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Transit crimes in the Internet age: How new online criminal opportunities affect the organization of offline transit crimes
No full textThere is a general consensus that the Internet has expanded possibilities for so-called transit crimes—i.e., traditional trafficking activities. However, the extent to which the Internet is exploited by offenders to carry out transit crimes and the way in which it has changed those offenders’ behaviors and the criminal processes remains under- investigated.
The aim of this thesis is to understand what kind of criminal opportunities the Internet offers for conducting transit crimes and how these opportunities affect the organization of transit crimes, as concerns both the carrying out of the criminal activity and the patterns of relations in and among criminal networks.
In order to achieve this goal, a model of script analysis—a way to highlight the sequence of actions that are carried out for a determinate criminal activity to occur— was developed in order to classify the criminal opportunities that the Internet supplies for selected transit crimes (wildlife trafficking, trafficking in counterfeit medicines, sex trafficking, and trafficking in recreational drugs), to identify cyber-hotspots, and to allow a richer and deeper understanding of the dynamics of Internet-mediated transit crimes. The data were collected by means of case study research and semi-structured interviews to law enforcement officers and acknowledged experts.
For each criminal activity considered, through the script framework it has been possible to identify different types of criminal opportunities provided by the Internet. The
empirical evidence presented demonstrates that the criminal markets considered have become—even if to a different extent—hybrid markets which combine the traditional social and economic opportunity structures with the new one provided by the Internet. Among other findings, this research indicates that not only has the Internet opened the way for new criminal actors, but it also has reconfigured relations among suppliers, intermediaries, and buyers. Furthermore, results were compared across transit crimes to illustrate whether and to what extent Internet usage impacts them differently. The differences seem to depend primarily on the social perception of the seriousness of the criminal activity, on the place it fills in the law enforcement agenda, and on the characteristics of the actors involved.
This study, albeit with limitations, provides an accurate description of the Internet as crime facilitator for transit crimes. It concludes by highlighting the possibilities of environmental criminology as a theoretical framework to investigate Internet-mediated transit crimes, offering some final observations on how relevant actors behave online, and suggesting new directions for research
Dislocations and Green's functions in prestressed solids
Get PDFThe present Ph.D. dissertation is divided into two Parts: Green's function and problems of the inclusions and dislocations are addressed in the first Part, while implementation of elastoplastic constitutive laws are treated in the second.
These subjects can be seen as different approaches to the investigation of the plastic behaviour of materials.
In the first Part, infinite-body two-dimensional Green's functions are derived for the incremental deformation of an incompressible, anisotropic, prestressed body.
These functions, given by Bigoni and Capuani, show the response of an infinite body to a concentrated force.
The effect of prestress on dislocation (and inclusion) fields in non-linear elastic solids is analyzed by extending previous solutions by Eshelby and Willis.
Employing a plane strain constitutive model (for incompressible incremental non-linear elasticity) to describe the behaviour a broad class of (anisotropic) materials, but with a special emphasis on ductile metals (J2-deformation theory of plasticity), it is shown that strongly localized strain patterns emerge, when a dislocation dipole is emitted by a source and the prestress level is high enough.
These strain patterns may explain cascade activation of dislocation clustering along slip band directions.
Several of the presented results remain valid within a three-dimensional context.
Novel infinite-body three-dimensional Green's functions are derived for the incremental deformation of an incompressible, anisotropic, prestressed body.
The case of a force dipole is developed within this framework.
Results are used to investigate the behaviour of a material deformed near the limit of ellipticity loss and to reveal features related to shear failure cones development in a three-dimensional solid medium.
Non-standard elastoplastic constitutive laws are treated in the second Part of the present Ph.D. dissertation, based on pressure-sensitive yield functions, such that proposed by Bigoni and Piccolroaz, which describes the inelastic deformation of ceramic powders and of a broad class of rock-like and granular materials.
This yield function is not defined outside the yield locus, so that 'gradient-based' integration algorithms of elastoplasticity cannot be directly employed.
Therefore, two ad hoc integration algorithms are proposed: an explicit scheme based on a forward Euler technique with a 'centre-of-mass' return correction and an implicit scheme based on a 'cutoff-substepping' return algorithm
Signoria ecclesiastica e comunità rurali nel medioevo (secoli XII-XIII). S. Giorgio in Braida di Verona e i villaggi del Fiumenovo. Ecclesiastic Lordship and Rural Communities in the Middle Ages (12-13th c.). St Giorgio in Braida of Verona and the villages of Fiumenovo.
