Buildup and Infill Rates of Sediment Behind Cedarcliff Falls Dam

Cedarcliff Falls Dam is a small man-made masonry dam that was constructed around 1869. The dam impounds a pool of water that is a half-mile long on Massie’s Creek near Cedarville, Ohio. This project’s goal was to ascertain the infill rate and character of the sediment that had built up since 1869. The field work involved the measurement of water depth through the length of the pool in order to create a bottom-contour map. In addition, the sediment type was examined throughout the pool. This work was accomplished by use of a boat, stadia rod, handheld GPS unit, and a Ponar grab sampler. The contour map was created, and the volume of water in the pool was calculated, using Surfer 8 software. Sediment type was determined by “feel” with the stadia rod and by collecting samples with the Ponar grab sampler. Historical information is lacking for determining sediment influx from significant past hydrologic events. Potential sediment sources feeding the pool include agricultural and construction derived materials, and normal-natural and flood-natural materials. The bottom of the pool has an undulating character along its course and varying sediment types. The deepest area found was twenty-three feet and the shallowest was five feet. The upstream lithology is predominantly dolomite, but the entire area is overlain by glacial drift. The irregular distribution of sediment types seems to be associated with the nature of the creek bank at any particular location. Depth variation within the pool appears to be associated with the width of the channel, with depth being inversely correlated to width. Results from this study could affect land use planning around the creek and could also influence the assessment of the long-term viability of the dam

The Invincible (1758) site: an integrated geophysical assessment

Chirp sub-bottom profiler and repeat sidescan sonar imaging of the Invincible wreck site (1758) in the Solent (U.K.), interpretation, and implications for management of the site

Trade Reform and Regional Dynamics: Evidence From 25 Years of Brazilian Matched Employer-Employee Data

We empirically study the dynamics of labor market adjustment following the Brazilian trade reform of the 1990s. We use variation in industry-specific tariff cuts interacted with initial regional industry mix to measure trade-induced local labor demand shocks, and then examine regional and individual labor market responses to those one-time shocks over two decades. Contrary to conventional wisdom, we do not find that the impact of local shocks is dissipated over time through wage-equalizing migration. Instead, we find steadily growing effects of local shocks on regional formal sector wages and employment for 20 years. This finding can be rationalized in a simple equilibrium model with two complementary factors of production, labor and industry-specific factors such as capital, that adjust slowly and imperfectly to shocks. Next, we document rich margins of adjustment induced by the trade reform at the regional and individual level. Workers initially employed in harder hit regions face continuously deteriorating formal labor market outcomes relative to workers employed in less affected regions, and this gap persists even 20 years after the beginning of trade liberalization. Negative local trade shocks induce workers to shift out of the formal tradable sector and into the formal nontradable sector. Non-employment strongly increases in harder-hit regions in the medium run, but in the longer run, non-employed workers eventually find re-employment in the informal sector. Working age population does not react to these local shocks, but formal sector net migration does, consistent with the relative decline of the formal sector and growth of the informal sector in adversely affected regions

Globalization and inequality in Latin America

We survey the recent literature studying the effects of globalization on inequality in Latin America. Our focus is on research emerging from the late 2000s onward, with an emphasis on empirical work considering new mechanisms, studying new dimensions of inequality, and developing new methodologies to capture the many facets of globalization’s relationship to inequality. After summarizing both design-based and quantitative work in this area, we propose directions for future work. Our overarching recommendation is that researchers develop unifying frameworks to help synthesize the results of individual studies that focus on distinct aspects of globalization’s relationship to inequality

Exploring Bluetooth based Mobile Phone Interaction with the Hermes Photo Display

One of the most promising possibilities for supporting user interaction with public displays is the use of personal mobile phones. Furthermore, by utilising Bluetooth users should have the capability to interact with displays without incurring personal financial connectivity costs. However, despite the relative maturity of Bluetooth as a standard and its widespread adoption in today’s mobile phones, little exploration seems to have taken place in this area - despite its apparent significant potential. This paper describe the findings of an exploratory study nvolving our Hermes Photo Display which has been extended to enable users with a suitable phone to both send and receive pictures over Bluetooth. We present both the technical challenges of working with Bluetooth and, through our user study, we present initial insights into general user acceptability issues and the potential for such a display to facilitate notions of community

