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In this paper, the heat transfer performance and flow resistance characteristics of the asymmetric arrangement of the rectangular winglet longitudinal vortex generators in the rectangular channels are numerically studied. Results show that at Re=500~2000, comparing with the symmetric arrangement of the longitudinal vortex generator, the Nusselt number of the asymmetric arrangement of the longitudinal vortex generator only decreased by 4% ~ 6%,while,the friction factor f decreases by 11% ~ 22%,the effect of flow drag reduction is very obvious. The asymmetric arrangements of the longitudinal vortex generators show the better overall thermal performance with the increase of j/f by 5% ~ 20%.

Present icing monitoring system mainly depends on detecting the meteorological parameters and dynamic characteristics of the structure of the overhead icing line. However, all these systems need additional equipments for data collection. This paper provides a new method based on voltage and current of both ends of the line and discriminates the icing region and its severity via the change of active power and reactive power. It requires the voltage and current serving as signal source which is provided by the data collecting device on the both ends of lines. In this way it can accomplish the Monitoring task of icing transmission.

In this paper, a Fault Tolerant Control (FTC) strategy for Linear Parameter Varying (LPV) systems is proposed. The main idea of this FTC method is to transform the actuator fault to varying parameter such that an active FTC controller can be designed with gain-scheduled H∞ control approach. The resulting controller is a function of the fault-effect factor which reflects the actuator fault and can be estimated on-line. The effectiveness and performance of the proposed approach are illustrated by a two-link manipulator.

According to the research of VANET routing protocol, an improved protocol SN-GPSR has been proposed. It is based on the sensitive nodes. The nodes select routing through a special position and steady speed under GPSR protocol. In a crossroads scenario, we designed a vehicular mobility model and simulated it using NS-2. By analyzing the results, the network performance parameters of SN-GPSR have improved above the GPSR, such as delay, packet loss and others.

The effects of synthesized silver nanoparticles on electrospun PHBV ultrafine fibers were studied by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA). Addition of silver nanoparticles increased from 0.1% to 2.0%, the sooth ultrafine fiber with an average diameter of about 2 μm formed a non-woven mat was obtained. DSC showed the efficient heterogeneous nucleation by the silver nanoparticles for facilitating PHBV crystallization.The thermal stability of the PHBV/Ag ultrafine fibers improved with the increase in the content of the silver nanoparticles.

A PID temperature control system was designed with the LabVIEW graphical programming language and the PID toolkit. Data collection, PID control, data record and data check were experimented to a practicable instrument with the purchased programming power supply and data collection record system. The hardware and software of the computer with the virtual instrument system was proofed to be practical and the smooth control of the system temperature with the accuracy of 1 was available.

For the data is fuzziness and the uncertainty on software quality evaluation,on the basis of ISO 9126 quality model,an evaluation model of software quality is established based on fuzzy comprehensive evaluation and analytic hierarchy process in this paper.Through the establishment of software quality evaluation model, we can solve the multi-index evaluation problems of software quality effectively and it can be used to guide users to improve software process.

With the explosive growth of data, the performance of querying the huge amounts of data is more and more important.Simply Method of improving the performance of stand-alone already can't meet the demand.We need to handle huge amounts of data with distributed technology.However, traditional ways are just outrageous abuse of distributed resources, there are a lot of methods to improve efficiency and throughput.In terms of saving resources effectively, index is an indispensable tool.This article embarks from the traditional indexing mechanism, based on the advantage of the traditional methods in combination with the advantages of bitmap index, put forward a kind of extended local index mechanism,which is effective in reducing the traditional local indexes for distributed resources unnecessary overhead.At the same time it also improve the query efficiency. Finally, the test results show that the improved algorithm is efficient.

MESIS, a new generation system, based on advanced information technologies, such as geographic information, database, visualizing, workflow, multimedia and web, work for real-time analysis and mass-industrialization of metrology service products. The system has been installed and localized in Chongqing and the three class data is collected and got. The individualization maps are made with meteorology stations, rivers and administrative area and the models of meteorological service products are made. The meteorological service products can be produced automatically with MSPGS and the meteorological service products for a certain range can be got.