No full textThe thesis analyses the relationships between the urban church of Verona and three of its subject villages (Cologna, Sabbion and Zimella), located in the eastern territory of Verona's district in the Communal Age. The introductive chapter is aimed at defining the object and the chronology of the research, and the 'status quaestionis' concerning rural lordship in the Italian historiography. The first section focuses mostly on the urban milieu, where the canons of St Giorgio lived and built their strategies and connections with the communal establishment. The second section analyses the environmental, settlement, social and institutional development of the three mentioned villages, contextualised in the dialectics between the city-state and the seigniorial powers in the district. The thesis includes two appendices consisting in the edition of 26 previously unpublished documents coming from the Vatican Archives and the State Archive of Verona
Fenomeni identitari e appartenenza religiosa: problemi storiografici e aspetti politici della cristianizzazione dei Goti
No full textLa tesi si propone di dimostrare la fallacia delle varie ricostruzioni relative alla cristianizzazione di massa dei Goti, che pongono l'accento di volta in volta sul ruolo di Ulfila o di Valente, e sul portato identitario del cristianesimo subordinazionista abbracciato dai barbari. In effetti, il fenomeno di conversione è ben più complesso e si svolge tra il III e il V secolo, intrecciandosi continuamente con le relazioni politiche e diplomatiche tra Romani e Goti. La vera e propria "conversione di massa" non può dirsi conclusa prima dello stanziamento dei Goti in Aquitania nel 418. Solo con il regno di Teoderico II, e ancor più all'epoca di Eurico e Alarico II, i re di Tolosa iniziano a proporre la propria fede religiosa come elemento identitario e come "strategy of distinction" rispetto ai Romani residenti in Gallia
Improving the security of the Android ecosystem
No full textDuring the last few years mobile phones have been being replaced by new devices called smartphones. A more ``intelligent'' version of a mobile phones, smartphones combine usual ``phoning'' facilities with the functionality and performance of personal computers. Moreover, they are equipped with various sensors, such as camera and GPS, and are open to third-party applications. Being almost all the time with their users, it is not surprising that smartphones have access to very sensitive private data. Unfortunately, these data are of particular interest not only to the device owners. Developers of third-party applications embed data collection functionality either to feed advertising frameworks or for their own purposes. Moreover, there are also adversaries aiming at gathering personal user information or performing malicious actions. In this situation the users have a strong motivation to safeguard their devices from being misused and want to protect their privacy.Among all operating systems for mobile platforms, Android developed by Google is the recognized leader. This operating system is installed on four out of five new devices. In this thesis we propose a set of improvements to enhance security of the Android ecosystem and ensure trustworthiness of the applications installed on the device. In particular, we focus on the application ecosystem security, and research the following key aspects: identification of suspicious applications; application code analysis for malicious functionality; distribution of verified applications to end-user devices; and enforcing security on the device itself. It was previously shown that adversaries often relied on app repackaging to burst the proliferation of malicious applications. As the first contribution, this dissertation proposes a fast approach to detect repackaged Android applications. If a repackaged application is detected, it is necessary to understand whether it is malicious or not. Today Android malware conceal their malicious nature using dynamic code update techniques, thus, static analyzers cannot detect this vicious behavior. The second contribution of this work is a static-dynamic analysis approach to discover and analyse apps in the presence of dynamic code updates routines. To increase the user's confidence in the installed apps, as the third contribution we propose the concept of trusted stores for Android. Our approach ensures that a user can install only the applications vetted and attested by trusted stores. Finally, the forth contribution is the design and implementation of a policy-based framework for enforcing software isolation of applications and data that may help to improve the security of end-user devices
Essays on the effects of human capital, innovation and technology on economic performance
No full textThis thesis is on human capital (HC) and innovation in Germany and comprises of three essays. The first essay provides a comparative analysis on the economic performance impacts of creative class and HC at regional level with the purpose of testing whether the contemporary occupation-based creative class or the conventional education-based HC can be used as a better driver of regional economy. In doing so, I disaggregate creative class into creative core (scientific experts), creative professionals (associate scientists), and art experts while HC is categorized into primary and secondary school graduates with and without vocational training, and university graduates. Further, I proxy the outcome variable regional economic performance by inflation adjusted economic growth, employment growth, and wage growth. All economic performance, HC, and creative class data are drawn from the Sample of Integrated Labor Market Biographies (SIAB 1975–2008) and from the Federal Statistical Office of Germany which cover the years 1998–2008 inclusive for 394 administrative regions (Nomenclature of Territorial Units for Statistics – NUTS3). Estimations, using