Investigation of the Impacts of Large-Scale Wind Power Penetration on the Angle and Voltage Stability of Power Systems

The complexity of power systems has increased in recent years due to the operation of existing transmission lines closer to their limits, using flexible AC transmission system (FACTS) devices, and also due to the increased penetration of new types of generators that have more intermittent characteristics and lower inertial response, such as wind generators. This changing nature of a power system has considerable effect on its dynamic behaviors resulting in power swings, dynamic interactions between different power system devices, and less synchronized coupling. This paper presents some analyses of this changing nature of power systems and their dynamic behaviors to identify critical issues that limit the large-scale integration of wind generators and FACTS devices. In addition, this paper addresses some general concerns toward high compensations in different grid topologies. The studies in this paper are conducted on the New England and New York power system model under both small and large disturbances. From the analyses, it can be concluded that high compensation can reduce the security limits under certain operating conditions, and the modes related to operating slip and shaft stiffness are critical as they may limit the large-scale integration of wind generation.

Forecasting and visualization of wildfires in a 3D geographical information system

[EN]This paper describes a wildfi re forecasting application based on a 3D virtual environment and a fi re simulation engine. A novel open source framework is presented for the development of 3D graphics applications over large geographic areas, off ering high performance 3D visualization and powerful interaction tools for the Geographic Information Systems (GIS) community. The application includes a remote module that allows simultaneous connection of several users for monitoring a real wildfi re event.

Applicazione di strumenti e metodi per la gestione ambientale di un territorio vasto - Sviluppo di un sistema di gestione ambientale in un ente pubblico secondo lo schema europeo EMAS e analisi di un sistema energetico territoriale

Environmental Management includes many components, among which we can include Environmental Management Systems (EMS), Environmental Reporting and Analysis, Environmental Information Systems and Environmental Communication. In this work two applications are presented: the developement and implementation of an Environmental Management System in local administrations, according to the European scheme "EMAS", and the analysis of a territorial energy system through scenario building and environmental sustainability assessment. Both applications are linked by the same objective, which is the quest for more scientifically sound elements; in fact, both EMS and energy planning are oftec carachterized by localism and poor comparability. Emergy synthesis, proposed by ecologist H.T. Odum and described in his book "Environmental Accounting: Emergy and Environmental Decision Making" (1996) has been chosen and applied as an environmental evaluation tool, in order complete the analysis with an assessment of the "global value" of goods and processes. In particular, eMergy syntesis has been applied in order to improve the evaluation of the significance of environmental aspects in an EMS, and in order to evaluate the environmental performance of three scenarios of future evolution of the energy system. Regarding EMS, in this work an application of an EMS together with the CLEAR methodology for environmental accounting is discussed, in order to improve the identification of the environmental aspects; data regarding environmental aspects and significant ones for 4 local authorities are also presented, together with a preliminary proposal for the integration of the assessment of the significance of environmental aspects with eMergy synthesis. Regarding the analysis of an energy system, in this work the carachterization of the current situation is presented together with the overall energy balance and the evaluation of the emissions of greenhouse gases; moreover, three scenarios of future evolution are described and discussed. The scenarios have been realized with the support of the LEAP software ("Long Term Energy Alternatives Planning System" by SEI - "Stockholm Environment Institute"). Finally, the eMergy synthesis of the current situation and of the three scenarios is shown.

I doveri e le responsabilità contabili nella corporate governance delle società di capitali

La costruzione di un modello efficiente di corporate governance deve offrire una disciplina adeguata dei doveri contabili. Ciò nonostante, gli ordinamenti giuridici configurano i doveri di contabilità in modo incompleto, giacché l’inadempimento di questi non comporta una sanzione diretta per il soggetto inadempiente. Come informazione sulla situazione economica e finanziaria della società, esiste un interesse pubblico nella contabilità, e questa può servire come base di giudizio a soggetti interni ed esterni all’impresa, nell’adozione delle sue scelte. Disporre di un’informazione falsa o inesatta al riguardo può comportare un danno ingiustificato alla società stessa, ai soci o ai terzi, che potranno esercitare le azioni precise per il risarcimento del danno cagionato. Per evitare la produzione di questi danni, da una prospettiva preventiva, la corporate governance delle società di capitali può prevedere dei meccanismi di controllo che riducano il rischio di offrire un’informazione sbagliata. Questi controlli potranno essere esercitati da soggetti interni o esterni (revisori legali) alla struttura della società, ed avranno una configurazione diversa a seconda che le società adottino una struttura monistica o dualistica di governance. Questo ci colloca di fronte ad una eventuale situazione di concorrenza delle colpe, giacché i diversi soggetti che intervengono nel processo d’elaborazione dell’informazione contabile versano la sua attuazione sullo stesso documento: il bilancio. Risulta dunque cruciale determinare il contributo effettivo di ciascuno per analizzare il suo grado di responsabilità nella produzione del danno.

