894 research outputs found
Pattern languages in HCI: A critical review
This article presents a critical review of patterns and pattern languages in human-computer interaction (HCI). In recent years, patterns and pattern languages have received considerable attention in HCI for their potential as a means for developing and communicating information and knowledge to support good design. This review examines the background to patterns and pattern languages in HCI, and seeks to locate pattern languages in relation to other approaches to interaction design. The review explores four key issues: What is a pattern? What is a pattern language? How are patterns and pattern languages used? and How are values reflected in the pattern-based approach to design? Following on from the review, a future research agenda is proposed for patterns and pattern languages in HCI
Water Quality Impacts of Naturals Riparian Grasses Part 2: Modeling Effects of Channelization on Sediment Trapping
A methodology is developed to determine expected sediment trapping in riparian vegetative filter strips considering channelization of flow. The framework consists of defining the channel network stochastically, with deposition/detachment in each channel being modeled deterministically. The two approaches were then combined to develop a model which could predict expected trapping efficiencies for vegetative filters under known field conditions. The model was then extended to include conditions such as rainfall on the filter so as to make it applicable to generic field situations.
Field and laboratory studies were conducted to collect and estimate data to develop and evaluate the model. sediment concentrations were measured for natural vegetative filters located on a slope of 8.7%, subjected to inflows from upslope bare soil plots. Surface elevations were measured for the filter. Flow networks and channel shapes were defined by applying the digital elevation model to the micro-relief data. Actual distributions and standard fitted distributions for channel flows and channel shapes were developed.
Model evaluation was done for selected values of Manning\u27s n to give predicted filter trapping efficiencies within 2% of the observed, indicating model validity. Sensitivity analysis was conducted using the general model and the fitted probability distributions
Resources, mortality, and disease ecology: Importance of positive feedbacks between host growth rate and pathogen dynamics
This is an Accepted Manuscript of an article published by Taylor & Francis in Israel Journal of Ecology and Evolution in 2015, available online: http://www.tandfonline.com/10.1080/15659801.2015.1035508.Resource theory and metabolic scaling theory suggest that the dynamics of a pathogen within a host should strongly depend upon the rate of host cell metabolism. Once an infection occurs, key ecological interactions occur on or within the host organism that determine whether the pathogen dies out, persists as a chronic infection, or grows to densities that lead to host death. We hypothesize that, in general, conditions favoring rapid host growth rates should amplify the replication and proliferation of both fungal and viral pathogens. If a host population experiences an increase in mortality, to persist it must have a higher growth rate, per host, often reflecting greater resource availability per capita. We hypothesize that this could indirectly foster the pathogen, which also benefits from increased within-host resource turnover. We first bring together in a short review a number of key prior studies which illustrate resource effects on viral and fungal pathogen dynamics. We then report new results from a semi-continuous cell culture experiment with SHIV, demonstrating that higher mortality rates indeed can promote viral proliferation. We develop a simple model that illustrates dynamical consequences of these resource effects, including interesting effects such as alternative stable states and oscillatory dynamics. Our paper contributes to a growing body of literature at the interface of ecology and infectious disease epidemiology, emphasizing that host abundances alone do not drive community dynamics: the physiological state and resource content of infected hosts also strongly influence host-pathogen interactions
ESTUDO LONGITUDINAL DE FATORES QUE AFETAM O RISCO DE FRATURA POR ESTRESSE EM DUAS POPULAÇÕES DE COLEGIAIS DO SEXO FEMININO
Objetivos: As fraturas por estresse causam significante morbidade em mulheres. Diferenças no
nĂvel de atividades, valores hormonais e densidade mineral Ăłssea (BMD) afetam diferentemente
as taxas de fraturas por estresse. Os autores hipotetizaram que mulheres de um Colégio militar
terĂŁo maior nĂvel de atividade do que mulheres em colĂ©gios com um ambiente mais flexĂvel, que
correlacionará com mudanças nos valores hormonais, menor (BMD) e mais fraturas por estresse.
