Banteng Liu

Transmission Power Optimization Algorithm in Wireless Ad Hoc Networks

Considering that nodes move in wireless ad hoc networks, network topology and node locations change. A single transmission power can not meet mobile ad hoc networks. This paper proposes transmission power optimization algorithm based on various nearest-neighbor distances algorithm. Transmission node is informed of neighbor node locations in its maximum transmission range through network location management or other means. Then it measures node density with various nearest-neighbor distances algorithm, and calculates the optimal transmission power in current network with free space model and two way propagation model. Finally nodes transmit data with optimal transmission power. NS2 simulation results show that transmission power optimization algorithm increases network throughput, and insignificantly increase packet delay time. In the meantime, it reduces network power consumption in dense region, as well as the proportion of isolated nodes and network fragmentation in sparse region.

Research on a wireless sensor network's modulation based on ultra wideband signals

This paper proposed a new wireless sensor networks modulation, multi-band OFDM modulation based on ultra wideband signals. The modulation used 7500(MHz) band from 3.1(GHz) to 10.6(GHz). The band was divided into thirteen same sub-bands. Each sub-band used OFDM modulation for transmission. The transmission node could adaptively choose one or more sub-bands to avoid interference according to reception nodes feedback about interference sub-bands. The simulation results show that the modulation provides a good robust interference and coexistence performance. It also has low transmission power, low reception power, high-speed transmission, large system capacity and strong anti-multipath. So it is a cost-effective way to be integrated in the WSN instead of traditional radio transceiver. The modulation has good application prospect.

Research on the network life of the sensor network

Along with the progress of science and technology, the sensor technology rapidly develop, miniature sensors appeared and were used in the world. Wireless sensor network is composed of sensors and base stations as network nodes, which in a variety of areas has very broad application prospects. The definition and calculation of sensor network life has caused great concern in the academic community. This article defined network life from actual application and theoretical research as: When stations cannot receive sensor signal, the sensor network death. In this model, this paper firstly simulated 100 sensors specific distribution images and the distribution images of each nodes communication range. By observing the distribution and combining the corresponding assumptions, we can get the number of adjacent nodes when the sensor sends the signal. Based on the limited condition when each node is sending signals, we can get the expectation of the number of each sensor has sent signal.

Nearest-Neighbor Clustering Power Control Algorithm for Wireless Sensor Networks

To prolong network lifetime, nearest-neighbor clustering power control algorithm is proposed. In the algorithm, k-means algorithm is used to divide nodes into k different clusters. Nearest-neighbor distances algorithm is used to calculate the optimal transmission power of nodes which are in the same cluster. Then sink node broadcasts to inform other nodes that they use optimal transmission power for communicating with neighbor nodes which are in the same cluster and use default maximum transmission power for communicating with neighbor nodes which are in the different clusters. Simulation results show that by selecting the appropriate parameters, NNCPCA can prolong network lifetime, reduce network latency time and enable cost-effective energy consumption. Under certain conditions, it is fit for multi-cluster wireless sensor networks.

Research on Teaching Reform Contents and Methods of SCM Curriculum in Zhejiang Shuren University

Compared with public undergraduate universities, the overall quality of students in Zhejiang Shuren University is relatively lower. Students learn SCM curriculum difficultly. In order to solve the problem, the teaching reform of SCM curriculum is researched to improve students’ initiative learning. Based on the actual situation, the contents of teaching reform such as curricular system construction, modern teaching laboratory construction, teaching methods reform and means improvement, curricular practical teaching reform, extracurricular practical system construction, reference material construction and online learning system construction are proposed. Teaching methods such as heuristic teaching, physical demonstration teaching and project teaching are proposed specially to stimulate students’ interest. SCM curricular reform has been carried out gradually. It achieves certain results and is recognized by students, internal colleagues and external experts.

Distributed Power Control Algorithms for Wireless Sensor Networks

To prolong network lifetime and reduce average energy consumption when nodes are unable to measure the distance to neighbor nodes or have not distance measuring hardwire, distributed power control algorithms for wireless sensor networks are proposed. SPCA and PPCA are used to calculate the transmission power according to local information (residual energy). In the SPCA, the interval of residual energy is uniformly divided into α sections. Each section corresponds to one transmission power from maximum power to minimum power. In the PPCA, the transmission power is polynomial function of residual energy. When network starts, all nodes transmit data to sink node with DLOR routing and calculated transmission power. Simulation results show that by selecting the appropriate parameters, SPCA and PPCA can prolong network lifetime and reduce average energy consumption. Under certain conditions, it is fit for wireless sensor networks in special situation.

The Optimization Model of Campus Network Port Resources Based on Queuing Theory

In this paper, give full consideration to the Internet utilization, waste rate, complaint rate and other indicators, building on the model about campus network issues. Through the study of campus information network this stochastic service system, analyzed the service quality and system resources this pair of contradictions, application of the principle of queuing theory, the mathematical model was established, determined the communication port number, and adjusted the charge system, on the basis of ensuring regular service quality indicators, making service facilities cost economic and reasonable.