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Abbotsford, Canada

The University of the Fraser Valley , is a Canadian public university with campuses in Abbotsford, Chilliwack, Mission and Hope, British Columbia. Founded in 1974 as Fraser Valley College, it was a response to the need for expanded vocational training in the communities of the Fraser Valley. In 1988, it became a university college, with degree-granting status. As the University College of the Fraser Valley, it grew rapidly, becoming one of the largest university colleges in Canada.In recognition of the growing needs for higher education within the region and in the province, the provincial government granted full university status on 21 April 2008. Student enrollment is now over 15,000 students annually.In the 2010 The Globe and Mail Canadian University Report, UFV earned the most "A Range" grades of any post-secondary institution in British Columbia, receiving A grades in quality of education, student-faculty interaction, and ease of registration. Wikipedia.

This work is concerned with the possible impact binary encoding of strategies may have on the performance of genetic algorithms popular in agent-based computational economic research. In their recent work, Waltman et al. (J Evol Econ 21(5): 737–756, 2011) consider binary encoding and its possible contribution to a phenomenon referred to as premature convergence; the observation that different individual runs of the genetic algorithm can lead to very different results. While Alkemade et al. (Comput Econ 28(4): 355–370, 2006), (Comput Intell 23(2): 162–175, 2007), (Comput Econ 33(1): 99–101, 2009) argue that premature convergence is caused by insufficient population size, Waltman et al. argue that this phenomenon depends crucially on strategies being encoded in binary form. This conclusion is based on their illustration that premature convergence can be avoided even in simulations with small populations so long as real, rather than binary, encoding of strategies is utilized. Utilizing their methodology, we return to the consideration of the cause of premature convergence. After robustness checks with respect to the length of the binary string used for encoding, the fitness function, and the form of mutation, it is concluded that an alternative specification of mutation may also alleviate the occurrence of premature convergence. It is argued that this alternative form of mutation may be more appropriate in a wider range of problems where real encoding of strategies may not prove sufficient. © 2015, Springer Science+Business Media New York. Source

Tania N.,Smith College | Vanderlei B.,University of the Fraser Valley | Heath J.P.,University of British Columbia | Edelstein-Keshet L.,University of British Columbia
Proceedings of the National Academy of Sciences of the United States of America

The dynamics of resource patches and species that exploit such patches are of interest to ecologists, conservation biologists, modelers, and mathematicians. Here we consider how social interactions can create unique, evolving patterns in space and time. Whereas simple prey taxis (with consumable prey) promotes spatial uniform distributions, here we show that taxis in producer-scrounger groups can lead to pattern formation. We consider two types of foragers: those that search directly ("producers") and those that exploit other foragers to find food ("scroungers" or exploiters). We show that such groups can sustain fluctuating spatiotemporal patterns, akin to "waves of pursuit." Investigating the relative benefits to the individuals, we observed conditions under which either strategy leads to enhanced success, defined as net food consumption. Foragers that search for food directly have an advantage when food patches are localized. Those that seek aggregations of group mates do better when their ability to track group mates exceeds the foragers' food-sensing acuity. When behavioral switching or reproductive success of the strategies is included, the relative abundance of foragers and exploiters is dynamic over time, in contrast with classic models that predict stable frequencies. Our work shows the importance of considering two-way interaction - i.e., how food distribution both influences and is influenced by social foraging and aggregation of predators. Source

Antonishen K.,University of the Fraser Valley
Journal of Bodywork and Movement Therapies

There has not been a uniform method for the practice of Baduanjin, and most published research reports involving this set of traditional Chinese exercise have provided incomplete descriptions of the movements used for those studies. This paper reviews elements of past research methodologies of Baduanjin intervention studies and provides considerations for future research. Ambiguities and inconsistencies in the descriptions of the movements, along with some implications which arise from this are discussed. © 2014 Elsevier Ltd. Source

Hanson M.A.,Simon Fraser University | Lian O.B.,University of the Fraser Valley | Clague J.J.,Simon Fraser University
Quaternary Science Reviews

Glacial Lake Missoula formed when the Purcell Trench lobe of the Cordilleran ice sheet dammed Clark Fork River in Montana during the Fraser Glaciation (marine oxygen isotope stage 2). Over a period of several thousand years, the lake repeatedly filled and drained through its ice dam, and floodwaters coursed across the landscape in eastern Washington. In this paper, we describe the stratigraphy and sedimentology of a significant new section of fine-grained glacial Lake Missoula sediment and compare this section to a similar, previously described sequence of sediments at Ninemile Creek, 26km to the northwest. The new exposure, which we informally term the rail line section, is located near Missoula, Montana, and exposes 29units, each of which consists of many silt and clay couplets that we interpret to be varves. The deposits are similar to other fine-grained sediments attributed to glacial Lake Missoula. Similar varved sediments overlie gravelly flood deposits elsewhere in the glacial Lake Missoula basin. Each of the 29units represents a period when the lake was deepening, and all units show evidence for substantial draining of glacial Lake Missoula that repeatedly exposed the lake floor. The evidence includes erosion and deformation of glaciolacustrine sediment that we interpret happened during draining of the lake, desiccation cracks that formed during exposure of the lake bottom, and fluvial sand deposited as the lake began to refill.The floods date to between approximately 21.4 and 13.4cal ka ago based on regional chronological data. The total number of varves at the rail line and Ninemile sites are, respectively, 732 and 583. Depending on lake refilling times, each exposure probably records 1350-1500 years of time. We present three new optical ages from the rail line and Ninemile sites that further limit the age of the floods. These ages, in calendar years, are 15.1±0.6 ka at the base of the Ninemile exposure, and 14.8±0.7 and 12.6±0.6 ka midway through the rail line exposure. The sediment at the two sections was deposited during later stages of glacial Lake Missoula, after the largest outburst events. © 2011 Elsevier Ltd. Source

Brotto L.A.,University of British Columbia | Seal B.N.,University of the Fraser Valley | Rellini A.,University of Vermont
Journal of Sex and Marital Therapy

Although sexual difficulties related to a history of childhood sexual abuse (CSA) are common, there are no efficacious treatments to address sexual distress. Recent evidence for the benefits of mindfulness, which emphasizes present-moment non-judgmental awareness, in the treatment of women's sexual concerns provided the impetus for this pilot study. Twenty partnered women with sexual difficulties and significant sexual distress, and a history of CSA were randomized to two sessions of either a cognitive behavioral (CBT, n = 8) or mindfulness-based (MBT, n = 12) group treatment (age: M = 35.8 years, range: 22-54 years). Hierarchical Linear Modeling to assess changes in concordance between laboratory-based subjective and genital sexual arousal revealed a significant effect of MBT on concordance such that women in the MBT group experienced a significantly greater subjective sexual arousal response to the same level of genital arousal compared to the CBT group and to pre-treatment. Both groups also experienced a significant decrease in sexual distress. These data support the further study of mindfulness-based approaches in the treatment of sexual difficulties characterized by a disconnection between genital and subjective sexual response. Copyright © 2012 Taylor and Francis Group, LLC. Source

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