Método: Nesse estudo prospectivo comparativo, 63 mulheres de duas Instituições (The Citadel:
The Military College Of South Carolina And The College Of Cherleston) relataram
detalhadamente suas atividades, dieta e lesões através de um questionário e tiveram sua BMB e
os valores hormonais sĂ©ricos medidos num intervalo de 06 meses, por um perĂodo de 2 anos; 38
sujeitos completaram o estudo. A análise estatĂstica examinou diferenças e mudanças ao longo
do tempo entre as duas amostras.Resultados: Uma fratura por estresse ocorreu em cada Instituição. As mulheres do Citadel
tiveram maiores nĂveis de atividade, que as mulheres do College of Charleston no longo do
estudo. As mulheres do Citadel tiveram menor nĂvel de hormĂ´nio folĂculo estimulante, maior
17 Beta-Estradiol aos 24 meses e maior BMD na extremidade proximal femoral aos 18 meses da
investigação (p< 0,05).
Conclusões: Os valores sĂ©ricos hormonais podem ser um indicador mais sensĂvel de resposta ao
nĂvel da atividade fĂsica que o BMD dentro da amostra e duração deste estudo. Outros estudos
são necessários para definir esta complexa interrelação.
LONGITUDINAL STUDY OF FACTORS AFFECTING STRESS FRACTURE RISK IN TWO DISTINCT COLLEGE FEMALE POPULATIONS
Abstract
Objectives: Stress fractures cause significant morbidity in females. Differences in activity
levels, hormone values, and bone mineral density (BMD) affect different rates of stress fracture.
The authors hypothesized that females at a military college will have greater activity levels than
females in a flexible college environment, which will correlate with greater changes in hormone
values, lower BMD, and more stress fractures.
Methods: In this prospective comparative study 63 females from two institutions (The Citadel:
The Military College of South Carolina and the College of Charleston) self-reported on a detailed
activity, diet, and injury questionnaire and had BMD and serum hormone values measured at 6-
month intervals for a two year period; 38 completed the study. Statistical analysis was designed
to examine differences and changes over time between the two samples.
Results: One stress fracture occurred in each institution. Citadel females had higher activity
levels than females at the College of Charleston throughout the study. Citadel females had
lower follicle stimulating hormone levels at 24 months, greater 17 beta-estradiol at 24 months,
and greater proximal femoral BMD at eighteen months (
Sonically-enhanced widgets: comments on Brewster and Clarke, ICAD 1997
This paper presents a review of the research surrounding the paper “The Design and Evaluation of a Sonically Enhanced Tool Palette” by Brewster and Clarke from ICAD 1997. A historical perspective is given followed by a discussion of how this work has fed into current developments in the area
Hydrology and Sedimentology of Dynamic Rill Networks Volume II: Hydrologic Model for Dynamic Rill Networks
A comprehensive model has been developed for use in modeling the hydrologic response of rill network systems. The model, which is called HYMODRIN, is composed of both a hydrologic runoff component and a hydraulic channel routing component. The hydrologic component of the model uses a Green Ampt infiltration approach linked with a nonlinear reservoir runoff model. The channel routing component of the model is baaed on a finite element solution of the diffusion wave equations. In order to account for backwater effects the model employs a dual level iteration scheme.
The model may be used in either a stand alone mode or as part of a comprehensive integrated rill erosion model. In the latter case, the hydrologic data for the rill network and the associated interrill flow areas is provided by a geographic-hydrologic interface model called GHIM. This model accepts data from a digital elevation model and translates it into a form compatible with the hydrologic model.
This report contains the theoretical development and operating instructions for both GHIM and HYMODRIN. Computer listings for both programs are provided
Volatile Decision Dynamics: Experiments, Stochastic Description, Intermittency Control, and Traffic Optimization
The coordinated and efficient distribution of limited resources by individual
decisions is a fundamental, unsolved problem. When individuals compete for road
capacities, time, space, money, goods, etc., they normally make decisions based
on aggregate rather than complete information, such as TV news or stock market
indices. In related experiments, we have observed a volatile decision dynamics
and far-from-optimal payoff distributions. We have also identified ways of
information presentation that can considerably improve the overall performance
of the system. In order to determine optimal strategies of decision guidance by
means of user-specific recommendations, a stochastic behavioural description is
developed. These strategies manage to increase the adaptibility to changing
conditions and to reduce the deviation from the time-dependent user
equilibrium, thereby enhancing the average and individual payoffs. Hence, our
guidance strategies can increase the performance of all users by reducing
overreaction and stabilizing the decision dynamics. These results are highly
significant for predicting decision behaviour, for reaching optimal behavioural
distributions by decision support systems, and for information service
providers. One of the promising fields of application is traffic optimization.Comment: For related work see http://www.helbing.or
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