Metaheuristics for the Order Batching Problem in Manual Order Picking Systems

In manual order picking systems, order pickers walk or drive through a distribution warehouse in order to collect items which are requested by (internal or external) customers. In order to perform these operations efficiently, it is usually required that customer orders are combined into (more substantial) picking orders of limited size. The Order Batching Problem considered in this paper deals with the question of how a given set of customer orders should be combined such that the total length of all tours is minimized which are necessary to collect all items. The authors introduce two metaheuristic approaches for the solution of this problem: the first one is based on Iterated Local Search; the second on Ant Colony Optimization. In a series of extensive numerical experiments, the newly developed approaches are benchmarked against classic solution methods. It is demonstrated that the proposed methods are not only superior to existing methods but provide solutions which may allow distribution warehouses to be operated significantly more efficiently.

A Fast Platform for Interactive E-Learning Systems

Modern e-learning systems represent a special type of web information systems. By definition, information systems are special computerized systems used to perform data operations by multiple users simultaneously. Each active user consumes an amount of hardware resources. A shortage of hardware resources can be caused by growing number of simultaneous users. Such situation can result in overall malfunctioning or slowed-down system. In order to avoid this problem, the underlying hardware system gets usually continuously upgraded. These upgrades, typically accompanied with various software updates, usually result in a temporarily increased amount of available resources. This work deals with the problem in a different way by proposing an implementation of a web e-learning system with a modified software architecture reducing resource usage of the server part to the bare minimum. In order to implement a full-scale e-learning system that could be used as a substitute to a conventional web e-learning system, a Rich Internet Application framework was used as basis. The technology allowed implementation of advanced interactivity features and provided an easy transfer of a substantial part of the application logic from server to clients. In combination with a special server application, the server part of the new system is able to run with a reasonable performance on a hardware with very limited computing resources.

The German business and information technologies project

The Business and Information Technologies (BIT) project strives to reveal new insights into how modern IT impacts organizational structures and business practices using empirical methods. Due to its international scope, it allows for inter-country comparison of empirical results. Germany — represented by the European School of Management and Technologies (ESMT) and the Institute of Information Systems at Humboldt-Universität zu Berlin — joined the BIT project in 2006. This report presents the result of the first survey conducted in Germany during November–December 2006. The key results are as follows: • The most widely adopted technologies and systems in Germany are websites, wireless hardware and software, groupware/productivity tools, and enterprise resource planning (ERP) systems. The biggest potential for growth exists for collaboration and portal tools, content management systems, business process modelling, and business intelligence applications. A number of technological solutions have not yet been adopted by many organizations but also bear some potential, in particular identity management solutions, Radio Frequency Identification (RFID), biometrics, and third-party authentication and verification. • IT security remains on the top of the agenda for most enterprises: budget spending was increasing in the last 3 years. • The workplace and work requirements are changing. IT is used to monitor employees' performance in Germany, but less heavily compared to the United States (Karmarkar and Mangal, 2007).1 The demand for IT skills is increasing at all corporate levels. Executives are asking for more and better structured information and this, in turn, triggers the appearance of new decision-making tools and online technologies on the market. • The internal organization of companies in Germany is underway: organizations are becoming flatter, even though the trend is not as pronounced as in the United States (Karmarkar and Mangal, 2007), and the geographical scope of their operations is increasing. Modern IT plays an important role in enabling this development, e.g. telecommuting, teleconferencing, and other web-based collaboration formats are becoming increasingly popular in the corporate context. • The degree to which outsourcing is being pursued is quite limited with little change expected. IT services, payroll, and market research are the most widely outsourced business functions. This corresponds to the results from other countries. • Up to now, the adoption of e-business technologies has had a rather limited effect on marketing functions. Companies tend to extract synergies from traditional printed media and on-line advertising. • The adoption of e-business has not had a major impact on marketing capabilities and strategy yet. Traditional methods of customer segmentation are still dominating. The corporate identity of most organizations does not change significantly when going online. • Online sales channel are mainly viewed as a complement to the traditional distribution means. • Technology adoption has caused production and organizational costs to decrease. However, the costs of technology acquisition and maintenance as well as consultancy and internal communication costs have increased.

