Model for evaluating the efficiency of Russian water utilities

The objective of this study is to assess the efficiency of Russian water utilities based on a set of characteristic indicators. The novelty of the research is in the application of tools of the theory of economic “growth points” for analyzing water utility performance. The generalized development of a water utility is defined in terms of the efficiency of external and internal resources use. Conclusions on the development of water utilities in the six regional administrative centers of Siberia (Barnaul, Chita, Irkutsk, Novosibirsk, Omsk and Tomsk) in the 2013–2016 period were made.     

Productivity and efficiency in the water industry

Over the past twenty years there has been increasing interest in the productivity and efficiency of, and the optimal structures for, the water supply and wastewater industries. In part this interest has manifested itself in the increased use of numerous statistical techniques to determine the productivity and efficiency of the water sector in a variety of countries. The purpose of this paper is threefold. First it briefly reviews the various measures that have been used to gauge the levels of productivity and efficiency in the water sector, with particular reference to input and output data requirements of these measures. Second it summarises the key structural findings that have been determined from this research, particularly with respect to economies of scale and scope, public versus private ownership and the impact of regulation. Third, it considers potential areas for potential future research, such as the effect of environmental management activities (including water conservation) and regulation on productivity and efficiency, the role of wastewater as a potential source of potable or ‘fit-for-purpose’ water and the relationship between water supply and urban planning.     

Performance assessment of the Chilean water sector: A network data envelopment analysis approach

This study applies a two-stage network structure model to evaluate water service providers cost and operational performance embracing service quality variables. An empirical analysis of the Chilean water and wastewater industries over the 2010–2018 period is presented. Moreover, in the second stage of analysis, we analyzed the impact of a set of exogenous variables on the performance of water companies. Results revealed that the Chilean water companies had notable room to reduce costs and improve operational performance. Moreover, it was found that the public water provider performed better than fully private and concessionary water providers.     

Organizational enablers for governance and governmentality of projects: A literature review

This study identifies the organizational enablers for governance in the realm of projects. We first conceptualize organizational enablers as comprising of process facilitators and discursive abilities, each with its own factors and mechanisms. Then we apply this concept to the literature on project governance, governance of projects and governmentality. Outcomes indicate that governance is enabled through different forms of flexibility at different levels of governance, institutional setup and authority at the project level, flexible structures and mindsets of people at the organizational level, and through development of self-responsible, self-organizing people for governmentality in project settings. Questions for future research are indicated.     

Controllability analysis as a pre-selection method for sensor placement in water distribution systems

Detection of contamination events in water distribution systems is a crucial task for maintaining water security. Online monitoring is considered as the most cost-effective technology to protect against the impacts of contaminant intrusions. Optimization methods for sensor placement enable automated sensor layout design based on hydraulic and water quality simulation. However, this approach results in an excessive computational burden. In this paper we outline the application of controllability analysis as preprocessing method for sensor placement. Based on case studies we demonstrate that the method decreases the number of decision variables for subsequent optimization dramatically to app. 30 to 40 percent.     

Simplified thermal and hygric building models: A literature review

This paper provides a systematic literature review on simplified building models. Questions are answered like: What kind of modelling approaches are applied? What are their (dis)advantages? What are important modelling aspects? The review showed that simplified building models can be classified into neural network models (black box), linear parametric models (black box or grey box) and lumped capacitance models (white box). Research has mainly dealt with network topology, but more research is needed on the influence of input parameters. The review showed that particularly the modelling of the influence of sun irradiation and thermal capacitance is not performed consistently amongst researchers. Furthermore, a model with physical meaning, dealing with both temperature and relative humidity, is still lacking. Inverse modelling has been widely applied to determine models parameters. Different optimization algorithms have been used, but mainly the conventional Gaus–Newton and the newer genetic algorithms. However, the combination of algorithms to combine their strengths has not been researched. Despite all the attention for state of the art building performance simulation tools, simplified building models should not be forgotten since they have many useful applications. Further research is needed to develop a simplified hygric and thermal building model with physical meaning.     

Application of modified complementary reservoir approach in analysis of water distribution networks under pressure-deficient conditions

Hydraulic simulation models which simulate water distribution systems in different operating conditions are essential tools to evaluate network reliability. Simulation models found in most commercial software are not effectively capable of analyzing demand nodes under critical conditions such as fire-fighting demand or network pipe breakage. In the current study, a combination of hydraulic model and complementary reservoir solution (CRS) method is used for solving network's problems in critical conditions for both series-looped networks and a part of water network in Ilam city (Iran). Obtained results show that CRS provide more than actual need on the demand node for some reservoir total pressure heads. Thus, two modified versions of CRS method are proposed to deal with failures of CRS in such cases. Obtained results demonstrate improved efficiency in the combined model for analyzing networks in abnormal conditions.     

The effects of environmental factors on the patient outcomes in hospital environments:A review of literature

This study investigates the evidence supporting the impact of the built environment on the health outcomes for patients within the hospital setting. Improving the hospital environment may potentially impact the lives of millions of patients, patients' family, and staff. Prior research has suggested that the built environment can contribute to positive health outcomes. Reporting the most recent evidence may assist designers in making informed decisions. In this study, a literature review was conducted using the PICO framework within scientific databases and additional hand-searched documents. A total number of 15 articles were included. Effects of each environmental factor on patients' health outcomes were discussed in detail. Environmental factors that affect patient outcomes are (1) form, (2) unit layout, (3) floor material, (4) room features, (5) medical equipment visibility, (6) nature, (7) lighting, and (8) music. Although several studies have provided a high level of evidence, other studies have lacked a robust research design. Thus, evidence regarding several environmental factors is not conclusive. Additional studies using experimental/quasi-experimental research design have been suggested. In some studies, several environmental factors were introduced simultaneously which obscured the separate effects of each environmental factor.     

A state-of-the-art review of an optimal sensor placement for contaminant warning system in a water distribution network

ABSTRACT

Protection of water distribution networks (WDNs) is at the forefront because of the negative implications of the use of the contaminated water on the public health. In order to safeguard the water distribution networks from accidental and intentional attacks, a water quality sensor should be installed across the network. Remarkably, the budget constraints to procure and maintain sensors have limited the number of sensors deployed in networks. These constraints make the optimal sensor placement receive notable attention. Over time, researchers have devised various methodologies to tackle sensor placement in a water distribution network. Investigations have shown that each of the methodologies has a research gap which must be addressed. In this work, a state-of-the-art review of optimal sensor placement in a water distribution network is presented. The review results show technical challenges, possible solutions, and future research directions in this domain.     

A comprehensive bulk chlorine decay model for simulating residuals in water distribution systems

Chlorine decay models provide efficient ways to develop disinfection strategies for water distribution systems, provided they account separately for bulk and wall decay, and accurately describe decay with a single set of coefficients. The augmented two-reactant (2RA) model is shown to be the simplest model to accurately describe effects of rechlorination dose/timing on bulk chlorine decay, in combination with effects of initial concentration and temperature over long periods. The two-reactant (2R) and variable reaction-coefficient (VRC) models provided predictions of comparable accuracy under higher and successive rechlorination doses at constant temperature. However, the 2RA model provides a more general basis for strategy development, as the VRC model cannot describe the effect of temperature variation. The minimal data-set required for 2RA calibration was similar for all cases considered. The 2RA model is readily applied by incorporation into system modelling software such as the multi-species extension (MSX) to EPANET software.