A framework for automatic feature extraction from airborne light detection and ranging data

Recent advances in airborne Light Detection and Ranging (LIDAR) technology allow rapid and inexpensive measurements of topography over large areas. Airborne LIDAR systems usually return a 3-dimensional cloud of point measurements from reflective objects scanned by the laser beneath the flight path. This technology is becoming a primary method for extracting information of different kinds of geometrical objects, such as high-resolution digital terrain models (DTMs), buildings and trees, etc. In the past decade, LIDAR gets more and more interest from researchers in the field of remote sensing and GIS. Compared to the traditional data sources, such as aerial photography and satellite images, LIDAR measurements are not influenced by sun shadow and relief displacement. However, voluminous data pose a new challenge for automated extraction the geometrical information from LIDAR measurements because many raster image processing techniques cannot be directly applied to irregularly spaced LIDAR points. ^ In this dissertation, a framework is proposed to filter out information about different kinds of geometrical objects, such as terrain and buildings from LIDAR automatically. They are essential to numerous applications such as flood modeling, landslide prediction and hurricane animation. The framework consists of several intuitive algorithms. Firstly, a progressive morphological filter was developed to detect non-ground LIDAR measurements. By gradually increasing the window size and elevation difference threshold of the filter, the measurements of vehicles, vegetation, and buildings are removed, while ground data are preserved. Then, building measurements are identified from no-ground measurements using a region growing algorithm based on the plane-fitting technique. Raw footprints for segmented building measurements are derived by connecting boundary points and are further simplified and adjusted by several proposed operations to remove noise, which is caused by irregularly spaced LIDAR measurements. To reconstruct 3D building models, the raw 2D topology of each building is first extracted and then further adjusted. Since the adjusting operations for simple building models do not work well on 2D topology, 2D snake algorithm is proposed to adjust 2D topology. The 2D snake algorithm consists of newly defined energy functions for topology adjusting and a linear algorithm to find the minimal energy value of 2D snake problems. Data sets from urbanized areas including large institutional, commercial, and small residential buildings were employed to test the proposed framework. The results demonstrated that the proposed framework achieves a very good performance. ^

Autonomic and embedded wireless sensor protocols for critical infrastructures

The tragic events of September 11th ushered a new era of unprecedented challenges. Our nation has to be protected from the alarming threats of adversaries. These threats exploit the nation's critical infrastructures affecting all sectors of the economy. There is the need for pervasive monitoring and decentralized control of the nation's critical infrastructures. The communications needs of monitoring and control of critical infrastructures was traditionally catered for by wired communication systems. These technologies ensured high reliability and bandwidth but are however very expensive, inflexible and do not support mobility and pervasive monitoring. The communication protocols are Ethernet-based that used contention access protocols which results in high unsuccessful transmission and delay. An emerging class of wireless networks, named embedded wireless sensor and actuator networks has potential benefits for real-time monitoring and control of critical infrastructures. The use of embedded wireless networks for monitoring and control of critical infrastructures requires secure, reliable and timely exchange of information among controllers, distributed sensors and actuators. The exchange of information is over shared wireless media. However, wireless media is highly unpredictable due to path loss, shadow fading and ambient noise. Monitoring and control applications have stringent requirements on reliability, delay and security. The primary issue addressed in this dissertation is the impact of wireless media in harsh industrial environment on the reliable and timely delivery of critical data. In the first part of the dissertation, a combined networking and information theoretic approach was adopted to determine the transmit power required to maintain a minimum wireless channel capacity for reliable data transmission. The second part described a channel-aware scheduling scheme that ensured efficient utilization of the wireless link and guaranteed delay. Various analytical evaluations and simulations are used to evaluate and validate the feasibility of the methodologies and demonstrate that the protocols achieved reliable and real-time data delivery in wireless industrial networks.

Drosophila Flight Stabilization Depends on Apparent Distances in Optic Flow Field

To perform daily flight tasks, insects rely heavily on their visual perception of a dynamic environment. They must process visual signals quickly and accurately and update their behavior. Flies are vulnerable to environmental disturbances, such as gusts of wind blowing them off course, but they may use the altered visual field to compensate and regain their original course. In studies using Drosophila melanogaster, it has been shown that their corrective responses can be analyzed by measuring changes in their wing beats. By enclosing a tethered fly in a cuboidal visual arena displaying a computerized optic flow field, it is possible to calculate the change in wing beat amplitudes from an infrared shadow of its wings using photodiodes and a custom wing beat analyzer. In this experiment, manipulations ofthe optic flow field are used to create a field where points have varying relative forward speed, to study how the insect performs corrective maneuvers. The results show that Drosophila have a stronger corrective response to the quickly moving, apparently near points compared to the slower moving, apparently distant points. This implies the flies are distinguishing points based on their relative speeds, inferring distance, and adjusting their corrective actions with this information.

