Opin vísindi

 

Nýlega bætt við

Verk
Sick and tired of being sick and tired! : What to do about fatigue associated with cancer and its treatment.
(2021) Fox, Rina S.; Wu, Lisa Maria; Department of Psychology
Verk
Editorial : Sleep and circadian rhythms in cancer patients and their relationship with quality of life
(2022-11-28) Perrier, Joy; Giffard, Bénédicte; Wu, Lisa M.; Savard, Josée; Amidi, Ali; Department of Psychology
Verk
I Keep my Problems to Myself : Negative Social Network Orientation, Social Resources, and Health-Related Quality of Life in Cancer Survivors
(2016-06-01) Rini, Christine; Symes, Yael; Campo, Rebecca A.; Wu, Lisa M.; Austin, Jane; Department of Psychology
Background: Cancer survivors treated with hematopoietic stem cell transplant rely on their social network for successful recovery. However, some survivors have negative attitudes about using social resources (negative social network orientation) that are critical for their recovery. Purpose: We examined the association between survivors’ social network orientation and health-related quality of life (HRQoL) and whether it was mediated by social resources (network size, perceived support, and negative and positive support-related social exchanges). Methods: In a longitudinal study, 255 survivors completed validated measures of social network orientation, HRQoL, and social resources. Hypotheses were tested using path analysis. Results: More negative social network orientation predicted worse HRQoL (p <.001). This association was partially mediated by lower perceived support and more negative social exchanges. Conclusions: Survivors with negative social network orientation may have poorer HRQoL in part due to deficits in several key social resources. Findings highlight a subgroup at risk for poor transplant outcomes and can guide intervention development.
Verk
Supersonic airfoil shape optimization by variable-fidelity models and manifold mapping
(2016) Siegler, Jacob; Ren, Jie; Leifsson, Leifur; Koziel, Slawomir; Bekasiewicz, Adrian; Department of Engineering
Supersonic vehicles are an important type of potential transports. Analysis of these vehicles requires the use of accurate models, which are also computationally expensive, to capture the highly nonlinear physics. This paper presents results of numerical investigations of using physics-based surrogate models to design supersonic airfoil shapes. Variable-fidelity models are generated using inviscid computational fluid dynamics simulations and analytical models. By using response correction techniques, in particular, the manifold mapping technique, fast surrogate models are constructed. The effectiveness of the approach is investigated using lift-constrained drag minimization problems of supersonic airfoil shapes. Compared with direct optimization, the results show that an order of magnitude speed up can be obtained. Furthermore, we investigate the effectiveness of the variable-fidelity technique in terms of speed and design quality using several combinations of medium-fidelity and low-fidelity models.
Verk
Sequential domain patching for computationally feasible multi-objective optimization of expensive electromagnetic simulation models
(2016) Bekasiewicz, Adrian; Koziel, Slawomir; Leifsson, Leifur; Department of Engineering
In this paper, we discuss a simple and efficient technique for multi-objective design optimization of multi-parameter microwave and antenna structures. Our method exploits a stencil-based approach for identification of the Pareto front that does not rely on population-based metaheuristic algorithms, typically used for this purpose. The optimization procedure is realized in two steps. Initially, the initial Pareto-optimal set representing the best possible trade-offs between conflicting objectives is obtained using low-fidelity representation (coarsely-discretized EM model simulations) of the structure at hand. This is realized by sequential construction and relocation of small design space segments (patches) in order to create a path connecting the extreme Pareto front designs identified beforehand. In the second step, the Pareto set is refined to yield the optimal designs at the level of the high-fidelity electromagnetic (EM) model. The appropriate number of patches is determined automatically. The approach is validated by means of two multi-parameter design examples: a compact impedance transformer, and an ultra-wideband monopole antenna. Superiority of the patching method over the state-of-the-art multi-objective optimization techniques is demonstrated in terms of the computational cost of the design process.

Flokkar í Opnum vísindum

Veldu flokk til að skoða.

Niðurstöður 1 - 9 af 9