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Nondestructive Testing (NDT) for moving ferrite metal component is a challenging topic because of the magnetic fields generated by the motion induced eddy current (MIEC) and ferrite magnetization in sample. The magnetic fields distribution inside the moving ferrite metal are more complicated. Therefore, an accurate and efficient NDT technique for monitoring the health condition of metal component with the high-speed is an urgent problem. In order to investigate the influence of velocity effect on defect detection of ferrite metal components, a numerical simulation model of the electromagnetic NDT system by using Finite element method was established, and the relationship between the detection signal and velocity considering the different defect depths and widths are deeply analyzed. The results show that with the increase of the speed, the MIEC is stronger and the dragging effect is more obvious, which are the new phenomenon for the moving sample compared with the static sample. Furthermore, the defect width and depth can be reflected by the magnetic flux density, and the strength of the magnetic flux density increases with the increase of the speed, which is advantageous to the localization and characterization of the defect. The findings in this paper are helpful and beneficial to propose a new NDT method for the defect detection in the moving ferrite metals, such as rail tracks and pipelines.

For gold exploration and sustainable exploitation, it has great significance for the genesis of gold deposit mineralization enrichment regularity. Jiaodong area is one of the most important gold producing areas in China, whose reserves account for about 1 /3 of proven rock gold reserves in China. In this paper, we take northwest of Jiaodong gold concentration area, the eastern side of Yishu fault zone and Xincheng fault structure zone as the main research object to obtain the zircon U-Pb age of the Linglong granite and guojialing granodiorite, which is 158.53 + 0.79Ma and 135.56 + 0.53Ma. On the basis of the general analyzing research of the spatial variation law of ore controlling structure, the dynamic characteristics of ore controlling faults, the spatial location mechanism of industrial ore-bodies and other mineralization enrichment regularity, the analysis shows that there is another mineralization enrichment section in the deep part of the mining area. Namely, the dip angle of the fracture where occurrence tend to be gently is a favorable region for mineralization, that is the second mineralization enrichment segment, whcih provides theoretical basis for the next step of prospecting work.

Production scheduling system of open pit mine is the key process of mining production, and the optimization effect of the production scheduling system of mineral resources has direct impact on the production efficiency and production efficiency of open pit mining. Based on the actual problems in mining producing, this article adopts multi-objective optimization to propose a optimized model for tramcar transport dispatching organization. Then a FLSPT rapid algorithm is used to put forward a shortest path algorithm for resource scheduling, which can obtain the shortest path between two points. Then an optimal planning algorithm of open pit truck and shovels are proposed to provide real-time scheduling and maximize the mine production resources. The case analysis shows that our method has the advantages of high precision and high efficiency, and it is easy to be implemented, which also shows practical value.

This article divides rural public goods into two categories, productive goods and unproductive goods. It probes into mechanism of action of rural public goods supply influence on rural residents consumption. It reports the change of our country's rural residents consumption level and consumption structure, and the current situation of rural public goods supply and the problems that adverse to expanding rural residents' consumption demand. And then it explains the relativity and Long-term relationship between the rural public products supply and the rural residents consumption using linear correlation and impulse response function. The results of the study show that both the rural public goods supply level and supply structure have a stable long-term equilibrium relationship with rural residents consumption level and rural residents income level, also causing a significant positive role in promoting the rural residents consumption level; The development direction of the future should be to improve the rural public goods supply which is beneficial to the forming of the rural residents consumption.

For the detecting plaque buildup and calcification in the coronary artery, the cardiac computed tomography (CT) angiography is widely used in clinic. However, the soft and calcified plaque is hard to distinguish from contrast enhanced blood vessel with conventional CT. The photon counting detector has an advantage over the conventional detector by detecting energy information of each photon. The application of optimal energy weighting factor for each energy window based on energy information of each photon can be improve the identification of plaque. The purpose of this study is to investigate, with simulation, the ability to distinguish plaque from contrast enhanced vessel using optimal energy weighting factor. The photon counting imaging system consists of a micro focus x-ray source and CdTe sensor was simulated using the Geant4 Application for Tomographic Emission (GATE) V6. The source to phantom rotation distance and phantom rotation to detector distance were set as 600 and 400 mm, respectively. The energy spectra were calculated at 80 kVp with 1 mm aluminum filter using Spekcalc program and used as source. A phantom consisted of iodine and hydroxyapatite (HA) which simulates contrasts enhanced blood vessel and plaque, respectively. The projection based energy weighting factors at each energy window were calculated and applied. The identification of HA with respect to iodine was evaluated using signal-difference-to noise ratio (SDNR). The SDNR improvements, as compared to image from charge integrating detector were 1.07 and 1.42 for photon counting and energy weighted image at 50 mg/ml of HA, respectively. The SDNR were improved from 1.43 to 21.88 with optimal energy weighting for each concentration. The results showed that the plaque could be distinguished from contrast enhanced blood vessel with optimal energy weighting. However, the result can be depends on the concentration of background contrast media, therefore additional simulation required.

