A systems approach to characterise the dissemination process of household water treatment systems in developing countries

Abstract: Starting in the 1980s, household-level water treatment and safe storage systems (HWTS) have been developed as simple, local, user-friendly, and low cost options to improve drinking water quality at the point of use. However, despite conclusive evidence of the health and economic benefits of HWTS, and promotion efforts in over 50 countries in the past 20 years, implementation outcomes have been slow, reaching only 5-10 million regular users. This study attempts to understand the barriers and drivers affecting HWTS implementation. Although existing literature related to HWTS and innovation diffusion theories proposed ample critical factors and recommendations, there is a lack of holistic and systemic approach to integrate these findings. It is proposed that system dynamics modelling can be a promising tool to map the inter-relationships of different critical factors and to understand the structure of HWTS dissemination process, which may lead to identifying high impact, leveraged mitigation strategies to scale-up HWTS adoption and sustained use.

A rhetorical approach to IT diffusion: reconceptualizing the ideology-framing relationship in computerization movements

In this paper we propose rhetoric as a valuable yet underdeveloped alternative paradigm for examining IT diffusion. Building on recent developments of computerization movements theory, our rhetorical approach proposes that two central elements of the theory, framing and ideology, rather than being treated as separate can be usefully integrated. We suggest that IT diffusion can be usefully explored through examining the interrelationship of the deep structures underlying ideology and the type and sequence of rhetorical claims underpinning actors’ framing strategies. Our theoretical developments also allow us to better understand competing discourses influencing the diffusion process. These discourses reflect the ideologies and shape the framing strategies of actors in the broader field context. We illuminate our theoretical approach by drawing on the history of the diffusion of free and open source software.

Low-carbon off-grid electrification for rural areas in the United Kingdom: Lessons from the developing world

Low-carbon off-grid electrification for rural areas is becoming increasingly popular in the United Kingdom. However, many developing countries have been electrifying their rural areas in this way for decades. Case study fieldwork in Nepal and findings from United Kingdom based research will be used to examine how developed nations can learn from the experience of developing countries with regard to the institutional environment and delivery approach adopted in renewable energy off-grid rural electrification. A clearer institutional framework and more direct external assistance during project development are advised. External coordinators should also engage the community in a mobilization process a priori to help alleviate internal conflicts of interest that could later impede a project. © 2011 Elsevier Ltd.

Low-carbon off-grid electrification for rural areas: Lessons from the developing world

Low-carbon off-grid electrification for rural areas is becoming increasingly popular in developed nations such as the United Kingdom. However, many developing countries have been electrifying their rural areas in this way for decades. Case study fieldwork in Nepal and findings from UK-based research will be used to examine how developed nations can learn from the experience of developing countries with regards the institutional environment and delivery approach adopted in renewable energy off-grid rural electrification. A clearer institutional framework and more direct external assistance during project development are advised. External coordinators should also engage the community in a mobilization process a priori to help alleviate internal conflicts of interest that could later impede a project. ©2010 IEEE.

Determinantal Clustering Processes - A Nonparametric Bayesian Approach to Kernel Based Semi-Supervised Clustering

Semi-supervised clustering is the task of clustering data points into clusters where only a fraction of the points are labelled. The true number of clusters in the data is often unknown and most models require this parameter as an input. Dirichlet process mixture models are appealing as they can infer the number of clusters from the data. However, these models do not deal with high dimensional data well and can encounter difficulties in inference. We present a novel nonparameteric Bayesian kernel based method to cluster data points without the need to prespecify the number of clusters or to model complicated densities from which data points are assumed to be generated from. The key insight is to use determinants of submatrices of a kernel matrix as a measure of how close together a set of points are. We explore some theoretical properties of the model and derive a natural Gibbs based algorithm with MCMC hyperparameter learning. The model is implemented on a variety of synthetic and real world data sets.

Increasing allowable deformation criteria through application of level II LTSM approach

In the central part of the Delft railway tunnel project, an underground railway station is being built at very close distance to the existing station building, which is still in operation. Although elaborate sensitivity analyses were made, some unforeseen deformations were encountered during the first phases of the execution process. Especially the installation of temporary sheet pile walls as well as the installation of a huge amount of grout anchor piles resulted in deformations exceeding the predicted final deformations as well as the boundary values defined by a level I limiting tensile strain method (LTSM) approach. In order to ensure the execution process, supplementary analyses were made to predict future deformations, and this for multiple cross sections. These deformations were implemented into a finite element model of the masonry of the building in order to define probable crack formation. This Level II LTSM approach made it possible to increase the initially foreseen deformation criteria and the continuation of the works. Design steps, design models and monitoring results will be explained within this paper.