11,270 research outputs found
Some results on two-sided LIL behavior
Let {X,X_n;n\geq 1} be a sequence of i.i.d. mean-zero random variables, and
let S_n=\sum_{i=1}^nX_i,n\geq 1. We establish necessary and sufficient
conditions for having with probability 1, 0<lim sup_{n\to
\infty}|S_n|/\sqrtnh(n)<\infty, where h is from a suitable subclass of the
positive, nondecreasing slowly varying functions. Specializing our result to
h(n)=(\log \log n)^p, where p>1 and to h(n)=(\log n)^r, r>0, we obtain
analogues of the Hartman-Wintner LIL in the infinite variance case. Our proof
is based on a general result dealing with LIL behavior of the normalized sums
{S_n/c_n;n\ge 1}, where c_n is a sufficiently regular normalizing sequence.Comment: Published at http://dx.doi.org/10.1214/009117905000000198 in the
Annals of Probability (http://www.imstat.org/aop/) by the Institute of
Mathematical Statistics (http://www.imstat.org
Supply chain contracting with competing regretful retailers
We study a two-tier supply chain with demand uncertainty where retailers experience regret from ex-post inventory error. With a monopolist retailer, we find that individual rationality can lead to supply chain coordination and creates non-trivial differences between regret and other reference points previously shown to be mathematically equivalent. Under competition, inventory regret can lead to either a separating or a pooling equilibrium despite the heterogeneity in their disutility from regret. The potential for a separating or pooling equilibria also differs substantially from the extant literature with implications for the wholesale price contracts and how competition dynamics impact industry service levels
What is the impact of hotels on local economic development? Applying value chain analysis to individual businesses
The impact of mainstream tourist hotels on destination economies is clearly an important question for public policy-makers wishing to develop robust tourism policy. We adapt the methodology of value chain analysis to measure the local economic impact of a large, single tourism enterprise, to show how to generate commercially realistic data using the example of an analysis of a 1000 room all-inclusive resort in southern Turkey in partnership with TUI UK and Ireland. The data break down package revenues according to their beneficiaries and identifies areas for improvement. We further report and reflect on a 6-month evaluation of a tour operator-hotel partnership to deliver on a set of positive recommendations arising from the date to improve future impact
Probability representation and quantumness tests for qudits and two-mode light states
Using tomographic-probability representation of spin states, quantum behavior
of qudits is examined. For a general j-qudit state we propose an explicit
formula of quantumness witnetness whose negative average value is incompatible
with classical statistical model. Probability representations of quantum and
classical (2j+1)-level systems are compared within the framework of quantumness
tests. Trough employing Jordan-Schwinger map the method is extended to check
quantumness of two-mode light states.Comment: 5 pages, 2 figures, PDFLaTeX, Contribution to the 11th International
Conference on Squeezed States and Uncertainty Relations (ICSSUR'09), June
22-26, 2009, Olomouc, Czech Republi
A new noncontact method for the prediction of both internal thermal resistance and junction temperature of white light-emitting diodes
Although critical to the lifetime of LED, the junction temperature of LED cannot be measured easily. Based on the general photoelectrothermal theory for LED systems, the coefficient for the reduction of luminous efficacy with junction temperature is first related to the characteristic temperature of the LED. Then, a noncontact method for estimating the internal junction temperature T j and junction-case thermal resistance R jc of LED from the external power and luminous flux measurements is presented and verified practically. Since these external measurements can be obtained easily, the proposal provides a simple tool for checking T j in new LED system designs without using expensive or sophisticated thermal monitoring equipment for the LED junctions. The proposed method has been checked with measurements on LED devices from three different brands with both constant and nonconstant R jc. The theoretical predictions are found to be highly consistent with practical measurements. © 2011 IEEE.published_or_final_versio
Novel self-configurable current-mirror techniques for reducing current imbalance in parallel Light-Emitting Diode (LED) strings
Traditional current-mirror methods require one fixed current reference for controlling other current source or sources. In this paper, a new self-configurable current-mirror method that can dynamically determine the best current branch as the current reference in order to ensure good balance of all parallel current sources is proposed. The operating principle involves a dynamic and self-configurable transistor-based current-balancing circuit that can be operated in saturation or linear mode. In either operating mode, good current balance or sharing among all parallel-connected current sources can be guaranteed. The novel current-balancing circuit does not require a separate power supply for powering their control circuits. The proposal is a modular one that can be expanded to any number of parallel current sources. Its principle has been successfully applied to current balancing of parallel LED strings. © 2011 IEEE.published_or_final_versio
Disentangling interglacial sea level and global dynamic topography: Analysis of Madagascar
© 2019 Global inventories of stable sea-level markers for the peak of the last interglacial period, Marine Isotopic Stage (MIS) 5e, play a pivotal role in determining sea-level changes and in testing models of glacial isostatic adjustment. Here, we present surveying and radiometric dating results for emergent terraces from northern Madagascar, which is generally regarded as a stable equatorial site. Fossil coral specimens were dated using conventional and open-system corrected uranium series methods. Elevation of the upper (undated) terrace decreases from 33.8 m to 29.5 m over a distance of 35 km. An intermediate terrace has an average radiometric age of 130.7±13.2 ka (i.e. MIS 5e). Its elevation decreases from 9.3 m to 2.8 m over a distance of 80 km. The record of the lowest terrace is fragmentary and consists of beach rock containing rare corals with ages of 1.6–3.8 ka. The spatial gradient of the MIS 5e marker is inconsistent with glacio-isostatic adjustment calculations. Instead, we propose that variable elevations of this marker around Madagascar, and possibly throughout the Indian Ocean, at least partly reflect spatial patterns of dynamic topography generated by sub-plate mantle convection
MiR-29b negatively regulates cell cycle activity of human embryonic stem cell-derived cardiomyocytes
published_or_final_versionThe 16th Medical Resarch Conference (MRC), The University of Hong Kong, Hong Kong, China, 22 January 2011. In Hong Kong Medical Journal, 2011, v. 17, suppl. 1, p. 50, abstract no. 7
Eigenlogic: a Quantum View for Multiple-Valued and Fuzzy Systems
We propose a matrix model for two- and many-valued logic using families of
observables in Hilbert space, the eigenvalues give the truth values of logical
propositions where the atomic input proposition cases are represented by the
respective eigenvectors. For binary logic using the truth values {0,1} logical
observables are pairwise commuting projectors. For the truth values {+1,-1} the
operator system is formally equivalent to that of a composite spin 1/2 system,
the logical observables being isometries belonging to the Pauli group. Also in
this approach fuzzy logic arises naturally when considering non-eigenvectors.
The fuzzy membership function is obtained by the quantum mean value of the
logical projector observable and turns out to be a probability measure in
agreement with recent quantum cognition models. The analogy of many-valued
logic with quantum angular momentum is then established. Logical observables
for three-value logic are formulated as functions of the Lz observable of the
orbital angular momentum l=1. The representative 3-valued 2-argument logical
observables for the Min and Max connectives are explicitly obtained.Comment: 11 pages, 2 table
Left ventricular mechanics in repaired tetralogy of Fallot with and without pulmonary valve replacement: analysis by three-dimensional speckle tracking echocardiography
published_or_final_versio
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