Israel, You Rascals

Mark Steel started doing stand-up in 1982 in England, around the circuit of bizarre gigs, going on after jugglers and escapologists and people that banged nails into their ear. Then came the Comedy Store and Jongleurs and getting bottled off at The Tunnel, and then a regular slot on Radio 4′s Loose Ends, where he met Joseph Heller, Christopher Lee and Gary Glitter. He did 4 series of ‘The Mark Steel Solution’, one for Radio 5 and the others on Radio 4, and a radio series about cricket, which provoked a whole page of fury in the Daily Express. He presented three series of a sports programme called ‘Extra Time’ which he was very proud of, especially as it went out on Tuesday nights on Radio 5 to possibly no listeners whatsoever. Then there was four series of the lectures on Radio 4, a book called ‘It’s Not a Runner Bean’, another one called ‘Reasons to be Cheerful’, and 3 television series of the lectures on BBC 4 and BBC 2. He has done weekly columns in Socialist Worker, the Guardian and the Independent. He has written a book called ‘Vive le Revolution’, and has been on various panel shows like Have I Got News For You and QI, and on Room 101, and on Question Time he says that he “got very confused when I insulted a member of the Tory shadow cabinet, and afterwards he said I was splendid and invited me for a drink.” And he’s spoken at lots of demonstrations and union meetings and protests, and appeared at quite a few benefits. This essay originally appeared on his website: http://marksteelinfo.com/blog/.

The creation of Huey P. Newton

The purpose of this study was to examine the creation of Huey P. Newton, founder of the Black Panther Party in 1966. I argued that Huey P. Newton was a creation of several elements: the black ghetto of Oakland; the rise of Black Power and the death of non-violence in the civil rights movement; the New Left and its factions; and, the Black Panther Party through the "Free Huey" campaign. The "Free Huey" campaign that arose from Newton's imprisonment in 1968, constructed an iconic image of Newton that he inherited on his release in 1970. This study will contextualize Newton and refute the claims of Hugh Pearson, author of the 1994, The Shadow of the Panther, who deemed Newton as a common criminal, not worthy of historical debate.

Determining polarization dependent diffraction coefficients from building edges using FDTD method

Electromagnetic waves in suburban environment encounter multiple obstructions that shadow the signal. These waves are scattered and random in polarization. They take multiple paths that add as vectors at the portable device. Buildings have vertical and horizontal edges. Diffraction from edges has polarization dependent characteristics. In practical case, a signal transmitted from a vertically polarized high antenna will result in a significant fraction of total power in the horizontal polarization at the street level. Signal reception can be improved whenever there is a probability of receiving the signal in at least two independent ways or branches. The Finite-Difference Time-Domain (FDTD) method was applied to obtain the two and three-dimensional dyadic diffraction coefficients (soft and hard) of right-angle perfect electric conductor (PEC) wedges illuminated by a plane wave. The FDTD results were in good agreement with the asymptotic solutions obtained using Uniform Theory of Diffraction (UTD). Further, a material wedge replaced the PEC wedge and the dyadic diffraction coefficient for the same was obtained.

Efeito da seca na dinâmica dos grupos funcionais fitoplanctônicos em reservatórios eutróficos do semiárido

Reservoirs are the main sources of surface water in Brazil´s semiarid region. The majority of these water supplies, however, are compromised by eutrophication. A severe drought in 2012 contributed to significant losses in water volume, influencing the availability of resources (nutrients and light) for phytoplankton. The aim of this study is to understand the dynamics of the functional groups of phytoplankton and the factors that affect them during a severe drought in the semiarid reservoirs of the northeast. We therefore studied the Dourado, Gargalheiras and Passagem das Traíras reservoirs in Rio Grande do Norte from January 2012 to January 2013. The effect of drought favoured homogeneity within the reservoir, in relation to biotic and abiotic variables, notably the absence of water supply given the lack of flow from its tributaries (intermittent river). The phytoplankton functional groups of bloomforming cyanobacteria (SN, S1 and M) dominated throughout the year 2012, in both the shallow and deep areas of the three reservoirs studied. The groups were related to high concentrations of volatile solids, total phosphorus and ammonia, and high turbidity. Cylindrospermopsis raciborskii (SN group) was the species with the greatest biomass in the three reservoirs. M group (Sphaerocavum brasiliense) performed better in shallow waters with more available phosphorus. Our data showed that high concentrations of nutrients and low availability of light, besides the stability of the water column due to lack of flow and the system´s high residence time, favoured the dominance of bloom-forming cyanobacteria groups, especially those tolerant to shadow

Entre Grande Otelo e Sebastião: tramas, representações e memórias

A versão impressa está dividida em volume 1 e 2.

