Papers by Keyword: ASA

Abstract: “Authorized Shared Access” (ASA) is a spectrum management policy which enables the secondary system to opportunistically utilize the licensed spectrum of the primary systems. In the coexistence of LTE-A system with primary systems, one of the constituent cells of the CoMP cooperating set may be affected because it has to vacate the ASA frequency for it overlaps with the protected area of the primary system. As a result, the CoMP cooperating set will be changed, and the operation of the CoMP can’t be continued execution. In this case, the UE’s QoS can’t be guaranteed and even the UE experiences call drop when using the traditional method. In this paper, by utilizing a central controller, we propose an efficient method for managing CoMP cooperating set on the ASA spectrum. The change information about the affected cell is sent to the serving cell of the CoMP through the central controller in advance. Then, the serving cell may reselect a new CoMP cooperating set or determine CoMP information indicating whether the CoMP cooperating set will be continued based on this change information, which effectively ensures continued execution of CoMP and the UE’s QoS. Simulation results show that the proposed method can provide better performance compared with the traditional method.

Abstract: Global optimization algorithms have strong adaptability become a major research direction. Three global optimization algorithms which are Multi-Island Genetic Algorithm (MIGA), Adaptive simulated annealing (ASA) and Evolutionary Algorithms (EVOL) are adopted as the optimization policy. Tested with Zakharov function and Rastrigin function to analyze the performance of the global optimization algorithms.According to the results, it can be concluded that one should choose corresponding optimization methods for optimal calculation with specific issues, so that it can obtain the best optimal solution.

Abstract: Alkenyl succinic anhydride (ASA) is widely used to hydrophobize paper and paper board in papermaking industry. Montmorillonite (MMT) particles modified by trifunctional silylating agent were used as particulate emulsifier to prepare binary mixed sizing agent. It was found that stable ASA\liquid paraffin Pickering emulsions can be prepared by using grafted-MMT particles and the optimal dosage of LP oil was 50 vol.%. The ASALP Pickering emulsions exhibited some kinds of a solidlike viscoelastic behavior, which can be explained by the particulate network formed by grafted-MMT particles in the emulsion. Addition of LP oil not only improved the stability of ASA emulsions stabilized by particulate emulsifier, but also significantly promoted the internal paper sizing performance of ASA.

Abstract: Acrylonitrile-styrene-acrylate copolymer/polycarbonate (ASA/PC) blends were prepared over a range of compositions via mixing PC, SAN, and ASA copolymer by melt blending. An analysis was made on the mechanical properties and morphology of the blends. When a small amount SAN was introduced to ASA/PC blends, the dispersion condition of ASA in the matrix was improved and a better integrated mechanical properties was realized. Further increasing the SAN content led to a decrease of impact strength, which was due to the changing of the morphology of the blends and the inherent brittleness of matrix. Introduction

Abstract: Polymethyl methacrylate (PMMA)/ acrylonitrile-styrene-acrylate terpolymer (ASA) alloy was prepared via melt blending method. Effects of ASA melt flow rate and PMMA/ASA ratio on mechanical property of the alloy were studied. It showed that when the high melt flow rate ASA was used, alloy’s tensile strength and flexural strength were little different from using low melt flow rate ASA, while the impact strength was significantly higher than the latter. Differential scanning calorimetry (DSC) analysis showed that a glass transition (T_g) platform emerged in low melt flow rate ASA at 48.5°C, which represented the T_g of the interface phase formed between SAN grafted acrylate rubber particles and SAN matrix. Scanning electron microscope (SEM) experiment further showed that when low melt flow rate ASA was used, alloy’s cross section was smooth which showed the characteristics of brittle fracture.