Advanced Materials Research Vols. 143-144

Abstract: Personalized recommendation methods are mainly classified into content-based recommendation approach and collaborative filtering recommendation approach. However, Both recommendation approaches have their own drawbacks such as sparsity, cold-start and scalability. To overcome the drawbacks, In this paper, we propose a framework for recommender systems that join use of Ontology and Bayesian Network. On the one hand, Ontology help formally defining the semantics of variables included in the Bayesian network, thus allowing logical reasoning on them. On the other hand, Bayesian network allow reasoning under uncertainty, that is not possible only with the use of ontology. In the recommendation, products not yet purchased or rarely purchased can still be recommended to customers with accuracy.

Abstract: Recent achievements in III-nitride semiconductor structures growth have allowed ultraviolet (UV) photo-detectors based on these compounds to be well established today. In this article, AlGaN film of 1-μm thickness was grown on Al2O3 substrate by metal-organic chemical vapor deposition (MOCVD). The AFM was used to analyze the surface morphology of the AlGaN film; X-ray diffraction measurements were used to study the quality of the film’ crystal structure; Cathode-ray luminescence(CL) was employed to study the luminescence properties of the AlGaN film. The result shows that there is a single atom layer on the AlGaN film’surface, and it shows that a low-defect-density AlGaN film with good surface morphology and single crystal Hexagonal structure has been obtained. It is found that there is some relationship between the film’crystal structure , dislocations and the luminescence properties . PACS: 73.61.

Abstract: Benefits assignment in the construction machinery supply chain business cooperation is the crucial and the most prominent conflicts issue, it plays a decisive role on sustained and stable development of cooperative relations. In this paper, the cooperative game theory and methods applied to the benefit assignment in the construction machinery supply chain management, and on this basis, the benefits of various cooperative enterprises are assigned by a comprehensive cooperative game model with the Shapley value model including risk of correction factor and the investment weight correction factor according to investment in the construction machinery supply chain, while a numerical example to demonstrate the method of science and rationality.

Abstract: Since the Internet users in China increased gradually, we use the Bass model to forecast the number of the Internet users in china in the following years, and establish the model to forecast the B2B e-commerce transaction volume of China. With the estimation of model parameters, we analysis the reasons of the E-commerce development in china, and give some policies or proposals which might be help for the high-speed development of the E-commence in China.

Abstract: Parametric model of floating raft vibration isolation and shock resistance system was built. Optimization techniques of exploitation combined with exploration was brought forward with NCGA used in global and MMFD used in local optimization. Multi-objective optimization design frame was set up in the paper and the Pareto optimal sets were given. At last the method of deducing design variables from Pareto sets was brought forward.

Abstract: For a class of strict-feedback nonlinear systems with unknown constant parameters, uncertainty in the input gains and standard Wiener-noise, combining the system function with the known reference signal, the error system is obtained. The adaptive inverse optimal controller and adaptive laws of parameters are designed using Backstepping algorithm, thus the robust adaptive inverse optimal tracking problem of original system is solved．

Abstract: An efficient and convenient way to levitate and manipulate micro beads is reported, in which coils and soft magnetic materials are used to generate a magnetic field. The levitation is based on diamagnetic buoyancy, and the main structure of this device is made into spiral switch arrays so as to simplify the interconnection and magnetic field control. The design, modeling and fabrication of the device for manipulation of diamagnetic beads is given in detail. Theoretic analysis and experimental results of fabrication indicate the advantages and feasibility of the proposal illustrated here.

Abstract: Time-space patterns of activity-travel are very complex, because the individual movement in time-space is a complex trajectory with many interacting dimensions. Potentially huge amounts of time-space data will be collected for different purposes by GPS receivers, and existing analytical tools in GIS may prove to be insufficient to handle these data. The purpose of this paper is to design a human-computer interface to model and visualize mobile objects with GPS data, in order to find an effective method to construct interactive manipulative 3D-GIS software of activity-travel patterns. The methods of 3D geographical data gathering and 3D map modeling are also present to support the analysis, display, and animation of time and space data. A prototype was implemented using the software of Multigen Creator and Vega to analyze GPS-recorded travel data in the city of Changchun, China. It allows the user to interact and explore the 3D map. Not only the visual properties of objects can be altered to reflect their various attributes, the highly flexible viewing and navigational environment is also a great help to the users.

Abstract: Pressure sensitive paint (PSP) has become a useful tool to measure the surface pressure distribution of aerodynamic components replacing conventional pressure taps. For the PSP technique based on the luminescence quenching by oxygen, improvement of its sensitivity is important. In this study, we synthesized palladium octaethylporphyrin (PdOEP) as luminophor and embeded PdOEP in polydimethylsiloxane (PDMS) as polymeric binder to make up of pressure sensitive paints. We used UV/Vis spectrometer and spectrofluorimeter to study the absorption and phosphorescence spectra of PdOEP. In addition, by our self-made experimental setup, the sensitivity of PSPs were examined especially in the range of pressure below 150 Pa. As a result, it is clarified that the PSP using PdOEP as a luminophore and using PDMS as a binder has very high sensitivity to oxygen pressure in low pressure conditions below 150 Pa.

Abstract: The objective of this work is to investigate the influence of measuring frequency on the internal friction of Ti50Ni48.5Fe1.5 shape memory alloy. The DSC, DC electrical resistivity and internal friction measurements were employed to characterize the sample in this study. Comparing the DSC result, the two internal friction peaks were confirmed which are corresponding to the R-phase transformation and martensitic transformation of Ti50Ni48.5Fe1.5 alloy during the cooling process, respectively. The height of internal friction peak corresponding to martensitic transformation increased with decreasing of measuring frequency. But, the height of the internal friction peak corresponding to R-phase transformation exhibited little measuring frequency dependence. Meanwhile, the value of the relative modulus peaks of the specimen increased with measuring frequency increasing. Furthermore, there was an interesting phenomenon that the martensitic transformation finish temperature shifted to higher temperature side with increasing of measuring frequency. It could be associated with the variation of applied vibration energy.