Atomic nanolithography patterning of submicron features: writing an organic self-assembled monolayer with cold bright Cs atom beams

Cs atom beams, transversely collimated and cooled, passing through material masks in the form of arrays of reactive-ion-etched hollow Si pyramidal tips and optical masks formed by intense standing light waves, write submicron features on self-assembled monolayers (SAMs). Features with widths as narrow as 43 ± 6 nm and spatial resolution limited only by the grain boundaries of the substrate have been realized in SAMs of alkanethiols. The material masks write two-dimensional arrays of submicron holes; the optical masks result in parallel lines spaced by half the optical wavelength. Both types of feature are written to the substrate by exposure of the masked SAM to the Cs flux and a subsequent wet chemical etch. For the arrays of pyramidal tips, acting as passive shadow masks, the resolution and size of the resultant feature depends on the distance of the mask array from the SAM, an effect caused by the residual divergence of the Cs atom beam. The standing wave optical mask acts as an array of microlenses focusing the atom flux onto the substrate. Atom 'pencils' writing on SAMs have the potential to create arbitrary submicron figures in massively parallel arrays. The smallest features and highest resolutions were realized with SAMs grown on smooth, sputtered gold substrates.

From Where Do We Teach? Potential Positions in Public Education

This thesis is a conceptual examination of the positions from which we teach in public education. As it is philosophical in nature, it takes no qualitative or quantitative data. It offers a review of selected relevant literature and an analysis of personal and professional experience, with the intent to pose critical questions about teaching and learning. The framework of this thesis represents the following contentions: First, from its inception, public schooling served capital by preparing skilled labour for emerging industrial markets. This history is the hegemonic shadow that hangs over public education today. Second, movements toward the standardization of funding, curriculum, and evaluation support the further commodification of public schooling. The “accountability” that standardization offers, the “back to basics” that it aims for, is counter to the potential that public education might critically inform citizens and seek social justice. Third, movements toward the privatization of public schooling under the guise of “choice” and “mobility”, brought on by manufactured crisis, serve only to widen socio-economic inequities as capitalist neoliberal interests seek profit in both the product of public schools and in schooling itself. If we recognize and understand the power of public education to inform vast numbers of citizens who will, in turn, either maintain or reform society, we must ask: What do we want public education to be? What are the effects of continuing down historically conventional and increasingly standardized paths? What do progressive pedagogies offer? How might teachers destandardize their pedagogy and pursue equitable opportunities for marginalized students? How might students name themselves and their world, that they might play a part in its reimagining? For whom do we teach, and under what conditions? From where do we teach, and why? For educators to ask these questions, and to employ what they discover, will necessitate taking substantial risks. It will necessitate taking a stand and cannot be done alone. Teachers must seek out the collaboration of their students. They must offer students the time and the space to find their own voices, to create their own selves, and to envision previously uncharted paths on which we might walk together.

Default Invariance: Naïve Category of Law and Finance

Default invariance is the idea that default does not change at any scale of law and finance. Default is a conserved quantity in a universe where fundamental principles of law and finance operate. It exists at the micro-level as part of the fundamental structure of every financial transaction, and at the macro- level, as a fixed critical point within the relatively stable phases of the law and finance cycle. A key point is that default is equivalent to maximizing uncertainty at the micro-level and at the macro-level, is equivalent to the phase transition where unbearable fluctuations occur in all forms of risk transformation, including maturity, liquidity and credit. As such, default invariance is the glue that links the micro and macro structures of law and finance. In this essay, we apply naïve category theory (NCT), a type of mapping logic, to these types of phenomena. The purpose of using NCT is to introduce a rigorous (but simple) mathematical methodology to law and finance discourse and to show that these types of structural considerations are of prime practical importance and significance to law and finance practitioners. These mappings imply a number of novel areas of investigation. From the micro- structure, three macro-approximations are implied. These approximations form the core analytical framework which we will use to examine the phenomena and hypothesize rules governing law and finance. Our observations from these approximations are grouped into five findings. While the entirety of the five findings can be encapsulated by the three approximations, since the intended audience of this paper is the non-specialist in law, finance and category theory, for ease of access we will illustrate the use of the mappings with relatively common concepts drawn from law and finance, focusing especially on financial contracts, derivatives, Shadow Banking, credit rating agencies and credit crises.

