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New radio in unlicensed spectrum (NR-U) is an exciting evolution of LTE-U/LAA from 4G LTE to 5G NR, which generates an opportunity to alleviate the spectrum crunch in future wireless networks by operating NR in unlicensed spectrum. Due to the openness of unlicensed spectrum, networks with heterogeneous radio access technologies (RATs) will coexist with NR-U, especially for the incumbent WiFi networks. In this paper, we first introduce a NR-U framework based on network slicing and spatial multiplexing, which can help on the management of networks with heterogeneous RATs. We then propose a synchronous RAT for the proposed NR-U network and derive a user group construction strategy to improve performance as well as provide flexibility for both cellular and WiFi users. Numerical results demonstrate the mutual benefits of the proposed RAT to both cellular and WiFi users.

Due to the explosive growth of mobile data demand and the scarcity of licensed spectrum, this paper introduces a triple-band heterogeneous network (HetNet), which consists of a sub-6GHz LTE in unlicensed (LTE-U) network, a millimeter wave (mmWave) network, and an LTE network. Compared with the traditional dual-band HetNets, the proposed triple-band HetNet is more adaptive to intricate urban wireless environment, insusceptible to adverse communication conditions, and can flexibly support various data rate requirements. To fully improve the performance of the whole HetNet, a joint network selection and resource allocation scheme has been introduced. Based on the proposed scheme, we derive a closed-form solution for resource allocation, and provide a criterion for network selection. Simulation results demonstrate the effectiveness of our algorithm.

Reaching a consensus in a group decision-making (GDM) usually costs plenty of time and resources, so how to minimize the total cost in a GDM process has become the focus of most researchers, which makes the construction of the minimum cost consensus models be the key research field in recent years. The aim of this paper is to propose two kinds of non-linear minimum cost consensus models: one considers all the individual decision makers (DMs), while the other focuses only on a particular DM. To do this, consensus models based on minimum cost and maximum return are constructed. By using the dual theory in quadratic programming, the economic significance of these two models is verified and their relationship is further explored.

This paper investigates the consensus problem based on minimum cost and maximum return by utilizing primal-dual programming models. The primal problem is a linear programming model based on minimum cost of reaching consensus, and its dual problem is a linear programming based on maximum return of reaching consensus. By using the dual linear programming theories, this paper not only discusses the relation between the minimum cost that the moderator paid the individuals and the maximum returns that the individuals expected to receive for changing the opinion, but also explored the relation between the unit cost that the moderator would pay each individual and the unit return that each individual would receive from the moderator.

In this paper the reverse engineering and software CATIA was used to create 3D model and virtual prototype of the car sunroof motion mechanism. Then the model was imported into Software ADAMS to create the virtual kinematics model. After that parameterized the model and an optimization design was carried out with sunroof motion mechanism in software ADAMS. Finally a transient dynamical FEA simulation and analysis about the motion mechanism were done with software ANSYS Workbench. The research work in this paper can not only improve the design quality and efficiency of car sunroof, and also shorten the product development period and cost.

Virtual reality takes full advantage of computer technology, multi-media technology, multi-sensors technology, network technology and so on to set up a senior computer interface between human and computer whose characters are immersion, interaction and conception. Virtual reality is a composition of various technologies, among which is an environment modelling technology,that is the establish of virtual environment, who is the most critical part of the effect reality of virtual reality. In the regular scene of virtual reality. We capture three-dimensional data to form model easily through traditional surveying methods, but as for irregular scene, traditional surveying methods appear not enough. We utilize 3D laser scanning technology to capture the surface sample points of real scene,that are point cloud data, in which way we can restructure any complex scene non-contactedly, quickly and high-accurately to solve the problem of irregular scene effectively.

In this paper the key technique in independent product development of car sunroof was researched. Firstly the reversal engineering and software CATIA were applied to create the 3D model and the virtual prototype. Then the 3D model was imported into ADAMS to create the dynamical simulation model. Finally the model was parameterized and the optimization design was carried out. The research work in this paper can shorten the product development period and reduce the development cost.

This paper presents firstly the structure and working principle of car sunroof. Then the reverse engineering and software CATIA were used to build the 3D model of motion mechanism of a car sunroof. Finally the 3D model was imported into software ADAMS to build the virtual Prototype. By applying with the software ADAMS the kinematic and dynamic character of sunroof motion mechanism components during sunroof opening and closing was calculated and studied. The calculated results can be used as the input datum for the design of others components of car sunroof, for example in the design of the power and speed of motor, the size and dimensions of soft shaft. The study in this paper can improve the design quality and efficiency of new sunroof product and it can also remarkably shorten the new product development period and cost.

In this paper the reverse engineering and Software Catia were applied to create the 3D digital model. Then the model was imported into ADAMS to build the virtual prototype. After that the key components which affect the movement characteristics of the sunroof were abstracted out to build the kinematic model. Then the virtual assembling, kinematics simulation and analysis were done with ADAMS software. Finally, a parameter optimization was done based on the study result of the simulation and analysis. The study in this paper can not only improve the design quality and development efficiency of new automotive sunroof productions, but also remarkably shorten the Production development period and reduce the development cost.

Performance measurement can be defined as the process of quantifying the efficiency and effectiveness of organisations and actions. This paper postulates a comprehensive supply chain performance measurement approach which evaluates a supply chain both from structure and operational levels. The paper first elaborates on why supply chain should be evaluated from these two levels, and then performance indices used in structure and operational level evaluation are identified and related calculation model is proposed. The paper also discusses the relationships of the indices, and suggests that simulation could be applied to build supply chain models both on structure and process levels for evaluation purpose.

To improve dynamic response performance of traditional signal-planning for bus priority, this paper brings forward a new traffic signal timing scheme, which is composed of four modules: preprocessor of traffic information, mid-scope scheme generator, real-time scheme generator and final scheme mediation. The experiment shows that the scheme has better dynamic response performance while remaining well static response performance of traditional one and it is applicable in a wide range of traffic volume.

A novel robust anti-collusion encoding scheme which combines the Balanced Incomplete Block Design (BIBD) code with Turbo code in digital fingerprinting system is proposed. The fingerprints are coded by Turbo code before embedding and added to the wavelet domain which is suitable for the visual characteristics of human. The experimental results indicate that the proposed algorithm can successfully resist not only the collusion attacks by colluders, but also the other attacks such as noise when the digital products are transmitted in the channel. Meanwhile it can decrease the bit error rate (BER) of the fingerprints and enhance the overall resistance of the system.