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SUMMARY Modern microseismic monitoring systems can generate extremely large data sets with signals originating from a variety of natural and anthropogenic sources. These data sets may contain multiple signal types that require classification, analysis and interpretation: a considerable task if done manually. Machine learning techniques may be applied to these data sets to expedite and improve such analysis. In this study, we apply an unsupervised technique, the Self-Organizing Map (SOM), to high-volume data recorded by an in-mine microseismic network. This represents a good example of a large seismic data set that contains a wide range of signals, owing to the diversity of source processes occurring within the mine. The signals are quantified by extracting a number of features (temporal and spectral) from the waveforms which are provided as input data for the SOM. We develop and implement a weighted variant of the SOM in which the contributions of various different features to the training of the map are allowed to evolve. The standard and weighted SOMs are applied to the data, and the output maps compared. Both variants are able to separate source types based on the waveform characteristics, allowing for rapid, automatic classification of signals and the ability to find sources with similar waveforms. Fast classification of such signals provides practical benefit by automatically discarding waveforms associated with anthropogenic sources within the mine while seismic signals originating from genuine microseismic events, which constitute a small fraction of all signals, can be prioritized for subsequent processing and analysis. The weighted variant provides an exploratory tool through quantification of the contribution of different features to the clustering process. This helps to optimize the performance of the SOM through the identification of redundant features. Furthermore, those features that are assigned large weights are considered to be more representative of the source generation processes as they contribute more to the cluster separation process. We apply weighted SOMs to data from a mine recorded during two different time periods, corresponding to different stages of the mine development. Changes in feature importance and in the observed distribution of feature values indicate evolving source generation processes and may be used to support investigatory analysis. The weighted SOM therefore represents an effective tool to help manage and investigate large seismic data sets, providing both practical benefit and insight into underlying event mechanisms.

Future cosmic microwave background (CMB) experiments will deploy increasing numbers of superconducting detectors with requirements for increased sensitivity and reduced systematics. We report on the ongoing development of OMT-coupled CMB detectors at Argonne National Laboratory. Key areas of development include bolometers with dual Transition Edge Sensors (TES) for easier lab characterization, a hybrid SiN membrane fabrication process, a chemical vapor deposition (CVD) SiN dielectric process, and a new pixel design for improved compatibility with large scale fabrication. These developments enhance our ability to fabricate large-scale (150 mm diameter wafers) detector arrays with the performance necessary for future CMB experiments.

Ketamine has played a versatile role in medicine due to its wide spectrum of uses in history including use in sedation, catalepsy, somatic analgesia, bronchodilation, and recent trial in complex chronic pain syndromes. There is very little, if any, discussion in the literature of ketamine use in stroke, particularly in improving symptoms of pain after stroke. We present a case of a 40-year-old female with a past medical history of right-sided thalamic ischemic stroke complicated by Central post-stroke pain syndrome (CPSP) presented for refractory severe diffuse pain causing debility and immobility. The patient failed outpatient medical therapy consisting of anxiolytics, serotonin, and norepinephrine reuptake inhibitors. This led to increased opioid use which resulted in dependence and opioid-hyperalgesia. Upon admission, the patient was unable to sit still, with severe, sharp 10/10 pain localized to her left lower extremity. Palliative medicine was consulted for management of refractory central neuropathic pain. Inpatient oral ketamine was initiated, and titrated over the patient's hospital course. During this time, the patient showed marked improvement in GAD-7, PHQ-9, and Short Mcgill pain scores while significantly decreasing opioid requirements. We present this case to demonstrate how oral ketamine usage in centrally mediated neuropathic pain such as in CPSP can lead to pain control, decreased opioid usage, and overall improved quality of life.

