Exact Synchronization for Finite-State Sources

We analyze how an observer synchronizes to the internal state of a finite-state information source, using the epsilon-machine causal representation. Here, we treat the case of exact synchronization, when it is possible for the observer to synchronize completely after a finite number of observations. The more difficult case of strictly asymptotic synchronization is treated in a sequel. In both cases, we find that an observer, on average, will synchronize to the source state exponentially fast and that, as a result, the average accuracy in an observer's predictions of the source output approaches its optimal level exponentially fast as well. Additionally, we show here how to analytically calculate the synchronization rate for exact epsilon-machines and provide an efficient polynomial-time algorithm to test epsilon-machines for exactness.Comment: 9 pages, 6 figures; now includes analytical calculation of the synchronization rate; updates and corrections adde

Assessment of the potential of MERIS near-infrared water vapour products to correct ASAR interferometric measurements

Atmospheric water vapour is a major limitation for high precision Interferometric Synthetic Aperture Radar (InSAR) applications due to its significant impact on microwave signals. We propose a statistical criterion to test whether an independent water vapour product can reduce water vapour effects on InSAR interferograms, and assess the potential of the Medium Resolution Imaging Spectrometer (MERIS) near-infrared water vapour products for correcting Advanced SAR (ASAR) data. Spatio-temporal comparisons show c. 1.1mm agreement between MERIS and GPS/radiosonde water vapour products in terms of standard deviations. One major limitation with the use of MERIS water vapour products is the frequency of cloud free conditions. Our analysis indicates that in spite of the low global cloud free conditions (~25%), the frequency can be much higher for certain areas such as Eastern Tibet (~38%) and Southern California (~48%). This suggests that MERIS water vapour products show potential for correcting ASAR interferometric measurements in certain regions

Transverse Momentum Dependent Light-Cone Wave Function of B-Meson and Relation to the Momentum Integrated One

A direct generalization of the transverse momentum integrated(TMI) light-cone wave function to define a transverse momentum dependent(TMD) light-cone wave function will cause light-cone singularities and they spoil TMD factorization. We motivate a definition in which the light-cone singularities are regularized with non-light like Wilson lines. The defined TMD light-cone wave function has some interesting relations to the corresponding TMI one. When the transverse momentum is very large, the TMD light-cone wave function is determined perturbatively in term of the TMI one. In the impact $b$-space with a small $b$, the TMD light-cone wave function can be factorized in terms of the TMI one. In this letter we study these relations. By-products of our study are the renormalization evolution of the TMI light-cone wave function and the Collins-Soper equation of the TMD light-cone wave function, the later will be useful for resumming Sudakov logarithms.Comment: Minor change in text, 7 pages, two figure

Cancellous bone from porous Ti6A|4V by multiple coating technique

A highly porous T{i}6Al4V with interconnected porous structure has been developed in our previous study. By using a so-called “Multiple coating” technique, the porous T{i}6Al4V can be tailored to resemble cancellous bone in terms of porous structure and mechanical properties. A thin layer of T{i}6Al4V slurry was coated on the struts of base porous T{i}6Al4V to improve the pore structure. After two additional coating, pore sizes ranged from 100 μm to 700 μm, and the porosity was decreased from ∼90% to ∼ 75%, while the compressive strength was increased from 10.3 ± 3.3 MPa to 59.4 ± 20.3 MPa and the Young's modulus increased from 0.8 ± 0.3 GPa to 1.8 ± 0.3 GPa. The pore size and porosity are similar to that of cancellous bone, meanwhile the compressive strength is higher than that of cancellous bone, and the Young's modulus is between that of cancellous bone and cortical bone. Porosity, pore size and mechanical properties can be controlled by the parameters in such multiple coating processes. Therefore the porous T{i}6Al4V with the characteristics of cancellous bone is expected to be a promising biomaterial for biomedical applications

Theory for Decoupling in High-T_c Superconductors from an Analysis of the Layered XY Model with Frustration

The nature of decoupling in the mixed phase of extremely type-II layered superconductors is studied theoretically through a duality transformation of the layered XY model with frustration. In the limit of weak coupling, we generally find that the Josephson effect is absent if and only if the phase correlations within isolated layers are short range. In the case specific to uniform frustration, we notably identify a decoupled pancake vortex liquid phase that is bounded by first-order and second-order decoupling lines in the magnetic field vs. temperature plane. These transitions potentially account for the flux-lattice melting and for the flux-lattice depinning that is observed in clean high-temperature superconductors.Comment: 11 pgs. of Plain TeX, 1 postscript fig., based on a talk given at the VORTEX Euroconference held in Heraklion, Crete, Sept. 199

Reliability-based code revision for design of pile foundations: Practice in Shanghai, China

AbstractThis paper describes how the code for the design of pile foundations in Shanghai, China is revised based on the reliability theory. With quality static load test data, both within-site and cross-site variabilities for design methods of piles in Shanghai are characterized. It is found that the amount of uncertainties associated with the design of piles in Shanghai is less than the typical values reported in the literature. With the partial factors specified in the previous design code, the reliability indexes of piles designed with empirical methods are in the range of 3.08–4.64, while those of piles designed with the load test-based method are in the range of 5.67–5.89. The load factors in the revised local design code have been reduced according to the national design code. As a result, the resistance factors have been increased in the revised code based on a combination of a reliability analysis and engineering judgment. In the revised design code, the reliability level of piles designed with the empirical methods is similar to that in the previous design code; the reliability level of piles designed with the load test-based method is lowered to achieve cost-effectiveness. Partial factors have been suggested for side and toe resistances based on the reliability theory considering their relative importance as well as the uncertainties involved

Factors of having influence on the rheological properties of Ti6A14V slurry

A highly porous Ti6Al4V could be produced with a porous polymeric sponge and Ti6Al4V slurry. However, the rheological properties of Ti6Al4V slurry appeared to be the key issue in the preparation of porous Ti6Al4V. In this study, factors having influence on the rheological properties of Ti6Al4V slurry were addressed in detail. Ti6Al4V powders, organic thickening agents (binders), dispersants, concentration of powder and pH values were optimised with regard to the rheological properties of Ti6Al4V slurry. The results show that Ti6Al4V powder with a mean diameter of 45 μm and spherical shape is beneficial for the preparation of Ti6Al4V slurry. Meanwhile binders with two ingredients, which decompose at different temperatures, have the advantage to keep the shape after debinding. The optimised procedure, based on the findings, made it possible to produce highly porous Ti6Al4V with reticulate porous structure. Porous Ti6Al4V produced by this way is expected to be a promising biomaterial for tissue engineering scaffolds and orthopaedic implant applications

On Transverse-Momentum Dependent Light-Cone Wave Functions of Light Mesons

Transverse-momentum dependent (TMD) light-cone wave functions of a light meson are important ingredients in the TMD QCD factorization of exclusive processes. This factorization allows one conveniently resum Sudakov logarithms appearing in collinear factorization. The TMD light-cone wave functions are not simply related to the standard light-cone wave functions in collinear factorization by integrating them over the transverse momentum. We explore relations between TMD light-cone wave functions and those in the collinear factorization. Two factorized relations can be found. One is helpful for constructing models for TMD light-cone wave functions, and the other can be used for resummation. These relations will be useful to establish a link between two types of factorization.Comment: add more discussions and reference