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Rural land circulation is a hot topic of land resource management and research. It involves the nature of land use changes, land changes, cadastral ownership relations change and many other content, with the aid of GIS technology can be efficient, high-quality completion of these work. Based on the scientific, practical and reliable principles, this paper realized a visible system of abstract data about rural land circulation by coupling the comprehensive performance evaluation model of rural land circulation with GIS Technology. According to this system, we are able to analyse the impact of land transfer on society. Furthermore, the analysis mentioned above affords strong theoretical foundation for agricultural sector to make decisions. Finally, based on the rural land circulation data of specific township, the system is applied to analyse the impact of land transfer on this town then change the allocation of land resources for better in the future.

The No.1 Document of the Party Central Committee put forward to carry out a comprehensive rural land approval registration certification work in 2013. In response to the call, the Ministry of Agriculture accelerate the development of rural land approval registration certification work, to further stabilize the land contract relations, promote land transfer and scale development, add new energy for the agriculture development. By 2016, more than 90% of the country had already carried out land approval work, so this paper employs the rural land approval data to study economy growth on the role of rural land approval agglomeration in most provinces of China in 2016. With applying the geographic information systems in the application, forecasting the model of rural land approval and economic growth is the inevitable trend in development. This article in view of spatial information systems researching in the rural land approval distribution is to make prediction of the toughest task. The results show that rural land approval agglomeration has a significant positive role in the regional economic growth in different models divided by two groups. Then we use universal Kriging prediction model to analysis and validate the correction.

Dithering particle swarm optimization (DPSO) algorithm is introduced into adaptive polarization mode dispersion (PMD) compensation in optical communication system. The DPSO algorithm has the merits of rapid convergence to the global optimum, without being trapped in local sub-optima, and good robustness to noise. How to implement DPSO as a component of a control algorithm in adaptive polarization mode dispersion compensation is described. Performance comparisons between PSO and DPSO were carried out theoretically and experimentally.

This paper presents the design and implementation of an Openflow-based Network Management System. The system consists of GUI, Floodlight Controller and Agent (s), and it enables monitoring, control and management of ROADMs. WSS and OPM are two main modules of a ROADM system. They are connected with an Agent through Protocol of Serial Port, while GUI communicates with Floodlight Controller by Socket Protocol.

Enslaved by atmospheric turbulence and transmission power, performance of Free-space Optical Communication (FSO) fluctuates greatly. A new communication system of MIMO-CPolSK combined the MIMO system and CPolSK modulation is proposed in this paper. According to the strength of turbulence, different mathematical models of atmospheric channel are adopted. The BER calculating formula of SISO-CPolSK is proposed at first, then the BER performance of MISO-CPolSK and MIMO-CPolSK system is presented. The result of numerical simulation shows that BER performance is greatly promoted in MIMO system and compared to OOK modulation, the SNR of receiving in CPolSK modulation is reduced about 3dB when the system has the same BER performance under the same condition.

A polarization stabilization control system based on digital signal processor (DSP) is proposed in this paper. The system uses low frequency radio frequency (RF) power as control signal for polarization stabilization, and it does not need high-speed circuit to track fast polarization change. Modified particle swarm optimization algorithm is utilized and the effectiveness of polarization stabilization control is experimentally verified.

Mobile Wireless Network Management System provides a new concept in the research of network management. Supported by mobile terminals, the work achieves the mobilization of network management which is of great convenience and efficiency.

This paper presents a new network management system which contains a user-friendly wireless mobile manager. Compared with traditional network management system, the new system realizes the mobile management of network.

We present an SDN-based control plane for elastic optical wavelength switch in optical networks, for dynamic end-to-end lightpath provisioning and maximum flexible operations. Detailed architecture and specific modules including underlying wavelength switch, SDN controller and applications are developed and evaluated to show its overall feasibility and efficiency.

As the scale of network become larger and larger together with node numbers, the traditional way to manage the network becoming more and more energy-wasting. In order to improve the performance of the network equipment, we figured out a method that can reduce CPU scheduled frequency thus resulting in a decrease in power consumption.

We propose an optimization approach to EoS (Ethernet over SDH) buffer control which the objective is to dynamically adjust the EoS buffer management registers. We will present the improved model of the traffic buffer management based on embedded MCU to control the SDRAM of the EoS chip, and setup the end-to-end system to illustrate the feasibility and advantage of the solution in buffer management when the data transport rate suddenly exceed the bandwidth of Ethernet port.