According to the characteristics of Ad Hoc networks, distributed intrusion response mobile firewall system is designed based on mobile Agent. Surveillance agent monitors neighbors communication behavior, and reports to the control agent. Control agent is in charge of judging, and activates tracing agent and blocking agent. Defensive agent is set up in system to keep the firewall mobile features. Depending on semi-Markov process (SMP) theory, we have created a dynamic behavior model of the mobile firewall system and analyze the performance of network security.

Application-layer distributed denials of service (DDoS) attacks are becoming ever more challenging to internet service security, since firewall and intrusion detection system work on network layer while these attacks are launched on application layer. In contrast to prior work focusing on detection of high-rate DDoS attacks at static web sites, we propose a novel approach to detect low-rate application-layer DDoS attacks at dynamic web sites. A feature matrix is introduced to characterize user browsing behavior. Principal component analysis (PCA) is applied to profile the user browsing behavior pattern. Outliers from this pattern are used to identify anomaly users. Experiments are conducted to validate our approach. Experimental results show that our approach is accurate to detect low-rate application-layer DDoS attacks.

According to the problem that the whole data and information is always necessary, using rough set theory as a guide, making some analyses on reduction in knowledge base and information system, this paper propose a general mode structure of reduction. It shows that there are three terms in process of reduction and the most important term is definition and measure of ability.

CdMnTe is one of the key materials for room temperature X-ray and gamma-ray detectors on Environmental Analysis and Monitoring. In this paper, the homogeneous Cd1-xMnxTe (x = 0.1) single crystal ingot was grown by the vertical Bridgman method. The compositional analysis was carried out by SEM/EDS. The Te inclusions were revealed by the IR transmission spectra. In dopant distribution was determined by ICP-AES measurement. The resistivity of CdMnTe was cha-racterized by I-V method. It was found that the segregation coefficient of Mn was 0.97. In dopant contents within 3 to 21 ppm of the ingot were found. The Te inclusions were mainly 8.2-28.3m in size and 1×105-1.5×107cm-3in concentration. I–V measurement reveals that sputtered Au film can form good ohmic contact and all the slices have the resistivity within 107 to 109Ωcm.

The performance of optical wireless communication (OWC) links based on the spectral amplitude encoding (SAE) of a broad-band spatially partially coherent beam through atmospheric turbulence is analyzed. It has been found that the power efficiency of transmitters of OWC links based on the non-uniform SAE is higher than that based on the uniform SAE. Further, the spectrum division method for the non-uniform SAE of broad-band beams has been proposed. The non-uniform SAE of a broad-band spatially partially coherent beam is an effective method to reduce the performance degradation of OWC links caused by atmospheric turbulence.

People recognized the importance of communication from Wenchuan earthquake in 2008, which could help rescue team to protect the life and property of the people without delay, at the same time reduce the loss caused by earthquake. According to the feature of emergence rescue in earthquake and requirement on communication of fire army, this paper set forth the application standards and modes of wireless communicating technology in the scene of earthquake rescue, which included wireless short-wave and satellite communication.

Polycrystalline ZnO thin films codoped with Cu and N have been obtained by chemical bath deposition. The effect of N incorporation and Cu-N incorporation on microstructure and optical properties of ZnO films has been investigated. X-ray diffraction patterns of the films indicated N incorporation deteriorated the crystalline quality while Cu-N incorporation improved the crystalline quality. The PL spectra showed that the relative intensity between the ultraviolet luminescence and the deep level-center luminescence of ZnO thin films was clearly correlated with the crystalline quality. Furthermore, the Raman spectra revealed the intensity of E2 (high) increase with Cu-N incorporation.

This paper constructed a model to propose the financial crisis impact on inbound tourism. Two hypotheses are about the relationship between financial crisis and the number of inbound tourist, plus inbound tourists’ expense. This paper analyzes the number of inbound tourists and their average expenses by TRAMO/SEATS and Eviews software under the influences of financial crisis. The results show that firstly foreign exchange earnings, inbound tourist number and average expense have been reduced obviously. Secondly, the influence on average expenses is less than that on inbound tourist numbers at the end of 2008. The recovery of average expenses was faster than that of tourist numbers. Thirdly, the influence of inbound tourist numbers is greater and longer than that of average expenses. Fourthly, time length and degrees of crisis are quite different when trend curves are various. Then the paper puts forward specific countermeasures with Chinese characteristics.