Trajectory similarity analysis in movement parameter space

This paper introduces a similarity analysis method for moving object trajectories. The proposed method assesses the similarity between a set of trajectories in a multidimensional space, whose dimensions are formed by different movement parameters (e.g. position, speed, acceleration, direction), plus time. We investigate the applicability of the proposed method in finding relative movement patterns such as coincidence and concurrence in the movement of North Atlantic hurricanes

The acceptability of promotional policies to teachers and administrators in five selected communities.

Thesis (Ed.M.)--Boston Universit

Frailty and the Burden of Concurrent and Incident Disability in Patients With Cirrhosis: A Prospective Cohort Study.

Frailty results from the chronic effects of malnutrition and muscle wasting in patients with cirrhosis. It is well-established that frailty is strongly associated with mortality in this population. However, little is known of its relationship with physical disability, a critical patient-centered outcome. Adults with cirrhosis underwent outpatient testing of frailty using the Liver Frailty Index (LFI) and disability using activities of daily living (ADL; range 0-6) and Instrumental ADL (IADL; range 0-8) scales at one center between 2012 and 2016. We used adjusted multilevel logistic mixed-effects regression to test the association between frailty and current disability (impairment with ≥1 ADL or IADL) and incident disability at 6 months among those without baseline disability. Of the 983 participants, 20% were robust, 32% were less robust, 33% were prefrail, and 15% were frail; 587 (60%) had at least 1 assessment. The percentage of participants with at least 1 baseline ADL or IADL impairment was 28% and 37%, respectively. In adjusted regression models, each point LFI increase was associated with a 3.3 and 4.6 higher odds of current difficulty with at least 1 ADL and IADL (P < 0.001 for each), respectively. Among participants without baseline disability, each point LFI increase was associated with a 2.6 and 1.7 higher odds of having difficulty with at least 1 ADL and IADL at 6 months, respectively. Conclusion: Frailty is strongly associated with concurrent and incident disability in patients with cirrhosis. In the clinic, the LFI can be used to identify those in greatest need for additional support/resources to maintain functional independence. In research settings, the LFI may help to identify an enriched population for clinical trials of interventions aimed at those most vulnerable to disability

Exploring movement – similarity analysis of moving objects

Extracting knowledge about the movement of different types of mobile agents (e.g. human, animals, vehicles) and dynamic phenomena (e.g. hurricanes) requires new exploratory data analysis methods for massive movement datasets. Different types of moving objects share similarities but also express differences in terms of their dynamic behavior and the nature of their movement. Extracting such similarities can significantly contribute to the prediction, modeling and simulation dynamic phenomena. Therefore, with the development of a quantitative methodology this research intends to investigate and explore similarities in the dynamics of moving objects by using methods of GIScience in knowledge discovery. This paper presents a summary of the ongoing Ph.D. research project

Skeletal Architecture and Density Banding Analysis Technique for Diploria strigosa by X-ray Computed Tomography

Coral skeletal density information is a useful growth parameter and may be coupled with extension rates to determine calcification rates. The conventional process for density determination is often cumbersome and requires some parameters which are difficult to precisely specify (e.g., Mass absorption coefficients). We have developed a technique and windows based computer program which enables the rapid collection of coral density data. The coral skeleton slab is xradiographed with an aluminum wedge. Thickness and density of the aluminum wedge, thickness of the coral slab, density of pure coral aragonite, and digitized images of the coral and wedge x-radiographs provide necessary input. The program uses the wedge image and an empirically determined ratio of relative mass absorption coefficients, (thus removing difficulties with absolute values) in an equation relating wedge optic density and thickness to coral skeletal density. A transect is defined on the coral x-radiograph image, normal to growth band boundaries. Optic density of pixels are converted to skeletal density, averaged, and plotted. Variations of skeletal density along the transect are expressed as peaks and valleys corresponding to high and low density band portions. Measurements of extension, density, and calcification can be calculated for a variety of characterizations of annual and subannual band portions

