An evaluation tool for design quality: PFI sheltered housing

The complex procurement process entailed by the private finance initiative (PFI) means that clients need new capacities to manage their relationships with bidders and to assess project proposals if the desired level of design quality is to be achieved. To assist local authorities in their client role, a new Architectural Design Quality Evaluation Tool was developed. The aim was to improve the quality of design in residential sheltered housing, procured through the PFI. The tool was developed for and applied to a programme that will see the replacement of a local authority's entire sheltered housing stock. The tool has two functions: (1) to inform the client's assessment process and assist with the selection of the preferred bidding consortium through a series of stages in the PFI process; and (2) to improve the quality of all the submitted designs through an iterative process. Although several existing mechanisms are available for evaluating the performance attributes of buildings, few also tackle the less tangible amenity attributes, which are vital to the feeling of home. The new tool emphasizes the amenity attributes without neglecting performance

Interactions Between Charged Rods Near Salty Surfaces

Using both theoretical modeling and computer simulations we study a model system for DNA interactions in the vicinity of charged membranes. We focus on the polarization of the mobile charges in the membranes due to the nearby charged rods (DNA) and the resulting screening of their fields and inter-rod interactions. We find, both within a Debye-Huckel model and in Brownian dynamics simulations, that the confinement of the mobile charges to the surface leads to a qualitative reduction in their ability to screen the charged rods to the degree that the fields and resulting interactions are not finite-ranged as in systems including a bulk salt concentration, but rather decay algebraically and the screening effect is more like an effective increase in the multipole moment of the charged rod

Architectural Design Quality in Local Authority Private Finance Initiative Projects

Since the 1990s, when the Private Finance Initiative was developed as the primary method for delivering major public capital projects, there has been concern about the quality of many of the products. Initially, it was the architectural community that raised doubts, but it has subsequently been joined by user groups. As the contractual period is over 30 years, there are issues such as ongoing maintenance, facilities management and operational factors, that need to be balanced with design quality. This paper will report on a research project being carried out with a metropolitan local authority in England, which is replacing its entire sheltered housing stock in one Private Finance Initiative project. The principal aim of the local authority is that it should receive these buildings as assets, rather than liabilities at the end of the 30 year period. The research work to date has been based on two stages of a three stage selection of the preferred bidder from the original six consortia. The aims of this paper are to review the Private Finance Initiative management processes in relation to architectural design quality at each of the selection stages, including the generation and application of the design assessment criteria, and the role of user groups; and evaluate the outcomes against the objectives of maximising design quality within workable financial models. The methodology is that the researcher is based in the local authority project team, and has therefore been able to use participant observation techniques in the management processes, which include competitive dialogue and user consultation. The design assessment criteria were developed from the academic literature and refined at each selection stage. A comparative analysis of the design assessment criteria with intermediate and final designs, will assist in identifying the status of design quality in the selection of the preferred bidder

Tidal Decay and Stable Roche-Lobe Overflow of Short-Period Gaseous Exoplanets

Many gaseous exoplanets in short-period orbits are on the verge or are in the process of Roche-lobe overflow (RLO). Moreover, orbital stability analysis shows tides can drive many hot Jupiters to spiral inevitably toward their host stars. Thus, the coupled processes of orbital evolution and RLO likely shape the observed distribution of close-in exoplanets and may even be responsible for producing some of the short-period rocky planets. However, the exact outcome for an overflowing planet depends on its internal response to mass loss, and the accompanying orbital evolution can act to enhance or inhibit RLO. In this study, we apply the fully-featured and robust Modules for Experiments in Stellar Astrophysics (MESA) suite to model RLO of short-period gaseous planets. We show that, although the detailed evolution may depend on several properties of the planetary system, it is largely determined by the core mass of the overflowing gas giant. In particular, we find that the orbital expansion that accompanies RLO often stops and reverses at a specific maximum period that depends on the core mass. We suggest that RLO may often strand the remnant of a gas giant near this orbital period, which provides an observational prediction that can corroborate the hypothesis that short-period gas giants undergo RLO. We conduct a preliminary comparison of this prediction to the observed population of small, short-period planets and find some planets in orbits that may be consistent with this picture. To the extent that we can establish some short-period planets are indeed the remnants of gas giants, that population can elucidate the properties of gas giant cores, the properties of which remain largely unconstrained.Comment: Accepted to "Celestial Mechanics and Dynamical Astronomy" special issue on tides. Several changes based on referee comments, including to the title of the paper. Some new analysis of non-conservative (but still stable) mass transfer as well. Article repository and data files linked to here -- http://www.astrojack.com/research

