Problems of containment and the promise of planning

Book ChapterWhen the expansion of cities is constrained either by natural barriers, such as New Orleans, or by policy efforts to limit urban sprawl, development pressures in hazardous areas can markedly increase. As floodplains, steep slopes, earthquake fault zones, and other hazardous locations are converted to urban uses, the locality's vulnerability to hazard events increases as does the potential for serious losses of lives and property in natural disasters. The devastation of New Orleans from Hurricane Katrina is an extreme example of the phenomenon. But this threat can be neutralized if hazards are recognized in advance of exposure and appropriate counter-measures are adopted. The difficulty is that in the absence of state planning and hazard mitigation requirements, many localities ignore hazards in planning for and regulating urban development, as shown most recently by Steinberg and Burby (2002). New Orleans and Miami, Florida, provide excellent examples to evaluate the effects of adequate planning and preparation for cities in hazardous areas. New Orleans provides an example of what can occur in a city with severe constraints on buildable land and a lack of adequate public concern for hazards or urban development planning. In contrast, decisions made by policy makers in the State of Florida and by the Miami-Dade County Government illustrate how concern for hazard avoidance and resource protection can lead to policies that sharply limit development in flood-prone areas. To see if lessons revealed by these two cases could be replicated nationwide, we examine natural disasters and associated property damages in samples of metropolitan counties with varying degrees of containment brought about by policy decisions or natural conditions and with varying degrees of planning. And our findings are extremely telling. Metropolitan counties with either natural or policy containment experienced higher property losses in disasters when states left planning and development decisions wholly to local government discretion. Where states intervened and demanded that localities plan and manage development with hazard mitigation in mind, property losses are strikingly lower

The off-axis channel macroplate

High-gain microchannel plates (MCPs) which utilize curvature of the channel to inhibit ion feedback (C-plate MCRs) have demonstrated excellent performance characteristics. However, C-plate MCPs are at present costly to fabricate, and the shearing process used to curve the channels produces a low device yield. Described here is a totally new type of high-gain MCP structure in which each channel has an axially symmetric curvature. Initial tests of proof-of-concept units of these MCPs with 75-micron-diameter channels (macroplates) suggest that their performance characteristics have the potential to be equal to those of a C-plate MCP while the fabrication process is no more complex than that of a conventional straight-channel MCP

Automatic estimation of flux distributions of astrophysical source populations

In astrophysics a common goal is to infer the flux distribution of populations of scientifically interesting objects such as pulsars or supernovae. In practice, inference for the flux distribution is often conducted using the cumulative distribution of the number of sources detected at a given sensitivity. The resulting "$\log(N>S)$-$\log (S)$" relationship can be used to compare and evaluate theoretical models for source populations and their evolution. Under restrictive assumptions the relationship should be linear. In practice, however, when simple theoretical models fail, it is common for astrophysicists to use prespecified piecewise linear models. This paper proposes a methodology for estimating both the number and locations of "breakpoints" in astrophysical source populations that extends beyond existing work in this field. An important component of the proposed methodology is a new interwoven EM algorithm that computes parameter estimates. It is shown that in simple settings such estimates are asymptotically consistent despite the complex nature of the parameter space. Through simulation studies it is demonstrated that the proposed methodology is capable of accurately detecting structural breaks in a variety of parameter configurations. This paper concludes with an application of our methodology to the Chandra Deep Field North (CDFN) data set.Comment: Published in at http://dx.doi.org/10.1214/14-AOAS750 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

Analysis of some compliance calibration data for chevron-notch bar and rod specimens

A set of equations describing certain fracture mechanics parameters for chevron-notch bar and rod specimens are presented. They are developed by fitting earlier compliance calibration data. The difficulty in determining the minimum stress intensity coefficient and the critical crack length is discussed

Genetic Differentiation of Lymphoblastic Sarcoma Histocompatibility Sites in DBA/1J and C57BL/6 Mice

Author Institution: Department of Biological Sciences, Kent State UniversityA chemically induced, 20-methylcholanthrene, lymphoblastic sarcoma, in DBA/1J mice was used to determine the histocompatibility of the tumor between the DBA/1J and C57BL/GJ strains. Although 8 different histocompatibility sites exist between the 2 strains, this work demonstrated that these 8 sites were transmitted and expressed as a 5 unit discrete factor phenotypic variation. Fi x Fi hybrid animals were tested through the Fg generation and showed that only 5 linkage groups are involved in the transmission of the various histocompatibility sites. Survivors of the implanted F9 generation were used as progenitors for the Fi0 generation. Tumor take frequencies with the Fi0 generation demonstrated that the inheritance of tumor susceptibility behaved as a discrete function of a 5 unit inheritance factor