Low Density Parity Check code is more and more taken seriously in high-speed transmission. In this article we represent a LDPC coder and decoder which based on IEEE802.16e and realize the coder and decoder with Virtex-5 FPGA. By using Matlab to make an off-line system simulation, we analyzed and compared the LDPC performance under the different length of code for LDPC coder then analyzed the influence of different iteration to the LDPC BER performance of decoder.

Performance of coherent atmospheric optical communication system with heterodyne detection and LDPC codes was evaluated over atmospheric channel attenuations of which are about 20-30 dB/km. To reduce bit error and enhance the system performance LDPC code was implemented in system. Combining coherent detection and LDPC codes could reduce the received power requirement ~4 dBm at the BER of 10-9.

A coherent DPSK transmission system is presented to improve the receiver sensitivity for free space optical (FSO) communication. The coherent DPSK is an effective way to overcome the atmospheric turbulence. The eye diagram and bit error rate (BER) of the system are got by the simulation. Results show that with the coherent reception method, coherent DPSK offers improved signal-to-noise ratio (SNR) performance compared to the DPSK without coherent and OOK format. And hence it can be effective to overcome the signal impairment caused by atmospheric turbulence. It is shown that the sensitivity of the system employing coherent DPSK is 3dB better than a comparable system using DPSK without coherent and 9dB better than a system using OOK.

The performance of atmospheric communication system is limited by the atmospheric turbulence. In this paper, we present a practical 10Gbps DPSK transmission system for free space optical (FSO) communication with low error probability and wide-opening eye diagram. Compared to OOK modulation, DPSK format is a more effective way to resist the atmospheric turbulence. In addition, we designed parameters of this modulation system to be varied as the channel situation changed to achieve an optimized performance. The experiment results show that such a DPSK system could greatly overcome the atmospheric turbulence.

We propose a new automatic optical polarization demultiplexing method for NRZ-OOK and RZ-OOK polarization division multiplexed (PDM) system. The detected power differences of the radio frequency (RF) at low frequency are used as control signals which are sensitive to the angles between the states of polarization (SOP) of the polarization controller (PC) and the polarization beam splitter (PBS) at the demultiplexing side. The characteristics of the detected RF signals of NRZ-OOK and RZ-OOK are compared, and the best RF detection windows are calculated out through system simulation.

Dithering particle swarm optimization (DPSO) algorithm is introduced into adaptive polarization stabilization in a 40 Gb/s optical communication system. The DPSO algorithm has the merits of rapid convergence to the global optimum, without being trapped in local sub-optima, and good robustness to noise. How to implement DPSO as a component of a control algorithm in adaptive polarization stabilization is described. Performance comparisons between PSO and DPSO were carried out theoretically and experimentally. It is demonstrated that fast changes of SOP can be successfully tracked using the DPSO algorithm.

The scheme of adaptive polarization control with dithering particle swarm optimization (DPSO) algorithm is introduced in optical fiber communication system. The DPSO algorithm has the merits of rapid convergence to the global optimum, without being trapped in local sub-optima, and good robustness to noise. The performance of the DPSO of adaptive control algorithm is carried out theoretically and experimentally. It is demonstrated that fast changes of SOP can be successfully tracked using the scheme adaptive polarization control.

A novel all-optical label swapping based on optical return zero (RZ) differential quadrature phase shifted keying/inverse return zero amplitude shifted keying (RZ-DQPSK/IRZ-ASK) combined modulation format scheme is investigated and analyzed theoretically. Internet protocol (IP) packets can be efficiently labeled and processed using this proposed scheme. Numerical simulation is taken to demonstrate the transmission characteristic of the all-optical label swapping based on RZ-DQPSK/IRZ-ASK modulation format. The transmission performance can be affected by the duty cycle of the IRZ pulse, the IRZ-ASK label extinction ratio, the dispersion compensation ratio, received optical power and the coupling coefficient of the coupler. Results show that the IRZ-ASK label extinction ratio is almost infinite and preferable performance is obtained. The proposed scheme is a practical solution to meet the data rate and cost-efficient of the optical links simultaneously in tomorrow's all-optical label swapping.