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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.

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.

In order to improve the navigation capability of the ship locks in the traffic management and optimize the ship scheduling, at the engineering background of navigation co-scheduling of the Three Gorges Dam and Gezhouba Dam, a mathematic model is introduced with the scheduling principle of navigation constraints and first-come-first-served priority, and the objectives of maximizing the whole navigation capability, minimizing the total ships waiting time and the cost of used water, balancing the navigation capacity of the Three Gorges Dam and Gezhouba Dam. The co-scheduling takes comprehensive account of the two five-step ship locks of the Three Gorges Dam and three one-step ship locks of the Gezhouba Dam. As far as the structure of the model is concerned, the key of the model is focused on the global optimization of the whole navigation capacity of the two dams, and the local optimization for single ship lock should be taken into account. The output of the model is the scheduling plan, including the time sequence to open the lock gates and the set place information of the ships in each ship lock during the certain period of one plan. The scheduling plan is attributed to the scheduling problem of the time table from time aspect, coupled with bin packing problem from space aspect, so it is an NP-hard combinatorial optimization problem. To deal with this kind of navigation co-scheduling model, a novel constrained multi-objective heuristic algorithm (CMOHA) is accordingly designed. Through numerical experiment's analysis, illustrative results show that the navigation co-scheduling model is feasible, safe and efficient scheme for ship scheduling can be obtained, and the whole passing ability of the navigation establishment can be remarkably improved.

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.