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Due to a weak adhesion, the delamination occurred frequently in the interface between the epoxy compounds and lead that results in a performance failure normally. Several treatments, such as plasma and chemical modifications, have been developed and applied to enhance the bonding force in the interface of both materials. In this study, an anchor shape of the lead, as a mechanical locking microstructure, was developed and fabricated on the lead to improve the bonding of packaged epoxy molding compound. The fabrication technique was composed of three mainly steps which are the photolithography, chemical wet etching and electroplating process. The parameters of each step were studied and obtained for the fabrication of copper micro-anchor structure. Furthermore, force-displacement curves corresponding to the separation were obtained from the finite element simulations using a linear elastic model. The simulation result showed that the pull-off force was raised by 69 percent.

Aiming at PnP problem for an camera with unknown focal length which the reference points number greater then six, propose an algorithm with high accuracy and speed. The method consist of three steps: 1) four non-coplanar virtual control points are selected and the linear relationship between those virtual control points and space point are solved; 2) Based on above result, linear equations according to the relationship between space points and virtual control points and the image points are setup, and then image coordinates of virtual control points and camera internal parameters are solved by these equations; 3) rotation matrix and translation vector are solved by OI algorithm according to virtual control points and their image points. Experimental results show that our algorithm has a higher accuracy than currently accepted algorithms for PnP problem with uncalibrated camera and even better than state-of-the-art algorithm for calibrated camera. Further more, our algorithm can converge to correct result in a short runtime, and is of better robustness.

According to the infrared imaging mechanism, this paper proposes a Nonuniformity Correction（NUC） enhancement method to improving the image quality of Infrared system. analyzing the connection between the responsivety and the nonuniformity of each pixel on infrared focal plane array (IRFPA), gain and offset coefficients were updated gradually, calculating the image of a scene threshold gray level information, a new histogram was constructed. which makes this ideal can be implemented by FPGA. the experimental results indicated that this method can improve the quality of imaging for infrared system and applied to real-time hardware system.

Non-repudiation of a mobile digital rights management (DRM) ensures that when a user (U) sends some message to a Rights Issuer (RI), neither U nor RI can deny having participated in this transaction. An evidence of a transaction is generated by wireless PKI mechanism such that U and RI cannot repudiate sending and receiving the message respectively. U generates a mobile agent which carries encrypted payment information to RI. This mobile agent is also issued a proxy certificate by U; this certificate guarantees the binding relationship between them. One trusted third party acts as a lightweight notary for evidence generation.

It is possible to prevent collapse of whole post-fault power system, which is in unstable condition, by determining the splitting boundary to calm down system oscillation. A fast splitting boundary-searching method for power system controlled islanding is presented in this paper. The aim of this method is that the generation load imbalance in each island is as small as possible. The method contains three phases: firstly, domain of each generator is formed according to power flow tracing algorithm; secondly, initial splitting boundary is determined based on generators' grouping information; thirdly, the final splitting boundary is got based on initial splitting boundary. A program is developed based on the method. Simulations on IEEE 118-bus power system show the proposed method is effective and fast.

Controllable series capacitors have been utilized to damp swings resulted from large transient disturbances in power systems, and the switching time of the capacitors has distinct influence on the swings of the machines. The reason that different switching time of the series capacitor brings out different stability of the system is analyzed in this paper, a method for calculating the optimal switching time is also proposed. The optimal switching time satisfies the following condition: the transient energy of the system is minimum after the capacitor is switched. Simulation results with a 9-machines power system show the effectiveness of the method.

In this paper, a method is proposed for fast and accurate online detection of transient instability based on real-time measurement. The cluster of critical machines is determined and refreshed at each time. Determination of the irrevocable loss of synchronism is made based on the geometric characteristic of critical machines trajectory. Unlike the previous extended equal-area criterion method, it is unnecessary to calculate the unstable equilibrium point. The speed of algorithm is fast enough to prevent system from transient instability. Simulations are carried out on the IEEE 50 generator test system and a real power system. The results indicate that the proposed method has the features of reliability and effectiveness in identifying the loss of synchronism with inter-area mode.

The neutral point potential of the grounding transformer will be changed when HVDC system operates in a dc monopole ground return mode and dc bias may be generated. Dc bias will change exciting currentdasias waveform. Then large quantity of even and odd harmonics will be produced. The harmonics will do harm to the transformer and its protection. This paper uses PSCAD/EMTDC to create a simulation model. It emulates exciting current of a practical 750 kV single-phase transformer in variant cases under dc bias. It studies the distortion of exciting current, harmonic distribution, the peak value of the exciting current under dc bias. Meanwhile, the performance of transformer protection in this harmonic environment is analyzed. The loss made by exciting currentpsilas distortion and elevated temperature rise of core tie-plate are quantitative calculated.

In this paper, a method, which is essential in initiating emergency control measures, is proposed for fast and accurate online detection of transient instability based on real-time measurement. Under a certain disturbance, the candidate critical cluster of power system is predicted and refreshed at each sampling step. The method identifies the loss of synchronism at each time step by observing the geometric characteristic of the post-fault trajectory of the generalized one-machine equivalent system. A new structure of the emergency control scheme relies on SIME (for Single Machine Equivalent). It is unnecessary to calculate the unstable equilibrium point and some limitations caused by the time-invariant assumption are also eliminated. Simulations are carried out on the IEEE 50 generator test system and a real power system. The results indicate that the proposed method has the features of reliability and effectiveness in preventing the system from the loss of synchronism.