With the development of information technique, the power of image processing software become stronger, and we can edit the digital images more easily. So the copyright protection, the integrity authentication of digital image becomes an urgent issue. At the same time, the rapid development of medical technique, there are more and more digital images, and they need be preserved, transmitted, an so on. However, the copyright of it should be researched. And the contents of digital medical images contain more important information, and any change of it may result in physiotherapy accident. How to authenticate the digital images' reality and integrity become so important that we should use new technique to protect them. Digital watermarking is a technique that embeds important data into host multimedia, and it can be used in digital right management, authentication and data hiding. In this paper, we will analyze the character of medical images and watermarking technique. And give the basic procedure of them, and analyze the performance of these algorithms.

The design ways and steps of a Low Noise Amplifier used in RF communication receiver for personnel orientation system in mine is been introduced in this paper. The key points are analysis device's stability with Stability coefficient of determination of the ADS software and the input and output impedance matching with Smith Chart and Tuning. Finally, the performance parameters of LNA were obtained with the simulation of S parameters. The final simulation results show that the Use of ADS for low noise amplifier design is useful and has a good reference value for practical amplifier design.

We studied the effect of spectral distortions on X-ray imaging observed by photon-counting detectors. The photon counting-based imaging system used in this study consisted of a micro focus X-ray source and cadmium telluride (CdTe) detector.

Photon counting detector with energy discrimination has made it possible to decompose materials. In this study, we compared two material decomposition methods in CEDM using a Monte Carlo simulation. The K-edge and dual energy imaging methods were used for material decomposition. We designed the cadmium telluride (CdTe) detector based on photon counting using GEANT4 Application for Tomographic Emission (GATE) version 6.0 simulation tools. The CdTe detector was 44.8×44.8 mm2 and thickness of 1 mm. To verify the material decomposition ability, we designed the phantom with GATE. The phantom was a cylinder of breast equivalent tissue material (ICRU-44) containing iodine inserts at various thicknesses ranging from 0.3 to 1.5 mm. Thicknesses of breast equivalent tissue material was 20, 30, 40, and 50 mm. First, to verify the material decomposition ability of K-edge imaging, we obtained image from 34–44 keV energy window because the K-edge energy of iodine is 33.2 keV. Second, for the dual energy imaging methods, we acquired two images with below and above the iodine K-edge energy using one exposure with energy selective windows. Data for material decomposition algorithm were obtained for various combinations step wedge phantom of breast tissue equivalent materials and iodine. The images from the phantom were used to produce the inverse mapping functions. The ability of material decomposition was investigated in terms of a contrast-to-noise ratio (CNR). According to the results, the CNR with K-edge imaging method was higher than dual energy method. The calculated values of CNR with K-edge imaging method were approximately 1.60 times higher than with dual energy imaging method. Our studies may be used as a basis for future studies on X-ray imaging based on photon counting.

The conventional detectors operated in the integrating mode are insensitive to the energy spectral information since the detector output is proportional to the energy fluence integrated over the whole spectrum. Recently, photon counting detectors have been considered to be an alternative device. These detectors are able to measure the x-ray photon energy deposited by each event and reduce the noise which is caused by detector leakage current using energy thresholds. Photon counting detectors with multiple energy thresholds have a significant advantage that material decomposition is possible using energy selective windows. In this study, we investigated the capability for material decomposition in images acquired from different energy window widths using the photon counting detector based on cadmium telluride (CdTe).

Engineering education occupies an important position in China higher education and national economic construction. Practice teaching is a very important part of engineering education. It has an unsubstitutable function in cultivating students' creating sense, spirit and ability. But now some problems exist in the practice teaching in engineering education. In order to reform and innovate the practical teaching, a delicate practical teaching system must be set up and the practicality of the course must be strengthen. This paper studies and discusses the construction problem of practical teaching, explores the new route and new method in practical teaching.

