Low recruitment is the largest challenge facing the recovery of the critically endangered Mississippi Sandhill Crane (Grus canadensis pulla). Lack of information on sources of nest failure hinders effective management to increase recruitment. I examined sources of nest failure for 54 nests at the Mississippi Sandhill Crane National Wildlife Refuge, 2008-2009. Nest cameras identified predation as the primary source of failure, followed by flooding, abandonment, and egg inviability. Mean daily survival rate (DSR) was 0.72. The best approximating models included covariates for season date, temperature and nest age. DSR decreased with increasing season date, increasing nest age, and decreasing temperature. Hypotheses related to effects of renesting, human disturbance, precipitation, flooding, and winter rain were not supported. Because predation has been identified as a primary source of nest failure, I also monitored mammalian predators on the MSCNWR. Coyotes and raccoons were most common, with gray foxes, red foxes, domestic dogs, and bobcats also detected frequently.

The genetic status of the critically endangered Mississippi sandhill crane (Grus canadensis pulla) was analyzed using 2009 studbook data from the U.S. Fish and Wildlife Service managed captive breeding and release program. Microsatellite DNA data provided information on shared founder genotypes, allowing for refined analysis of genetic variation in the population, and informed breeding recommendations. The genetic variation observed in the Mississippi sandhill crane was contrasted with variation observed in the Florida sandhill crane (Grus canadensis pratensis). Results show far less variation in the Mississippi population. Results also suggest that while gene flow no longer occurs between the two populations, the introduction of cranes from the Florida population would help to increase the observed genetic diversity of the Mississippi sandhill crane population.

This study describes a method for conducting the structural dynamic analysis of a crane fly (family Tipulidae) forewing under different airflow conditions. Wing geometry is captured via micro-computed tomography scanning. A finite element model of the forewing is developed from the reconstructed model of the scan. The finite element model is validated by comparing the natural frequencies of an elliptical membrane with similar dimensions of the crane fly forewing to its analytical solution. Furthermore, a simulation of the fluid-structure interaction of the forewing under different airflows is performed by coupling the finite element model of the wing with a computation fluid dynamics model. From the finite element model, the mode shapes and natural frequencies are investigated; similarly, from the fluid-structure interaction, the time-varying out-of-plane deformation, and the coefficients of drag and lift are determined.

Thesis advisor: Carlo Rotella / Addressing a gathering of social scientists at Boston’s Lowell Institute in 1870, Frederic Law Olmsted worried that the "restraining and confining conditions" of the American city compelled its inhabitants to "walk circumspectly, watchfully, jealously" and to "look closely upon others without sympathy." Olmsted was telling his audience what many had already been saying, and would continue to say, about urban life: sympathy was hard to come by in the city. The urban intellectuals that I examine in this study view with greater optimism the affective possibilities of the city’s social landscape. Rather than describe the city as a place that necessarily precludes or interferes with the sympathetic process, late-nineteenth- and twentieth-century urban intellectuals such as Stephen Crane, Jane Addams, W. E. B. Du Bois, Joseph Mitchell, A. J. Liebling and Jane Jacobs attempt to redefine the nature of that process. Their descriptions of urban relationships reconfigure the affective patterns that lay at the heart of a sentimental culture of sympathy—patterns that had remained, in many ways, deeply connected to those described by Adam Smith and other eighteenth-century moral philosophers. This study traces the development of what I call "urban sympathy" by demonstrating how observers of city life translate received literary and nonliterary idioms into cultural forms that capture the everyday emotions and obligations arising in the city’s small-scale contact zones—its streets, sidewalks, front stoops, theaters, cafes and corner stores. Urban Sympathy calls attention to the ways in which urban intellectuals with different religious, racial, economic, scientific and professional commitments urbanize the social project of a nineteenth-century sentimental culture. Rather than view the sympathetic exchange as dependent upon access to another’s private feelings, these writers describe an affective process that deals in publicly traded emotions. Where many see the act of identification as sympathy’s inevitable product, these observers of city life tend to characterize an awareness and preservation of differences as urban sympathy’s outcome. While scholars traditionally criticize the sympathetic process for ignoring the larger social structures in which its participants are entangled, several of these writers cultivate a sympathetic style that attempts to account for individuals and the larger social, economic and political forces that shape them. / Thesis (PhD) — Boston College, 2008. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: English.