Spread spectrum technology can effectively solve the problems such as bad channel environment, multi-path fading etc between mobile station and subscribers. With the rapidly development of micro-electronic and EDA technology, now the research on base band signal treatment is more concentrated on how to implement high system performance and low bit error rate. This paper introduces a new error correction scheme which combines BCH encoding with interleaving technology, gives out a simple and efficient method to implement the error correcting code and interleaving technique of source coding, and spreading sequence generation which is suitable for the mobile communication, and designs circuit under electronic design software Quartus II using VHDL. At last the accuracy of this method was verified on FPGA.

A new detection scheme for transient power systems instability with geometrical characteristics of trajectory in partial angle center is presented, and the generalized energy function is chosen to verify the validity. Avoiding seeking the center of whole system angle, this scheme gets rid of the limitation in the practical application. The method of instability detection using partial wide-area measurement information is discussed. The simulation results in IEEE_145 bus systems demonstrate that when the out-step generator possesses observation condition, system instability is still able to be detected via the proposed criterion, and the extent of the absence of the whole system trajectory information only leads to the difference of the instability detection time. The proposed scheme enables to detect system instability ahead of the traditional time domain simulation methods as 0.3-1s.

With the wide application of synchronized phase measurement unit (PMU) in power system, the wide-area measurement system (WAMS) has enabled the use of a combination of measured signals from remote location for global control purpose. Since in nature power system stability is related to all generators, the introduction of wide-area information into nonlinear integrated control can improve the dynamic performance of power system and enhance power system stability. According to multivariable inverse system theory, this paper verifies the invertibility of excitation and turbine control system for a turbogenerator under the center of inertia reference frame (COI), and presents a novel nonlinear global integrated controller based on wide-area information including the on-line measured center of rotor angle and total unbalanced power. This controller makes the relative rotor angle to the center of angle return to its pre-disturbance value by modulating excitation voltage and turbine valve, and is considered as a "control the local to serve the global" controller. Digital simulation demonstrates that the four-machine power system under the nonlinear global integrated control has less settling time, swing times, oscillatory peak value and more critical clear time and better transient stability performance than that under PID control and nonlinear decentralized integrated control.

It is reported in the following article the succesful use of millimeter wave systems in the model simulation measurement to determine the scattering characteristics of aircraft targets and any details in the target which may still affect the scattering characteristics of the target.

It's important to realize information access of distribution automation and home intelligent networks using distribution high speed-carrier communication. The couple device is one of the most import devices to ensure the quality of the information transmission. In this paper we firstly analyze the request to the couple's structure and frequency band from the views of the networks' structure and information transmission rate of the distribution communication. Then we research the distribution impedance character in high frequency, further more we advise the design principle of the couple device. Finally we present the design method of the couple device by two examples and validate the couple's character by the simulation and experiment analyze.

The performance of manganin resistance gauges under high static pressure is evaluated. The accuracy of several interpolation- (or extrapolation-) based mathematical-models is compared. It is shown that if the gauges used at pressures below 1 GPa are calibrated at a given constant temperature and used at that temperature, the complete mathematical-model is unnecessary. However, a complete model for the variation of resistance with both pressure and temperature is required in the pressure range from 1 GPa up to 20 GPa, because the temperature changes due to compression or expansion of the pressure-transmitting medium can be quite pronounced. >

The high-static-pressure metrological characteristics of 1-GPa manganin resistance gauges are investigated. Nonlinearity is measured by means of a secondary standard-free piston gauge. A second-order mathematical-model is established, with an interpolation accuracy reaching 0.07%, as verified by calibration tests. The results obtained indicate that manganin resistance gauges exhibit very good stability, repeatability, and reproducibility. >

A new high temperature transducer is described. The transducer employs NiCr-NiSi thermocouple as a sensing-element and can directly measure flash surface temperature at 1230/spl deg/C under high pressure up to 400 MPa. It can be reused by abrading the hot-junction after it ablated. The response time constant is less than 1 /spl mu/s which was verified by theoretical calculation and by a calibrated test. This paper relates to the features of the transducer and the technology keys to the design of high-pressure-withstand poles, micrometer-order clearance between poles and high-resistance insulation. The theoretical analysis and calibration test are presented. The measurement results and curves of the inner-barrel surface temperature for a certain gun are given. >

A new type of high temperature withstanding high pressure transducer is described. The transducer uses Manganin wire as sensing-element and can measure pressure up to 250 MPa under condition of high temperature up to 200/spl deg/C for a long time. The expanded uncertainty in measurement of the transducer is less than 1.0% verified by calibration and practical use. This paper discusses the key technology issues, such as high pressure sealing and linearity correction under the temperature range from 0/spl deg/C to 200/spl deg/C, etc. The calibration test under high temperature condition is carried out against a free piston gauge having an uncertainty of 0.1%. Measured results in practical use on high-pressure cauldrons for growing man-made crystals are given.