Weighted Random Walk Sampling for Multi-Relational Recommendation

In the information overloaded web, personalized recommender systems are essential tools to help users find most relevant information. The most heavily-used recommendation frameworks assume user interactions that are characterized by a single relation. However, for many tasks, such as recommendation in social networks, user-item interactions must be modeled as a complex network of multiple relations, not only a single relation. Recently research on multi-relational factorization and hybrid recommender models has shown that using extended meta-paths to capture additional information about both users and items in the network can enhance the accuracy of recommendations in such networks. Most of this work is focused on unweighted heterogeneous networks, and to apply these techniques, weighted relations must be simplified into binary ones. However, information associated with weighted edges, such as user ratings, which may be crucial for recommendation, are lost in such binarization. In this paper, we explore a random walk sampling method in which the frequency of edge sampling is a function of edge weight, and apply this generate extended meta-paths in weighted heterogeneous networks. With this sampling technique, we demonstrate improved performance on multiple data sets both in terms of recommendation accuracy and model generation efficiency

On the Performance of Short Block Codes over Finite-State Channels in the Rare-Transition Regime

As the mobile application landscape expands, wireless networks are tasked with supporting different connection profiles, including real-time traffic and delay-sensitive communications. Among many ensuing engineering challenges is the need to better understand the fundamental limits of forward error correction in non-asymptotic regimes. This article characterizes the performance of random block codes over finite-state channels and evaluates their queueing performance under maximum-likelihood decoding. In particular, classical results from information theory are revisited in the context of channels with rare transitions, and bounds on the probabilities of decoding failure are derived for random codes. This creates an analysis framework where channel dependencies within and across codewords are preserved. Such results are subsequently integrated into a queueing problem formulation. For instance, it is shown that, for random coding on the Gilbert-Elliott channel, the performance analysis based on upper bounds on error probability provides very good estimates of system performance and optimum code parameters. Overall, this study offers new insights about the impact of channel correlation on the performance of delay-aware, point-to-point communication links. It also provides novel guidelines on how to select code rates and block lengths for real-time traffic over wireless communication infrastructures

Janssen effect and the stability of quasi 2-D sandpiles

We present the results of three dimensional molecular dynamics study of global normal stresses in quasi two dimensional sandpiles formed by pouring mono dispersed cohesionless spherical grains into a vertical granular Hele-Shaw cell. We observe Janssen effect which is the phenomenon of pressure saturation at the bottom of the container. Simulation of cells with different thicknesses shows that the Janssen coefficient $\kappa$ is a function of the cell thickness. Dependence of global normal stresses as well as $\kappa$ on the friction coefficients between the grains ($\mu_p$) and with walls ($\mu_w$) are also studied. The results show that in the range of our simulations $\kappa$ usually increases with wall-grain friction coefficient. Meanwhile by increasing $\mu_p$ while the other system parameters are fixed, we witness a gradual increase in $\kappa$ to a parameter dependent maximal value

Study the Relation between Working Capital System and Profitability in Auto Manufacturing Industry in India

The new economic policy adopted in India in 1991 known as Liberalization, Privatization and Globalization (LPG model). This policy  has been designed to make the Indian economy progressively market oriented and integrate it with the emerging global economy structure. Therefore, in line with this policy it was very indispensable to analyze the working management and some financial ratios in some selected Auto manufacturing companies. The purpose of the study was to analyze the practice of working capital Management and Asset and liquidity ratios in six selected Indian auto manufacturing companies. For this aforementioned study, a time series data for the years 2003- 2012 has been employed and a secondary data from the annual reports of the six companies was solicited. Both qualitative and quantitative paradigms were employed so as to analyze the research. Regarding  the relation between working capital and turnover analysis,  index of  inventory turnover, debtors turnover ratio, total assets turnover ratio and  fixed assets turnover ratio were used. . The minimum inventory turnover ratio chain index among all selected companies  was founded  in Ashok Leyland in 2009-2010 that was 74.60 and  the maximum was  founded in Maruti Suzuki that was  214.76 in 2010-2011. TVS Motor was denoted by the minimum debtors turnover ratio chain index among all selected companies in 2009-2010 that was 55.68 and the maximum debtors turnover ratio chain index was in Maruti Suzuki that was 438.51 in 2010-2011. TVS Motor was denoted by the minimum total assets turnover ratio chain index among all selected companies in 2008-2009  that was 43.15 and the maximum was Ashok Leyland in 2006-2007 that was 176.92. . The minimum fixed assets turnover ratio chain index  among selected companies was  founded in Ashok Leyland in 2009-2010 that was 61.94. The maximum fixed assets turnover ratio chain index among, selected companies was  founded in  Hero MotoCorp in 2005 -2006 that was 174.41. Keywords: Turnover, profitability, “Working capital Auto manufacturing companies”

Magnetic effects on the low-T/|W| instability in differentially rotating neutron stars

Dynamical instabilities in protoneutron stars may produce gravitational waves whose observation could shed light on the physics of core-collapse supernovae. When born with sufficient differential rotation, these stars are susceptible to a shear instability (the "low-T/|W| instability"), but such rotation can also amplify magnetic fields to strengths where they have a considerable impact on the dynamics of the stellar matter. Using a new magnetohydrodynamics module for the Spectral Einstein Code, we have simulated a differentially-rotating neutron star in full 3D to study the effects of magnetic fields on this instability. Though strong toroidal fields were predicted to suppress the low-T/|W| instability, we find that they do so only in a small range of field strengths. Below 4e13 G, poloidal seed fields do not wind up fast enough to have an effect before the instability saturates, while above 5e14 G, magnetic instabilities can actually amplify a global quadrupole mode (this threshold may be even lower in reality, as small-scale magnetic instabilities remain difficult to resolve numerically). Thus, the prospects for observing gravitational waves from such systems are not in fact diminished over most of the magnetic parameter space. Additionally, we report that the detailed development of the low-T/|W| instability, including its growth rate, depends strongly on the particular numerical methods used. The high-order methods we employ suggest that growth might be considerably slower than found in some previous simulations.Comment: REVTeX 4.1, 21 pages, 18 figures, submitting to Physical Review

Arithmetical rank of the cyclic and bicyclic graphs

We show that for the edge ideals of the graphs consisting of one cycle or two cycles of any length connected through a vertex, the arithmetical rank equals the projective dimension of the corresponding quotient ring