With the gradual increase of ship tonnage, the voyage operating efficiency becomes the core of competition. In actual operation, on the one hand, in order to improve ship carrying capacity, the phenomena of overloading and neglecting ship safety existed. On the other hand, due to the improper and wrong judgment of maritime supervising authorities, many ships didn't reach their maximum carrying capacity. And sometimes ships were detained or delayed due to misjudgment of overloading, hence caused unnecessary financial and reputation losses. The discrepancy of load line determination is the main reason. This paper analyzes the determining principle of load line and load line immersion based on interpretation of “International convention on load lines, 1966” properly. By using the methods of reasoning and checking, it discusses the judgment errors caused by the impact of hogging and sagging, inclination, and water density overboard, and proposes the correct methods of determining overload. It has a practical guidance for improving ship operating benefit, preventing overloading and ensuring operation safety.

The L-band band-pass interdigital filter was studied, a large number of experimental data showed that bandwidth narrowed with the increasing of resonator width, and the center frequency becomes larger with the reducing of the resonator length; the bandwidth will widen when the distance between resonator was reduced. Change coupled structure, increase the effective coupling area of the microstrip line can make the structure of filter more compact, so as to reduce filter area. Based on these conclusions, a new type of filter was designed. Compared with the traditional interdigital filter, the size of the new filter was only 71.4% of that of the original one.

A new method for the workpiece image detection was proposed according to the characteristics of online work. The algorithm extracted orientation codes as a feature and consisted of two stages: rough matching and precision matching. Firstly, some points with the matching rate in a certain range were selected using histograms of orientation codes and rotation angles were computed roughly. In the second stage, the template was rotated in terms of the angle computed, matching based the orientation code between template and subimage was performed only for the points selected. Experiments result demonstrates the proposed method can work well even when workpiece was rotated or light fluctuates.

Several routing schemes for Low Earth Orbit (LEO) satellite IP networks have been proposed in recent years, but little work has been done to consider the satellite network topology and traffic load change simultaneously. A distributed routing algorithm combined with Multi-Agent System (MASSR) is proposed in the paper. As MASSR relies on both passive and active information gathering and exchanging, it not only provides a traffic-adaptive and multi-path routing, but fast tracks the change of network topology as well. Simulation results show that, compared with AntNet, MASSR presents improved end-to-end delay as well as enhanced robustness.

E-commerce Web sites provide the economic information by query interfaces. Query interfaces are considered as Deep Web services that indirectly reflect the real schema of the hidden databases. The valid accessing method of Deep Web is through query interfaces. However, the query interfaces are designed and coded in different development models and using different programming languages and the semantic relation is very complicated. To improve the accuracy of extracting attributes, an approach is presented to extract the attributes heuristically. During the extraction, attributes are enriched utilizing Ontology by which we get deep semantic understanding of query interfaces. Experiments over real-word domains show the utility and ability of the algorithm for grasping the information of query interfaces.

Various Au bonding wires which have different diameters from 25 um to 12 um, and purity of 2N and 4N are used for studying possible problems in ultra fine wire bonding. As wire diameter gets finer, grain size gets finer and portion of direction in wire texture is increased due to high working ratio. Moreover, as wire diameter gets finer, eccentricity of FAB (Free Air Ball) get worse and, for soft 4N wire, neck broken issue is occurred in 12 um bonding due to low neck strength, and for hard 2N wire, bond-off issue is occurred due to bad initial bondability. Also initial IMC (Intermetallics) coverage gets worse and HTST reliability is dramatically dropped in ultra fine wire application. Therefore, soft 2N wire which has relatively low FAB hardness and Pd-based dopant composition could be an alternative to solve these issues in ultra fine wire.

OFDM system can improve frequency band utility, decrease symbols interference caused by multi-path effect. It also can obtain reliable data transmission with high speed. The paper studies the channel estimation technique in a digital radio broadcast receiver based on OFDM-DRM. Due to the time and frequency selective variance of the channel encountered during OFDM transmission, the channel response has to be estimated in order to get exact data. This is done by using the known scattered pilots transmitted in OFDM symbols. OFDM based digital radio system adopts linear interpolation, windowed FFT interpolation and Wiener interpolation, in which Wiener interpolation is the best but requires a large quantity of computational consumption. The paper analyzes the Wiener algorithm..and simulates the MSE versus SNR for different Wiener filtering methods, and presents the flow charts of Wiener algorithm and realizes them in the computer.

