging contextual insight of a pull e-grocery distribution model that demonstrates the supply chain innovations for addressing under-resource and under-developed logistics infrastructure

Hotspots of change in use of public transport to work: A geospatial mixed method study

Introduction: Several studies have supported the role of public transport in encouraging active transport through commuting. Investigating actual increases in public transport use within focussed local areas can help unravel what causes such increases. Methods: In this study, we investigated factors related to the increase in public transport use in focussed local areas (hotspots) through a geospatial mixed-method approach using data from South Western Sydney, Australia, spatial cluster detection, and local stakeholder interviews. We also examined areas with low levels of public transport use. Results: We found that while distance to train station is a significant predictor of usage, other important factors include the professional and socioeconomic profile of the neighbourhood around the train station, the train line's deemed attractiveness and parking availability. Conclusions: Thus, researchers and planners must consider a range of built environment factors when planning for changes that encourage public transport use. In addition, focusing on small local areas utilising geospatial mixed methods can provide important insights into the local drivers of public transport use

The politicisation of evaluation: constructing and contesting EU policy performance

Although systematic policy evaluation has been conducted for decades and has been growing strongly within the European Union (EU) institutions and in the member states, it remains largely underexplored in political science literatures. Extant work in political science and public policy typically focuses on elements such as agenda setting, policy shaping, decision making, or implementation rather than evaluation. Although individual pieces of research on evaluation in the EU have started to emerge, most often regarding policy “effectiveness” (one criterion among many in evaluation), a more structured approach is currently missing. This special issue aims to address this gap in political science by focusing on four key focal points: evaluation institutions (including rules and cultures), evaluation actors and interests (including competencies, power, roles and tasks), evaluation design (including research methods and theories, and their impact on policy design and legislation), and finally, evaluation purpose and use (including the relationships between discourse and scientific evidence, political attitudes and strategic use). The special issue considers how each of these elements contributes to an evolving governance system in the EU, where evaluation is playing an increasingly important role in decision making

Remote identification of the invasive tunicate Didemnum vexillum using reflectance spectroscopy

Benthic coverage of the invasive tunicate Didemnum vexillum on Georges Bank is largely unknown. Monitoring of D. vexillum coverage is vital to understanding the impact this invasive species will have on the productive fishing grounds of Georges Bank. Here we investigate using reflectance spectroscopy as a method for remote identification of D. vexillum. Using two different systems, a NightSea Dive-Spec and a combination of LED light sources with a hyperspectral radiometer, we collected in-situ measurements of reflectance from D. vexillum colonies. In comparison to reflectance spectra of other common benthic substrates, D. vexillum appears to have a unique spectral signature between 500 and 600 nm. Measuring the slope of the spectrum between these wavelengths appears to be the most robust method for spectral identification. Using derivative analysis or principal component analysis, the reflectance spectra of D. vexillum can be identified among numerous other spectra of common benthic substrates. An optical system consisting of a radiometer, light source, and camera was deployed on a remotely operated vehicle to test the feasibility of using reflectance to assess D. vexillum coverage. Preliminary results, analyzed here, prove the method to be successful for the areas we surveyed and open the way for its use on large-scale surveys