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When the service life of bridge structure ends, it must be removed. Blasting demolition method is a common method in bridge demolition engineering, and a reasonable blasting plan is essential to safely achieve the goal of bridge blasting demolition. By summarizing and analyzing related research results and engineering practice experience, the design content and method of bridge blasting demolition scheme were studied. The design content of bridge blasting demolition scheme mainly includes blasting position design, network design, parameter design and safety protection design. In practical operation, some design work can be carried out by referring to simple theory, while some design work needs to be carried out by referring to relevant engineering experience.

The system estimation by least squares optimization is employed to obtain physical polarization parameters of optical devices. The method is proved flexible and convenient for measuring polarization parameters in different systems where the input state of polarization (SOP) of the devices is either measurable or not, providing the analytical estimation equations and adequate measurements are available. The estimation error for the measurement system with a rotating wave-plate (WP) as the polarization state generator is analyzed and simulated. Better estimation precision can be obtained by involving more SOP measurements in estimations and choosing a WP with retardance around 3/4. Two experiments are demonstrated. One is to estimate the polarization parameters of a fiber polarization controller with measurable input SOP, and the other is to measure the retardance of a glass quarter-wave plate whose input SOP is immeasurable. The standard deviations of estimated polarization parameters are within 0.0011–0.0103.

In this paper, by introducing a current-controlled current amplifier with multi-outputs (MO-CCCA), two new multi-input and single-output (MISO) universal filtering circuits are proposed. Each circuit just contains two second-generation current conveyors with multiple outputs (MOCCIIs), one MO-CCCA and four grounded RC elements. They can realize low-pass, band-pass, high-pass, band-stop and all-pass filtering outputs. The characteristic parameters natural frequency ( ω 0 ) and quality factor ( Q ) can be tuned independently by bias current of MO-CCCA. Compared to other similar circuits, the circuits in this paper have simpler structures and independent tuning characteristics of ω 0 and Q. Moreover, a filter with a high Q can be obtained by adjusting the ratio of MO-CCCA's bias currents.

For visualization and contrast of IR images are weak, this paper proposed a novel image fusion algorithm for infrared and visible images based on object extraction via grey theory. Firstly, the grey correlation theory is applied to the infrared image for target extract; and then acquire the final object directly from the infrared source image. Finally, the image fusion quality is evaluated. Compared with four commonly used methods, the results show that the fusion image has a good visual effect, and some objective evaluation indexes are improved obviously. Its fused image can effectively preserve the detail of visible image and object information of infrared image.

This paper introduces architectures of two types optical packet-switched metropolitan area networks and their media access control protocols. We have designed related network simulation systems. With these simulation systems, the characteristics and performance of the two MANs can be achieved.

In this paper, a rolling ultra-short term wind power prediction (WPP) based on an online sequential extreme learning machine (OS-ELM) algorithm is presented. Two issues are specially considered to improve the wind power forecasting effect: wind speed sequence correction and error interval evaluation. Three independent OS-ELM based neural networks are accordingly designed: the single wind turbine generator model, the wind speed correction model and the error interval evaluation model, in which the OS-ELM's fast learning speed characteristics are well utilized. Case studies on a real off-shore wind farm in China with two years' history data prepared are performed to verify the effectiveness of the proposed method.

Massive increase in the proportion of large-scale wind power integration influences the transient security and stability of power system in a way that wind power tripping is needed under some severe fault circumstances. In this article, we analyzed the doubly-fed induction generator (DFIG) operational characteristics. Furthermore, the differences between thermal power and wind power tripping effects are examined from the perspective of transient energy. The results show that the combination of the wind power and thermal power tripping should be considered in the emergency control of the grid-connected wind farms system. Therefore, we proposed the optimal tripping decision-making considering wind turbine. The results of transient tripping example of a certain regional system show that selecting a reasonable tripping ratio of thermal power to wind power can improve recovery characteristics of post-fault system and improve the system's security and stability.

China has been using production-based VAT for a long time, while most countries in the world using consumption-based VAT. Compared with production-type VAT, consumption-based VAT has many advantages, such as stimulating investment, reducing the burden of enterprises. In addition, production-type VAT has not suited to China’s economic development. In September 2004, the State Council required the implementation of VAT reform in Northeast China, allowing companies in some sectors offset contained in the device class of fixed assets input tax. This paper analyzes the impact of VAT transformation reform of listed companies. In theory, the transformation of VAT directly affects the company’s recorded value of fixed assets and depreciation. And it can increase corporate profits, net profits. In order to test the impact of VAT transformation, this paper put forward two hypotheses: first, VAT transformation will stimulate investment; Second, value-added tax transformation will increase profit of listed company. This paper selects 2001-2003 and 2005-2008 financial data of 56 listed companies in Northeast China as the sample data, through the establishment of models, multiple linear regressions to test the value-added tax and profits, the empirical results show that the value-added tax has a positive role in the enterprise, improve the business performance.

