1,408 research outputs found
Study for the development of a fabrication technology of the Antheraea pernyi fibroin (サクサン(Antheraea pernyi)フィブロインの加工技術開発に関する研究)
信州大学(Shinshu university)博士(工学)ThesisROZET SELENE. Study for the development of a fabrication technology of the Antheraea pernyi fibroin (サクサン(Antheraea pernyi)フィブロインの加工技術開発に関する研究). 信州大学, 2019, 博士論文. 博士(工学), 甲第697号, 平成31年03月20日授与.doctoral thesi
Some results on homoclinic and heteroclinic connections in planar systems
Consider a family of planar systems depending on two parameters and
having at most one limit cycle. Assume that the limit cycle disappears at some
homoclinic (or heteroclinic) connection when We present a method
that allows to obtain a sequence of explicit algebraic lower and upper bounds
for the bifurcation set The method is applied to two quadratic
families, one of them is the well-known Bogdanov-Takens system. One of the
results that we obtain for this system is the bifurcation curve for small
values of , given by . We obtain
the new three terms from purely algebraic calculations, without evaluating
Melnikov functions
Score-based Data Assimilation
Data assimilation, in its most comprehensive form, addresses the Bayesian
inverse problem of identifying plausible state trajectories that explain noisy
or incomplete observations of stochastic dynamical systems. Various approaches
have been proposed to solve this problem, including particle-based and
variational methods. However, most algorithms depend on the transition dynamics
for inference, which becomes intractable for long time horizons or for
high-dimensional systems with complex dynamics, such as oceans or atmospheres.
In this work, we introduce score-based data assimilation for trajectory
inference. We learn a score-based generative model of state trajectories based
on the key insight that the score of an arbitrarily long trajectory can be
decomposed into a series of scores over short segments. After training,
inference is carried out using the score model, in a non-autoregressive manner
by generating all states simultaneously. Quite distinctively, we decouple the
observation model from the training procedure and use it only at inference to
guide the generative process, which enables a wide range of zero-shot
observation scenarios. We present theoretical and empirical evidence supporting
the effectiveness of our method
Dynamics of apparent horizons in quantum gravitational collapse
We study the gravitational collapse of a massless scalar field within the
effective scenario of loop quantum gravity. Classical singularity is avoided
and replaced by a quantum bounce in this model. It is shown that, quantum
gravity effects predict a threshold scale below which no horizon can form as
the collapse evolves towards the bounce.Comment: Contribution to the Spanish Relativity Meeting in Portugal 2012
(ERE2012), Guimaraes, Portuga
Low-dose RUTF protocol and improved service delivery lead to good programme outcomes in the treatment of uncomplicated SAM: a programme report from Myanmar.
The treatment of uncomplicated severe acute malnutrition (SAM) requires substantial amounts of ready-to-use therapeutic food (RUTF). In 2009, Action Contre la Faim anticipated a shortfall of RUTF for their nutrition programme in Myanmar. A low-dose RUTF protocol to treat children with uncomplicated SAM was adopted. In this protocol, RUTF was dosed according to beneficiary's body weight, until the child reached a Weight-for-Height z-score of ≥-3 and mid-upper arm circumference ≥110 mm. From this point, the child received a fixed quantity of RUTF per day, independent of body weight until discharge. Specific measures were implemented as part of this low-dose RUTF protocol in order to improve service quality and beneficiary support. We analysed individual records of 3083 children treated from July 2009 to January 2010. Up to 90.2% of children recovered, 2.0% defaulted and 0.9% were classified as non-responders. No deaths were recorded. Among children who recovered, median [IQR] length of stay and weight gain were 42 days [28; 56] and 4.0 g kg(-1) day(-1) [3.0; 5.7], respectively. Multivariable logistic regression showed that children older than 48 months had higher odds of non-response to treatment than younger children (adjusted odds ratio: 3.51, 95% CI: 1.67-7.42). Our results indicate that a low-dose RUTF protocol, combined with specific measures to ensure good service quality and beneficiary support, was successful in treating uncomplicated SAM in this setting. This programmatic experience should be validated by randomised studies aiming to test, quantify and attribute the effect of the protocol adaptation and programme improvements presented here
Investigation of slow collisions for (quasi) symmetric heavy systems: what can be extracted from high resolution X-ray spectra
We present a new experiment on (quasi) symmetric collision systems at
low-velocity, namely Ar ions ( a.u.) on gaseous Ar and N
targets, using low- and high-resolution X-ray spectroscopy. Thanks to an
accurate efficiency calibration of the spectrometers, we extract absolute X-ray
emission cross sections combining low-resolution X-ray spectroscopy and a
complete determination of the ion beam - gas jet target overlap. Values with
improved uncertainty are found in agreement with previous results
\cite{Tawara2001}. Resolving the whole He-like Ar Lyman series from
to 10 with our crystal spectrometer enables to determine precisely the
distribution of the electron capture probability and the
preferential level of the selective single-electron capture.
Evaluation of cross sections for this process as well as for the contribution
of multiple-capture is carried out. Their sensitivity to the
-distribution of levels populated by single-electron capture is
clearly demonstrated, providing a stringent benchmark for theories. In
addition, the hardness ratio is extracted and the influence of the decay of the
metastable state on this ratio is discussed
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