4,167 research outputs found
Migratory responses to agricultural risk in Northern Nigeria
We investigate the extent in which northern Nigerian households engage in internal migration to insure against ex ante and ex post agricultural risk due to weather-related variability and shocks. We use data on the migration patterns of individuals over a 20-year period and temperature degree-days to identify agricultural risk. Controlling for ex ante and ex post risk, we find that households with higher ex ante risk are more likely to send migrants. Households facing hot shocks before the migrant’s move tend to keep their male migrants in closer proximity. These findings suggest that households use migration as a risk management strategy in response to both ex ante and ex post risk, but that migration responses are gender-specific. These findings have implications not only for understanding the insurance motives of households, but also potential policy responses tied to climatic warming.Migration, Risk, temperature degree days,
“Art Hurts”: Intimacy, Difficulty, and Distance in Gwendolyn Brooks’s “Two Dedications”
In this thesis, I examine Gwendolyn Brooks’s diptych poems “Two Dedications” from her 1968 collection In the Mecca. Critical accounts of “Two Dedications” cast the poems as fixed oppositions between “frivolous” Western art and inspiring, communal black art. I propose that such binaries are reductive and overlook the intellectual benefits Brooks locates in abstract modernist art. Using Ezra Pound’s theories of modernist difficulty, Walter Benjamin’s concept of artistic “aura,” and the Black Arts Movement (BAM) manifestoes of Ron Karenga and Larry Neal, I argue that Brooks’s poems demonstrate the benefits of both abstract Western art and representational BAM art. Specifically, Brooks suggests that both types of art provide avenues for self-determination and liberation from institutional conventions
Fortune and Failure - Gold and Silver Smelting in the Colorado Rockies 1861 to 1900
This dissertation is a study of small-scale smelting in Colorado during the nineteenth century. Many small smelting enterprises were established throughout the mountains of the state from the mid-1860s to the mid-1880s. The smelters helped to revitalize a flagging mining industry by fostering its growth and, consequently, the development of the state before being outcompeted by larger smelting establishments developing in the growing cities on the Front Range. However, the life of these smelters was brief, and the majority failed within a few years. The role of these smelters in Colorado’s history has been largely overlooked but provide a rich potential to contribute to our knowledge of Colorado history, and scientific studies relevant to contemporary society including rural economic development, technology transfer, sustainability, and the ecological impacts of industrial enterprises.
The primary pattern within the small-scale smelting industry of Colorado was one of failure. The study of the reasons for the failure of the small smelting businesses forms the main topic of this dissertation. These smelters required a specific set of conditions to survive, grew in isolated areas with difficult access, and failed when their isolation was ended by improved transportation, which opened their region to outside competition. Although there were many facets contributing to the failure of these smelters, competition from larger businesses is the main culprit as the small smelters could not compete with better capitalized and more efficient large smelters once their niche market was incorporated into the larger economic sphere of the state
Preventing Parkland: A Workable Fourth Amendment Standard for Searching Juveniles\u27 Smartphones Amid School Threats in a Post-Parkland World
On February 14, 2018, Nikolas Cruz, age nineteen, went to the Marjory Stoneman Douglas High School campus in Parkland, Florida, armed with an AR-15 rifle. He opened fire, killing seventeen students. His unspeakable actions culminated in an attack, which eclipsed the 1999 Columbine High School Massacre to become the deadliest school shooting at a high school in American history. In the immediate months following this still-recent tragedy, schools across the United States were flooded with “copycat” threats of violence. Terroristic threat charges levied against juveniles have likewise skyrocketed.
These recent events have resulted in new and burdensome pressures for schools and juveniles alike. In an age in which smart phones and social media are ubiquitous hallmarks of American youth culture, saturating nearly every grade level and socioeconomic stratum, schools must respond to the contemporary and evolving challenge of maintaining school safety amid threats prepared and delivered on smartphone accessible apps like Twitter, Instagram, and Snapchat. Law enforcement officials, at the behest of school officials whose chief concern is to prevent the next “Parkland,” appear to be addressing this issue aggressively and charging juveniles with more crimes than before. Whereas a search of a student’s locker, backpack, or notebook used to suffice, she now carries a smartphone capable of storing, transmitting, and accessing private information and ideas, which exist far beyond the physical form of the device itself. Even when students’ Fourth Amendment rights have been curtailed by a warrantless search of her belongings, rightly or wrongly, courts have been unwilling to tip the scales against school administrators—but smartphones complicate the matter.