A fair and adaptive call admission control algorithm for multimedia low Earth orbit (LEO) satellite networks was proposed. Based on current call dropping probability of destination cell, this algorithm reserves bandwidth for handoff calls using double threshold method. To avoid the discrimination of quality of service (QoS) caused by the allocation based on fair bandwidth, this algorithm adopts the bandwidth allocation rule based on fair QoS. Simulation results show that the proposed algorithm can accurately and adaptively reserve bandwidth, present satisfactory call blocking probability and greatly reduce handoff call dropping probability, while guarantees the high bandwidth utilization.

A novel adaptive call admission control algorithm for multimedia low orbit satellite networks was proposed. Based on real-time call dropping probability of destination cell, the algorithm is able to reserve bandwidth for handoff calls combining probability threshold method and fair utility allocation scheme. Simulation results show that the proposed algorithm presents satisfactory new call blocking probability and greatly reduces handoff call dropping probability, while guarantees the high bandwidth utilization.

Recent research indicates that self-similarity is a common phenomenon in wired network. However, there are no sufficient studies that focus on the characteristics in wireless network, especially in low earth orbit (LEO) satellite network. This paper presents a practicable model based on analysis of aggregate self-similar traffic and impact on performances of LEO satellite network, and then validate that the traffic in LEO satellite network is self-similar. Then, the quality of service (QoS) measures under self-similar traffic such as queue length and buffer size are discussed.

As the structure of generator is complex, and the saturated magnetic field is nonlinear, it is difficult to use generator's mathematic model to calculate field current directly, and then hard to use the deduced method to identify rotor interturn short-circuit fault, the computation time is long, and the computation precision is not good, so it is difficult to diagnose online. We proposed a new Radial Basis Function Network (RBFN) in this paper, it is two levels iteration clustering algorithm. This method overcomes the shortcomings that other algorithm have, it can compute the nerve unit number, center and width of RBSN implication layer automatically, and the clustering result is more reasonable, consequently increase the precision of RBSN. In condition of not adding any equipment, using actual measured inactive power, active power and terminal voltage etc. electric parameters of QFSN-300-2 generator as input, and in virtue of self-adaptive RBSN to identify generator field current, combining rotor inter-turn short-circuit fault diagnosis model to identify rotor inter-turn short-circuit fault online, it is faster than simply use generator mathematic model, and has high precision. After certification, the result is: comparing to the traditional diagnosis model, it increases the diagnosis precision and speed greatly, and satisfies the need of online identification.

This paper presents an omni-directional image generation algorithm on spherical coordinates by compensating vignetting and illumination effects. The algorithm generates an omni-directional image by transforming each planar image to the spherical image. In this paper, vignetting and illumination compensation methods are proposed for realistic and seamless omni-directional video systems. We can synthesize any point of view from the stitched omni-directional image on the spherical coordinates. Experimental results show that the proposed algorithm can effectively generate the omni-directional image and with real video sequences. Furthermore, the proposed omni-directional system with vignetting and illumination compensation is shown to be approximately 1~4 dB better than that which does not consider the said effects.

In this paper, a new technique for detecting inter turn short circuit fault in large turbogenerator rotor winding is presented. Based on single-end fault information, this new technique applies wavelet analysis method to inspect abruptly changed signals. The transient current traveling wave that generated in the rotor winding inter turn short circuit contains ample fault information, and its basic characteristic is current "abruptly changed". According to the "abruptly changed", there are modulus maxima after wavelet transform, and we can detect generator inter turn short circuit fault through this characteristic. We have conducted correlative experiment on dynamic analog experiment unit, and the coincidence conclusion with the theory analyses is obtained.

A 2 /spl mu/m design ruled, High-Densified, and Low-Power-Consuming Bipolar Integrated Circuit process has been developed. The breakdown voltage of the transistor is 15 V and it has a stable current driving capability at high current (about 1 A) due to the low saturation voltage between emitter and collector. NPN Tr. has been fabricated to prevent leakage current and has good Cut-Off frequency (fT=5 GHz) by using a polysilicon emitter. The characteristics of this process is a Double Epi Process to form a high concentrated N+BL in VPNP Tr. (that is the same as in NPN Tr.) which can protect the parasitic Tr. operation like Latch-Up Phenomenon (Ihold=26 mA, Pa-PNP Tr, hFE=4). And it also includes the IIL Device without an additional mask layer. This process is a low voltage, high current power complementary bipolar process that merges a variety of NPN, VPNP, LPNP, SPNP, IIL devices, and a diffusion resistor.