Spatio-Temporal Reasoning About Agent Behavior

There are many applications where we wish to reason about spatio-temporal aspects of an agent's behavior. This dissertation examines several facets of this type of reasoning. First, given a model of past agent behavior, we wish to reason about the probability that an agent takes a given action at a certain time. Previous work combining temporal and probabilistic reasoning has made either independence or Markov assumptions. This work introduces Annotated Probabilistic Temporal (APT) logic which makes neither assumption. Statements in APT logic consist of rules of the form "Formula G becomes true with a probability [L,U] within T time units after formula F becomes true'' and can be written by experts or extracted automatically. We explore the problem of entailment - finding the probability that an agent performs a given action at a certain time based on such a model. We study this problem's complexity and develop a sound, but incomplete fixpoint operator as a heuristic - implementing it and testing it on automatically generated models from several datasets. Second, agent behavior often results in "observations'' at geospatial locations that imply the existence of other, unobserved, locations we wish to find ("partners"). In this dissertation, we formalize this notion with "geospatial abduction problems" (GAPs). GAPs try to infer a set of partner locations for a set of observations and a model representing the relationship between observations and partners for a given agent. This dissertation presents exact and approximate algorithms for solving GAPs as well as an implemented software package for addressing these problems called SCARE (the Spatio-Cultural Abductive Reasoning Engine). We tested SCARE on counter-insurgency data from Iraq and obtained good results. We then provide an adversarial extension to GAPs as follows: given a fixed set of observations, if an adversary has probabilistic knowledge of how an agent were to find a corresponding set of partners, he would place the partners in locations that minimize the expected number of partners found by the agent. We examine this problem, along with its complement by studying their computational complexity, developing algorithms, and implementing approximation schemes. We also introduce a class of problems called geospatial optimization problems (GOPs). Here the agent has a set of actions that modify attributes of a geospatial region and he wishes to select a limited number of such actions (with respect to some budget and other constraints) in a manner that maximizes a benefit function. We study the complexity of this problem and develop exact methods. We then develop an approximation algorithm with a guarantee. For some real-world applications, such as epidemiology, there is an underlying diffusion process that also affects geospatial proprieties. We address this with social network optimization problems (SNOPs) where given a weighted, labeled, directed graph we seek to find a set of vertices, that if given some initial property, optimize an aggregate study with respect to such diffusion. We develop and implement a heuristic that obtains a guarantee for a large class of such problems

Data Driven Inference in Populations of Agents

abstract: In the artificial intelligence literature, three forms of reasoning are commonly employed to understand agent behavior: inductive, deductive, and abductive.  More recently, data-driven approaches leveraging ideas such as machine learning, data mining, and social network analysis have gained popularity. While data-driven variants of the aforementioned forms of reasoning have been applied separately, there is little work on how data-driven approaches across all three forms relate and lend themselves to practical applications. Given an agent behavior and the percept sequence, how one can identify a specific outcome such as the likeliest explanation? To address real-world problems, it is vital to understand the different types of reasonings which can lead to better data-driven inference.   This dissertation has laid the groundwork for studying these relationships and applying them to three real-world problems. In criminal modeling, inductive and deductive reasonings are applied to early prediction of violent criminal gang members. To address this problem the features derived from the co-arrestee social network as well as geographical and temporal features are leveraged. Then, a data-driven variant of geospatial abductive inference is studied in missing person problem to locate the missing person. Finally, induction and abduction reasonings are studied for identifying pathogenic accounts of a cascade in social networks.Dissertation/ThesisDoctoral Dissertation Computer Science 201

