Determination of bone mineral mass in vivo

Radiographic equipment incorporates two radiation sources, generating high-energy and low-energy beams. Recording equipment measures amount of radiation that has penetrated limb. Data are fed into computer that determines mass of the examined bone

Expected Utility in Models with Chaos

In this paper, we provide a framework for calculating expected utility in models with chaotic equilibria and consequently a framework for ranking chaos. Suppose that a dynamic economic model’s equilibria correspond to orbits generated by a chaotic dynamical system f : X ! X where X is a compact metric space and f is continuous. The map f could represent the forward dynamics xt+1 = f(xt) or the backward dynamics xt = f(xt+1). If f represents the forward/backward dynamics, the set of equilibria forms a direct/inverse limit space. We use a natural f-invariant measure on X to induce a measure on the direct/inverse limit space and show that this induced measure is a natural ¾-invariant measure where ¾ is the shift operator. We utilize this framework in the cash-in-advance model of money where f is the backward map to calculate expected utility when equilibria are chaotic.chaos, inverse limits, direct limits, natural invariant measure, cash-in-advance

Estimating water flow through a hillslope using the massively parallel processor

A new two-dimensional model of water flow in a hillslope has been implemented on the Massively Parallel Processor at the Goddard Space Flight Center. Flow in the soil both in the saturated and unsaturated zones, evaporation and overland flow are all modelled, and the rainfall rates are allowed to vary spatially. Previous models of this type had always been very limited computationally. This model takes less than a minute to model all the components of the hillslope water flow for a day. The model can now be used in sensitivity studies to specify which measurements should be taken and how accurate they should be to describe such flows for environmental studies

Meeting the Needs of Diverse Students: Enhancing School Counselors’ Experience

The National Council for Accreditation of Teacher Education (NCATE) is the premier teacher education program accreditation body. In addition to reviewing teacher preparation programs in institutions of higher learning, NCATE also reviews school administration programs and other school specialist programs, including school counseling programs

"So, Tell Me What Users Want, What They Really, Really Want!"

Equating users' true needs and desires with behavioural measures of 'engagement' is problematic. However, good metrics of 'true preferences' are difficult to define, as cognitive biases make people's preferences change with context and exhibit inconsistencies over time. Yet, HCI research often glosses over the philosophical and theoretical depth of what it means to infer what users really want. In this paper, we present an alternative yet very real discussion of this issue, via a fictive dialogue between senior executives in a tech company aimed at helping people live the life they `really' want to live. How will the designers settle on a metric for their product to optimise

Fabrication of thin film composite poly(amide)-carbon-nanotube supported membranes for enhanced performance in osmotically driven desalination systems

The search for lower energy consumption desalination systems has been driving research in the past decade towards the investigation of osmotically driven membrane processes, such as forward osmosis (FO) or osmotic distillation (OD). Despite similarities with reverse osmosis (RO) membranes, thin film composite (TFC) for FO membranes require careful design to reduce salt concentration polarization formation within the large pores composing the supporting layer. An investigation of a novel, highly stable, robust support made solely of carbon nanotubes (CNTs), which could find applications in both RO and FO was undertaken. TFC membranes were fabricated by interfacially polymerizing for the first time a dense poly(amide) (PA) layer on self-supporting bucky-papers (BPs) made of hydroxyl-functionalized entangled CNTs. These hydrophilic supports exhibited low contact angle with water (90%), making it a promising material when compared with poly(sulfone) (PSf), the traditional polymer used to fabricate TFC membrane supports in RO. In addition, the impact of the support hydrophilicity on the stability of the interfacially polymerized film and on water adsorption was investigated by oxygen-plasma treating various potential support materials, exhibiting similar geometrical properties. The morphology and salt diffusion of both CNT BP and PSf supports were investigated, and the novel BP–PA composite membranes were found to be superior to commercially available TFC membranes

Chautauqua in Devils Lake, North Dakota: An Historical Study of the Organization, the Facilities, and Programs

Chautauqua, a totally American institution which impacted nearly forty million people in its approximately fifty-year existence from 1874 to 1930, was a place to enrich lives through education, inspiration, and recreation. Devils Lake, North Dakota, a small, isolated town on the Midwestern plains, located on the shores of a large, salt-water lake, became the site of the nation\u27s third largest independent Chautauqua in the nation, operating from 1893 to 1929. This thesis is a study of the history of the Devils Lake Chautauqua, its organization, and development. Included in the research is a study of the national Chautauqua and Lyceum Movements, how those movements became intertwined, and how the two movements impacted the Chautauqua in Devils Lake. The history of the Chautauqua includes a discussion of the facilities and activities at the Devils Lake site, includ ing the Chautauqua Railroad and Captain S. E. Heerman and his steamship, the Minnie H, two activities that made the Devils Lake Chautauqua unique. An analysis of the programming, the themes and quality, is also provided. The demise of the Devils Lake Chautauqua and the subsequent revival in 1976 are also discussed. Two tables list and categorize the programs by type: religious, political, educational/inspirational, musical, elocution and drama, and other miscellaneous types. One of the two tables covers the first five years of programming; the second covers the last four years for which complete programming information is available. Maps of the Chautauqua grounds are included, as is a copy of the speech given by William Jennings Bryan on July 6, 1918, the most famous speaker ever booked at the Devils Lake Chautauqua. Two typical stories used by teachers at the Kindergarten are also provided, as well as several illustrations of the facilities and typical activities

Interdependent Pricing and Markup Behavior: An Empirical Analysis of GM, Ford and Chrysler

Our purpose in this paper is to develop and estimate a model of the US automobile industry that can be used to analyze the secular and cyclical strategic markup behavior and market structure of its three major domestic producers - - GM, Ford and Chrysler. The principal novelty in this paper is not such much in the underlying theory (we build on what Timothy Bresnahan has called the "new empirical industrial organization" literature), but rather in the actual empirical implementation of a multi-equation model sufficiently general to permit the testing of a variety of specific behavioral postulates associated with the interdependent strategic profit-maximizing behavior of GM, Ford and Chrysler. Using firm-specific annual data from 1959-83, we find that at usual levels of statistical significance, we cannot reject Cournot quantity-setting behavior, nor can we reject leader/follower quantity-setting behavior with GM as leader and Ford and Chrysler as followers; the parameter restrictions associated with leader/follower behavior are slightly more binding than those with Cournot, although the difference is not decisive. In terms of the cyclical analysis of market behavior, our most striking result is the great diversity of behavior we find among GM, Ford and Chrysler. Depending on which firm is being analyzed, there is support for the pro-cyclical "conventional wisdom" of markups (GM and Ford), as well as for the counter-cyclical "revisionist" literature (Chrysler). Diversity, rather than constancy and homogeneity, best characterizes firms in this industry.