Search results for "performance indicator"
showing 10 items of 126 documents
Minimizing membrane bioreactor environmental footprint by multiple objective optimization.
2020
This paper presents a modelling study aimed at minimizing the environmental foot print of a membrane bioreactor (MBR) for wastewater treatment. Specifically, an integrated model for MBR was employed in view of the management optimization of an MBR biological nutrient removal (BNR) pilot plant in terms of operational costs and direct greenhouse gases emissions. The influence of the operational parameters (OPs) on performance indicators (PIs) was investigated by adopting the Extended-FAST sensitivity analysis method. Further, a multi-objective analysis was performed by applying the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). The results show-up that the sludge …
Mapping Economic Activity in the European Union: Do Ownership, Industry and Location Matter?
2020
The paper proposes a new method for analysing the structure and dynamics of economic activity undertaken by locally owned and foreign-owned companies within the European Union. We employ an unsupervised learning algorithm that generates a neural network depicted on Kohonen maps and offering a clustering of companies with a different ownership (local and foreign) from various industries and countries of the European Union during 2009–2016. The research methodology, based on a self-organizing map (SOM) algorithm, belongs to a class of neural networks trained to organize data so that unknown patterns may be discovered, thus leading to results that cannot be attained by more traditional cluster…
Institutional Logics in Police Performance Indicator Development : A Comparative Case Study of Spain and Finland
2015
Police performance is not easily measurable and the organization and circumstances of police work vary among European countries. Further, police work is surrounded by multiple pressures to make it both economical and effective. Consequently, there are multiple institutional logics in decision-making which may affect the selection and the use of police key performance indicators (KPIs). The KPI selection and use processes reflect the institutional logics, though KPI use may also sometimes influence the institutional logics of police work. In this study, we analyze the KPIs and institutional logics in police work in Finland and Spain. A comparative case research approach is used in order to h…
Green vs Traditional Roofs: Assessing their Actual Benefits through an Integrated Indicator Developed for Cool Roofs
2020
Green roofs have caught on in cities, mainly because contribute positively to thermal behaviour of buildings equipped with them. This paper investigates the applicability to these roofs of an integrated indicator, developed by Levinson and Akbari, to assess the contribution of cool roofs to buildings’ energy consumption. A building, assumed as the reference for the Italian medium size offices, was considered and its energy performance with and without the green roof was assessed. Different sites with different climatic conditions were considered for the simulations. First results indicate that such indicator does not seem to be completely transferable to green roofs.
Regression imputation for Space-Time datasets with missing values
2009
Data consisting in repeated observations on a series of fixed units are very common in different context like biological, environmental and social sciences, and different terminology is often used to indicate this kind of data: panel data, longitudinal data, time series-cross section data (TSCS), spatio-temporal data. Missing information are inevitable in longitudinal studies, and can produce biased estimates and loss of powers. The aim of this paper is to propose a new regression (single) imputation method that, considering the particular structure and characteristics of the data set, creates a “complete” data set that can be analyzed by any researcher on different occasions and using diff…
Modelling of Adequate Costs of Utilities Services
2016
The paper propose methodology for benchmark modelling of adequate costs of utilities services, which is based on the data analysis of the factual cases (key performance indicators of utilities as the predictors). The proposed methodology was tested by modelling of Latvian water utilities with three tools: (1) a classical version of the multi-layer perceptron with error back-propagation training algorithm was sharpened up with task-specific monotony tests, (2) the fitting of the generalized additive model using the programming language R ensured the opportunity to evaluate the statistical significance and confidence bands of predictors, (3) the sequential iterative nonlinear regression proce…
Key Economic Characteristics of Italian Trawl Fisheries and Management Challenges
2017
Two key measures of economic performance are calculated and analyzed for three important Italian trawl fisheries (Northern Thyrrenian Sea, South of Sicily, Northern Adriatic Sea): the Net Economic Returns (NER), which informs on the economic performance and is considered a proxy of resource rent in fisheries and the Return on Fixed Tangible Assets (ROFTA), which is used as an approximation of the Return on Investment (ROI) and is a key financial and performance indicator for a fisherman in order to take a decision to operate in a fishery. The trend of these indicators over the last decade highlights a poor economic performance that is associated with an overall poor condition of the state o…
A Pilot Study on Offensive Success in Soccer Based on Space and Ball Control – Key Performance Indicators and Key to Understand Game Dynamics
2017
Abstract The intention of Key Performance Indicators (KPI) is to map complex system-behaviour to single values for scaling, rating and ranking systems or system components. Very often, however, this mapping only reduces important information about tactical behaviour or playing dynamics without replacing it by useful ones. The presented approach tries to bridge the gap between complex dynamics and numerical indicators in the case of offensive effectiveness in soccer in two steps. First, a model is developed which visualises offensive actions in a process-oriented way by using information units to represent offensive performance – i.e. Key Performance Indicators. Second, this model is organis…
Structured methodology for selection of maintenance key performance indicators: Application to an oil refinery plant
2017
The novel contribution of the work is the proposal of a structured multi-step methodology that may support the Decision Maker (DM) in the measurement of maintenance performance by means of Maintenance Key Performance Indicators (MKPIs). To this aim, a multi-level hierarchical framework able to synthesize the most meaningful aspects affecting the maintenance results is designed. Then, MKPIs are selected from the literature, assigned to the hierarchical framework and ranked by an Analytic Hierarchy Process-based approach with incomplete comparison matrices. A mathematical model is finally formulated to select the optimal set of MKPIs. The methodology is implemented in an oil refinery plant an…
Assessing the efficiency of wastewater treatment plants in an uncertain context: a DEA with tolerances approach
2012
Abstract As the number of wastewater treatment plants (WWTPs) has increased, the economics associated with their management have become more relevant. The efficiency assessment is therefore a useful tool for cost reduction. For this purpose, Data Envelopment Analysis (DEA) is a highly suitable technique, since it is a holistic approach that aggregates performance indicators into a single index. However, one of the most common criticisms of DEA models is that information on uncertainty estimates is not provided. To overcome this limitation, we assess efficiency by using a DEA model with statistical tolerances for both inputs and outputs. This model is applied to a sample of Spanish WWTPs. Th…