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Sample records for antsulevich pentti vlipaikka

  1. A Positive Reply to Constructive Criticism

    ERIC Educational Resources Information Center

    Kilpinen, Erkki

    2005-01-01

    In this essay, Kilpinen responds to Terry Gates, Scott Goble, and Pentti Maattanen, who have provided reviews of his dissertation book "The Enormous Fly-Wheel of Society." As the reviewers noted, the book attempts to make two points simultaneously, and it may be that this made its argument hard to follow. The first point, that thorough knowledge…

  2. A view of Kanerva's sparse distributed memory

    NASA Technical Reports Server (NTRS)

    Denning, P. J.

    1986-01-01

    Pentti Kanerva is working on a new class of computers, which are called pattern computers. Pattern computers may close the gap between capabilities of biological organisms to recognize and act on patterns (visual, auditory, tactile, or olfactory) and capabilities of modern computers. Combinations of numeric, symbolic, and pattern computers may one day be capable of sustaining robots. The overview of the requirements for a pattern computer, a summary of Kanerva's Sparse Distributed Memory (SDM), and examples of tasks this computer can be expected to perform well are given.

  3. Sparse distributed memory

    NASA Technical Reports Server (NTRS)

    Denning, Peter J.

    1989-01-01

    Sparse distributed memory was proposed be Pentti Kanerva as a realizable architecture that could store large patterns and retrieve them based on partial matches with patterns representing current sensory inputs. This memory exhibits behaviors, both in theory and in experiment, that resemble those previously unapproached by machines - e.g., rapid recognition of faces or odors, discovery of new connections between seemingly unrelated ideas, continuation of a sequence of events when given a cue from the middle, knowing that one doesn't know, or getting stuck with an answer on the tip of one's tongue. These behaviors are now within reach of machines that can be incorporated into the computing systems of robots capable of seeing, talking, and manipulating. Kanerva's theory is a break with the Western rationalistic tradition, allowing a new interpretation of learning and cognition that respects biology and the mysteries of individual human beings.

  4. Trajectories of Sleep Complaints From Early Midlife to Old Age: Longitudinal Modeling Study

    PubMed Central

    Salo, Paula; Vahtera, Jussi; Ferrie, Jane E.; Akbaraly, Tasnime; Goldberg, Marcel; Zins, Marie; Pentti, Jaana; Virtanen, Marianna; Shipley, Martin J.; Singh-Manoux, Archana; Dauvilliers, Yves; Kivimaki, Mika

    2012-01-01

    Study Objectives: To estimate trajectories of sleep lost over worry as a function of age, using longitudinal modeling, and compare these trajectories with those for insomnia symptoms. Design and Setting: Data from two prospective, occupational cohorts (the Whitehall II and Finnish Public Sector studies) comprising 84,384 observations from four to eight repeat measurements in 1985-2010. Participants: There were 16,408 men and women age 34-79 yr. Measurements and Results: Age-related trajectories of sleep lost over worry and insomnia symptoms (sleep initiation or maintenance problems, nonrefreshing sleep) were estimated using repeated-measures log-binomial regression analysis and generalized estimating equations. These analyses were adjusted for year of birth and time of measurement to minimize confounding by cohort or period effects. The prevalence ratio for insomnia symptoms was higher in older age groups compared with participants age 34-45 yr. In contrast, the age-related trajectory of sleep lost over worry included two phases: a period of high prevalence of sleep complaints at age 34-60 yr followed by a declining trajectory at older ages. Compared with participants age 34-45 yr, prevalence ratios for sleep lost over worry were 0.63 (0.49-0.80) and 0.59 (0.41-0.84) in the Whitehall II study participants ages 61-65 and 71-79 years. Corresponding figures were 0.62 (0.52-0.75) and 0.46 (0.32-0.66) in the Finnish Public Sector study. Conclusion: This study shows a general age-related decrease in sleep lost over worry between late midlife and old age, a pattern strikingly different from the age-related increase in insomnia symptoms. Citation: Salo P; Vahtera J; Ferrie JE; Akbaraly T; Goldberg M; Zins M; Pentti J; Virtanen M; Shipley MJ; Singh-Manoux A; Dauvilliers Y; Kivimaki M. Trajectories of sleep complaints from early midlife to old age: longitudinal modeling study. SLEEP 2012;35(11):1559-1568. PMID:23115405

  5. Work Time Control and Sleep Disturbances: Prospective Cohort Study of Finnish Public Sector Employees

    PubMed Central

    Salo, Paula; Ala-Mursula, Leena; Rod, Naja Hulvej; Tucker, Philip; Pentti, Jaana; Kivimäki, Mika; Vahtera, Jussi

    2014-01-01

    Objectives: Employee control over work times has been associated with favorable psychosocial and health-related outcomes, but the evidence regarding sleep quality remains inconclusive. We examined cross-sectional and prospective associations between work time control and sleep disturbances in a large working population, taking into account total hours worked. Methods: The data were from a full-panel longitudinal cohort study of Finnish public sector employees who responded to questions on work time control and sleep disturbances in years 2000-2001, 2004-2005, 2008-2009, and 2012. The analysis of cross-sectional associations was based on 129,286 person measurements from 68,089 participants (77% women) aged 17-73 years (mean 43.1). Data from 16,503 participants were used in the longitudinal analysis. Log-binomial regression analysis with the generalized estimating equations method was used. Results: Consistently in both cross-sectional and longitudinal models, less control over work time was associated with greater sleep disturbances in the total population and among those working normal 40-hour weeks. Among participants working more than 40 hours a week, work time that was both very high (cross-sectional prevalence ratio compared to intermediate work time control [PR] 1.32, 95% confidence interval [CI] 1.05-1.65) and very low (PR 1.23, 95% CI 1.08-1.39) was associated with sleep disturbances, after adjustment for potential confounding factors. Conclusions: These data suggest that having few opportunities to influence the duration and positioning of work time may increase the risk of sleep disturbances among employees. For persons working long hours, very high levels of control over working times were also associated with increased risk of sleep disturbances. Citation: Salo P, Ala-Mursula L, Rod NH, Tucker P, Pentti J, Kivimäki M, Vahtera J. Work time control and sleep disturbances: prospective cohort study of Finnish public sector employees. SLEEP 2014