Search results for "Operations"
showing 10 items of 1692 documents
A Lagrangian Decomposition Approach to Solve Large Scale Multi-Sector Energy System Optimization Problems
2020
We consider the capacity and operations planning of a European energy supply system with a high share of renewable energy. Our model includes the energy sectors electricity, heat, and transportation and it considers numerous types of consumers and power generation, storage, and transformation technologies, which participate in these energy sectors. Given time series for the regional demands in each sector and the potential renewable production, the goal is to simultaneously optimize the strategic dimensioning and the hourly operation of all components in the system such that the overall costs are minimized.
ACCOUNTING AS A 21ST CENTURY BUSINESS VALUE DRIVER
2017
Companies have focused for decades on maximizing the value creation process of direct productive business activities. The information revolution has left its mark and has started an irreversible transformation of classical business processes and activities. In the new 21st century information and data driven society, commodity is value and knowledge, making Porters value chain concept an important key factor for successful and innovative businesses. Business value creation was during the industrial revolution a topic strictly liked to direct productive activities. The increased and transformed business environment required innovative and sustainable competitive advantages for business organ…
Viral marketing through e-mail: the link company-consumer
2013
Purpose – The purpose of this paper is to identify the antecedents that may determine the opening of e-mails from companies that endeavour to promote their products, and what may motivate individuals to forward such messages to others. Design/methodology/approach – The paper presents exploratory research to approach the nature of the viral process and descriptive research for testing the proposed hypotheses. Findings – The opening of an e-mail is determined by the value that an individual may perceive that the message might contain. Forwarding of the message is determined by its opening, and by the individual's perception about the value of the message it may provide to others, besides the…
Insights from a Simulation Model of Disaster Response: Generalization and Action Points
2016
In a prior paper we presented a system dynamics model that simulates responder behavior in a Norwegian landslide. The model shows how a set of vicious feedback loops caused by following standard organizational procedures that do not fit the disaster situation initially increases errors in response. Eventually learning and sensemaking in an improvisation/experimentation process leads to new emergent dynamics whereby the loops act virtuously. In this paper we aim to generalize this initial study by explaining in more detail how the model can describe large scale disaster responses of different types and how it relates to the wider disaster response literature. We discuss what types of levers,…
Ant colony optimisation for planning safe escape routes
2013
Published version of a chapter from the volume: Recent Trends in Applied Artificial Intelligence. Also available on SpringerLink: http://dx.doi.org/10.1007/978-3-642-38577-3_6 An emergency requiring evacuation is a chaotic event filled with uncertainties both for the people affected and rescuers. The evacuees are often left to themselves for navigation to the escape area. The chaotic situation increases when a predefined escape route is blocked by a hazard, and there is a need to re-think which escape route is safest. This paper addresses automatically finding the safest escape route in emergency situations in large buildings or ships with imperfect knowledge of the hazards. The proposed so…
The exploratory factor analysis of items: guided analysis based on empirical data and software
2017
El objetivo del presente trabajo es ilustrar cómo la aplicación adecuada o inadecuada del análisis factorial exploratorio (AFE) puede llevar a conclusiones muy diferentes. Para ello se evalúa el grado en que cuatro paquetes estadísticos diferentes que permiten realizar AFE de ítems, en concreto SPSS, FACTOR, PRELIS y MPlus, permiten o limitan la aplica- ción de los estándares actualmente recomendados en materia de análisis factorial. Asimismo se analizan y comparan los resultados que ofrecen di- chos programas cuando se factorizan datos empíricos de escalas que ajus- tan, según el caso, de manera inadecuada, ambigua u óptima a los supuestos del modelo AFE lineal clásico, a través de las dis…
A Bayesian network model for evacuation time analysis during a ship fire
2013
We present an evacuation model for ships while a fire happens onboard. The model is designed by utilizing Bayesian networks (BN) and then simulated in GeNIe software. In our proposed model, the most important factors that have significant influence on a rescue process and evacuation time are identified and analyzed. By applying the probability distribution of the considered factors collected from the literature including IMO, real empirical data and practical experiences, the trend of the rescue process and evacuation time can be evaluated and predicted using the proposed model. The results of this paper help understanding about possible consequences of influential factors on the security o…
Deviations in pedestrian itineraries in urban areas: a method to assess the role of environmental factors
2010
Walking has long been neglected in urban-mobility research, but it is now making its way into numerous studies using various approaches. Empirical data are often processed in well-known models of flow allocation to study the behaviour of pedestrians and to identify their preferences. However, these models assume that route choices are predetermined at the start of each trip and do not admit any possible intervening decision along these trips. We propose to overcome this limitation through a new method for the analysis of pedestrian behaviour. This method, which we call ‘deviation analysis’ consists of (1) identifying the intersections from which a pedestrian has chosen a route longer than …
Quality management in the public sector accounting department - (un)avoidable quality costs and unlikely financial impacts
2017
This paper investigates the nature of quality costs and the likelihood of their having financial impacts in the public sector. An illustrative quality development case project in an accounting department of a Finnish city administration is presented. The empirical data includes answers to a qualitative project question sheet, workshop material and participative observation. Quality problems are classified according to their quality cost category and the extent to which they are avoidable. Some of the quality costs proved unavoidable and some are likely to lack financial impact, exhibiting sticky cost behaviour. The study indicates that certain prevention and appraisal costs in the public se…
Business strategy in new high‐tech ventures: an empirical analysis
1999
The aim of this study is to determine the existence of specific and unique features characterising markets, activities and customers in at least two of the most representative high technology sectors nowadays, the microelectronics/software industry and the biotechnology/biomedical industry. Cross‐Tabs statistical method has been used to analyze the data collected from the sample made up by 18 high‐tech American firms. One of the major findings of this study is that the business strategy will hold better prospects in those high‐tech firms benefiting from a higher technological excellence, having spent longer time in developing and launching their products, being able to keep longer the novel…