Time--space harmonic polynomials relative to a L\'{e}vy process

In this work, we give a closed form and a recurrence relation for a family of time--space harmonic polynomials relative to a L\'{e}vy process. We also state the relationship with the Kailath--Segall (orthogonal) polynomials associated to the process.Comment: Published in at http://dx.doi.org/10.3150/07-BEJ6173 the Bernoulli (http://isi.cbs.nl/bernoulli/) by the International Statistical Institute/Bernoulli Society (http://isi.cbs.nl/BS/bshome.htm

Density-dependent effects as key drivers of intraspecific size structure of six abundant fish species in lakes across Europe

Fish size structure has traditionally been used for elucidating trophic interactions and patterns of energy transfer through trophic levels(Trebilco et al.2013). We analysed the siz estructure of six common freshwater fish species in several hundred European lakes. We found little effect on the strength of the environmental gradients of size structure. The intraspecific density-dependent effect was the strongest and most consistent predictor

Regional Destination and Brand Identity: The Case of Piedmont, Italy

In recent years, research relating to marketing promotion has focused on the concepts of place branding and destination branding. However, a number of gaps in the existing literature need to be addressed. For example, while there are many studies on tourists and destination brands, few studies have considered the internal perspective of relevant public stakeholders. Moreover, many studies on place branding have focused on either entire countries or individual cities, paying little attention to place branding at the regional and sub-regional level, apart from regions that are already wellknown brands. Through in-depth, semi-structured interviews with key stakeholders in the Piedmont region of Italy, this paper addresses this lack of research, and focuses on the internal views of the destination management organisations (DMOs) on the brand development and brand identity of their territories. The results show that the process of developing a brand identity in the region is influenced by issues related to fragmentation, cooperation and coordination

Experimental Study on Formation Characteristics and Laws of Dislocation and Stacking Fault during Cutting of Titanium Alloy

Formation characteristics and laws of dislocation and stacking fault during cutting of titanium alloy were investigated by TEM. Several crucial aspects of experiment, such as sample cutting, mechanical reduction of thickness, dimpling, and ion reduction of thickness, were carefully designed and implemented. Further, electron diffraction pattern, diffraction contrast image, and high resolution electron photomicrograph of α phase and β phase were observed and analyzed. Following those analyses, the formation characteristics and laws of dislocation and stacking fault were made clear. Research results show that the edge dislocations exist commonly in the diffraction contrast images and high resolution electron photomicrographs of α phase and β phase. The stacking fault energy is higher in β phase than in α phase. In addition, the extended dislocation is difficult to be seen in β phase, but it is easier to be produced in α phase

Leveraging online user feedback to improve statistical machine translation

In this article we present a three-step methodology for dynamically improving a statistical machine translation (SMT) system by incorporating human feedback in the form of free edits on the system translations. We target at feedback provided by casual users, which is typically error-prone. Thus, we first propose a filtering step to automatically identify the better user-edited translations and discard the useless ones. A second step produces a pivot-based alignment between source and user-edited sentences, focusing on the errors made by the system. Finally, a third step produces a new translation model and combines it linearly with the one from the original system. We perform a thorough evaluation on a real-world dataset collected from the Reverso.net translation service and show that every step in our methodology contributes significantly to improve a general purpose SMT system. Interestingly, the quality improvement is not only due to the increase of lexical coverage, but to a better lexical selection, reordering, and morphology. Finally, we show the robustness of the methodology by applying it to a different scenario, in which the new examples come from an automatically Web-crawled parallel corpus. Using exactly the same architecture and models provides again a significant improvement of the translation quality of a general purpose baseline SMT system