Exhibit: "Michigan-I-O": Alan Lomax and the 1938 Library of Congress Folk-Song Expedition"

In 1938, a young folk music collector named Alan Lomax—destined to become one of the legendary folklorists of the 20th century recorded Michigan’s richly varied folk music traditions for the Archive of American Folk-Song at the Library of Congress. Michigan in the 1930s was experiencing a golden age of folksong collecting, as local folklorists mined the trove of ballads remembered by aging lumbermen and Great Lakes schoonermen. In addition to the ballads of these north woods singers, Lomax recorded a vibrant mix of ethnic music from Detroit to the western Upper Peninsula. The multimedia performance event Folksongs from Michigan-i-o combines live performance with historic images, color movie footage, and recorded sound from the Great Depression. Some of these materials haven’t been heard or seen by the general public for more than seven decades. The traveling exhibition Michigan Folksong Legacy: Grand Discoveries from the Great Depression brings Alan Lomax’s 1938 field trip to life through words, song lyrics, photographs, and sound recordings. Ten interpretive banners explore themes and each panel contains a QR code that links to related sound recordings from the Alan Lomax Collection at the American Folklife Center, Library of Congress.

Exhibit: "Michigan-I-O": Alan Lomax and the 1938 Library of Congress Folk-Song Expedition"

In 1938, a young folk music collector named Alan Lomax—destined to become one of the legendary folklorists of the 20th century recorded Michigan’s richly varied folk music traditions for the Archive of American Folk-Song at the Library of Congress. Michigan in the 1930s was experiencing a golden age of folksong collecting, as local folklorists mined the trove of ballads remembered by aging lumbermen and Great Lakes schoonermen. In addition to the ballads of these north woods singers, Lomax recorded a vibrant mix of ethnic music from Detroit to the western Upper Peninsula. The multimedia performance event Folksongs from Michigan-i-o combines live performance with historic images, color movie footage, and recorded sound from the Great Depression. Some of these materials haven’t been heard or seen by the general public for more than seven decades. The traveling exhibition Michigan Folksong Legacy: Grand Discoveries from the Great Depression brings Alan Lomax’s 1938 field trip to life through words, song lyrics, photographs, and sound recordings. Ten interpretive banners explore themes and each panel contains a QR code that links to related sound recordings from the Alan Lomax Collection at the American Folklife Center, Library of Congress.

Exhibit: "Michigan-I-O": Alan Lomax and the 1938 Library of Congress Folk-Song Expedition

In 1938, a young folk music collector named Alan Lomax—destined to become one of the legendary folklorists of the 20th century recorded Michigan’s richly varied folk music traditions for the Archive of American Folk-Song at the Library of Congress. Michigan in the 1930s was experiencing a golden age of folksong collecting, as local folklorists mined the trove of ballads remembered by aging lumbermen and Great Lakes schoonermen. In addition to the ballads of these north woods singers, Lomax recorded a vibrant mix of ethnic music from Detroit to the western Upper Peninsula. The multimedia performance event Folksongs from Michigan-i-o combines live performance with historic images, color movie footage, and recorded sound from the Great Depression. Some of these materials haven’t been heard or seen by the general public for more than seven decades. The traveling exhibition Michigan Folksong Legacy: Grand Discoveries from the Great Depression brings Alan Lomax’s 1938 field trip to life through words, song lyrics, photographs, and sound recordings. Ten interpretive banners explore themes and each panel contains a QR code that links to related sound recordings from the Alan Lomax Collection at the American Folklife Center, Library of Congress.

Ultraviolet digital imaging of volcanic plumes : implementation and application to magmatic processes at basaltic volcanoes

Magmatic volatiles play a crucial role in volcanism, from magma production at depth to generation of seismic phenomena to control of eruption style. Accordingly, many models of volcano dynamics rely heavily on behavior of such volatiles. Yet measurements of emission rates of volcanic gases have historically been limited, which has restricted model verification to processes on the order of days or longer. UV cameras are a recent advancement in the field of remote sensing of volcanic SO2 emissions. They offer enhanced temporal and spatial resolution over previous measurement techniques, but need development before they can be widely adopted and achieve the promise of integration with other geophysical datasets. Large datasets require a means by which to quickly and efficiently use imagery to calculate emission rates. We present a suite of programs designed to semi-automatically determine emission rates of SO2 from series of UV images. Extraction of high temporal resolution SO2 emission rates via this software facilitates comparison of gas data to geophysical data for the purposes of evaluating models of volcanic activity and has already proven useful at several volcanoes. Integrated UV camera and seismic measurements recorded in January 2009 at Fuego volcano, Guatemala, provide new insight into the system’s shallow conduit processes. High temporal resolution SO2 data reveal patterns of SO2 emission rate relative to explosions and seismic tremor that indicate tremor and degassing share a common source process. Progressive decreases in emission rate appear to represent inhibition of gas loss from magma as a result of rheological stiffening in the upper conduit. Measurements of emission rate from two closely-spaced vents, made possible by the high spatial resolution of the camera, help constrain this model. UV camera measurements at Kilauea volcano, Hawaii, in May of 2010 captured two occurrences of lava filling and draining within the summit vent. Accompanying high lava stands were diminished SO2 emission rates, decreased seismic and infrasonic tremor, minor deflation, and slowed lava lake surface velocity. Incorporation of UV camera data into the multi-parameter dataset gives credence to the likelihood of shallow gas accumulation as the cause of such events.

LOCAL DIGITAL CONTROL OF POWER ELECTRONIC CONVERTERS IN A DC MICROGRID BASED ON A-PRIORI DERIVATION OF SWITCHING SURFACES

In power electronic basedmicrogrids, the computational requirements needed to implement an optimized online control strategy can be prohibitive. The work presented in this dissertation proposes a generalized method of derivation of geometric manifolds in a dc microgrid that is based on the a-priori computation of the optimal reactions and trajectories for classes of events in a dc microgrid. The proposed states are the stored energies in all the energy storage elements of the dc microgrid and power flowing into them. It is anticipated that calculating a large enough set of dissimilar transient scenarios will also span many scenarios not specifically used to develop the surface. These geometric manifolds will then be used as reference surfaces in any type of controller, such as a sliding mode hysteretic controller. The presence of switched power converters in microgrids involve different control actions for different system events. The control of the switch states of the converters is essential for steady state and transient operations. A digital memory look-up based controller that uses a hysteretic sliding mode control strategy is an effective technique to generate the proper switch states for the converters. An example dcmicrogrid with three dc-dc boost converters and resistive loads is considered for this work. The geometric manifolds are successfully generated for transient events, such as step changes in the loads and the sources. The surfaces corresponding to a specific case of step change in the loads are then used as reference surfaces in an EEPROM for experimentally validating the control strategy. The required switch states corresponding to this specific transient scenario are programmed in the EEPROM as a memory table. This controls the switching of the dc-dc boost converters and drives the system states to the reference manifold. In this work, it is shown that this strategy effectively controls the system for a transient condition such as step changes in the loads for the example case.