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Dissolved gas analysis (DGA) is an efficient method to diagnose faults of oil-immersed power transformer in the early stages. Tin oxide $(\mathrm {S}\mathrm {n}\mathrm {O}_{2})$ has been extensively studied as a gas sensing material since it is well known to be effective in sensitively detecting various gases. However, the sensitivity of gas sensor will be deteriorated seriously when the humidity of working detecting environment changes, which makes response curve fluctuate and drifts distinctively. As humidity has a huge impact on the detection accuracy, it becomes one of the most important considerations in the practical use of sensors. In this paper, three gas sensors based on $\mathrm {S}\mathrm {n}\mathrm {O}_{2}, \mathrm {P}\mathrm {d}/\mathrm {S}\mathrm {n}\mathrm {O}_{2}$ and $\mathrm {Z}\mathrm {n}/\mathrm {S}\mathrm {n}\mathrm {O}_{2}$ sensing materials were synthesized by hydrothermal method and characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDS). Meanwhile, the performance of the gas-sensing under different environmental humidity was tested. The results show that metal doped gas sensors are better sensitivity and stability than that of the pure $\mathrm {S}\mathrm {n}\mathrm {O}_{2}$ gas sensor. Moreover, with the increase of humidity the detection sensitivity of $\mathrm {P}\mathrm {d}/\mathrm {S}\mathrm {n}\mathrm {O}_{2}$ and $\mathrm {Z}\mathrm {n}/\mathrm {S}\mathrm {n}\mathrm {O}_{2}$ sensors emerge a phenomenon of increasing first and decreasing then. Ultimately, based on the sensing properties of pure, Pd and Zn-doped gas sensors, the possible sensing mechanism for them in humid atmosphere was investigated, which will make contribution to the application of $\mathrm {S}\mathrm {n}\mathrm {O}_{2}$-based gas sensors in the online monitoring of dissolved gases in transformer oil.

To meet control requirements and solve the problems in the control process of palletizing robot, a palletizing robot remote control system is designed. This system consists of the palletizing robot client and the server, focusing on the design and implementation of the client and the server communication protocol based on TCP / IP protocol. First, this paper defines the format and content of the data packet. Then it designs system structure, protocol function and communication process. The security is ensured by data encryption in the communication process. Finally, the validity and reliability of the protocol is verified via simulation experiments with some examples of the protocol code and algorithm flow chart. It is hoped that this paper lay a foundation for communication between palletizing robot servers and clients.

An event related potential (ERP) called feedback related negativity (FRN) is believed to encode reward prediction error (RPE) in the human brain. In this paper we conduct an experiment to study the influence of effort on the size of RPE through an investigation on the magnitude of the corresponding FRN. However, FRN is inevitably distorted by the neighboring P2 and P300 ERP components, and this makes the evaluation of FRN difficult. To resolve this issue, we apply blind source separation to decompose the ERP signal into isolated ERP components, adopting two-step temporal and spatial decompositions, using the Promax and information-maximization algorithms, respectively. Experimental results show that FRN can be reliably isolated and the influence of effort on RPE can then be evaluated.

This paper expresses the laser material processing technology used in quartz double-H gyroscope. This processing method can be used to depress mechanical coupling and change the frequency of gyroscope. The gold masses on gyroscope chip are made by micro-electroplating method. Then, nanosecond laser with 30 ns pulse duration and femtosecond laser with 50 fs pulse duration are used to process the gold masses respectively. Surface qualities of adjustment potions are compared and analyzed. The parameters of laser system are determined. Preliminary trimming with femotsecond laser for depressing mechanical coupling is done, and the quadrature error decreases by 92%, from 1.840 V to 0.143 V. The experimental results provide a basis for depressing mechanical coupling and tuning frequency in the future work.

There are several similarities between prospective memory (PM) and vigilance, the present study aimed to examine the relationship between PM and vigilance using event-related potentials (ERP). Behavioral results indicated that PM showed longer reaction time and less accuracy than vigilance. The ERP data revealed that PM and vigilance did not show significant difference during 200-400ms in occipital region, i.e., the cue detection process, vigilance evoked more parietal positivity (related to categorization and monitoring process) than PM, but it may be related to the difference of ongoing task and non-target trials, PM evoked more negative slow wave in frontal region, suggesting post-retrieval evaluations of PM.

A closed-form solution is presented in this paper for the prediction of stress field, strain field, support force and radius of plastic division in the rock mass subjected to axisymmetric loads around circular openings, which has an important role when dealing with the deformation of tunnel rock mass. The rock mass is assumed to be governed by three-parameter unified strength theory proposed by YU Maohong. Some important facts were considered, such as the in-situ 3D stress condition and the characteristic deformation of rock mass, the correct choice of strength theory which taking the intermediate principal stress into consideration. The results were found to be more practical and worthy of reference when the support design was performed.

