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For the spread spectrum communication system with ultra-low bit rate, the convolutional code and the spread spectrum system are cascaded to improve the performance. Based on the high computational complexity of traditional orthogonal convolutional codes, the system uses fast Walsh transform optimization to speed up the decoding speed and tail biting mechanism to improve the transmission efficiency. The results show that the bit error rate (BER) performance is improved as the increasing of the constraint length. When the constraint length is 10 relative to 5, the demodulation gain is 2.5dB at the BER of 10-4; Compared with the direct sequence spread spectrum system, when the orthogonal convolutional code length is 8, the demodulation gains are 3.5dB, 4.75dB, and 5.5dB at the BER of 10-2, 10-3, and 10-5.

Precise wind speed prediction is increasingly practical for sustained and stable wind energy utilization considering the growing portion of wind energy in the global electric grid. Although plenty of wind speed forecasting approaches have been devoted to improving forecasting performance, the majority have neglected the utilization of error information, integrated the forecasting value of every component with simple ensemble approaches, and ignored forecasting stability, which may make the forecasting results poor. Considering the above drawbacks, a two-stage forecasting system is performed in our study based on the data preprocessing approach, improved multi-objective optimization algorithm, error correction and nonlinear ensemble strategy. The developed system effectively overcomes the shortcomings of previous models and observably prompts wind speed forecasting capacity. For investigating the prediction capacity of the developed system, six wind speed series obtained from China and Spain are applied as case sites. The forecasting consequences indicate that the developed system is more conducive to enhancing forecasting precision and stability than other involved models, which can provide beneficial assistance for wind speed forecasting.

This paper presents a circularly polarized magnetoelectric (ME) dipole leaky wave antenna (L W A). The proposed antenna characterizes its broadside radiation and contains circular polarization when beam scans from backward to forward as frequency increases. Substrate Integrated Waveguide (SIW) is employed as the basic transmission line to guide electromagnetic waves. Impedance matching technique is adopted to eliminate the open-stopband (OSB) effect, which produces a discontinuity for a seamless L W A. A ME dipole layer is added to realize circular polarization (CP). Simulations demonstrate that the scanning range of the proposed antenna is from −12° to +12° and the axial ratio (AR) is below 3dB between 21GHz and 26GHz.

By representing data through compact binary encodings, hashing techniques have been widely used for data retrieval because of their large data storage and efficient computational time. Most hashing algorithms typically learn a finite number of data projections, but learning optimal projections remains unaddressed. To deal with this limitation, a novel approach, dubbed Adaptive Hashing with Sparse Modification(AHSM), is proposed that learns binary indices composed of the vertices of hypercube and the projection matrix are comprised of two matrices in this paper. The first matrix is orthogonal for rotating data and the second one is sparse for modifying data. The essence of our scheme is that an optimal transformation of data is learned to minimize quantization distortion and improve model fidelity. AHSM has two contributions: the first one is accuracy improvement, and the second one is no increase on computational complexity. Through experiments, we find that AHSM substantially surpasses several state-of-the-art hashing schemes on three data sets.

While sparse representation is heavily emphasized in many recent literatures, the importance of collaborative representation is usually ignored. In this paper, we exploit the advantage of collaborative representation and propose a maximum entropy regularized group collaborative representation (MECR) algorithm for face recognition. MECR takes the group structure of the face data into consideration under the framework of collaborative representation, and uses maximum entropy principle to obtain discriminative coding for classification. Experiments show that MECR outperforms several state-of-the-art coding methods and dictionary learning methods on some benchmark face databases.

Aiming at resolving the problem of Class of Service (CoS) and traffic grooming, a CoS-enabled path selection algorithm with traffic grooming function (CPSATG) is proposed in this paper. Simulations are conducted to compare the proposed scheme with methods which have not considered CoS and traffic redundancy. Results show that CPSATG has a much better blocking probability performance and effective resource utilization than the existing methods with almost the same cost of network nodes.

For the Destination Initialed Reservation (DIR) in Wavelength Switched Optical Networks (WSONs) using the distributed wavelength assignment scheme, the establishment of a lightpath might be blocked because of the contention for the same lambda between two or more concurrent requests traversing the same links, although there might be enough available lambda resource. In order to reduce the blocking caused by contention, a Dynamic Backup-reservation-based Wavelength Assignment (DBWA) scheme has been proposed in this paper. Considering that it is not an advisable way to reserve additional wavelength when the resource is lacking and that a lightpath with more physical hops has the higher probability to collide with others, a threshold which refers to the number of available lambdas and the physical hops for a lightpath, is defined to decide whether to reserve a backup wavelength or not. Simulation results show that, by setting a proper value for the threshold, DBWA can reduce the blockings caused by contention efficiently thus performs much better in total blocking probability than the two traditional schemes.

This paper proposes a method to reduce the overheads of routing protocol by balancing network performance parameters in GMPLS network. When the traffic load is light, LSAs advertise traditional IGP weight for the link, but on the condition that the traffic load is heavy, LSAs advertise weight according to the occupied wavelengths of the links. After amending the weighting function of the link, we successfully reduce the number of TE-LSA while the network performance is still acceptable. Finally, we have simulated the proposed scheme.