A novel EoC (Ethernet over Coax) approach, called ECAN (Ethernet over Coaxial Access Network) is presented in the paper. ECAN is specially designed for the last 100-meter access over coax rather than an adoption from the home network solutions. ECAN employs MPCP (Multipoint Control Protocol) in the media access control layer and uses the single-carrier n-VSB (Vestigial Sideband) modulation in the low frequency band for the bidirectional communication. The basic concept, the implementation architecture and the tested system performances are presented in the paper. It is shown that ECAN can work in different scenarios and provide >100Mbps or up to 130Mbps throughput out of the 160Mbps physical level bit-rate. This proves that ECAN has efficient bandwidth utility, high cost-effectivity and high practicality.

In this paper we present a novel access strategy for bidirectional CATV network which uses the existing and widespread coax distribution infrastructure to provide high speed and cost-effective multi-service access. This system adopts IEEE802.3ah as Media Access Control (MAC) protocol, just as the same as that of EPON over the P2MP coaxial networks, so that it is with the feature of seamless connection with EPON, passing the Ethernet date to subscribers over coaxial networks. Besides PHY of the system is separated with MAC layer, therefore different PHY layer can be applied to build up the EOC system for various customer groups. And experimental results are presented at the end of the paper to demonstrate the favourable performance of the proposed system.

The cascaded fiber ring depolarizer is proposed for the purpose of reducing polarization effects in fiber communication and interference sensor systems. Using recirculating loops, countless light components deposed by arbitrary round trips could finally be of random state of polarization (SOP) and mutually incoherent at the output by proper arrangement of lengths of fiber rings, so that the degree of polarization (DOP) approaches zero statistically. In this paper, the depolarization mechanism and key factors of cascaded fiber ring depolarizer are analyzed and discussed, and the performance is measured experimentally. Experiment result proves that optimized 10-fiber-ring depolarizers can work for a light with bandwidth of 1.6 nm and gain a stable SOP-independent DOP of less than 2%.

A novel routing method called wavelength-separating in DWDM optical packet switching nodes for two-class priority traffic is proposed. Analysis of the method and a previous buffer-sharing method with special contention control are presented. The optimized results of two methods show that the wavelength-separating method performs better in reducing the packet loss rate (PLR) than the latter in case of with full wavelength conversion and small output buffer length.

This paper presents a novel differential current mode readout circuit for the ion sensitive field effect transistor (ISFET) as a pH sensor. It uses two second generation current conveyers (CCII), and provides an output current that is linearly sensitive to pH over a wide range (pH 2-12). It is more suitable for A/D conversion compared to voltage output circuits. The circuit is operating in differential mode, reference field effect transistor (REFET) is used to realize temperature compensation. The proposed readout circuit has simple structure, it uses only one type of active element (i.e. CCII), so that, it can be easy integrated on one chip and fabricated using a conventional CMOS process. Simulation results demonstrate the proposed circuit is well working and can be suitable used as an ISFET pH sensor readout circuit.

This paper presents a merged LNA and mixer covering the frequency range from 3.1-10.6 GHz that able to meet the UWB communication technology. By employing the capacitive cross-coupling transconductor, the gm is boosted and the NF is reduced. A current-mode mixer shares the output load of the LNA to achieve high gain and wideband matching simultaneously.The output current of LNA flows into the mixer directly, resulting in significant linearity improvements and power saves. Designed in the chartered 0.18-mum RFCMOS technology, this proposed block achieves the maximum power conversion gain of 16 dB and input reflection coefficient (Sll) of less than -10 dB from 3.1 to 10.6 GHz.The minimum single side band noise figure is 7.4 dB.An IIP3 is -4 dBm at 5 GHz.The power dissipation is 13.6 mW from a 1.5-V supply voltage.

A new lower complexity ultra-wide-band 1-10-GHz low-noise amplifier is presented in this paper. This LNA only consists of two simple amplifiers with an inter-stage inductor connected. The first stage is a common-gate amplifier that is used to attain the wideband input matching and low noise. A common-source amplifier with shunt-peaked load as the second stage achieves high gain and wideband output matching simultaneously that does not need the source follower. Designed in the TSMC 0.18 mum RFCMOS technology, this proposed UWB LNA achieves the maximum power gain (S21) of 12.1 dB with the 3-dB band from 1 to 10 GHz and input/output reflection coefficient (S11 ,S22) of less than -10 dB from 1 to 10 GHz.The minimum noise figure is 3.8 dB.An IIP3 is -4.1 dBm at 5 GHz.The power dissipation is 12.6 mW from a 1.5-V supply voltage.

