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In this work, a novel triad nanocomposites containing trititanate nanotubes, Ag nanoparticles and dopamine were prepared and the SERS properties were measured experimentally. Control over the size and position of the Ag nanoparticles in the TiNT-dop-Ag system, along with the localised surface plasmon resonance (LSPR) of the Ag particles matching the Raman excitation wavelength, gives a SERS enhancement greater than 6 orders of magnitude. Electromagnetic modelling was used to provide a theoretical basis for these results.

In this paper, an intelligent wiper is designed base on STC89C51 Microcontroller. This intelligent wiper system can detect raindrops in real time with high sensitivity and automatically adjust the wiper speed according to the actual situation of rain. At the same time, the system can be manually switched by three wiper speeds: fast, medium and slow. The software system is based on the programming code and realizes the control of STC89C51 single chip microcomputer. In the whole measurement process, the system can work normally and respond to various instructions perfectly. After optimization and improvement, it finally shows a very high performance and fully meets the initial design requirements.

Routing protocols are perceived to be growing hotspots and required to devote more time and work to studying it. Research on routing protocols of wireless sensor networks is significantly important to accurately guide the application. Theoretical analysis and comparison are one of the key steps in the protocol research. Restricted by irreversible factors of power and others, lifetime of wireless sensor networks is very short. In this paper, we analyze and compare the characteristics and application fields of existing protocols. On the basis of that, this paper mainly proposes an improved directed diffusion exploring the phase of reinforcing path, which chooses the way to strengthen the path after evaluating the critical factors. It was determined by simulation that improved directed diffusion has a higher transmission rate, and it satisfies the requirements, which balancing the energy consumption and prolonging the lifetime.

A novel Cu2O-Au-BFO heterostructure photocathode was constructed which significantly improved the efficiency of photo-generated carrier transfer for solar hydrogen production. A BiFeO3 (BFO) ferroelectric film was synthesized on top of a Cu2O layer by a sputtering process. The BFO layer acted to protect the Cu2O layer from photochemical corrosion, increasing photoelectrochemical (PEC) stability. The p–n heterojunction between Cu2O and BFO layers enhanced the PEC properties by suppressing charge recombination and improved interfacial charge transfer efficiency. When Cu2O and BFO are interfaced by Au Nanoparticles (NPs) the PEC performance was further enhanced, due to hot-electron transfer at the plasmonic resonance. After positive poling, the depolarization field across the whole volume of BFO film drove electrons into the electrolyte solution, inducing a significant anodic shift, Vop of 1.01 V vs. RHE, together with a significantly enhanced photocurrent density of −91 μA/cm2 at 0 V vs. RHE under 100 mW/cm2 illumination. The mechanism was investigated through experimental and theoretivcal calculations.

In recent years, the city’s ecological environment construction and environmental protection work have made good progress. The ecological environment still have many weak links and problems in the construction of ecological environment. This article combines Suzhou’s achievements and experience in ecological environment construction of Caohu Lake, and analyzes Suzhou’s measures and achievements in ecological environment construction and environmental protection. Provide experience reference for the construction of ecological environment in other regions.

The requirement of the credibility is analyzed for smart grid data and the traditional theories of data measurement and bad data identification are studied in power system. On the basis of that, this paper mainly studies the credibility between data sources, the construction of the trusted network generation algorithm, and the hierarchical and dynamic trusted network model innovatively which is based on the relationship between data sources. The credibility evaluation of data sources, the credibility evaluation between data sources and the credibility evaluation of data are studied. The credibility between data sources is restricted by the credibility of data sources, the credibility of data sources is restricted both from the credibility of data and the credibility between data sources, the credibility of data is restricted by the credibility between data sources and the credibility of data sources, they are interrelated and restricted by each other and constitute to a whole. The simulation results show that the model can satisfy the requirement of the credibility of smart grid data better, and provide the ideas to solve the problem of the credibility measure for prospective research is feasible.

Pb(Zr(0.2)Ti(0.8))O3 wrapped CaFe2O4 particles were constructed on ITO coated quartz as a photocathode for efficient water splitting. A photocurrent of 152 μA cm(-2) was obtained under zero bias vs. Ag/AgCl and 100 mW cm(-2) with the assistance of positive poling and Ag decoration.

A growing body of evidence suggested that elapsing time is tightly associated with space in a specific way (e.g., Spatial Temporal Association of Response Codes or STARC effect). However, existing findings cannot justify a hypothesis that elapsing time is recoded directly into a spatial linear representation in working memory. The present study addresses this fundamental question by using three modified STARC-related working memory paradigms. In different experiments, participants were asked to give order judgment, order-irrelevant STM recognition judgment, or motor-related free-choice judgment, immediately after successive presentation of a set of disparate stimuli. Results show that responses to early stimuli were faster or more often with the left key and responses to late stimuli were faster or more often with the right key. These findings clearly support the hypothesis that elapsing time is directly and automatically recoded into a spatial linear representation in working memory.

