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Planning of base stations (BS) is one of the fundamental problems in the fourth generation (4G) wireless network design. A new mathematical model for the 4G BS planning is proposed in this paper. The co-channel interference, orthogonal frequency division multiplexing (OFDM), the cell edge rate, the reference signal received power (RSRP) and the base station density are considered in detail in this model. The objectives of the model are to minimum construction cost, maximum coverage and capacity at the same time. It's a multiobjective optimization problem with constraints. So a multiobjective algorithm with a local search operator is designed to solve this model. Simulation results show that the according algorithm with local search operator can give a set of solutions with relatively lower cost, larger coverage, larger capacity and faster speed than the algorithm without local search operator. The effective and efficient of the proposed model can also be identified by the comparison of the solutions.

In this paper, we propose reliability adjustment weighted bit-flipping (RA-WBF) decoding algorithm for low density parity-check (LDPC) codes. By adjusting the reliability of received symbols during iterative decoding, the proposed algorithm can offer better tradeoff between performance, convergence speed and computational complexity. Furthermore, this improvement can easily be extended to other variations of weighted bit-flipping decoding algorithm and obtain noticeable improvement in error performance. Simulation results are shown to verify our conclusions.

Aiming at the optimization algorithm, weak filled function method is proposed and which with simple form is constructed. The restriction of this method is weaker than the known filled function method, thus it is easier to construct function and solve algorithm. The weak filled function method is feasible through the theoretical analysis, and the global minimum of simulation example can be obtained in its interval. The results indicate that weak filled function method is an effective method.

UWB (Ultra-Wideband, UWB) is a short-range wireless transmission technology. For its high speed, low power, low complexity and low power spectral density, UWB is considered as the most important one of future wireless communications development directions. This paper focuses on the synchronization and channel parameters in UWB, and proposes the efficient closed-form estimation. In this paper, it is studied that the Hankel Matrix is constructed with the optimal number of columns in order to obtain the minimum element redundancy rate. Finally, the corresponding algorithm is designed, which not only can bring about the closed-form estimation, but also can greatly reduce the computation.

This paper provided a mathematic model for Three Gorges-Gezhou dam co-scheduling problems, based on full analysis of Three Gorges-Gezhou dampsilas actual needs, to maximize the total throughput of Three Gorges-Gezhou dam, to maximize the utilization ratio of shiplock area and minimize the total navigation shiplock waiting time under eight constraint conditions. Then a scheduling algorithm based on GA was pointed out. The Three Gorges south lock, Gezhou dam lock, the Three Gorges north lock were optimization searched separately in the GA algorithm. The scheduling results of the Three Gorges south lock were taken as the origin of the whole plan period, and also were taken as the basis of the Gezhou dam scheduling together with the ship applied information. The scheduling results of Gezhou dam were regarded as the basis of the Three Gorges north lock scheduling together with the ship applied information, so repeated, until the optimal scheduling results were given, or the most iterative step was reached. The applied result shows that making a period plan of two dam five lock only needs 2 minutes, and the plan is quite effective according to practical application.

As the Three Gorges Dam has put into operation, it is necessary to develop a co-scheduling navigation system for both the Three Gorges Dam and the Gezhouba Dam. The Navigation Co-scheduling System for the Three Gorges-Gezhouba Dams aims at ensuring safe, convenient and smooth navigation of the ships passing through both dams. The design and implementation of the Navigation Co-scheduling System for the Three Gorges-Gezhouba Dams are described. The general situation and core requirements are analyzed, followed with the structure of the Navigation Co-scheduling System, which is developed under Sun Microsystems's J2EE Architecture. Then we mainly focus on core J2EE patterns and in detail show how those design patterns, such as Front Controller, Intercepting Filter, Service Locator and Data Access Object Factory Strategies, are used and applied in different layers.

Evaluation exists in all kinds of trades, where the justness of evaluation and the preferences of evaluating experts have been brought into focus extensively. However, the research on justness of evaluation is still at the initial stages. This paper considers the justness of evaluation using the SVD (singular value decomposition) and dimensionality reduction model, analyzes "common judgment" of experts in evaluation. This paper contrasts the sort order of the evaluation objects according to the primary data with that after applying this model. Further, this paper use cluster analysis method to classify evaluating experts, likewise, after applying SVD&DR model.