INTRODUCTION

The Montana Academy of Sciences (MAS) was incorporated on the 20th day of March, 1961, as a non-profit, educational organization. The objectives of the Montana Academy of Sciences are to encourage interest and participation in the sciences and to promote public understanding of science and its contribution to society.  The Academy accomplishes its objectives by conducting meetings of those interested in sciences and the education of scientists, by publishing contributions to scientific knowledge, by supporting research, by making awards to recognize accomplishments in science, by administering gifts and contributions to accomplish these aims, by assigning and cooperating with affiliated and other organizations with similar objectives, and by engaging in such other activities as deemed necessary to accomplish its objectives.We held our 2015 Annual Meeting at Montana Tech in Butte, MT. on April 10 and 11.  Over 100 registrants participated, viewing 29 contributed oral presentations and 20 poster presentations over the day and a half meeting.  The abstracts from this meeting are included in this issue of the Intermountain Journal of Sciences for archival and reference purposes.  The Board of Directors of MAS would like to thank the sponsors of our 2015 Annual Meeting:Dr. Bob Wilmouth, President, Rocky Mountain CollegeDr. Doug Coe, Dean, College of Letters, Sciences and Professional Studies, Montana TechDr. Beverly Hartline, Vice Chancellor for Research, Montana TechDr. Renee Reijo Pera, VP for Research, Montana State UniversityDr. Beth Weatherby, Chancellor, University of Montana-WesternDepartment of Biological and Physical Sciences, Montana State University Billing

R-modes in Neutron Stars with Crusts: Turbulent Saturation, Spin-down, and Crust Melting

Rossby waves (r-modes) have been suggested as a means to regulate the spin periods of young or accreting neutron stars, and also to produce observable gravitational wave radiation. R-modes involve primarily transverse, incompressive motions of the star's fluid core. However, neutron stars gain crusts early in their lives: therefore, r-modes also imply shear in the fluid beneath the crust. We examine the criterion for this shear layer to become turbulent, and derive the rate of dissipation in the turbulent regime. Unlike dissipation from a viscous boundary layer, turbulent energy loss is nonlinear in mode energy and can therefore cause the mode to saturate at amplitudes typically much less than unity. This energy loss also reappears as heat below the crust. We study the possibility of crust melting as well as its implications for the spin evolution of low-mass X-ray binaries. Lastly, we identify some universal features of the spin evolution that may have observational consequences.Comment: 12 pages, 4 figures, submitted to Ap

SHIMM as an atmospheric profiler on the Nickel Telescope

Optimal atmospheric conditions are beneficial for detecting exoplanets via high contrast imaging (HCI), as speckles from adaptive optics' (AO's) residuals can make it difficult to identify exoplanets. While AO systems greatly improve our image quality, having access to real-time estimates of atmospheric conditions could also help astronomers use their telescope time more efficiently in the search for exoplanets as well as aid in the data reduction process. The Shack-Hartmann Imaging Motion Monitor (SHIMM) is an atmospheric profiler that utilizes a Shack-Hartmann wavefront sensor to create spot images of a single star in order to reconstruct important atmospheric parameters such as the Fried parameter ($r_0$), $C_n^2$ profile and coherence time. Due to its simplicity, the SHIMM can be directly used on a telescope to get in situ measurements while observing. We present our implementation of the Nickel-SHIMM design for the one meter Nickel Telescope at Lick Observatory. We utilize an HCIPy simulation of turbulence propagating across a telescope aperture to verify the SHIMM data reduction pipeline as we begin on-sky testing. We also used on-sky data from the AO system on the Shane Telescope to further validate our analysis, finding that both our simulation and data reduction pipeline are consistent with previously determined results for the Fried parameter at the Lick Observatory. Finally, we present first light results from commissioning of the Nickel-SHIMM.Comment: Conference Proceedings for 2023 SPIE Optics and Photonics, Techniques and Instrumentation for Detection of Exoplanets X

Charge-Fluctuation-Induced Non-analytic Bending Rigidity

In this Letter, we consider a neutral system of mobile positive and negative charges confined on the surface of curved films. This may be an appropriate model for: i) a highly charged membrane whose counterions are confined to a sheath near its surface; ii) a membrane composed of an equimolar mixture of anionic and cationic surfactants in aqueous solution. We find that the charge fluctuations contribute a non-analytic term to the bending rigidity that varies logarithmically with the radius of curvature. This may lead to spontaneous vesicle formation, which is indeed observed in similar systems.Comment: Revtex, 9 pages, no figures, submitted to PR