The amount of recorded seismic event data is rapidly growing, and manual processing by trained human experts to infer hypocenter, source parameters, and moment tensor solutions is therefore no longer feasible. Automated procedures are required to process data efficiently and include quality-control measures that allow for outlier detection. We present a modular cross-correlation location (CCLoc) algorithm for induced seismicity that uses cross correlations of either raw seismograms or characteristic functions derived from them followed by a reverse migration procedure. The novelty of this approach is the inclusion of cross pairs of P and S arrivals and the inclusion of autocorrelations, both of which add a distance constraint to the hypocenter estimation. The algorithm is modular in the sense that preprocessing can be tailored to specific data or task. Nine months of seismic data from an underground hard-rock tin mine are processed in a fully automated mode using a machine-learning approach for seismic phase arrival detection and using the estimated arrival functions as input for CCLoc. Making use of the average cross-correlation value as a quality constraint, CCLoc can successfully infer source information on 92% of previously manually processed data. The accuracy of automatic processing is demonstrated by comparing hypocenter, source parameter, and moment tensor solutions between the two datasets. The algorithm will potentially aid the analysis of induced or other seismicity and is particularly well suited to use in the case of large numbers of seismic sensors recording many events.

Does fine-tuning convey an illusion of design or design itself? If Lawrence Krauss remains underwhelmed by arguments in favor of design, Stephen Meyer remains underwhelmed by arguments in favor of Krauss.

We present qualitative observations of the recorded rock mass response to hydraulic-fracturing in four case studies from three major caving mines and demonstrate usefulness in the application of advanced seismological methods to describe this response. Three out of the four cases represent a rare opportunity where the seismic response to hydraulic-fracturing was fairly isolated. The activation of structures was readily evidenced using source mechanism analysis. Hydraulic-fracturing applied along the abutment of a cave was shown to be effective in inducing propagation in a highly stressed, stalled section of the cave. The dominant mode of failure in all cases was shear. The amount and type of volumetric change associated with seismicity was dependent on the proximity of the events to mine voids. Seismic activity rates were estimated to be between 10 and 75 times higher during fluid injection than in the time prior to treatment.

Rapid assessment of areas that may experience damage during large seismic events is an important task of seismic monitoring in rockburst-prone mines, particularly in the seconds to hours following the event. Correctly installed sensors of the appropriate type allow instantaneous and accurate measurement at the location of the sensor. However, the ground motion at any point in the mine could be of interest. Traditionally, this assessment at locations away from sensors was estimated using ground motion prediction equations (GMPEs); specially calibrated equations describing the relationship between ground motion, event strength (radiated seismic energy or seismic potency) and distance. However, the uncertainty in these equations is often quite significant due to complexity of the problem, e.g. radiation pattern effects, extended seismic sources, variations in attenuation characteristics, and uncertainty in source parameters. We improve the accuracy of these estimations by combining the measurements at sensors with a GMPE in an approach known as ShakeMap, popular in crustal seismology. This allows for rapid and more accurate estimation of ground motions at any location following a large event. This knowledge can play an important role in planning of potential post-event evacuation operations and damage assessments. The method is demonstrated on examples from an Australian sublevel caving mine.

Microseismic monitoring is routinely used by block and panel caving mines worldwide to track cave shape development. The standard practice is to use the cloud of seismic event locations as a proxy for cave growth below. Careful seismic sensor array planning overcomes problems with event location reliability due to seismicray bending around the unknown cave. However, the aseismic gap – the (unknown) zone between actual cave back and bottom of the seismic event cloud – complicates estimation of cave geometry. More information than simple seismic event locations can be used to infer the cave shape and position. Since seismic events slip according to the stresses acting locally at the source locations, an analysis of source mechanisms yields indications of principal stresses around the cave. These stresses are the result of the virgin stresses perturbed by the cave shape, and this yields information about the cave shape. The apparent seismic wave arrivals under the straightray assumption are retarded when rays bend around the cave. These anomalous travel times are used to create 'spaghetti' – 3D curved lines indicating the likely ray path followed. Analysis of these curved rays in space and time suggests where the cave is and where it is growing. All of this indirect information is now routinely used at Cadia East mine in Australia to estimate the cave shape, helping geotechnical engineers to better manage the cave. A direct verification of the estimated cave shape with an open hole drilled to the cave back in early 2017 provided some validation of these seismic data techniques.

Page Kidney is a relatively rare cause of Acute Renal Failure (ARF) presenting as accelerated and uncontrolled hypertension secondary direct compression of the renal parenchyma by an extrinsic source. This case report describes a 44-year-old male with advanced acute renal failure requiring hemodialysis, hypertension, and initial suspicion for thrombotic thrombocytopenic purpura who developed a case of Page Kidney following retroperitoneal hematoma following a renal biopsy. The patient was medically managed with intravenous nifedipine until blood pressure stabilized after improvement of the hematoma. Usually hematomas are self-resolving, however rarely they can result in the Page phenomenon—extrinsic compression of the affected kidney by the hematoma resulting in a picture that is similar to acute renal failure (ARF). This case highlights the importance of early medical management of blood pressure control after renal compression has been identified.