The skyline of many 'world cities' are defined and punctuated by tall buildings. The drivers for such dominant skylines range from land scarcity and social needs; high real estate values; commercial opportunity and corporate demand, through to metropolitan signposting. This fascination with tall buildings started with the patrician families who created the 11th Century skyline of San Gimignano by building seventy tower-houses (some up to 50m tall) as symbols of their wealth and power. This was most famously followed in the late 19th Century with the Manhattan skyline, then Dubai building the world's highest building, then China building some eighty tall buildings completed in the last 5 years, then UK building Europe's highest tower, the Shard and finally back to Dubai, planning a kilometre tall tower, potentially realising Ludwig Mies van der Rohe's 'Impossible Dream' of the 1920's and Frank Lloyd Wright's 1956 'Mile High Illinois'. This ambition to build higher and higher continues to challenge the Architects, Engineers and Builders of tall buildings and is expected to continue into the future. The tall building format is clearly here to stay.

La presencia de puentes grúa en naves industriales significa un esfuerzo adicional para la estructura de la nave debido a las solicitaciones de carga adicionales que ésta representa. Así, se requiere un análisis específico y completo para diseñar una estructura resistente a los esfuerzos generados por la carga proveniente del puente-grúa. El objetivo de este artículo es elaborar un documento que sirva como guía para un correcto análisis y diseño de la viga que sostiene al puente-grúa, conocida como viga carrilera; lo anterior a partir de la comparación de normativas de algunos países latinoamericanos y la norma norteamericana. Este análisis incluye el conjunto de esfuerzos generados por la operación de un puente-grúa. Finalmente, la propuesta o método se validará con un ejemplo de puente grúa de capacidad de izaje de hasta 10 toneladas. / The presence of travelling cranes in industrial buildings means an additional effort for the structure of the ship due to the additional loads. Thus, a specific and complete analysis is required, both static and dynamic, to design a structure resistant to the efforts generated by the load coming from the travelling crane. The objective of this article is to elaborate a document that serves as a guide for a correct analysis and design of the beam that supports the travelling crane, known as the rail beam; from the comparison of regulations of some Latin American countries and the North American norms. This analysis includes the set of efforts generated by the operation of a bridge crane. Finally, the proposal or method will be validated with an example of a crane lifting capacity of up to 10 tons. / Trabajo de investigación

<p>Atlas Copco Surface Drilling Equipment is one of the leading manufacturers of surface drill rigs. To stay in the top segment it is of great importance to have a well functioning development strategy as well as rig functions that makes the work as easy as possible for the operator. In this master thesis one development strategy has been evaluated and a dub tip control has been developed from idea to test on rig.</p><p> </p><p>Today the conventional method to position the drill is to use two joysticks with three axes each where each axis corresponds to one hydraulic actuator on the boom and feeder structure. The dub tip control system enables the operator to position the drill in Cartesian coordinates with only one 3-axes joystick. After the definition of the desired drill angle is done, the control system makes sure that this angle is obtained throughout the positioning motion. This system makes it considerably easier for an inexperienced operator to position the drill.</p><p> </p><p>For development, simulation and verification of the control algorithms and regulators <em>Matlab/Simulink</em> has been used. To test the control system on rig, a configuration with <em>LabVIEW</em> together with a <em>compactDAQ</em> has been evaluated. <em>LabVIEW </em>is chosen because it provides the opportunity to create a user friendly graphical user interface. To use this configuration is however not recommended for persons with little or none experience from using <em>LabVIEW</em>.</p><p> </p><p>This development strategy can be used for tests and verifications of control algorithms, but since neither <em>Windows </em>nor the <em>compactDAQ </em>are real time systems, there are solutions that are better but of course to a higher price.</p><p> </p><p>The master thesis work has shown that it is possible to implement a dub tip control on a rig of this dimension. It has also concluded that compensated valves are necessary to achieve optimal performance of a velocity controlled dub tip positioning.</p>

