Multiplex PI-Control for Consensus in Networks of Heterogeneous Linear Agents

In this paper, we propose a multiplex proportional-integral approach, for solving consensus problems in networks of heterogeneous nodes dynamics affected by constant disturbances. The proportional and integral actions are deployed on two different layers across the network, each with its own topology. Sufficient conditions for convergence are derived that depend upon the structure of the network, the parameters characterizing the control layers and the node dynamics. The effectiveness of the theoretical results is illustrated using a power network model as a representative example.Comment: 13 pages, 6 Figures, Preprint submitted to Automatic

Homicidio y precios de la tierra: un análisis espacial en Santiago de Cali

Since 2000, Cali has had the highest mean annual homicide rate among the major Colombian cities. The model of Mills (1972) is extended to include the homicide per commune (from 2005 to 2012) as a measure of social distance, and to quantify the effect of this phenomenon on land prices (mean appraisals). Using an annual panel, the estimates of the model --- the family violence rate being the instrumental variable --- show that an increase in the homicide rate of one unit reduces the appraisals by 1.6%. One plausible interpretation is that homicides operate as a regressive tax on property wealth in Cali because it is more concentrated in the communes of the lower socio-economic stratum, systematically expanding the intra-urban social distanceDesde el año 2000 Cali tuvo la tasa promedio anual de homicidio más alta entre las principales ciudades colombianas. Nosotros ampliamos el modelo de Mills (1972), incluyendo el homicidio por comunas (durante 2005-2012) como medida de distancia social, para cuantificar el efecto de este fenómeno sobre los precios de la tierra (avalúos medios). Empleando datos panel, las estimaciones del modelo ---- usando la violencia familiar como variable instrumental ---- evidencian que un crecimiento unitario de la tasa de homicidio reduce los avalúos hasta en espacial un 1,6%. Una interpretación plausible es que el homicidio opera como un impuesto regresivo sobre la riqueza inmueble, pues en Cali se concentra más en las comunas de menor estrato socio económico, ampliando sistemáticamente la distancia social intraurbana

Modeling the Adoption of Identification Standards Within the Healthcare Supply Chain

The adoption of identification standards and its associated technology in the healthcare supply chain has been slow over the past twenty five years, despite the evidence of the benefits that can be achieved. The widespread use of identification standards in the form of barcode labeled medical products can contribute to the reduction of point of care errors and can increase the efficiency of healthcare supply chain related processes. This research is focused on the analysis of the adoption of identification standards in the healthcare supply chain with a particular focus on the healthcare provider adoption challenges. The research is divided into two phases. The first phase develops an extensive literature review on technology adoption with a particular focus on data standards. This adoption process is compared with the adoption of Electronic Health Records (EHR) and Electronic Data Interchange (EDI); main conclusions from the identification standards literature are presented, and a conceptual model to explain the identification-standards adoption process is proposed. The second phase proposes a model for identification standards adoption using a system dynamics modeling approach. The model builds on previous findings associated to the factors affecting identification standards adoption and relates the specific elements to the adoption rate via a causal loop diagram (CLD). The model is formulated in two stages. In the first stage, the Bass Diffusion Model (BDM) of technology adoption is adapted to simulate the adoption of identification standards supporting technologies. The second stage uses most of the factors defined in the CLD to develop a simulation model. A sensitivity analysis identifies relevant model parameters that facilitated the design of interventions to move the adoption process forward. Finally, the effects of some possible interventions are simulated using the validated model. The model provides an illustration of the use of system dynamics models and diffusion theory to understand an important policy problem reported in the literature and not yet solved. Also this research informs real world practitioners and the academic community on issues like the lack of data and other challenging aspects of empirical research that can be addressed with the proposed model and methodology