This concluding chapter examines the changing work environments in the automotive industry after World War II, and traces the evolution of manhood in the postwar years. It argues that, despite incredible reshaping, the workplace problems of automobile workers after World War II remained much the same as existed at the time of the mass-production revolution. In the postwar years, the problems of technology, race, and gender persisted and in some instances even got much worse—postwar improvements in mechanization and automation meant that workers had to match the pace of more sophisticated technology. In addition, industrial unions brought the most dramatic changes in the relations between workers and managers.

This introductory chapter briefly examines the roots and evolution of working-class manhood. It shows how working-class masculine identity had many roots. The relations of social class, gender, race, and ethnicity influenced and shaped male attitudes, values, and behaviors. Most important, boys becoming men, young men, and adult men fashioned and refashioned their manliness in a variety of all-male settings—such as the workplace. The workplace was central to the forming, nurturing, widening, and deepening of this masculine culture. Generally, this working-class masculine culture has surfaced in two distinct forms—a respectable culture and a rough one. Though analytically quite discrete, these two contradictory forms might result from either personal disposition or social position. Yet they sometimes coexisted with, overlapped with, or blended into each other.

This chapter considers how the increase in numbers of African American men at the workplace brought differing and contentious visions of manhood to the automotive factory. White men, who had long dominated the better jobs, divided into two groups: those who strove for the respectability of high-paid union jobs and those who resented others, fearing the loss of their exclusive white privileges. When black men fought for workplace equity, the more conservative whites conducted racial hate strikes to protect traditionally “white” jobs. In reaction, African American workers conducted what might best be labeled “pride strikes” to gain access to better jobs and later to improve the inequitable situation of black women in the automobile factories. These workplace struggles involved robust clashes over differing visions of manhood.

This chapter investigates the auto workers' rough tactic of fighting to redress workplace grievances and to achieve a decent income to provide for their families, which was used throughout the 1930s and into the early 1940s. After the onset of the Great Depression, American workers in the automobile industry and elsewhere had reached the limits of their tolerance and endurance of the horrid conditions of their work lives. The bitter struggle for industrial unionism was a militant and masculine campaign to alleviate the conditions of life and labor in their communities and mass production factories. The struggle to build unions allowed workers to fight so that they could provide for their families.

This chapter shows that, after mass production undermined and assailed their manhood, auto workers attempted to reassert or to reclaim it in numerous ways, some positive and some negative. They relied on shop traditions, some old and some new, to regain control over their working lives. They looked to and worked to build unions that would provide dignity, a structure to resist hated changes, and a family wage to enhance their personal and economic situations. They reveled in the sexual dimension of manhood in their ribald conversations on the shop floor and in the commercialized and sexual venues of the bachelor culture. As the Great Depression arrived and deepened, they would return to industrial unionism to mitigate the worst of the managerial abuses and would build a dense white and male culture at the workplace.

This chapter examines how female workers rearranged and reconfigured the social contours of the automotive workplace during the onset of World War II. The outbreak of the war had resulted in a huge increase in the volume of defense production as well as the departure of male workers to European and Asian battlefields, leading to severe labor shortages in American plants and factories. As the war progressed, the auto and (later) aircraft industries brought more women into positions formerly reserved for men. These new female workers challenged the privileged position and dominance of men on the shop floor and tested the premises of the densely male shop culture.

This chapter looks at how the mass-production work regime and the aggressive supervision of work all devalued and undermined an auto worker's sense of dignity and manhood. The brutal technical system established a highly controlled work environment of monotony and degradation. For skilled workers and those who aspired to such positions, the desired autonomy and control so essential for manly independence no longer existed. For others, the vicious speed-up, the endless fatigue, the absence of concern for health and safety, the abusive foremen and supervisors, and an uncivilized work environment all revealed lack of concern for human and manly dignity. Auto workers responded, individually and collectively, positively and negatively, to reframe and to reclaim a sense of their manhood through their sometimes retrograde shop floor behaviors, their efforts to fight back through union representation, and their general devaluation of women at work and in their local communities.