system generalized method of moments (SGMM), reveal that human capital (share of university graduates) is superior to creative class (share of scientific and associate scientists) in generating economic growth, employment growth is better predicted by creative class, and that creative class and HC appear to have equivalent influence on wage growth. The estimation further indicates that art experts have a deterring effect on wage, employment, as well as on economic growth, hence, rejecting Florida’s (2002) thesis. The second essay analyzes the impacts of innovation input and innovation output on the performance of 3124 manufacturing and service firms based on rich longitudinal data that cover the years 2003–2010 inclusive. The data—which are drawn from Mannheim Innovation Panel (MIP)—share many of the characteristics of the Community Innovation Survey (CIP) data but also have at least two unique features. First, unlike CIS, MIP is an annual panel survey which provides more opportunity to analyze persistence of innovation activities and causal effects between innovation input and innovation output, and between innovation and firm performance. Second, and more importantly, MIP survey goes beyond the standard CIS questionnaires and includes data on firm profitability, firm’s market competition, innovation input, and innovation output. Third, annual survey data further minimizes the risk of data jumps or gaps over years, therefore, yield more chance to use a dynamic panel estimator that can effectively trace innovation persistence. Such unique features of the survey panel data— in conjunction with the method developed by Oslo manual of innovation—allow to measure innovation input by R&D intensity, investment innovation intensity, and total innovation intensity; proxy innovation output through product innovation to firm, product innovation to market, and process innovation; and explain firm performance by employment, sales and labor productivity. The analysis uncovers that innovation input and innovation output do affect growth of employment, sales, and labor productivity differently within and between manufacturing and service firms. More importantly, innovation input compared to innovation output appears to better explain innovation and, in turn, drive firm performance. The third essay, an extension of the second essay, analyzes the influences of technological innovation (measured by R&D intensity, patents, and share of researchers) on economic performance [growth of per capita income (PCI), employment, and wage] in 96 planning regions on the basis of five years (every two years) panel data over the years 2001-2009. The five year average cross-section and panel data estimations show that most of the employed innovation indicators have not only a statistically robust but also an economically strong impact on the economic performance of the planning regions. More specifically, the panel estimation provides information that the lagged dependent variables of investment in R&D, patent claim, and the share of high-tech and knowledge intensive employees impact PCI, employment, and wage growth immensely. However, the elasticity of the effects differ. Non high-tech and knowledge intensive services employees—who are identified in the dataset as non-researchers—have also positive and substantial impact on regional economy. This may suggest that non-researchers can innovate and, in turn, play a crucial role in harnessing regional economy
Adaptation in Non-Parametric State Estimation with Application to People Tracking
No full textThe employment of visual sensor networks in surveillance systems has brought in as many challenges as disadvantages. While the integration of multiple cameras into a network has the potential advantage of fusing complementary observations from sensors and enlarging visual coverage, it also increases the complexity of tracking tasks and poses challenges to system scalability. The research work in this thesis addresses the problem of building an efficient and scalable multi-camera tracking system that (i) adapts, in real time, to the dynamics of the monitored scenario and (ii) attempts to maximize usage and sharing of available sensing and processing resources. To perform reliable tracking, a preliminary step is fast and accurate people detection, for which we propose a locus-based probabilistic occupancy map (LPOM). The LPOM computes the probability of targets being in the map by using only motion information plus calibration data. To make the tracking system more scalable, we present a decentralized multi-camera multi-people tracking framework with a three-layer architecture, in which we formulate the overall task (i.e. tracking all people using all available cameras) as a vision based state estimation problem and aim to maximize utility and sharing of available sensing and processing resources. By exploiting the geometric relations between sensing geometry and people's positions, our method is able to dynamically and adaptively partition the overall task into a number of nearly independent subtasks with the aid of information theory, each of which tracks a subset of people with a subset of cameras (or agencies). The method hereby reduces task complexity dramatically and helps to boost parallelization and maximize the system's real time throughput and reliability while accounting for intrinsic uncertainty induced, e.g., by visual clutter, occlusion, and illumination changes. Moreover, we propose a preliminary information theoretical framework, in which we apply task-driven polling strategies that control the sensing process to minimize the number of observations to be processed while maximizing their expected impact on estimation process, and use parameter adaptation techniques to reallocate computational resources dynamically and opportunistically according to task complexity and measured evidence. For each proposed approach we carry out a number of experiments and demonstrate its efficiency and advantages
