A Neural Model of Visually Guided Steering, Obstacle Avoidance, and Route Selection

A neural model is developed to explain how humans can approach a goal object on foot while steering around obstacles to avoid collisions in a cluttered environment. The model uses optic flow from a 3D virtual reality environment to determine the position of objects based on motion discotinuities, and computes heading direction, or the direction of self-motion, from global optic flow. The cortical representation of heading interacts with the representations of a goal and obstacles such that the goal acts as an attractor of heading, while obstacles act as repellers. In addition the model maintains fixation on the goal object by generating smooth pursuit eye movements. Eye rotations can distort the optic flow field, complicating heading perception, and the model uses extraretinal signals to correct for this distortion and accurately represent heading. The model explains how motion processing mechanisms in cortical areas MT, MST, and VIP can be used to guide steering. The model quantitatively simulates human psychophysical data about visually-guided steering, obstacle avoidance, and route selection.Air Force Office of Scientific Research (F4960-01-1-0397); National Geospatial-Intelligence Agency (NMA201-01-1-2016); National Science Foundation (NSF SBE-0354378); Office of Naval Research (N00014-01-1-0624

Video browsing interfaces and applications: a review

We present a comprehensive review of the state of the art in video browsing and retrieval systems, with special emphasis on interfaces and applications. There has been a significant increase in activity (e.g., storage, retrieval, and sharing) employing video data in the past decade, both for personal and professional use. The ever-growing amount of video content available for human consumption and the inherent characteristics of video data—which, if presented in its raw format, is rather unwieldy and costly—have become driving forces for the development of more effective solutions to present video contents and allow rich user interaction. As a result, there are many contemporary research efforts toward developing better video browsing solutions, which we summarize. We review more than 40 different video browsing and retrieval interfaces and classify them into three groups: applications that use video-player-like interaction, video retrieval applications, and browsing solutions based on video surrogates. For each category, we present a summary of existing work, highlight the technical aspects of each solution, and compare them against each other

Housing Justice in Unequal Cities

Housing Justice in Unequal Cities is a global research network funded by the National Science Foundation (BCS 1758774) and housed at the Institute on Inequality and Democracy at UCLA Luskin. This open-access volume, co-edited by Ananya Roy and Hilary Malson, brings together movement-based and university-based scholars to build a shared field of inquiry focused on housing justice. Based on a convening that took place in Los Angeles in January 2019, at the LA Community Action Network and at the University of California, Los Angeles, the essays and interventions situate housing justice in the long struggle for freedom on stolen land. Embedded in the stark inequalities of Los Angeles, our work is necessarily global, connecting the city’s Skid Row to the indebted and evicted in Spain and Greece, to black women’s resistance in Brazil, to the rights asserted by squatters in India and South Africa. Learning from radical social movements, we argue that housing justice also requires a commitment to research justice. With this in mind, our effort to build a field of inquiry is also necessarily an endeavor to build epistemologies and methodologies that are accountable to communities that are on the frontlines of banishment and displacement

Long-term impacts of tropical storms and earthquakes on human population growth in Haiti and the Dominican Republic

Since the 18th century, Haiti and the Dominican Republic have experienced similar natural forces, including earthquakes and tropical storms. These countries are two of the most prone of all Latin American and Caribbean countries to natural hazards events, while Haiti seems to be more vulnerable to natural forces. This article discusses to what extent geohazards have shaped both nation's demographic developments. The data show that neither atmospheric nor seismic forces that directly hit the territory of Haiti have significantly affected the country's population growth rates and spatial population densities. Conversely, since the 1950s more people were exposed to atmospheric hazards, in particular, in regions which historically experienced higher storm frequencies

Protection of an intrusion detection engine with watermarking in ad hoc networks

Mobile ad hoc networks have received great attention in recent years, mainly due to the evolution of wireless networking and mobile computing hardware. Nevertheless, many inherent vulnerabilities exist in mobile ad hoc networks and their applications that affect the security of wireless transactions. As intrusion prevention mechanisms, such as encryption and authentication, are not sufficient we need a second line of defense, Intrusion Detection. In this pa-per we present an intrusion detection engine based on neural networks and a protection method based on watermarking techniques. In particular, we exploit information visualization and machine learning techniques in order to achieve intrusion detection and we authenticate the maps produced by the application of the intelligent techniques using a novel combined watermarking embedding method. The performance of the proposed model is evaluated under different traffic conditions, mobility patterns and visualization metrics

Black, Brown, and Powerful: Freedom Dreams in Unequal Cities

In April 2018, the Institute on Inequality and Democracy convened scholars, activists, policy advocates, community residents, and nonprofit workers to share and discuss research and action pertaining to processes of inequality in Los Angeles. We sought to shed light on the entangled structures of oppression, including urban displacement, housing precarity, racialized policing, criminal justice debt, forced labor, and the mass supervision and control of youth. Through keynote talks, group dialogue, and workshops, we analyzed how in Los Angeles, and elsewhere, black and brown communities face multiple forms of banishment and exploitation ranging from the criminalization of poverty to institutionalized theft.The question of racial banishment has been an important one for the Institute since its inauguration two years ago. This year though, amidst the troubled times of Trumpism, we wanted to shift our focus from banishment to freedom. In the reports that follow, you will find many examples of what Robin D.G. Kelley, a key presence at the Institute, has famously called “freedom dreams.” Located in, and thinking from South Central Los Angeles, the event’s participants provide insight into organizing frameworks and resistance strategies that challenge exclusion and refuse subordination. From tenant organizing to debtors’ unions, from underground scholars to educational reparations, visions of freedom abound. The Institute on Inequality and Democracy is convinced that university-based research can, and must, support such freedom dreams. Such partnership – between the public university and social justice movements – requires careful attention to the difficult task of decolonizing the university. This mandate is evident throughout this collection of reports. There is no easy alliance between academic power and banished communities; there is no obvious solidarity between urban plans and freedom dreams. This event was intended to be a step towards building such alliances, especially by reconstructing the curriculum and canon of knowledge