This Comment promotes a compromise aimed at addressing two timely and related concerns: protecting students’ safety and defending students’ privacy. First, the Supreme Court should enunciate a new standard for searching students’ smartphones on school grounds. A new standard will provide clarity for school officials and students alike and will illuminate acceptable circumstances that warrant abridging students’ Fourth Amendment rights in the name of keeping schools safe. It will also make clear when searches of students’ smartphones become unreasonable and violative of the Constitution. Second, this Comment suggests one policy schools should adopt to best maintain school safety, curb threats, and protect students’ Fourth Amendment rights with respect to their smartphones. These proposals taken together will assist schools in addressing and curtailing smartphone-generated threats directed at students, faculty, and administrators, while simultaneously reducing the number of charges levied against juveniles in a post-Parkland America
Analyses of building energy system alternatives through transient simulation
This thesis examines the performance of residential buildings and the energy systems contained within those buildings by simulating them in the TRaNsient SYstems Simulation (TRNSYS) program. After matching a building's floorplan to that of house local to the College Park area, national and local building surveys were consulted to produce a prototype of the average Maryland home. This home was simulated with ordinary insulation levels, heating, ventilation, and air conditioning (HVAC) equipment, and appliances. Various construction characteristics, including wall insulation, thermostat set points, HVAC equipment, and appliance efficiency were varied to examine the effects of each individual change upon the final annual energy consumption of the building, and in doing so, the value of retrofitting each characteristic was explored. Finally, the most effective energy-saving strategies were combined to model a low-energy home, in order to explore the possibility of refitting an existing home to become a net-zero site energy building. Sensitivity study results were listed, and a net-zero-energy building was successfully simulated
Land use restrictions and household transportation choice
2016 Fall.Includes bibliographical references.The primary objective of the dissertation is to further existing research on the link between the built environment and travel behavior. The dissertation proposes to make this advance in two distinct ways. First, by testing the impact of land use regulation on travel behavior by incorporating zoning restrictions as an exogenous variable in the model. Second, by explicitly modeling spatial variation in the discrete choice of mode of transportation. The dissertation is organized into three chapters. The first develops a multinomial discrete choice model that addresses unobserved travel preferences by incorporating sociodemographic, built environment, and land use restriction variables. The second builds upon the first by explicitly modeling spatial dependence of travel mode choice in a and compares the results of models from the first and second chapters to address the effect of spatial dependence on travel behavior-built environment model estimates. The third reviews previous models and theories related to land use restrictions, and reviews the economic and policy implications of findings from the first two chapters
Frogeye Leaf Spot Resistance in Soybean
Isolates of Cercospora sojina showing reduced sensitivity to quinone outside inhibitor (QoI, strobilurin) fungicides were recently recovered from soybean in Iowa. This pathogen causes frogeye leaf spot, an important foliar soybean disease that can be managed with fungicides. With the confirmation of fungicide-resistant isolates, it becomes especially important to understand when to spray and what products to use for long-term control of this disease
MoSculp: Interactive Visualization of Shape and Time
We present a system that allows users to visualize complex human motion via
3D motion sculptures---a representation that conveys the 3D structure swept by
a human body as it moves through space. Given an input video, our system
computes the motion sculptures and provides a user interface for rendering it
in different styles, including the options to insert the sculpture back into
the original video, render it in a synthetic scene or physically print it.
To provide this end-to-end workflow, we introduce an algorithm that estimates
that human's 3D geometry over time from a set of 2D images and develop a
3D-aware image-based rendering approach that embeds the sculpture back into the
scene. By automating the process, our system takes motion sculpture creation
out of the realm of professional artists, and makes it applicable to a wide
range of existing video material.
By providing viewers with 3D information, motion sculptures reveal space-time
motion information that is difficult to perceive with the naked eye, and allow
viewers to interpret how different parts of the object interact over time. We
validate the effectiveness of this approach with user studies, finding that our
motion sculpture visualizations are significantly more informative about motion
than existing stroboscopic and space-time visualization methods.Comment: UIST 2018. Project page: http://mosculp.csail.mit.edu
Characterization of the probabilistic models that can be embedded in quantum theory
Quantum bits can be isolated to perform useful information-theoretic tasks,
even though physical systems are fundamentally described by very
high-dimensional operator algebras. This is because qubits can be consistently
embedded into higher-dimensional Hilbert spaces. A similar embedding of
classical probability distributions into quantum theory enables the emergence
of classical physics via decoherence. Here, we ask which other probabilistic
models can similarly be embedded into finite-dimensional quantum theory. We
show that the embeddable models are exactly those that correspond to the
Euclidean special Jordan algebras: quantum theory over the reals, the complex
numbers, or the quaternions, and "spin factors" (qubits with more than three
degrees of freedom), and direct sums thereof. Among those, only classical and
standard quantum theory with superselection rules can arise from a physical
decoherence map. Our results have significant consequences for some
experimental tests of quantum theory, by clarifying how they could (or could
not) falsify it. Furthermore, they imply that all unrestricted non-classical
models must be contextual.Comment: 6 pages, 0 figure
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