Association rules are an important branch of data mining. Aiming at the update maintenance problem of association rules when increase the database data while keep the minimum support unchanged, on the basis of FUP algorithm, this paper proposes a matrix-based incremental association rules mining algorithm, namely MBFUP algorithm. The algorithm just scans the database once, and doesn't produce candidate item sets, greatly reduces the space complexity and time complexity of the algorithm.

The original mode becomes hard to meet the requirement of power communication resource management for the network environment with complex topology structure, with multi-vendor resource in it. Since management of power communication resource is faced with a variety of challenges, it is very meaningful to set up a suitable topology for the connection of power communication resource and visualize this topology in an optimized way. This paper firstly analyzes several classic layout algorithms for topology visualization and makes a comparison among these algorithms, and then selects a modified tree layout algorithm based on a spanning tree frame to visualize the network topology according to the characteristics of power communication resource management's network topology.

WAMS (Wide Area Measurement System) is an important part of smart grid, it is the basic effective methods to realize power system dynamic security monitoring, safety and reliability of its communication network become increasingly prominent. In this paper through the identification of risk analysis and risk factors of WAMS communication network, Established the WAMS communications network risk assessment index system. The integrated use of fuzzy analytic hierarchy process and the D-S evidence theory realized quantification of all levels of the index factors in the evaluation index system, And then could determine the risk value and risk level of the WAMS communication network, Realized the quantitative risk assessment of the WAMS communications network.

For efficient utilization of solar light during photoelectrochemical (PEC) water splitting, tandem photoelectrodes comprising a wider bandgap top semiconductor stacked above a smaller bandgap one have been proposed in the previous studies. However, the photocurrent is usually limited due to the blocked transfer of photogenerated carriers on the interface between the semiconductors. Here, this study constructs an Si-pnn+/ITO/Au/BiFeO3 (BFO) hybrid photocathode catalyzed by MoS2/Pt with an intension to fulfill the efficient transfer of photogenerated electrons from Si to electrode surface. This study reveals how the local surface plasmonic resonance effect of Au nanoparticles and the depolarization electric field of BFO enhance the PEC reactivity of the photocathode, and also the catalytic effect of the combined MoS2/Pt catalyst. Remarkably, the photocathode exhibits an onset potential of 1.3 V versus reversible hydrogen electrode (RHE), and the photocurrent at 0 V versus RHE can be up to –9.1 mA cm−2 under 100 mW cm−2 Xe-lamp illuminations. Such a unique design represents a general strategy to enhance the PEC performance of a tandem photoelectrode where the energy bands are not so matched on the interfaces, and therefore extends the scope of the tandem architectures.

The overall objective of the network security situation assessment is to establish security situation assessment system. This system can unify the large-scale network. First, it provides a security policy unified the whole network. It also provides the techniques for wide-area situation assessment. At the same time this system provides situational awareness and decision support tools for the implementation of network security command. Firstly, the information model of security situation was studied based on XML. Then the security situation value of system including three levels: service, host and network was analyzed and calculated. The-support vector regression machine was chosen for predicting the network security situation and determined the parameter values. Finally, the effectiveness of the method was verified through experimental analysis.

In order to effectively finish the dynamic risk assessment of the electricity system, this paper will divide each attack into three distinct phases, The difficulty of attack is assessed by percent of each attack time of distinct stages take up in the total attack time to describe the attack difficulty in order to determine the status of the assets transition matrix, realising the dynamic nature of risk assessment. The real-time dynamic risk assessment methods based on Hidden Markov Model HMM has a strong adaptability and scalability, it can be effectively applied on the network, host, system, service level of risk assessment. This paper designs and implements the dynamic risk assessment examples power system, and then demonstrateds the dynamic assessment model.

This paper introduces an improved PSO algorithm for power communication network routing, which minimizes the cost of communication and improves the Quality of Service (QoS). In this paper, PSO algorithm is improved in two parts of the parameter inertia weight and the discrete idea is added to, so that it can easily run out the local optimum and provide high speed of convergence as well as for the proposed application. An example shows the feasibleness and effectiveness of the algorithm. And it is easier to get an optimal or nearly optimal solution in power communication network routing by using the presented algorithm.

Hybrid intrusion detection is a novel kind of model combining the advantages of anomaly detection and misuse detection. We design a new hybrid intrusion system based on Principle Component Analysis and Self Organizing Maps, aiming at establishing an extensible real-time intrusion model with high detection accuracy. Experimental results on the KDD 1999 Cup dataset show that the proposed model is promising in terms of detection accuracy and computational efficiency, thus amenable for real-time intrusion detection.

In order to improve the accuracy of risk assessment of corporate networks, the paper introduces the concept of network shell into the field of security risk assessment. After analyzing the actual needs of corporate networks, we give the risk assessment model of network shell, then based on this model we analyze the application of network shell and give the algorithm to repair the network shell through the attack graph. After that, a calculation method of the integrated value of network shell is given. Finally, an example is given to verify the validity of assessment model.