The allocation of resources over time, referred to as resource scheduling, in large-scale construction environments is a challenging problem. Although traditional network scheduling techniques are the most popular scheduling techniques in the construction industry, they are ineffective in modeling the dynamic nature and resource interactions of large projects. Simulation based modeling or optimization techniques are also time-consuming, complicated and costly to be implemented in large-scale projects. This research is focused on developing a new framework to insert artificial intelligence inside construction simulations for facilitating the resource allocation process. The first stage in this study was developing a framework to solve resource scheduling problems in large scale construction projects. This framework, called the Simulation Based Auction Protocol (SBAP), integrates Multi-Agent Resource Allocation (MARA) in a simulation environment. This hybrid framework deploys centralized MARA (i.e., auction protocols) whereby agents bid on different combinations of resources at the start of a simulation cycle. Agents attempt to improve their individual welfare by acquiring a combination of resources. An auctioneer is designed to allocate resources to the agents by maximizing the overall welfare of the society. Simulation is also employed to track the availability of resources, and manage resource oriented activities. This framework is implemented in two large construction applications of scheduling module assembly yard and multiple heavy lift planning in modular construction. The second objective of this project is to develop a generic resource allocation component for addressing optimized resource allocation in various construction projects. This component is developed in a large scale model using High Level Architecture (HLA), instead of traditional simulation environments. HLA allows splitting a large scale model, known as a federation, into a number of manageable components (i.e., federates), while maintaining interoperability between them. A generic Resource Allocation (RA) federate is designed to act as an auctioneer for federates developed based on the SBAP. Another generic federate is also built to automate the communication with the RA federate. These two generic federates can be reused in various construction federations. This framework is successfully implemented in an industrial construction process that involves different supply chains including spool fabrication, module assembly and heavy crane lifts in site construction. / Construction Engineering and Management

Atlas Copco Surface Drilling Equipment is one of the leading manufacturers of surface drill rigs. To stay in the top segment it is of great importance to have a well functioning development strategy as well as rig functions that makes the work as easy as possible for the operator. In this master thesis one development strategy has been evaluated and a dub tip control has been developed from idea to test on rig.   Today the conventional method to position the drill is to use two joysticks with three axes each where each axis corresponds to one hydraulic actuator on the boom and feeder structure. The dub tip control system enables the operator to position the drill in Cartesian coordinates with only one 3-axes joystick. After the definition of the desired drill angle is done, the control system makes sure that this angle is obtained throughout the positioning motion. This system makes it considerably easier for an inexperienced operator to position the drill.   For development, simulation and verification of the control algorithms and regulators Matlab/Simulink has been used. To test the control system on rig, a configuration with LabVIEW together with a compactDAQ has been evaluated. LabVIEW is chosen because it provides the opportunity to create a user friendly graphical user interface. To use this configuration is however not recommended for persons with little or none experience from using LabVIEW.   This development strategy can be used for tests and verifications of control algorithms, but since neither Windows nor the compactDAQ are real time systems, there are solutions that are better but of course to a higher price.   The master thesis work has shown that it is possible to implement a dub tip control on a rig of this dimension. It has also concluded that compensated valves are necessary to achieve optimal performance of a velocity controlled dub tip positioning.

In 2002, a proposal was submitted to divert water from the confluence of the Guadalupe and San Antonio Rivers to San Antonio, Texas. To investigate the potential impacts of diverting water from the Guadalupe Estuary, my research focused on the foraging ecology of the crane and population ecology of the blue crab, a documented crane food. During winters 2004-2005 and 2005-2006, I examined diets and optimal foraging patterns of territorial adult cranes at Aransas National Wildlife Refuge, Texas. To identify foods of greatest benefit to cranes, I used currencies of optimization to evaluate foraging gain, cost, and efficiency. Foraging benefit differed among foods, depending on the foraging currency used and resource targeted (e.g., energy). Wolfberry fruit, snails, and insects were consumed in the highest quantities, required the least foraging effort, and were generally associated with the highest foraging efficiency. Blue crabs and clams were important sources of protein and biomass. During September 2003-October 2005, I used novel artificial settlement substrates and modified methods of standard deployment to investigate the spatio-temporal patterns of blue crab terminal settlement and recruitment rates. Monitoring rates in shallow bay habitat and ponds of the interior salt-marsh revealed megalopal crabs were developmentally advanced when arriving to study sites and the extent to which young crabs infiltrated the salt-marsh increased with age. Such findings suggested sites represented optimal terminal settlement habitat and consequently critical nursery habitat. Model selection indicated water temperature before and during embryonic development was the best predictor of megalopal settlement, whereas juvenile recruitment was most influenced by recent precipitation. I studied the size-specific abundance patterns of blue crabs in and around mature salt-marsh. Using drop-trapping and throw-trapping methods, I collected monthly samples in several habitats during October 2004-March 2006. Interior-marsh habitats contained fewer but larger crabs than bay habitat. Crabs contributing greatest to biomass were smallest (11-30 mm carapace-width) in bay habitat, larger (31-80 mm) along interior-marsh pond edges, and largest (41-130 mm) in interior-marsh open water. Model selection revealed crab density was most influenced by micro-site characteristics (habitat, water column structure type and structural complexity). Overall, shallow bay provided important nursery habitat for young blue crabs and interior marsh ponds were important for dispersing juvenile and adult crabs.