Preserving Privacy in Mobile Environments

Technology is improving day-by-day and so is the usage of mobile devices. Every activity that would involve manual and paper transactions can now be completed in seconds using your ngertips. On one hand, life has become fairly convenient with the help of mobile devices, whereas on the other hand privacy of the data and the transactions occurring in the process have been under continuous threat. Mobile devices connect to a number of service providers for various reasons. These could include downloading data, online purchasing or could be just used to browse information which may be irrelevant at a later point. Access to critical and sensitive information may be available at a number of places. In case of a mobile device, the information may be available with the service provider. Service Provider could be in the form of any web portal. In all such scenarios, passing the information or data from the service provider into the mobile device is a major challenge, as the data/information cannot be sent in plain text format. The con dentiality and integrity of the data needs to be protected and hence, the service provider must convert the data into an encrypted format before passing it onto the mobile device, to prevent risks from sniffing and unauthorized disclosure of data. Preserving the location of the individual user of any mobile device has also been the concern for a number of researchers. Mobile devices have become an important tool in modern communication. Mobile and other handheld devices such as ipads and tablets have over taken laptops and desktops and hence there has been an increasing research interest in this area in recent years. This includes improving the quality of communication and the overall end-to-end data security in day-to-day transactions. Mobile devices continuously connect to di erent service providers for day-to-day needs such as online purchases, online banking and endless sur ng for information. In addition to this devices could be connecting to the service providers to receive or send sensitive information. At the Service Provider end, the data would be stored with the provider and Service Provider would only hand over the data if it con rms that the person requested it is authorized to receive the information. The exchange of data from one end of the network to the other is a major challenge due to malicious intruder mishandling of the data. Hence the con dentiality and integrity of the data needs to be protected either by transforming the sensitive information into a non-readable format or by converting into a cipher text. Privacy has been an open problem for research as more and more information is getting leaked on a day-to-day basis. Through this thesis, I have tried to address a number of areas within the privacy realm where information and data access and sharing is a key concern along side the key aspect of location privacy. I have also tried to address the problems in the space of access control wherein I have proposed policy based languages and extensions for ensuring appropriate access control methodologies. The main goal and focus in this work has been to enforce the importance of location privacy in mobile environments and to propose solutions that resolve the problems of where and when to enforce location security. Another key goal of this work has been to create new access control and trust based solutions to ensure the right level of access to the right receiver of information. Through my research, I have explored the various privacy related attacks and suggested appropriate countermeasures for the same. In addition to proposing and showcasing solutions using policy languages for access control, I have also introduced geospatial access control solutions to ensure that the right user is accessing or requesting for the right information from the right location. This helps the appropriate and the right use of the information by the right resource. Through my thesis I have also given equal importance to the trust aspects of sharing information. I have created new trust assessment models to show how fused information can be handled and how can trust be imposed on the information provider and the information itself. The main contribution of this thesis is to address the problems around protecting the data and individual's privacy and to propose solutions to mitigate these issues using new and novel techniques. They can be detailed as the following: In privacy, there is always a privacy versus utility tradeo and in order to make use of utility, trust in the location is essential. Through this research I have developed i) novel attestation models and access control methodologies including Privacy Preferences Platform (P3P) extensions, ii) Extensible Access Control Markup Language (XACML) extensions and iii) Geospatial access control through GeoXACML. iv)I have created new methodologies to enforce location privacy and shown where best to enforce privacy. v)I have also shown that global attestation is very crucial for privacy and needs accurate methods in place to attest user's location information for access. vi) Fusing of location information is very crucial as there could be a number of similar or con icting information produced about a common source and it is very important to assess and evaluate the trust level in the information. I have proposed, developed and implemented a new trust assessment framework. This framework looks at the incoming information and passes it on to the rule engine in the framework to make some inferences and then the trust assessment module computes the trust score based on forward chaining or background chaining scheme. The framework is used to evaluate the trust on the fused information in a streaming setup. vii) I have created new solutions to look at the similarity pro les and create identity enforcement through pro ling. I have shown methods of anonymisation for location privacy and identity privacy

Civil resistance and digital media in Uganda : hybrid spaces of resistance and expression

This research explores the ongoing political resistance in Uganda under the guise of the National Unity Platform (NUP) and its leader Robert Kyagulanyi Ssentamu, popularly known as Bobi Wine. The NUP, in its efforts to challenge the 37-year long rule of President Yoweri Museveni’s National Resistance Movement (NRM), has mobilized millions of young Ugandans through the adaptive use of various social media platforms. Evolving from a social movement into a formal political organization, the NUP’s resistance strategy has shifted into continued digital engagement and physical outreach into Uganda’s hinterlands. Taking a mixed-methods approach, this work seeks to present a trans-scalar view of the intersections between digital and physical spaces of political expression and resistance inside (and outside) Uganda today. The use of GIS to interrogate the relationship between telecommunications infrastructure and political unrest at a national scale presents an introductory context to the research. Content analysis of newspaper archives on the formalization of the People Power Movement into the NUP and forty surveys on the use of digital media and political action gradually “zoom in” the scale to focus on the emergence of the NUP and the environment which it finds itself. Proceeding to qualitatively focused methods, interviews with several members of the NUP (to include several of Wine’s chief lieutenants) highlights key themes of a digitally mediated resistance movement struggling to ground itself in rural territories. Lastly, a novel attempt at visualizing digital spaces in relation to a resistance movement is operationalized through participatory mapping. This research explores the unique ways in which Uganda’s political history and human geography affects the ongoing struggle for democratic reforms. Thematically, this work also grounds the NUP’s struggle in the global geopolitical competition between authoritarianism and pro-democracy movements, at times aligned or against neoliberal democratic states.Geography and the Environmen