A PCE-based congestion avoidance (CA) and Virtual Network Topologies (VNT) reconfiguration (CA-VNTR) routing scheme is proposed and detailed algorithm of CA-VNTR is provided. Simulations are conducted to compare the proposed scheme with traditional routing method in terms of blocking probability and resource utility. Results show that CA-VNTR outperforms traditional routing method in blocking probability, especially under heavy traffic load.

Study of incentive mechanism is always frontier and hot topic in economics. In student education and management work of independent institute, a variety of incentive mechanism also need be applied to stimulate student's study enthusiasm and cultivate the all-round development human, according to the students' actual features.

The mechanical properties of rocks can be continuously calculated with the help of theory of elastic mechanics and logging data (AC-sonic log, DEN-density log, CN-neutron log). A GIS administration system will be very helpful in running these data. This system applies the client/middle tier/server framework. It is composed of database, data access engine, purview control middleware and clients. Drawing layers are the basic spatial data unit. The 3D distribution of mechanical properties of rocks can be achieved underground by GIS visualization modules.

The biosorption of reactive red on acid-treated Penicilium sp. was investigated in a packed-bed column. The column experiments were conducted to study the effect of operating parameters such as initial dye concentration, adsorbent dose and flow rate on the column removal capacity. The Thomas model was used to analyze the experimental data. Column experiments showed that the fungal mycelia mixed with quartz sand possessed higher biosorption capacity than the biomass immobilized by sodium alginate. Column studies indicated that biosorbent dosage, dye concentration and flow rate affected the biosorption characteristics of Penicilium sp., with highest biosorbent dosage, highest dye concentration and lowest flow rate resulted in better dye uptake. At initial reactive red concentration of 200mg/L, flow rate of 0.06 L/h, amount of adsorbent of 5g (wet weight) and initial pH of 3, the biosorption capacity and rate of dye removal were 150.95mg/L and 64.84%, respectively. The column was successfully eluted using 0.01M NaOH, with an elution efficiency of 94.58%. The Thomas model could well describe the breakthrough data from column experiments. The results indicate that the Penicilium sp. could be used as a promising biosorbent for color removing.

The ability of Mg-Fe layered double hydroxide to remove C. I. Reactive Red 2 from aqueous solution was investigated. The influence of molar ratio of Mg-Fe, solution pH, contact time and initial dye concentration on adsorption capacity of C. I. Reactive Red 2 was studied. Batch isotherm studies were carried out on a laboratory scale to evaluate the adsorption capacity of Mg-Fe layered double hydroxide. The maximum dye removal was observed at Mg-Fe molar ratio of 4. Solution pH ranging from 2–8 had little effect on adsorption rate. The Langmuir and Freundlich isotherm models were used for modeling the adsorption equilibrium. It was obtained that the adsorption equilibrium data were fitted very well to the Langmuir as well as to the Freundlich adsorption model. The maximum dye uptake obtained from the Langmuir model at temperature of 30°C was 161.29 mg/g (R2=0.9965). The results indicate that Mg-Fe layered double hydroxide is a promising sorbent for dye removal from wastewater.

Based on the depth, efficiency of financial development and the scale of securities market, through the Unit Root Test, Co-integration Test and Granger Causality Test methods, we analyzed the causality between financial development and economic growth of Fujian Province during the period from 1978 to 2008. We find out that there is a bidirectional causality between the depth of financial development and economic growth. The efficiency of financial development is the cause of economic growth, but economic growth has no effect on the efficiency of financial development. There is no Granger causality between securities market and economic growth. In the end, we give some policy advices so as to improve financial development and accelerate economic growth.

In order to solve the wavelength resource reserve collision problem in distributed wavelength assignment senario for PCE/GMPLS-based WSONs, a half-centralized wavelength assignment scheme has been proposed, which efficiently avoids the collision by adding several functions to PCE and does some extensions to the GMPLS signaling.

Proposed in this paper is a PCE-Assistant Collision-Avoiding Wavelength Assignment Scheme (PACAWAS) for transparent Wavelength Switched Optical Networks (WSONs) to solve the resource contention problem in distributed wavelength assignment scenario. In this scheme, several extensions are made to the GMPLS (Generalized Multi Protocol Label Switching) signaling, and a wavelength selection assistant unit (WSAU) is added to the Path Communication Element (PCE) to which the destination node would resort when making a wavelength selection decision. Simulation results show that the proposed scheme is able to avoid efficiently the collisions of wavelength resource reservation and thus performs better in decreasing total blocking probability than the traditional ones do under different traffic scenarios.

As the economic system gets more interconnected and complex, the conventional economics based on diminishing returns and negative feedbacks are facing tremendous challenges. Multiple-equilibria, lock-in and inefficient path dependence are often witnessed. This paper aims to study the network economic system with non-linear positive feedback from theory to application. Starting from the concept of networks and network effects, it extends to the causes and consequences of positive feedback in network economy and the market structure transformation in specific. With the global web server market as an empirical example, we also prove the existence of positive feedbacks in reality.

