2,773 research outputs found
A Robust Rational Route to in a Simple Asset Pricing Model (revised March 2004)
We investigate asset pricing dynamics in an adaptive evolutionary asset pricing model with fundamentalists, trend followers and a market maker. Agents can choose between a fundamentalist strategy at positive information cost or choose a trend following strategy for free. Price adjustment is proportional to the excess demand in the asset market. Agents asynchronously update their strategy according to realized net profits in the recent past. As agents become more sensitive to differences in strategy performance, the fundamental steady state becomes unstable and multiple steady states may arise. As the traders' sensitivity to differences in fitness increases, a bifurcation route to chaos sets in due to homoclinic bifurcations of stable and unstable manifolds of the fundamental steady state.
Modification of the Charnock Wind Stress Formula to Include the Effects of Free Convection and Swell
DIFFERENCES BETWEEN CONCENTRIC AND ECCENTRIC CONTRACTION INDUCED MUSCLE FATIGUE
Studies of neuromuscular activation often evaluated through isometric contractions. However, this type of contraction may not truly represent muscle actions during activities. EMG analysis is not only used to determine motor unit activations, but also used to determine muscle conduction velocity by transforming signals into frequency spectrum. Studies have shown that fatigue mucles produced a relativly slower conduction velocity measured by mean power frequency (MPF). Therefore, the purpose of this study was to compare the effects of muscle fatigue generated by two different types of contraction. We hypothesized that muscle fatigue generated by concentric contractions (CC) would cause gretaer muscle contraction frequency reduction than eccentric contractions (EC)
Investigation on the sampling size optimisation in gear tooth surface measurement using a Co-ordinate Measuring Machine
Co-ordinate Measuring Machines (CMMs) are widely used in gear manufacturing industry. One of the main issues for contact inspection using a CMM is the sampling technique. In this paper the gear tooth surfaces are expressed by series of parameters and inspection error compensation and initial value optimisation method are presented. The minimum number of measurement points for 3D tooth surfaces are derived. If high precision is required, more points need to be inspected. The sampling size optimisation is obtained from the criterion equation. The surface form deviation and initial values are optimised using the minimum zone method and Genetic Algorithms. A feature based inspection system for spur/helical gears is developed and trials and simulations demonstrated the developed method is very effective and suitable
A Necessary And Sufficient Condition of Distillability with unite fidelity from Finite Copies of a Mixed State: The Most Efficient Purification Protocol
It is well known that any entangled mixed state in systems can
be purified via infinite copies of the mixed state. But can one distill a pure
maximally entangled state from finite copies of a mixed state in any bipartite
system by local operation and classical communication? This is more meaningful
in practical application. We give a necessary and sufficient condition of this
distillability. This condition can be expressed as: there exists
distillable-subspaces. According to this condition, one can judge whether a
mixed state is distillable or not easily. We also analyze some properties of
distillable-subspaces, and discuss the most efficient purification protocols.
Finally, we discuss the distillable enanglement of two-quibt system for the
case of finite copies.Comment: a revised versio
EFFECTS OF CONCENTRIC VERSUS ECCENTRIC TRAINING ON MUSCLE STRENGTH AND NEUROMUSCULAR ACTIVATION
Eccentric contraction (EC) involves fewer motor units but produces more tension than concentric contraction (CC) (Kay, 2000). Both EC and CC training can stimulate strength gain (Miller, 2006). However, it is not clear whether one method is more effective than the other and the effect of each training on motor units recruited after training. The purpose of this study was to compare the effects of EC and CC isokinetic training exercises on quadriceps muscle strength and neuromuscular activations
Self-Esteem, Resilience, Social Support, and Acculturative Stress as Predictors of Loneliness in Chinese Internal Migrant Children: A Model-Testing Longitudinal Study
The present study examined the risk and protective factors of loneliness among Chinese internal migrant children (CIMC) in Beijing, China, including self-esteem, resilience, social support, and acculturative stress. Longitudinal survey data were collected from a large sample of 4th, 5th, and 6th grade CIMC from three schools in Beijing, at four time points (N=862 at T1 to N=837 at T4) over a 20-month period. Grounded in the Cultural and Contextual Model of Coping and the Acculturation Theory, two predictor models of loneliness were tested with path analysis. The results yielded the following: a) the two predictor models fit the data well; b) CIMC’s T1 self-esteem and T1 resilience protected them against loneliness at T4; and c) CIMC’s T2 social support seeking was a significant mediator between self-esteem and loneliness, and between resilience and loneliness; and d) similarly, CIMC’s T3 acculturative stress was a significant mediator between self-esteem and loneliness, and between resilience and loneliness. The study’s results highlight the merit and importance of implementing theoretically-guided, model-testing research grounded in a prospective research design, to help advance CIMC research. Implications for future research on and practical support for CIMC are discussed
Experimental preparation of Werner state via spontaneous parametric down-conversion
We present an experiment of preparing Werner state via spontaneous parametric
down-conversion and controlled decoherence of photons in this paper. In this
experiment two independent BBO (beta-barium borate) crystals are used to
produce down-conversion light beams, which are mixed to prepare Werner state.Comment: 6 pages, 4 figures and 2 table
Reducing the communication complexity with quantum entanglement
We propose a probabilistic two-party communication complexity scenario with a
prior nonmaximally entangled state, which results in less communication than
that is required with only classical random correlations. A simple all-optical
implementation of this protocol is presented and demonstrates our conclusion.Comment: 4 Pages, 2 Figure
B_c meson rare decays in the light-cone quark model
We investigate the rare decays
and in the framework of the
light-cone quark model (LCQM). The transition form factors are calculated in
the space-like region and then analytically continued to the time-like region
via exponential parametrization. The branching ratios and longitudinal lepton
polarization asymmetries (LPAs) for the two decays are given and compared with
each other. The results are helpful to investigating the structure of
meson and to testing the unitarity of CKM quark mixing matrix. All these
results can be tested in the future experiments at the LHC.Comment: 9 pages, 11 figures, version accepted for publication in EPJ
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