With renewables for energy security

Taking into account the possible future exhaustion of fossil energy sources, the actual and near danger of climate change, the drastic increase of the greenhouse gases in the last 200 years, as well as the growing need for sustainable development, consumption and liveable environment, the increasing necessity of renewable energy sources becomes clear. Utilization of these energy sources have to acquire a bigger role in the field of energy supply, in order to enhance the energy security of Hungary, to decline the energy import dependence, to reduce the negative environmental impacts, and to recover the economy. The world’s hunger for energy is growing exponentially; this is why it is crucial to establish feasibility scenarios in the next decades, which are able to meet these expectations, and to increase the safety of the energy supply

With renewables for energy security

Taking into account the possible future exhaustion of fossil energy sources, the actual and near danger of climate change, the drastic increase of the greenhouse gases in the last 200 years, as well as the growing need for sustainable development, consumption and liveable environment, the increasing necessity of renewable energy sources becomes clear. Utilization of these energy sources have to acquire a bigger role in the field of energy supply, in order to enhance the energy security of Hungary, to decline the energy import dependence, to reduce the negative environmental impacts, and to recover the economy. The world’s hunger for energy is growing exponentially; this is why it is crucial to establish feasibility scenarios in the next decades, which are able to meet these expectations, and to increase the safety of the energy supply

Technological Leap, Statutory Gap, and Constitutional Abyss: Remote Biometric Identification Comes of Age

Federal interest in using facial recognition technology (“FRT”) to collect, analyze, and use biometric information is rapidly growing. Despite the swift movement of agencies and contractors into this realm, however, Congress has been virtually silent on the current and potential uses of FRT. No laws directly address facial recognition—much less the pairing of facial recognition with video surveillance—in criminal law. Limits placed on the collection of personally identifiable information, moreover, do not apply. The absence of a statutory framework is a cause for concern. FRT represents the first of a series of next generation biometrics, such as hand geometry, iris, vascular patterns, hormones, and gait, which, when paired with surveillance of public space, give rise to novel questions of law and policy. These technologies constitute what can be termed Remote Biometric Identification (“RBI”). That is, they give the government the ability to ascertain the identity (1) of multiple people, (2) at a distance, (3) in public space, (4) absent notice and consent, and (5) in a continuous and on-going manner. RBI fundamentally differs from what can be understood as Immediate Biometric Identification (“IBI”)--i.e., the use of biometrics to determine identity at the point of arrest, following conviction, or in conjunction with access to secure facilities. IBI, in contrast, tends to be focused (1) on a single individual, (2) close-up, (3) in relation either to custodial detention or in the context of a specific physical area related to government activity, (4) in a manner often involving notice and often consent, and (5) is a one-time or limited occurrence. The types of legal and policy questions raised by RBI significantly differ from those accompanying IBI. In the absence of a statutory framework, we are driven to Constitutional considerations, where the Court’s jurisprudence proves inadequate as a way of addressing the concerns that present in the realm of RBI. The Fourth Amendment’s guarantee to protection against unreasonable search and seizure and the probable cause requirement for the issuance of warrants; the Fifth Amendment’s right against self-incrimination; the First Amendment’s protection of speech and assembly; and the Fifth and Fourteenth Amendments’ due process protections fail to account for the way in which such measures fundamentally challenge the current norms. The article calls for Congressional action and a judicial framing commensurate with the threat posed by these new and emerging technologies

Affective Justice

Since its inception in 2001, the International Criminal Court (ICC) has been met with resistance by various African states and their leaders, who see the court as a new iteration of colonial violence and control. In Affective Justice Kamari Maxine Clarke explores the African Union's pushback against the ICC in order to theorize affect's role in shaping forms of justice in the contemporary period. Drawing on fieldwork in The Hague, the African Union in Addis Ababa, sites of postelection violence in Kenya, and Boko Haram's circuits in Northern Nigeria, Clarke formulates the concept of affective justice—an emotional response to competing interpretations of justice—to trace how affect becomes manifest in judicial practices. By detailing the effects of the ICC’s all-African indictments, she outlines how affective responses to these call into question the "objectivity" of the ICC’s mission to protect those victimized by violence and prosecute perpetrators of those crimes. In analyzing the effects of such cases, Clarke provides a fuller theorization of how people articulate what justice is and the mechanisms through which they do so