468 research outputs found
A novel approach to identify the rate constants of ion channel of four-state-loop via partially observable information
AbstractAmong the equations between rate constants and the derivatives, the novel equations between rate constants and the moments of open and shut lifetime distribution for a given state set of Markov Chain are applied to identify the rate constants of ion channels. For gating scheme of ion channels of four-state-loop, it is derived by the underlying information that rate constants can be identified by their open lifetime and shut lifetime distributions at any two states
An Inequality for Reinsurance Contract Annual Loss Standard Deviation and Its Application
For reinsurance contract simulated annual losses, an inequality relating their standard deviation and mean is found,
σ
f
≥
m
f
μ
A
C
μ
A
, where the coefficient in the inequality is the square root of the ratio of numbers of zero losses years to numbers of non-zero losses years. The largest such coefficient is also proved to be the universal upper bound. As direct application of this inequality, bounds for other risk measures of reinsurance contract, the TVaR (average of the annual losses that are larger than a given loss), the probability of attaching (greater than a given attachment loss), and the probability of exceeding (the annual loss limit) are obtained, which in turn reveal the capability upper limit of the simulation approach
What Determines EP Curve Shape?
Propose use kurtosis divided by skewness squared as shape factor, and use the global or conditional minimum/maximum of this shape factor for selecting and differentiating distribution families. Semi-empirical formulas for that lower/upper bound are calculated for various distribution families, with the aid of Computer Algebra System, for fitting hard to match distributions. Previous studies show high CV distribution is hard to fit and simulate, this study extends that conclusion to cases with low CV but still hard to match EP curves, characterized by having shape factors close to 1. The maximal likelihood approach of distribution fit can tell us which distribution family is better suited for an empirical distribution, but the shape factor range information can tell us why a distribution cannot fit well, or is not suitable at all. So the shape factor, in a sense, determines the EP curve shape
Second language psychological speaking and listening needs: Scale development, symbiosis, and demographic differences
This study aimed to develop and validate two parallel scales to measure the psychological L2 speaking and listening needs of 863 English-as-a-foreign language (EFL) learners. The associations between three psychological needs (i.e., autonomy, competence, and relatedness) of L2 speaking and of L2 listening were examined to develop insights into oracy (i.e., integration of speaking and listening) in L2 communication. Subsequently, the impact of demographic variables was explored. The data, collected via a 5-point Likert-scale questionnaire, were analyzed through descriptive and correlation analysis, factor analysis, and ANOVA. Exploratory factor analysis was conducted to determine the factor structures, followed by confirmatory factor analysis for validation. Results demonstrated that the validity and reliability of the two developed scales were satisfactory. L2 speaking autonomy was significantly related to L2 listening autonomy, as were competence and relatedness. The three psychological needs of both L2 speaking and listening revealed varying patterns in terms of gender, major, university geographical context, schooling stage (first year to fourth year), and study-abroad experiences. The research findings reinforce the need for integration of L2 speaking and L2 listening when satisfying university students’ psychological needs, contribute to the research field with the measurement scales of psychological needs in L2 speaking and listening settings, and yield implications for teaching the two language skills integratedly.This study aimed to develop and validate two parallel scales to measure the psychological L2 speaking and listening needs of 863 English-as-a-foreign language (EFL) learners. The associations between three psychological needs (i.e., autonomy, competence, and relatedness) of L2 speaking and of L2 listening were examined to develop insights into oracy (i.e., integration of speaking and listening) in L2 communication. Subsequently, the impact of demographic variables was explored. The data, collected via a 5-point Likert-scale questionnaire, were analyzed through descriptive and correlation analysis, factor analysis, and ANOVA. Exploratory factor analysis was conducted to determine the factor structures, followed by confirmatory factor analysis for validation. Results demonstrated that the validity and reliability of the two developed scales were satisfactory. L2 speaking autonomy was significantly related to L2 listening autonomy, as were competence and relatedness. The three psychological needs of both L2 speaking and listening revealed varying patterns in terms of gender, major, university geographical context, schooling stage (first year to fourth year), and study-abroad experiences. The research findings reinforce the need for integration of L2 speaking and L2 listening when satisfying university students’ psychological needs, contribute to the research field with the measurement scales of psychological needs in L2 speaking and listening settings, and yield implications for teaching the two language skills integratedly
Aplicaciones de bambú para rediseñar productos estructurales