On the basis of our realization to the world, granulation is one of the basis concepts. It refers to the whole divides into the parts. Information granulation has a key role in many methods and technical domains. The theory of fuzzy information granulation (TFIG) is elicited by man's information granulation method and based this to infer. Support vector machine (SVM) is an effective method to predict the time series. This article studies the prediction of surrounding rock deformation by using SVM method based on TFIG. Combining with a project case, the algorithm is realized by Matlab program. The results show that this new method can well and truly predict the bound of the next five day's displacement of surrounding rock.

A hybrid approach based on the pseudo-sequential sampling and the network-equivalence techniques is proposed for distribution system reliability evaluation in this paper. In pseudo- sequential sampling, a failure state is obtained based on the non- sequential simulation at first, then the whole system interruption I(a set of successive failure states) is acquired by the forward/backward simulation associated with the given failure state. The average failure rate of load points can be calculated easily by the mean value of the outage duration in all the interruptions. The calculation error introduced by the hybrid approach possibly caused by the network- equivalence is also analyzed in detail in this paper. Case studies on the IEEE RBTS test system are given and discussed, which validate the feasibility and effectiveness the proposed model for distribution system reliability evaluation.

Doubly-fed induction generators (DFIG) are widely used in the wind farms. Many papers focus on their behavior connecting to an infinite bus and the influence on the power system stability ignoring the grid side converters. In this paper, the dynamic simulation of doubly-fed induction generators on multi-machine power system is studied. With the decoupled active and reactive power control scheme, compensated terms of the rotor voltage control are used to simplify the solution of rotor currents, the relationship between PI control and the induction generators is illustrated. Under the wind disturbance, maximum power tracking during the mode change of the induction generators, i.e. from sub-synchronous mode to super-synchronous mode and the power contribution of rotor side converters under the mode change are shown. Under the grid fault, the PI controllers' contribution to the over-voltage of rotor side converters and the difference between active power of rotor side converters and grid side converters are investigated.

Through the functional analysis of vessel monitoring system (VMS), Design of VMS has been made. It includes ship-borne terminal device, shipping monitoring and control center, ship-shore communications. Use Advanced RISC Machines controller as the main controller of ship-borne terminals. Means of communication based on Inmarsat-C satellite system. In the offshore and river, to use public wireless communications as a supplement. This method can reduce communication costs. It is conducive to the promotion and applications of VMS.

One of the most important issues in the development and utilization of wind-based distribution generation is to quantify the impact of wind power on distribution system reliability. This paper proposes how to deal with wind generators connected to sub-feeders of distribution system in reliability evaluation by means of the network-equivalent approach. The random nature of wind power, which is quite different from the conventional substations generation can not be ignored in reliability assessment. In this paper, wind power uncertainty caused by wind speed is investigated by dividing wind speed into intervals described by the mean output and interval probability. Then load importance is studied by classifying loads into various grades, each with different weight coefficients. It is assumed that wind power supplies to customers on sub-feeders with wind generators within the limits of its random capacity judging by the load grades. The impacts of wind power capacity and different integration locations on distribution networks reliability are also researched. Reliability indices are calculated considering wind generation uncertainty and load importance, revealing the remarkable influence of wind power on distribution system reliability.

Urban gridding management model creates a new era of urban management. Scientific and rational division of the grid can carry truly out a new concept of urban governance: fining, gridding, information, humanization. Service GIS is a Service-Oriented Architecture (SOA) of the Component GIS. It brings the third generation of geographic information-sharing revolution which is data sharing and function sharing, but also successfully opens the era of geo-information services aggregation. Urban gridding management system based on service GIS mainly researches that the use of gridding technology and service GIS technology implement data resource of urban gridding integration and sharing under the SOA architecture, but also on urban management process eliminate emergency phenomenon of 'information silos' and 'information chimneys' and so on. The establishment of urban management mechanism which is collaborative management, operation efficiency, data and function sharing bring greatly out social and economic benefits of urban construction.

In order to solve the problems which digital mine is facing, a solution of digital mine based on grid GIS is put forward in this paper. Firstly, the paper systematically introduces the grid and its architecture, and the concept of grid GIS; then designs the digital mine system based on grid GIS. Digital mine construction is one of the important means to maintain the sustainable development of mining; grid GIS can provide effective technical support to it. Digital mine was introduced after the concept of the digital earth. A digital mine is set up on the basis of digitalization, informationization, virtualization and integration, and it is a unified system of management and controlling of computer network. It integrates various factors such as production, management, administration, environment, resources, and safety and benefits so that the enterprise can be developed harmoniously under the condition of "green" mining to improve the competitive ability and adaptability of coal enterprises

The significance of developing community GIS (Geographic Information System) is put forward and a brief introduction which is related to the characters of COM (Component Object Model) is given. The key technology of database design under the component technology is researched. The function of the system, the design and realization of the model are introduced.