Gravity collapse structures in the Central Precordillera fold-andthrust belt, Argentina

Several landforms found in the fold-and-thrust belt area of Central Precordillera, Pre-Andes of Argentina, which were often associated with tectonic efforts, are in fact related to non-tectonic processes or gravitational superficial structures. These second-order structures, interpreted as gravitational collapse structures, have developed in the western flank of sierras de La Dehesa and Talacasto. These include rock-slides, rock falls, wrinkle folds, slip sheets and flaps, among others; which together constitute a monoclinal fold dipping between 30º and 60º to the west. Gravity collapse structures are parallel to the regional strike of the Sierra de la Dehesa and are placed in Ordovician limestones and dolomites. Their sloping towards the west, the presence of bed planes, fractures and joints; and the lithology (limestone interbedded with incompetent argillaceous banks) would have favored their occurrence. Movement of the detached structures has been controlled by lithology characteristics, as well as by bedding and joints. Detachment and initial transport of gravity collapse structures and rockslides in the western flank of the Sierra de la Dehesa were tightly controlled by three structural elements: 1) sliding surfaces developed on parallel bedded strata when dipping >30° in the slope direction; 2) Joint’s sets constitute lateral and transverse traction cracks which release extensional stresses and 3) Discontinuities fragmenting sliding surfaces.  Some other factors that could be characterized as local (lithology, structure and topography) and as regional (high seismic activity and possibly wetter conditions during the postglacial period) were determining in favoring the steady loss of the western mountain side in the easternmost foothills of Central Precordillera.

Organizaciones regionales y diversidad cultural: la diplomacia de la Unión Europea con el Mercosur entre la sombra de Hollywood y la acción intergubernamental

El objetivo de este artículo es doble: por un lado explorar la habilidad de la Unión Europea para llevar a cabo una política audiovisual dirigida al Mercosur y promover las normas de la Convención sobre la diversidad de las expresiones culturales; por otro, analizar el impacto del modelo de política audiovisual de la UE en el desarrollo de la cooperación audiovisual con el Mercosur y centrarse en los principales vectores que configuran el paisaje audiovisual del Mercosur. El texto pretende destacar cómo y por qué la UE persigue una política audiovisual con esa región, cuáles son los propósitos y los límites de actuación. En este sentido, se preocupa por entender cómo la diplomacia audiovisual de la UE interactúa con otros actores, como las acciones gubernamentales llevadas a cabo desde la propia UE y el Mercosur, así como las prácticas del sector privado (Hollywwod y los grandes conglomerados de medios).

Crisis communication in politics: forgiveness as image restoration tool

Crisis communication is a widely treated field. There are lot of works and guides which provide helpful information in order to face crisis situations successfully (Alcat, 2005, Benoit, 1997) and articles about case studies (Nespereira, 2014, Blaney y Benoit 2001). Nonetheless, most of times, these guides are focused on business or corporations (Abeler, 2010) and there are not such information about crisis communications in politics (Gaspar e Ibeas, 2015). The field is smaller if we speak about forgiveness as restoration image tool in politics (Harris 2006). Despite all, we live in “forgiveness era” as Krauze said (1998) where people demand to politicians to apologize when they have mistakes (Harris et al. 2006:716). So, we will try to make an approach to forgiveness in politics as a image restoration tool and analyze its capabilities in order to face crisis management.

GIS technologies and spatial organization patterns among hunter-gatherers: an archaeological case study from Southern Patagonia (southern South America)

This paper discusses some aspects of hunter-gatherer spatial organization in southern South Patagonia, in later times to 10,000 cal yr BP. Various methods of spatial analysis, elaborated with a Geographic Information System (GIS) were applied to the distributional pattern of archaeological sites with radiocarbon dates. The shift in the distributional pattern of chronological information was assessed in conjunction with other lines of evidence within a biogeographic framework. Accordingly, the varying degrees of occupation and integration of coastal and interior spaces in human spatial organization are explained in association with the adaptive strategies hunter-gatherers have used over time. Both are part of the same human response to changes in risk and uncertainty variability in the region in terms of resource availability and environmental dynamics.