Decline of Coral Growth Rates at Negril, Jamaica

Montastrea annularis heads were collected near Negril, Jamaica, along transects from open, normal reef conditions into the mouths of rivers draining the Negril Morass. Corals subject to turbidity (particulate peat and dissolved humic compouonds near rivers, re-suspended reef sediments away from them) were growing more slowly than those in normal circumstances. Surprisingly, corals growing fastest were slowing the most, and the slowest growers increasing growth rate. Linear regression analysis of growth trends over the past two decades revealed stable limit-cycle behavior: change of growth was inversely proportional to growth rate, with a very significant correlation coefficient of -0.92. We suggest that coral growth at Negril is negatively affected by turbidity in freshwater, but locally stimulated by nutrients near the source. Nutrients are likely to be rapidly stripped by dense mats of macrophytic algae which are over-growing corals nearest river mouths

CoralXDS - Coral X-radiograph Densitometry System

The Coral X-radiograph Densitometry System (CoralXDS) is a Windows-based program which provides a tool for measurement of linear extension, density, and calcification from coral X-radiographs. These quantities are determined for high-density, low-density, and annual bands. CoralXDS operates in two modes : full mode and extension/luminance mode. Full mode measures linear extension, density, and calcification, while extension/luminance mode measures only linear extension. Extension/luminance mode requires only a coral image with scaling information. CoralXDS allows user specification of transect location and orientation on the coral image, and provides several options for automated and manual band selection. The output measurements are provided as plots and datasets

The challenge of defining wellbeing

Wellbeing is a growing area of research, yet the question of how it should be defined remains unanswered. This multi-disciplinary review explores past attempts to define wellbeing and provides an overview of the main theoretical perspectives, from the work of Aristotle to the present day. The article argues that many attempts at expressing its nature have focused purely on dimensions of wellbeing, rather than on definition. Among these theoretical perspectives, we highlight the pertinence of dynamic equilibrium theory of wellbeing (Headey & Wearing, 1989), the effect of life challenges on homeostasis (Cummins, 2010) and the lifespan model of development (Hendry & Kloep, 2002). Consequently, we conclude that it would be appropriate for a new definition of wellbeing to centre on a state of equilibrium or balance that can be affected by life events or challenges. The article closes by proposing this new definition, which we believe to be simple, universal in application, optimistic and a basis for measurement. This definition conveys the multi-faceted nature of wellbeing and can help individuals and policy makers move forward in their understanding of this popular term

Ammonia Leak Locator Study

The thermal control system of International Space Station Alpha will use liquid ammonia as the heat exchange fluid. It is expected that small leaks (of the order perhaps of one pound of ammonia per day) may develop in the lines transporting the ammonia to the various facilities as well as in the heat exchange equipment. Such leaks must be detected and located before the supply of ammonia becomes critically low. For that reason, NASA-JSC has a program underway to evaluate instruments that can detect and locate ultra-small concentrations of ammonia in a high vacuum environment. To be useful, the instrument must be portable and small enough that an astronaut can easily handle it during extravehicular activity. An additional complication in the design of the instrument is that the environment immediately surrounding ISSA will contain small concentrations of many other gases from venting of onboard experiments as well as from other kinds of leaks. These other vapors include water, cabin air, CO2, CO, argon, N2, and ethylene glycol. Altogether, this local environment might have a pressure of the order of 10(exp -7) to 10(exp -6) torr. Southwest Research Institute (SwRI) was contracted by NASA-JSC to provide support to NASA-JSC and its prime contractors in evaluating ammonia-location instruments and to make a preliminary trade study of the advantages and limitations of potential instruments. The present effort builds upon an earlier SwRI study to evaluate ammonia leak detection instruments [Jolly and Deffenbaugh]. The objectives of the present effort include: (1) Estimate the characteristics of representative ammonia leaks; (2) Evaluate the baseline instrument in the light of the estimated ammonia leak characteristics; (3) Propose alternative instrument concepts; and (4) Conduct a trade study of the proposed alternative concepts and recommend promising instruments. The baseline leak-location instrument selected by NASA-JSC was an ion gauge