The SOP evolutions induced by the nonlinear polarization modulation (PolM), including self-PolM (SPolM) and Cross-PolM (XPolM) of SOA's, are investigated in terms of the polarization evolution traces on the Poincare sphere by simulation. Such that the PolM effects of SOA's can be comprehended precisely. And the PolM effects influenced by the SOA injection current is simulated and discussed as well.

Two new CMOS realization circuits of current-controlled second generation current conveyor (CMOS CCCII) based on compound MOS translinear loop and MOS current mirrors is proposed. The circuit can satisfy port characteristic without need for restriction conditions which relate to fabrication parameters, so the difficulties of design and fabrication can be decreased. It presents such advantages as easy realization in the fabrication, simple circuit configuration, wide bandwidth, low power consumption and so on. The principle of the circuit is analyzed in detail. PSPICE simulation results for the proposed circuit in 0.5 mum CMOS technology is included. In the frequency range of 0~20 MHz, the simulation results show the proposed circuit meet ideal port characteristic of CCCII.

The paper presents a new fully differential second generation current conveyor (FDCCII). In this circuit, the voltage relations between the differential input Y and the differential terminal X can be tuned by the extra bias current. The principle of the circuit is analyzed in detail. The simulation results show that the port characteristics of the proposed FDCCII are satisfied in the frequency range of 0~30 MHz.

the paper presents a new differential current - controlled second generation current conveyor circuit with multiple outputs (MO-DCCCII). The principle of the circuit is analyzed in detail. In this circuit, the voltage relations between the differential input Y and the differential terminal X can be tuned by the extra bias current and no restriction is needed about any drain channel sizes of MOS. The simulation results show that with ±1.5V supplies, in the frequency range of 0~30NMHz the port characteristic of MO- DCCCII is satisfied. In the frequency range of 0~5MHz. In the last, as an application, a differential ladder current-controlled current-mode filter based on MO-DCCCII is realized and simulated.

The effect of lead screen on scintillators was investigated experimentally with the Zhengzhou EAS Array. The particle numbers recorded by shielded scintillators were varying with the thickness of the screen, and the best angular resolution of the array did not correspond to the smallest particle number recorded by the shielded detectors.

The paper presents a systematic method of designing nth-order CCII (second generation current conveyor) filter with multiple-loop feedback. Various kinds of structures of lowpass filters can be obtained by this method. At same time, the synthesized filters have high impedance. With RC elements grounded, the filters are integrated conveniently. Design example of 3th-order Butterworth filter and its computer PSPICE simulation results is also given.

In this paper, we design and realize a type of dual-polarization base station antenna on the basis of an L-strip patch antenna for mobile communication. To improve the polarization isolation of the antenna, a novel scheme is proposed which uses the two adjacent units to counteract the coupled components. In order to allow the antenna's vertical pattern to accord with the requirements, a genetic algorithm is used to compute the optimal spacing between units and feed phase of every unit. The array antenna of four units is tested and the results are satisfactory.

The accuracy of speech recognition is still a bottleneck to baffle the application of speech technology. We may improve the accuracy of recognition greatly by using context knowledge efficiently. In Web speech browsing, a user's speech input is usually one element of a finite set. Based on these observations, the paper first defines a kind of similarity between two Chinese text strings, then processes the recognition results of the engine to acquire more accurate results. Experiments show that our approach is mostly efficient.

A KHN (Kerwin-Huelsman-Newcomb) current-mode filter circuit based on MOCCII (second generation current conveyor with multiple outputs) is present. The circuit, which is constructed by three MOCCH and six RC elements, can realize a lowpass filter, a bandpass filter and a highpass filter at same time. By a simple current operation, a bandstop filter and a allpass filter can be obtained. The circuit has a low sensitivity and is integrated conveniently for RC elements are grounded. Compared with voltage-mode KHN filters based CCII (second generation current conveyor), it also has a simper structure and much fewer active elements. The non-ideal characteristic of MOCCII is analyzed, and compensation method is present. In the last, the circuit PSPICE imitation results before compensation and after compensation are given.

This paper presents a novel dual-band magnetic resonance with multi-defect hexagonal structure. Staggered defects double hexagonal metal rings was put on a microwave substrate. So the coupling capacity of the two rings was damaged. Then the dual-band magnetic resonance has been obtained. The traditional structure of dual-band is very complicated. But the new structure is simple and the size is also very easy to control. Finally, we combined the novel structure with metal wires to make dual-band left-handed metamaterials. From the result of the HFSS simulation, this left-handed metamaterials has obtained dual-band at 6.5–7.0 GHz and 8.8–9.3 GHz. The dual-band left-handed structure has a great influence on the microwave filter, antenna, and other microwave devices.