Aquest projecte es centra en explorar les propietats del bambú i la seva aplicació en el disseny amb l'objectiu de promoure el desenvolupament del disseny sostenible. S'analitzen les característiques materials, de processament, de disseny i culturals del bambú, s'explora el seu potencial en la creació d'estructures en l'àmbit del transport. En la fase de verificació, s'implementa el disseny d'estructures de bambú en el desenvolupament d'un xassís de cotxet de bebè, millorant la seva sostenibilitat i contingut cultural, i investigant la possibilitat de combinar-lo amb altres materials per augmentar la seva estabilitat i conveniència. Els resultats mostren el potencial del bambú en el disseny, proporcionant directrius i inspiració per a la sostenibilitat i la innovació. La seva aplicació en el disseny contribueix a millorar el rendiment dels productes i a promoure els objectius de desenvolupament sostenible. Aquest estudi ofereix una investigació sobre el bambú, així com orientació per a la pràctica de disseny en camps relacionats.Este proyecto se enfoca en explorar las propiedades del bambú y su aplicación en el diseño con el objetivo de promover el desarrollo del diseño sostenible. Se analizan las características materiales, de procesamiento, de diseño y culturales del bambú, se explora su potencial en la creación de estructuras en el campo del transporte. En la fase de verificación, se implementa el diseño de estructuras de bambú en el desarrollo de un chasis de cochecito de bebé, mejorando su sostenibilidad y contenido cultural, e investigando la posibilidad de combinarlo con otros materiales para aumentar su estabilidad y conveniencia. Los resultados muestran el potencial del bambú en el diseño, proporcionando pautas e inspiración para la sostenibilidad y la innovación. Su aplicación en el diseño contribuye a mejorar el rendimiento de los productos y promover los objetivos de desarrollo sostenible. Este estudio ofrece una investigación sobre el bambú, así como orientación para la práctica de diseño en campos relacionados.This project focuses on exploring the properties of bamboo and its application in design with the aim of promoting sustainable design development. The material, processing, design, and cultural characteristics of bamboo are analyzed, and its potential in creating structures in the field of transportation is explored. In the verification phase, bamboo structures are implemented in the development of a baby stroller chassis, improving its sustainability and cultural content, and investigating the possibility of combining it with other materials to increase stability and convenience. The results demonstrate the potential of bamboo in design, providing guidelines and inspiration for sustainability and innovation. Its application in design contributes to enhancing product performance and promoting sustainable development goals. This study offers research on bamboo as well as guidance for design practice in related fields
Efficient Procedure for Valuing American Lookback Put Options
Lookback option is a well-known path-dependent option where its
payoff depends on the historical extremum prices. The thesis focuses
on the binomial pricing of the American floating strike lookback put
options with payoff at time (if exercise) characterized by
where denotes the price of the underlying stock at time .
Build upon the idea of \hyperlink{RBCV}{Reiner Babbs Cheuk and
Vorst} (RBCV, 1992) who proposed a transformed binomial lattice
model for efficient pricing of this class of option, this thesis
extends and enhances their binomial recursive algorithm by
exploiting the additional combinatorial properties of the lattice
structure. The proposed algorithm is not only computational
efficient but it also significantly reduces the memory constraint.
As a result, the proposed algorithm is more than 1000 times faster
than the original RBCV algorithm and it can compute a binomial
lattice with one million time steps in less than two seconds. This
algorithm enables us to extrapolate the limiting (American) option
value up to 4 or 5 decimal accuracy in real time
Stability control for breath analysis using GC-MS
Gas chromatography mass spectrometry (GC-MS) instruments provide researchers and clinicians with a vast amount of information on sample composition, thus these instruments are seen as gold standard in breath analysis research. However, there are many factors that can confound the data measured by GC-MS instruments. These factors will make interpretation of GC-MS data unreliable for breath analysis research. We present in this paper detailed studies of two of these factors: instrument variation over time and chemical degradation of known biomarkers during storage in sorbent tubes. We found that a single quadrupole MS showed larger variability in measurements than a quadrupole time-of-flight MS when the same mixture of chemical standards was analysed for a period of up to 8 weeks. We recommend procedures of normalising the data. Moreover, the stability studies of breath biomarkers like thioethers, previously found indicative of malaria, showed that there is a need to store the samples in sorbent tubes at low temperature, 6 °C, for no more than 20 days to avoid the total decay of the chemicals
Shape Factor Asymptotic Analysis I
The shape factor defined as kurtosis divided by skewness squared K/S^2 is characterized as the only choice among all factors K/〖|S|〗^α ,α>0 which is greater than or equal to 1 for all probability distributions. For a specific distribution family, there may exists α>2 such that min〖K/〖|S|〗^α 〗≥1. The least upper bound of all such α is defined as the distribution’s characteristic number. The useful extreme values of the shape factor for various distributions which are found numerically before, the Beta, Kumaraswamy, Weibull, and GB2 Distribution, are derived using asymptotic analysis. The match of the numerical and the analytical results can be considered prove of each other. The characteristic numbers of these distributions are also calculated. The study of the boundary value of the shape factor, or the shape factor asymptotic analysis, help reveal properties of the original shape factor, and reveal relationship between distributions, such as between the Kumaraswamy distribution and the Weibull distribution
Shape factor asymptotic analysis II
Probability distributions with identical shape factor asymptotic limit formulas are defined as asymptotic equivalent distributions. The GB1, GB2, and Generalized Gamma distributions are examples of asymptotic equivalent distributions, which have similar fitting capabilities to data distribution with comparable parameters values. These example families are also asymptotic equivalent to Kumaraswamy, Weibull, Beta, ExpGamma, Normal, and LogNormal distributions at various parameters boundaries. The asymptotic analysis that motivated the asymptotic equivalent distributions definition is further generalized to contour analysis, with contours not necessarily parallel to the axis. Detailed contour analysis is conducted for GB1 and GB2 distributions for various contours of interest. Methods combing induction and symbolic deduction are crafted to resolve the dilemma over conflicting symbolic asymptotic limit results. From contour analysis build on graphical and analytical reasoning, we find that the upper bound of the GB2 distribution family, having the maximum shape factor for given skewness, is the Double Pareto distribution
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