Task-Related Reinforcement Signals and Visual Plasticity
No full textIn the last decade, a consistent body of research has shown that the correct identification of task-relevant items can cause a transitory increase in human perceptual sensitivity. In the present work I report evidence of short- and long-term changes in perceptual processing triggered by the recognition of visual targets. This collection of studies suggests that targets recognition may trigger internal signals of reinforcement which, in turn, would foster cortical plasticity. Interestingly, such endogenous signals seem to be modulated by the presence of external reward and by intrinsic aspects of task performance
Essays on the Ethiopian Agriculture
No full textImproving agricultural productivity, agricultural commercialization and improving the livelihoods of the population are the main challenges in the Sub-Saharan Africa region where the majority of the population are poor and live in rural areas. Several factors including lack of improved farming practices, poor infrastructure, low level of market integration to the world market and within countries, climate change, and inadequate policy support restrained the performance of the agricultural sector in the region. This thesis consists of four chapters, three empirical and one theoretical chapter. Each of the empirical chapters deals with selected topics pertinent to the agriculture sector in Ethiopia. The theoretical chapter reviews the agricultural policies adopted by the existing government and implemented over the past two decades. After the introductory chapter, the second chapter analyzes the impacts of climate change on crop yields and yield vari-ability in Ethiopia. The impacts of climate change appear to be different across crops and regions. However, the future crop yield levels largely depend on future technological development in farming practices. The third chapter aims to understand the extent of price transmissions from the world markets to domestic grain markets, and the extent of market integration in domestic grain markets. The fourth chapter investigates and compares the volatilities of oilseeds prices in the world and domestic markets. The data used in the second, third and fourth chapters are obtained from various secondary sources. The fifth chapter reviews major agricultural policies implemented over the last two decades and identifies policies that either enhanced the growth of the agricultural sector or holding back its performance. The sixth chapter underlines the main conclusions and indicates future research areas
Indigenous Peoples and Self-Determined Development: the Case of Community Enterprises in Chiapas
No full textMost exogenous developmental models have not provided satisfactory results in indigenous settings. The resulting development policies have contributed to the expropriation of indigenous territories and to the indiscriminate exploitation of natural resources, that have led to a generalized worsening of indigenous peoples’ living conditions. The expression “development aggression” has been coined to describe the violation of indigenous individual and collective rights during development processes that have been imposed top-down rather than shared and implemented with the communities involved.
Against this background, several studies have pinpointed the role of indigenous entrepreneurship in sustaining endogenous development processes. Due to the low number of empirical studies supporting this proposition, this research aims at contributing to the debate, claiming that community enterprises are an effective vehicle for an indigenous self- determined process of development. More specifically, these grassroots entrepreneurial initiatives appear able to sustain an indigenous conception of well-being that has recently entered the Latin American debate on development. This conception, named buen vivir, emphasizes the importance of indigenous culture, the natural environment, and collective well-being.
Based on a multidisciplinary approach that draws on entrepreneur- ship, economic sociology, anthropology, and development studies, the re- search combines theoretical and empirical approaches. An ethnographic study has been carried out in the first half of 2012 and has investigated sixteen self-managed community enterprises that have been founded by indigenous Mayan communities in the Mexican state of Chiapas. The fieldwork has been based on in-depth semi-structured interviews, as well as direct observation and analysis of secondary sources. The focus is on identifying the enabling factors that have supported the emergence of these enterprises and the impact they have had on improving indigenous peoples’ well-being.
The main findings pinpoint the existence of some enabling factors for the emergence of community enterprises in the indigenous context, that have to be found in the indigenous cultural resources on which they are based, in the linkages they hold with social movements, and in the situation of social and economic stress of the context in which they are embedded. The research has also highlighted that in the context ana- lyzed community enterprises maintain some specific characteristics: they have a civic origin, thus they are not externally driven; they pursue a plurality of goals, which are not only social and economic, but also political, cultural and environmental; they have a participatory governance, based on equality among members and on democratic principles; and an entrepreneurial dimension that is explicitly aimed at pursuing social objectives through the continuous production of goods or services. These four characteristics explain the contribution that community enterprises can offer in supporting alternative approaches to development, where local communities are actors of their own development processes