It is well known that economy has developed rapidly in Eastern China since the reform and opening up, while the quality of eco-environment is becoming worse and worse. In the presented contribution, the speed and rationality of the urban growth in Suzhou city at various stages were studied, using the data of Landsat TM satellite images in 1995, 2000 and 2005. Moreover, the ecological footprint and the ecological capacity factors were introduced to investigate the relationship between supply and demand of the eco-environment resources in Suzhou city, and the ecological deficit was calculated to evaluate the quality of ecological-environment in Suzhou from 1995 to 2005. The analytical results indicate that the urban growth in Suzhou has a remarkable trend of increase from 2000 to 2005, with a speed nearly four times of that in the stage of 1995 to 2000. Meanwhile, the ecological deficit was increasing during the last decade, representing a continuously degenerated ecoenvironment with the rapid urban growth.

This paper aims to study the impact of network effects on the market structure of network industries. It starts from the concept of "network effects" and then extends to a simplified model of market structure and the empirical test of China's Internet industries. It draws the conclusion that the market structure of network industries with strong network effects tends to be more concentrated and monopolistic compared to industries without network effects.

This paper aims to study the lock-in strategy adopted by firms in network industries from the perspective of network effects. By introducing the network effects theory and corresponding lock-in model, it studies the rationale and practicality of lock-in strategy in network industries. Using Tencent QQ as an example, the theoretical conclusion of lock-in is applied in specific case study. It concludes that the lock-in strategy is not only feasible in theory, but also works well in reality.

Against the backdrop of widespread networks in the modern world, this paper aims to study the transformation of network economic system in general and its market structure in specific. It is organized in the mode of "concept introduction-model setup-empirical study". Starting from the concept of "network effects", it is then extended to a simplified model of market structure and the empirical test of global web server market. It is proved theoretically and empirically, that the natural market structure in network economic system tends to be more concentrated and monopolistic, which can hardly be explained merely by misconducts of market players as the conventional wisdom suggested.

With the progress of technology, intellectual property protection has evolved from a pure public policy to a combination of technical means and policy measures. The existence of network effects makes the issue even more complicated. Through mathematical and analytical tools, this paper seeks to analyze the optimal level of intellectual property protection in presence of network effects. Overall, it addresses two questions. What is the optimal technical protection level of an individual firm who maximizes its profit? What is the socially optimal protection level from the perspective of policymakers, who shoulder the obligations of stimulating innovation and technological progress? It is found that the optimal level is affected by a variety of factors and cannot be simplified as "the strong, the better".

In our experiments a normal gate FED was fabricated by screen printing method, obtaining the spot size and brightness uniformity on the screen in the vacuum chamber. Then we measured the dielectric layer's thickness. From the measurement results, the fluctuation of the dielectric layer is found. A simulation model is also constructed to analyze the sensitivity of the thickness of the dielectric layer on the brightness uniformity.

Hopping field emission display (HopFED) which is based on secondary electron emission is a novel structure of field emission display [1]. Compared to the conventional structures, this new type has several advantages. The brightness, the luminance uniformity and the profile of the spot on the screen have been improved. To simplify the fabrication process, the gate electrode is deposited on the bottom surface of the hop glass plate, as shown in Fig.1. However, a few electrons may be collected by the gate electrode in this structure.

Summary form only given. Recently, the carbon nanotube field emission display has drawn more and more concern. With its excellent image display quality and low fabrication expense, the printable CNT-FED will take the place of cathode ray tube as the major consumer-priced and mass-market display. A normal CNT-FED device is composed of the CNT cathode, the gate electrode, the anode and dielectric insulator layers. The gate electrode in CNT-FED is used to modulate and address the electron beam. Because some electrons may be collected by the gate electrode in a triode, the brightness of the image is decreased. This paper proposes a novel gate structure fabricated on a glass plate with diabolo funnels. Chemical corrosion was utilized to produce diabolo funnels in the glass dielectric layer and HF with the 40% concentration with sulfuric acid is used. A metal layer was screen-printed on the lower surface of the glass-mesh plate as an electron extraction gate electrode. MgO film was vaporized on the surface of the diabolo funnels. The electrons from CNT are transported in a diabolo mode via secondary electron emission over the wall of the diabolo funnel placed above the sub emitters. As a result, many electrons including the secondary electrons and backscatters are generated and the brightness of the diabolo mode gate structure CNT-FED could increase obviously. In the paper, we give the results of numerical simulation of the secondary electron emission process with Monte Carlo method. In this paper, we also study the influence of a MgO layer on the surface of the diabolo funnel. Comparisons are made between a bare glass diabolo funnel and a MgO layer coated on the surface of the funnel. As the simulation results and experiment results shown, the triode structure in which a MgO layer is vaporized on the surface of the funnel can get higher brightness