This chapter examines the industrial spy, who represented the negative case for the auto workers' notions of exemplary manhood, of real union manhood, and of the manhood of the fighter for unionism or the breadwinner of a family. These industrial mercenaries included many individualistic and anti-labor figures—union supporters called them rats, stool pigeons, finks, sluggers, thugs, goons, scabs, and strikebreakers. They were the union movement's negative examples that separated the honorable and respectable manhood of union men from the dishonorable and disreputable spies and thugs. Often violent men from the underside of urban America, these mercenaries of the class war spent several decades battling industrial unionism.

The identification and quantification of faults or other geological discontinuities is an important task in managing seismic hazard in mines. Unstable slip along these faults may lead to seismic events with fatal or major economic consequences. Current approaches for delineating faults that are employed in mines rely on the interpretation of geological mapping. This mapping, however, may be sparse and can miss structures of potential concern. Clustering techniques are often used to associate seismic events to a common source process, but as previously used make no connection to the underlying physical processes. The Expectation Maximisation Algorithm is used in this study to identify probabilistic kernels representing active segments of faults. This soft assignment clustering method describes the kernels according to the seismic source mechanism, location and location uncertainty of the microseismic events. The method is tested on synthetic data and real data from an underground mine with the aim to delineate a previously unknown structure. Results using synthetic data illustrate how the incorporation of the seismic source mechanism improves the association of events to kernels in the case of scattered events with large location uncertainty. Application of the method to the real data indicates that the results can be interpreted at different levels, a smaller number of kernels provides good and robust description of the overall seismic behaviour, while using more kernels can provide insight into local variations in the location and orientation of faults. The resultant kernels have physical meaning in terms of the location and orientation of the structures. This provides geotechnical engineers at mines with improved tools to identify potentially hazardous areas in the mine and therefore manage these risks.

This book charts the complex vagaries of men reinventing manhood in twentieth-century America. Their ideas of masculinity destroyed by principles of mass production, workers created a white-dominated culture that defended its turf against other racial groups and revived a crude, hypersexualized treatment of women that went far beyond the shop floor. At the same time, they recast unionization battles as manly struggles against a system killing their very selves. Drawing on a wealth of archival material, the book recreates a social milieu in detail—the mean labor and stolen pleasures, the battles on the street and in the soul, and a masculinity that not only expressed itself in violence and sexism but also as a wellspring of the fortitude necessary to maintain one's dignity while doing hard work in a hard world. The book examines the evolution of working-class manhood. It shows how working-class masculine identity had many roots. The relations of social class, gender, race, and ethnicity influenced and shaped male attitudes, values, and behaviors. The book states that the workplace was central to the forming, nurturing, widening, and deepening of this masculine culture.

This article uses worker grievances to explore masculine culture on the shop floor of American automobile factories. It begins with a general discussion of late nineteenth-century working-class masculine culture—the rough culture of laborers and the respectable culture of skilled craftsmen. It then postulates a twentieth-century blending of these two male traditions with the rise of the mass production worker. After raising questions about traditional notions of time and work discipline, it suggests that illicit male behavior loosened the tight managerial control of the workplace. Most of the article explores auto worker grievances and discusses the fundamental elements of masculine culture—malingering, horseplay, gambling, fighting, output restriction, and contesting managerial authority.

A narrowband receiver was installed at the SANAE IV base in Antarctica to monitor specific very low frequency (VLF) radio signals from transmitters around the world. VLF waves propagating through the Earth-Ionosphere Waveguide are excellent probes of the varying properties of the lower region of the ionosphere. This paper describes the set-up of the narrowband system and demonstrates its capabilities with data from a set of solar flares on 08 February and 12 February 2010.

A newly developed chemically amplified (CA) i-line positive resist is designed to reflow the resist structures at relatively low temperatures while eliminating thermal crosslinking mechanisms. The resist can reflow to form clear spherical lenses having greater than 90° contact angles. This is demonstrated by thermally reflowing squared resist posts, 50μm and 80μm in size printed in 48μm resist thickness and 10μm posts in 15μm thickness at 120°C. The resulting lenses have smooth surfaces, free of any wrinkling or residual resist corners.