I like it because I (‘m) like You – measuring user attitudes towards information on Facebook

Limited in motivation and cognitive ability to process the increasing amount of information on their Newsfeed, users apply heuristic processing to form their attitudes. Rather than extensively analysing the content, they increasingly rely on heuristic cues – such as the amount of comments and likes as well as the level of relationship with the “poster” – to process the incoming information. In the paper we explore what impact these heuristic cues have on the affective and cognitive attitude of users towards the posts on their Newsfeed. We conduct a survey on based on a Facebook application that allows users to evaluate Newsfeed posts in real time. Applying two distinct panel-regression methods we report robust results that indicate that there is a certain relationship primacy effect when users are processing information: only if the level of relationship with the “poster” is low, the impact of comments and likes on the attitude is considered, whereby likes trigger positive, whereas comments – negative evaluations.

‘Stop spamming me!’: exploring information overload on Facebook

The problem of information overload on Facebook is exacerbating as users expand their networks. Growing quantity and increasingly poor quality of information on the Newsfeed may interfere with the hedonic experience of users resulting in frustration and dissatisfaction. In the long run, such developments threaten to undermine sustainability of the platform. To address these issues, our study adopts a grounded theory approach to explore the phenomenon of information overload on Facebook. We investigate main sources of information overload, identify strategies users adopt to deal with it as well as possible consequences. In-depth analysis of the phenomenon allows us to uncover individual peculiarities for identification of relevant information. Based on them we provide valuable recommendations for network providers.

The Evolution of Routines under flexible Information Technology

Many technological developments of the past two decades come with the promise of greater IT flexi-bility, i.e. greater capacity to adapt IT. These technologies are increasingly used to improve organiza-tional routines that are not affected by large, hard-to-change IT such as ERP. Yet, most findings on the interaction of routines and IT stem from contexts where IT is hard to change. Our research ex-plores how routines and IT co-evolve when IT is flexible. We review the literatures on routines to sug-gest that IT may act as a boundary object that mediates the learning process unfolding between the ostensive and the performative aspect of the routine. Although prior work has concluded from such conceptualizations that IT stabilizes routines, we qualify that flexible IT can also stimulate change because it enables learning in short feedback cycles. We suggest that, however, such change might not always materialize because it is contingent on governance choices and technical knowledge. We de-scribe the case-study method to explore how routines and flexible IT co-evolve and how governance and technical knowledge influence this process. We expect to contribute towards stronger theory of routines and to develop recommendations for the effective implementation of flexible IT in loosely coupled routines.

Dangers of ‘Facebook Login’ for Mobile Apps: Is There a Price Tag for Social Information?

Social networks offer horizontal integration for any mobile platform providing app users with a convenient single sign-on point. Nonetheless, there are growing privacy concerns regarding its use. These vulnerabilities trigger alarm among app developers who fight for their user base: While they are happy to act on users’ information collected via social networks, they are not always willing to sacrifice their adoption rate for this goal. So far, understanding of this trade-off has remained ambiguous. To fill this gap, we employ a discrete choice experiment to explore the role of Facebook Login and investigate the impact of accompanying requests for different information items / actions in the mobile app adoption process. We quantify users’ concerns regarding these items in monetary terms. Beyond hands-on insights for providers, our study contributes to the theoretical discourse on the value of privacy in the growing world of Social Media and mobile web.

Information Technology Outsourcing: Towards Sustainable Business Value

This book attempts to synthesize research that contributes to a better understanding of how to reach sustainable business value through information systems (IS) outsourcing. Important topics in this realm are how IS outsourcing can contribute to innovation, how it can be dynamically governed, how to cope with its increasing complexity through multi-vendor arrangements, how service quality standards can be met, how corporate social responsibility can be upheld, and how to cope with increasing demands of internationalization and new sourcing models, such as crowdsourcing and platform-based cooperation. These issues are viewed from either the client or vendor perspective, or both. The book should be of interest to all academics and students in the fields of Information Systems, Management, and Organization as well as corporate executives and professionals who seek a more profound analysis and understanding of the underlying factors and mechanisms of outsourcing.