Current and Future Critical Issues in Rocket Propulsion Systems

The objective of this research was to tackle several problems that are currently of great importance to NASA. In a liquid rocket engine several complex processes take place that are not thoroughly understood. Droplet evaporation, turbulence, finite rate chemistry, instability, and injection/atomization phenomena are some of the critical issues being encountered in a liquid rocket engine environment. Pulse Detonation Engines (PDE) performance, combustion chamber instability analysis, 60K motor flowfield pattern from hydrocarbon fuel combustion, and 3D flowfield analysis for the Combined Cycle engine were of special interest to NASA. During the summer of 1997, we made an attempt to generate computational results for all of the above problems and shed some light on understanding some of the complex physical phenomena. For this purpose, the Liquid Thrust Chamber Performance (LTCP) code, mainly designed for liquid rocket engine applications, was utilized. The following test cases were considered: (1) Characterization of a detonation wave in a Pulse Detonation Tube; (2) 60K Motor wall temperature studies; (3) Propagation of a pressure pulse in a combustion chamber (under single and two-phase flow conditions); (4) Transonic region flowfield analysis affected by viscous effects; (5) Exploring the viscous differences between a smooth and a corrugated wall; and (6) 3D thrust chamber flowfield analysis of the Combined Cycle engine. It was shown that the LTCP-2D and LTCP-3D codes are capable of solving complex and stiff conservation equations for gaseous and droplet phases in a very robust and efficient manner. These codes can be run on a workstation and personal computers (PC's)

Fault and magmatic interaction within Iceland's western rift over the last 9kyr

We present high-resolution 'Chirp' sub-bottom profiler data from Thingvallavatn, a lake in Iceland's western rift zone. These data are combined with stratigraphic constraints from sediment cores to show that movement on normal faults since 9 ka are temporally correlated with magmatic events, indicating that movements were controlled by episodic dyke intrusion. Sediment depo-centres and the focus of subsidence migrated westwards over 3-4 kyr towards the locus of subsequent brittle failure. We interpret this subsidence as related to dyke intrusion a few km along strike, originating from the Hengill volcanic system, which occurred prior to major dyking, faulting and subsidence within the lake at 1.9 ka

The use of high resolution geophysics for the investigation of submerged palaeo-glaciomarine environments

A multi-disciplinary, high resolution, geophysical investigation of a Scottish Sea loch has facilitated both the reconstruction of a detailed late Quaternary para-stratigraphic model and the critical assessment of the acquisition and analytical methodologies most appropriate for the study of submerged palaeo-glaciomarine environments. Loch Ainort, situated on the eastern coast of the Isle of Skye, has been surveyed using a 192 kHz echosounder, a 400 kHz side scan sonar and a 3.5 kHz sub-bottom profiler. Lithological calibration was provided by the analysis of both in situ core data and extant terrestrial data sets. It is proposed that for the effective reconstruction of these and any other nearshore palaeo-environments a multi-disciplinary geophysical approach is essential. The critical control on success is the adherence, during interpretation, to a single unifying seismo-analytical framework. The seismo-stratigraphical analysis technique has been adapted for high- resolution work in order to provide this rigid framework. Objective descriptive analysis of the seismic traces provides a "seismic para-stratigraphy" which when combined with lithological data is used to construct a "composite para-stratigraphy". This is a process based, litho-stratigraphic interpretation that, by virtue of the detailed spatial extent afforded it by geophysical data, can be placed in a wider environmental context. The composite para-stratigraphy for the Loch Ainort basin is dominated by Loch Lomond Stadial glacial activity. Terminal and readvance limits are identified at several localities within the basin. Variable morphological styles of the glacial sequences show that deglaciation occurred in two distinct, climatically controlled, phases. The first marked by a fluctuating ice margin and the second by uninterrupted retreat and in situ ice stagnation. Sub-aerially induced debris flows occur during the initial paraglacial phase but stabilisation of exposed slopes restricts this input and rapid sedimentation of fines from sediment-rich meltwaters becomes dominant. Modern fjordic sedimentation develops after the disappearance of glacier ice

Trade and Domestic Distortions: The Case of Informality

We examine the effects of international trade in the presence of a set of domestic distortions giving rise to informality, a prevalent phenomenon in developing countries. In our quantitative model, the informal sector arises from burdensome taxes and regulations that are imperfectly enforced by the government. Consequently, smaller, less productive firms face fewer distortions than larger, more productive ones, potentially leading to substantial misallocation. We show that in settings with a large informal sector, the gains from trade are significantly amplified, as reductions in trade barriers imply a reallocation of resources from initially less distorted to more distorted firms. We confirm findings from earlier reduced-form studies that the informal sector mitigates the impact of negative labor demand shocks on unemployment. Nonetheless, the informal sector can exacerbate the adverse welfare effects of economic downturns, amplifying misallocation. Last, our research sheds light on the relationship between trade openness and cross-firm wage inequality

The Production of Chloropicrin as Needed from Dry Mixtures of Picric Acid and Bleaching Powder

Chloropicrin or trichloromethane is a colorless liquid boiling at l 12°C and having a specific gravity of 1.69. It was first prepared by Stenhouse from picric acid and bleaching powder. Its first use was in chemical warfare by the Allied troops in 1918. It was prepared in large quantities at Edgewood Arsenal during the World War, by the method developed and patented by the senior author. Picric acid, hydrated lime, and water were mixed to form a calcium picrate suspension. This suspension together with a suspension of bleaching powder and water was run into a still. The chloropicrin was steam-distilled off