Signal-Aligned Network Coding in K-User MIMO Interference Channels with Limited Receiver Cooperation

In this paper, we propose a signal-aligned network coding (SNC) scheme for K-user time-varying multiple-input multiple-output (MIMO) interference channels with limited receiver cooperation. We assume that the receivers are connected to a central processor via wired cooperation links with individual limited capacities. Our SNC scheme determines the precoding matrices of the transmitters so that the transmitted signals are aligned at each receiver. The aligned signals are then decoded into noiseless integer combinations of messages, also known as network-coded messages, by physical-layer network coding. The key idea of our scheme is to ensure that independent integer combinations of messages can be decoded at the receivers. Hence the central processor can recover the original messages of the transmitters by solving the linearly independent equations. We prove that our SNC scheme achieves full degrees of freedom (DoF) by utilizing signal alignment and physical-layer network coding. Simulation results show that our SNC scheme outperforms the compute-and-forward scheme in the finite SNR regime of the two-user and the three-user cases. The performance improvement of our SNC scheme mainly comes from efficient utilization of the signal subspaces for conveying independent linear equations of messages to the central processor.Comment: 12 pages, 4 figures, submitted to the IEEE Transactions on Vehicular Technolog

Operator Splitting Monte Carlo Method for Aerosol Dynamics

Aerosol dynamics are described by the population balance equation (PBE). In principle, three typical methods (i.e., direct discretization, method of moments, and stochastic method) have been widely used to solve the PBE. Stochastic method is the most flexible among the three methods. However, stochastic method is computationally expensive. Recently, an operator splitting Monte Carlo (OSMC) method has been developed so as to improve the numerical efficiency while preserving the flexibility of the stochastic method. Within the OSMC, nucleation and surface growth are handled with deterministic means, while coagulation is simulated with a stochastic method (the Marcus‐Lushnikov stochastic process). The stochastic and deterministic treatments of various aerosol dynamic processes are synthesized under the framework of operator splitting. Here, the operator splitting errors of various schemes are analyzed rigorously, combined with concrete numerical examples. The analyses not only provide sound theoretical bases for selecting the most efficient operator splitting scheme for the usage of the OSMC, but also shed lights on how to adopt operator splitting in other PBE solving methods, i.e., direct discretization, method of moments, etc

Predictors of reputation through university social responsibility practices in a Malaysian private university: the customer’s perspective

Social responsibility has emerged tremendously as an important field of study in the past decades. Institutions today have realised the significance of being ethical in their operations in order to attract various stakeholders, especially the customers. However, majority of the past studies on social responsibility mainly focus on big corporations, while the influence of social responsibility practices in university remains understudied. The purpose of this study was to examine the predicting factors of University Social Responsibility (USR) practices and reputation from the students’ viewpoint on one of the private higher educational institutions in Malaysia. A survey method was employed using multistage sampling. Questionnaires were distributed and generating 400 valid responses. The data were then analysed using Pearson-Product Moment Correlation and Multiple Regression test (enter method) through the Statistical Package for the Social Sciences (SPSS) version 25.0. Based on the findings, all the seven USR dimension, namely operational responsibility, stakeholder’s (student) responsibility, university-firm relationship, legal responsibility, environmental values, philanthropy responsibility, and community engagement yielded positive and moderate relationships with reputation. In addition, multiple regression analysis showed that operational responsibility, university-firm relationship, legal responsibility, philanthropy responsibility, and community engagement were the significant predicting factors that can enhance reputation in the current context. Conclusion, limitations of the study, implications of the findings, and suggestions for future study are also discussed

Biliary complications in liver transplantation

Biliary complications of living donor liver transplantation remain common. The complications of biliary leakage and stricture result in substantial recipient morbidity. A major focus of liver transplantation research is the prevention and reduction of these complications through identification of the multiple factors that are conducive to them. Such factors include the donor bile duct anatomy and quality, and the techniques of donor hepatectomy, recipient hepatectomy, and ductal reconstruction. A low threshold for re-exploration for possible bile leakage prevents development of uncontrolled sepsis. Return of good graft function can usually be expected after successful early endoscopic treatment. Contingent measures of percutaneous transhepatic dilatation and stenting, and revision hepaticojejunostomy have to be exercised with utmost care to avoid hepatic artery injury which may results in graft loss