An approximate analytical model is developed for determining the stresses, strains, and stress concentration in a buffer strip laminate containing a circular cutout. The method is based on the classical shear-lag stress-displacement relations.

We report about the development of a thick negative photoresist series, AZ (R) EXP 125nXT, and their use in electroplating levels up to 160 μm thickness. The new photoresist series enables coatings of 5-120 μm with acceptable uniformity and edge bead in a single coat step. 200 μm photoresist coating was achieved by a double coating processes. The lithographic performance of the photoresists was evaluated using broad band aligners and steppers. Optimized lithographic parameters to achieve straight and nearly vertical side wall profiles are reported. The photoresists show not only excellent adhesion to copper with no surface treatment and electroplating tolerance in a variety of metal plating solutions, but is also compatible with silicon and gold substrates. The photoresists have been found to be easily stripped with no residues in solvent based stripper solutions.

Adapting chemically amplified (CA) resist technology to thick film applications is demonstrated in this paper over a wide range of thicknesses and types of substrates. Substantial performance differences were observed over copper (Cu) substrates compared to silicon (Si). These differences are attributed to different photo acid generator (PAG) distribution in the resist depth influenced by its structure and the nature of the substrate. Optimized resist formulations were developed to provide acceptable performance on Cu wafers. A family of new chemically amplified thick film resist products is being introduced to the market. This technology offers significant advantages in throughput and performance over conventional novolak / diazonaphthoquinone (DNQ) products at a competitive cost.

The development of tools and methods to help reduce the risk of unplanned shutdowns and power reductions is becoming a high priority objective of utility management. By having the capability to monitor the risk to power generation, management can provide additional guidance to the plant staff during work planning and daily work activities concerning conditions that place the plant at a heightened risk with respect to power generation. The Safety Monitor™ can perform evaluations of plant configurations and schedules to function in a forward looking mode to evaluate and avoid conditions that lead to a high trip/power reduction frequency.Copyright © 2004 by ASME

There are a number of hazard barriers installed in power plants. The removal of hazard barriers from service can currently require substantial plant resources to evaluate. These evaluations are usually performed to assess the impact of an open barrier on a plant’s licensing basis and fire protection program and are deterministic in nature. The risk-informed approach to hazard barrier assessment helps alleviate the constraints and manpower requirements imposed by the deterministic approaches currently used. A two-step approach has been developed for performing a risk-informed hazard barrier assessment. The objectives of the first step “Data Gathering” are to review the previously performed analyses and to perform the plant walkdowns and data collection needed for the study. In the second step “Model Development and Quantification” using the most recent Probabilistic Safety Assessment (PSA) system models and the results of the “Data Gathering” walkdowns, a set of fault tree/event tree models are prepared for each unique scenario or hazard to be evaluated. The overall set of barrier impairment impacts is binned into a smaller number of generic categories for the PSA analysis. The quantification results will enable utility management to manage the risk of taking barriers out of service and to make a determination of which barriers could be candidates for a risk-informed impairment out-of-service limit if desired.Copyright © 2004 by ASME

The demand for ultra thick photoresist formulations is steadily increasing. Many applications such as wafer bumping and MEMS (micro electro-mechanical systems) require films in the range of 50 to 100 μm. In our study we measure the dissolution rates of the exposed resist as a function of re-hydration time and other process conditions. Film thickness, processing conditions and developer type are varied for two commercially available resists, AZ® P4620 and AZ®9260 photoresists. It is found that the hydration status of the film has a defining influence on the dissolution behavior. Films that have had insufficient time to re-hydrate cannot be completely dissolved even at very high doses and long development times. Investigation of the water sorption rates by quartz crystal microbalance experiments yielded a diffusion constant of 0.12 μm/sec, in good agreement with literature data on similar systems. Calculations of the water concentration of thick films show that re-hydration times increase in a strongly non-linear fashion with film thickness, so that re-hydration of the lower layers of thick films can take several hours. Under these conditions, there is insufficient water in the lower part of the resist film to react with the ketene generated by photolysis of the DNQ sensitizer. The IR trace of the indenylidene ketene C=C=O stretch band can be observed directly under normal atmospheric humidity conditions. From the observed kinetics, conditions can be derived for re-hydration from the gas or liquid phases that lead to practical process conditions applicable to ultrathick film processing in the fab.