Name agreement is the extent to which different people agree on a name for a particular picture. Previous studies have found that it takes longer to name low name agreement pictures than high name agreement pictures. To examine the effect of name agreement in the online process of picture naming, we compared event-related potentials (ERPs) recorded whilst 19 healthy, native English speakers silently named pictures which had either high or low name agreement. A series of ERP components was examined: P1 approximately 120 ms from picture onset, N1 around 170 ms, P2 around 220 ms, N2 around 290 ms, and P3 around 400 ms. Additionally, a late time window from 800 to 900 ms was considered. Name agreement had an early effect, starting at P1 and possibly resulting from uncertainty of picture identity, and continuing into N2, possibly resulting from alternative names for pictures. These results support the idea that name agreement affects two consecutive processes: first, object recognition, and second, lexical selection and/or phonological encoding. (C) 2010 Elsevier B.V. All rights reserved.

With the development of information technology and the popularization of the Internet, the amount of information based on the network has raised rapidly, and the emergence and development of network information filtering provide a better choice for people to access to the information quickly, accurately and completely. In this paper, the introduction of PSO uses its simple and efficient to establish accurate user model. It takes the access and update of profile as a process of learning, adjusted, learning again. Model is updated under considering inertia weight, parameters and other factors. Then doing some experiments test it.

In view of the characteristics and the special demands of the electric power information system, this paper designs an assessment model based on variable precision rough set. Then, it uses group decision-making theory, which could make the results of the assessment more accurate and more objective, to calculate the risk value of the target system risk. And then VPRS and AHP are used to determine the index weight involved in the process of the electric power information risk assessment. Finally, it verifies the correctness of the algorithm by analyzing results of the examples of the electric power information system security assessment. We can see that the model could not only find the weakness of the system by analyzing the results got by calculating the current risk value of the electric power system, but also reduce the influence of the subjective factors in some degree.

With the rapid development of computer network, the network is confronting a growing number of threats. Therefore, it is very important to assess the risks for the network information system. This paper draws data mining technology based on association rules into the field of risk assessment, demonstrating a network security risk assessment model based on association rules. The model mines data from history vulnerability database to discover association rules of vulnerabilities, and it is applied on risk assessment of vulnerabilities. In addition, the paper shows a multidimensional association rule mining algorithm based on improved Apriori, and it is proved that it is available by the experimental results.

Network traffic anomaly detection can be done through the self-similar analysis of network traffic. In this case, the abnormal condition of network can be indicated by investigating if the performance parameters of real time data locate at the acceptable ranges. A common method of estimating self-similar parameter is the Wavelet transform. However, the Wavelet transform fails to exclude the influence of non-stationary signal’s periodicity and trend term. In view of the fact that Hilbert-Huang Transform (HHT) has unique advantage on non-stationary signal treatment, in this paper, a refined self-similar parameter estimation algorithm is designed through the combination of wavelet analysis and Hilbert-Huang Transform and a set of experiments are run to verify the improvement in the accuracy of parameter estimation and network traffic anomaly detection.

For evaluation of the risk in information system, variable precision rough set (VPRS) theory is emerging as a powerful tool for reasoning about data. The method for risk rules mining in information system based on VPRS is designed on the basis of related concepts of VPRS. Through the example of the assessment, it is considered that the method can not only reduce greatly the data, but also increase the validity of risk regulations.

In accordance with the characteristics and the special demands of electric power information system, this paper designs a support vector machines (SVM) risk assessment method based on group decision-marking. According to security technology indices of electric power information system, the method chooses the mode of expert scoring, based on the group decision-marking, to calculate integrated value of each index, which is as a training sample used to train SVM, and it forecasts risk level for the system. Finally, it verifies the correctness of the method by analyzing results of the examples of the electric power information system security assessment. The experiment shows that the method can not only forecast the current risk level of the electric power system with a high accuracy rate, but also reduce the influence of the subjective factors in some degree.

This paper use the source of web log data and through AprioriAll algorithm among sequential pattern mining to identify the user pattern in the data pre-processing stage and based on pattern to cluster users’ path pattern and make the similarity users cluster one group in order to reduce pattern. Through testing, the method has been proven to be effective for users in personalized service.

In this article, introduced particle swarm optimization and multiply particle swarm optimization firstly, then modified BP neural network model through using multiply particle swarm optimization. According to above processes, the modified BP arithmetic was used in the Chinese word segmentation field. Applying BP network had achieved the prototype system of Chinese word segmentation. Based on PSO arithmetic, the prototype system made the network study training and used some samples of studying training to do some simulation experiments. The result of experiments expresses that the model of Chinese word segmentation’s ability obviously increased with the increasing training samples. So, the word segmentation that is proposed in this article is effective and has actual application value.