In this paper, a novel four-dimensional chaotic system for generating multi-wing chaotic attractors is proposed, and chaotic and hyper-chaotic attractors are generated in different parameters. Besides, basic dynamical properties of the chaotic system, such as equilibrium point Poincaré mapping, dissipativity, power spectrum, Lyapunov exponent spectrum, bifurcation diagram are studied numerically and theoretically. An analog oscillator circuit is designed for implementing the four-wing hyper-chaotic attractors, and the hardware circuit experimental results are shown to be in good agreement with the numerical simulation results. Finally, the four-wing hyper-chaotic system is used for hybrid image encryption of physical chaos encryption and advanced encryption standard encryption algorithm. Because physical chaos is adopted in this system, there does not exist a definitive relationship between plaintexts and ciphertexts. And the statistical characteristics of ciphertexts should be better than those of any other encryption system.

In this paper, we propose method of generating grid multi-scroll chaotic attractors with the positive-type second generation current conveyors (CCII+). Firstly, a three-dimensional grid multi-scroll chaotic system is presented. Some basic dynamical properties are studied. Furthermore, we construct the saturation functions with current output and design the chaotic system with series structure by using current conveyers. In the whole design the port parasitic parameters of current conveyers are taken into considerations. By analyzing we could learn that the circuit can work in a higher frequency range. Finally, the effectiveness of this method is verified by circuit implementation.

A new, low complexity, ultra-wideband 3.1–10.6 GHz low noise amplifier (LNA), designed in a chartered 0.18 μm RFCMOS technology, is presented. The ultra-wideband LNA consists of only two simple amplifiers with an inter-stage inductor connected. The first stage utilizing a resistive current reuse and dual inductive degeneration technique is used to attain a wideband input matching and low noise figure. A common source amplifier with an inductive peaking technique as the second stage achieves high flat gain and wide −3 dB bandwidth of the overall amplifier simultaneously. The implemented ultra-wideband LNA presents a maximum power gain of 15.6 dB, and a high reverse isolation of −45 dB, and good input/output return losses are better than −10 dB in the frequency range of 3.1−10.6 GHz. An excellent noise figure (NF) of 2.8−4.7 dB was obtained in the required band with a power dissipation of 14.1 mW under a supply voltage of 1.5 V An input-referred third-order intercept point (IIP3) is −7.1 dBm at 6 GHz. The chip area, including testing pads, is only 0.8 × 0.9 mm2.

This paper presents a current controlled fully balanced second-generation current conveyor circuit (CF-BCCII). The proposed circuit has the traits of fully balanced architecture, and its X-Y terminals are current controllable. Based on the CFBCCII, two biquadratic universal filters are also proposed as its applications. The CFBCCII circuits and the two filters were fabricated with chartered 0.35-μm CMOS technology; with ±1.65 V power supply voltage, the total power consumption of the CFBCCII circuit is 3.6 mW. Comparisons between measured and HSpice simulation results are also given.

In this paper we propose a novel grid-scroll chaotic attractor generator based on the second generation current conveyor(CCII), which is used for hybrid image encryption of physical chaos encryption and advanced encryption standard (AES) encryption algorithm, because CCII has a higher speed and larger dynamic range than ordinary operational amplifier and can generate multiscroll physical chaotic signal with higher frequency and more complex dynamics properties. The hybrid encryption system of multiscroll physical chaos encryption and AES encryption based on the CCII, does not assure the relationship between plaintext and ciphertext, and the statistical characteristics of ciphertexts in this algorithm should be better than those of any other encryption system. The difference in statistical property of cipher text between the two cases is studied. One case is that the ciphertexts come from different schemes, i. e. the hybrid and the single stage ones, respectively, and the other is that the ciphertexts are generated by chaotic signals with different numbers of scrolls in the same algorithm. We design and implement the chaos circuit based on CCII, and simulat the encryption system. The results shown that they are in agreement with the theoretical analyses, and that the bigger number of scrolls chaotic system causes the weaker correlation of ciphertexts.

This paper propose a versatile building block called universal current conveyor (UCC), this circuit has the fully balanced structure, it can reduce common mode signals in a great extent. With this circuit, all the previously proposed current conveyors can be realized by proper connecting. Pspice simulations of the UCC and its current conveyor realizations are given in this paper. 1

The paper presents a CMOS differential second generation current-controlled current conveyor circuit with multiple outputs (MO-DCCCII). The principle of the circuit is analyzed in detail. The circuit can restrain even harmonics, common-mode signal. It can apply in digital-to-analog mixed circuit design and signal processing. The simulation results show in the frequency range of 30MHz the proposed MO-DCCCII circuit meet ideal port characteristic of MO-DCCCII. In the last, as an application, differential current-mode filters based on MO-DCCCII are realized and simulated