Comparison of seismic site response analysis and downhole array recordings for stiff soil sites

textAccurately predicting surface ground motions is critical for many earthquake engineering applications. Equivalent-linear (EQL) site response analysis is a numerical technique used to compute surface ground motions from input motions at bedrock using the site-specific dynamic soil properties. The purpose of this study was to investigate the accuracy of EQL site response analysis for stiff soil sites by comparing computed and observed transfer functions and response spectral amplification. The Kiban Kyoshin network (KiK-net) in Japan is a seismograph network consisting of downhole array sites with strong-motion accelerometers located at the ground surface and at depth. Recorded motions and shear wave velocity profiles are available for most sites. Observed transfer functions and response spectral amplification were computed for 930 individual seismic recordings at 11 stiff soil KiK-net sites. Computed transfer functions and response spectral amplification were calculated from EQL site response analysis by specifying the KiK-net base sensor motion as the input motion. Sites were characterized using the measured shear wave velocity profiles and nonlinear soil properties estimated from empirical models. Computed and observed transfer functions and response spectral amplification were compared at different levels of strain for each site. The average difference between the observed and computed response spectral amplification across the 11 sites were compared at different levels of strain. Overall, there is reasonable agreement between the computed and observed transfer functions and response spectral amplification. There is agreement between the computed and observed site periods, but with over-prediction of the computed response at the observed site periods. Higher modes often computed by the theoretical model were not always observed by the recordings. There is very good agreement between the computed and observed transfer functions and response spectral amplification for periods larger than the site periods. There is less agreement between the computed and observed transfer functions and response spectral amplification for periods less than the site periods. There is mostly over-prediction of the response spectral amplification at these periods, although some under-prediction also occurred. Across all 11 sites the predicted spectral amplification is within +/-20% at shear strains less than 0.01%. At shear strains between approximately 0.01 and 0.03%, the spectral amplification is over-predicted for these sites, in some instances by as little as 5% and in other instances by a factor of 2 or more.Civil, Architectural, and Environmental Engineerin

MultipliCities : the infrastructure of African American literature, 1899-1996

textMultipliCities: The Infrastructure of African American Literature, 1899-1996 explores intersections between black fiction and canonical sociology through two extended case studies focusing on the authors Richard Wright and Paul Beatty. The formation of disciplinary sociology in the early twentieth century had a profound influence on the production and reception of African American literature. Sociologists at the University of Chicago were among the first to teach black fiction and poetry in the academy, and institutionalized a social scientific framework for comprehending black culture. This framework, which assumes that black writing produces racial knowledge about black experience, continues to pressure contemporary African American authors through the demands of the publishing industry today. At the same time, though, African American authors throughout the twentieth century have resisted sociological expectations for their work and responded critically to the social scientific study of the black community more broadly. MultipliCities studies black writers whose fiction is specifically critical of sociological conceptions of black personhood and place. While Richard Wright's best-selling Native Son (1940) has been canonized as a type of sociological fiction, I read against this critical tradition for the ways in which his juvenile delinquent protagonist, Bigger Thomas, evades his production as a social scientific object. I locate further evidence for Wright's revision of sociological knowledge production in his final, posthumously published novel, A Father's Law (1960; 2008), in which the main character is a sociologist and a serial killer who violently deforms the mastery of the social scientific expert. In my second case study, I turn to contemporary novelist Paul Beatty's post-civil rights era novel The White Boy Shuffle (1996), which I read as a mock ethnography in its description of a postindustrial ghetto that exceeds the sociological imagination of the so-called "culture of poverty." Though rap music is often interpreted as evidence of the alleged impoverishment of inner-city black community, in my final chapter I read Beatty's "hip hop novel" as challenging the social scientific expectations for black popular culture that are part of the ongoing legacy of the canonical sociology of race.Englis

An Analysis of the Legal Obstacles to State Pension Reform

Public pension systems are underfunded, straining state budgets. Historically, many states have presumed that they can modify pension benefits only as to newly-hired employees, and that they must leave benefit accruals untouched for current workers. More recently, though, states have begun enacting more fundamental pension reform that modifies future accruals or even reduces cost-of-living allowances for retirees. Nearly all such new reforms have been the subject of one or more lawsuits alleging that the federal and/or state constitution bars the legislature from reducing benefits or accrual patterns. This dissertation examines the legal underpinnings for arguments made against pension reform, and suggests that constitutional doctrine ought to allow pension systems to be reformed in ways that protect past benefit accruals while reorganizing future benefit accruals in a way that is fairer to younger and more mobile workers. That theory is consistent with contract law and constitutional principles. The dissertation then moves to the real challenge, which is how to apply that theory in particular cases, such as contribution increases, cost of living reductions, retirement age increases, or the establishment of a different pension system entirely. In such cases, it is not always immediately obvious what it means to protect past accruals but allow modifications to future accruals. Given that neither state nor federal judges are pension specialists, courts may benefit from a closer examination of a wide variety of pension reforms

Discovery of a lipid synthesising organ in the auditory system of an insect

Weta possess typical Ensifera ears. Each ear comprises three functional parts: two equally sized tympanal membranes, an underlying system of modified tracheal chambers, and the auditory sensory organ, the crista acustica. This organ sits within an enclosed fluid-filled channel–previously presumed to be hemolymph. The role this channel plays in insect hearing is unknown. We discovered that the fluid within the channel is not actually hemolymph, but a medium composed principally of lipid from a new class. Three-dimensional imaging of this lipid channel revealed a previously undescribed tissue structure within the channel, which we refer to as the olivarius organ. Investigations into the function of the olivarius reveal de novo lipid synthesis indicating that it is producing these lipids in situ from acetate. The auditory role of this lipid channel was investigated using Laser Doppler vibrometry of the tympanal membrane, which shows that the displacement of the membrane is significantly increased when the lipid is removed from the auditory system. Neural sensitivity of the system, however, decreased upon removal of the lipid–a surprising result considering that in a typical auditory system both the mechanical and auditory sensitivity are positively correlated. These two results coupled with 3D modelling of the auditory system lead us to hypothesize a model for weta audition, relying strongly on the presence of the lipid channel. This is the first instance of lipids being associated with an auditory system outside of the Odentocete cetaceans, demonstrating convergence for the use of lipids in hearing

Institutional Foundations for Cyber Security: Current Responses and New Challenges

Almost everyone recognizes the salience of cyberspace as a fact of daily life. Given its ubiquity, scale, and scope, cyberspace has become a fundamental feature of the world we live in and has created a new reality for almost everyone in the developed world and increasingly for people in the developing world. This paper seeks to provide an initial baseline, for representing and tracking institutional responses to a rapidly changing international landscape, real as well as virtual. We shall argue that the current institutional landscape managing security issues in the cyber domain has developed in major ways, but that it is still “under construction.” We also expect institutions for cyber security to support and reinforce the contributions of information technology to the development process. We begin with (a) highlights of international institutional theory and an empirical “census” of the institutions-in-place for cyber security, and then turn to (b) key imperatives of information technology-development linkages and the various cyber processes that enhance developmental processes, (c) major institutional responses to cyber threats and cyber crime as well as select international and national policy postures so critical for industrial countries and increasingly for developing states as well, and (d) the salience of new mechanisms designed specifically in response to cyber threats

Kiwi forego vison in the guidance of their nocturnal activities

We propose that the Kiwi visual system has undergone adaptive regression evolution driven by the trade-off between the relatively low rate of gain of visual information that is possible at low light levels, and the metabolic costs of extracting that information