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The query image is usually a simple and single object in image retrieval, and the reference images in the database usually have many distractions. The precision of image retrieval can be greatly improved If the target regions in the database image are extracted during retrieval. So this paper proposes a Bow image retrieval method based on SSD target detection. First, the training gallery is manually annotated to record the location and size information. Second, the SSD target detection model is trained with the labeled training gallery to obtain the target object SSD model. Third, the SSD model is used to locate the similar target regions of the reference image and the query graph. Finally, the target region information is mapped into the convolutional features, and these feature vectors are used for image similarity matching. The performance of the proposed method is evaluated on Paris6k, Oxford5k, Paris106k and Oxford105k databases. The experimental results show that the accuracy of image retrieval will be greatly improved by adding optimization methods in the proposed image retrieval framework. The image retrieval accuracy of this method is higher than that of similar methods in recent years.

As the support networks of the electric power grid, power communication networks (PCNs) become more complex and vulnerable due to the increasing scale of the electric power grid. Identifying and protecting the critical nodes in PCNs in advance is an effective way to reduce network vulnerability. Owing to the large differences in vulnerability indicators of different layers in the PCN, it is difficult to find the critical nodes, which have great impacts on all vulnerability indicators. Therefore, the goal of this study is to identify the critical nodes that have greater impacts on different layers, rather than nodes that have the greatest impact on a single layer. Therefore, the authors present a model to analyse the node in the PCNs from the physical topology, traffic distribution, and service importance distribution to calculate the node importance in the physical topology layer, the transport layer, and the service layer, respectively. Combined with a multi-layer critical nodes identification algorithm (MCNIA) proposed, the node critical degree is obtained so that it can identify the critical nodes in the PCNs. The vulnerability analyses of PCNs under critical nodes attacking prove that MCNIA can identify critical nodes in the PCNs precisely.

Background: Rolling mill vibration mechanism is very complex, and people haven't found a satisfactory vibration control method. Rolling interface is one of the vibration sources of the rolling mill system, and its friction and lubrication state has a great impact on the vibration of the rolling mill system. It is necessary to establish an accurate friction model for unsteady lubrication process of roll gap and a nonlinear vibration dynamic model for rolling process. In addition, it is necessary to obtain more direct and real rolling mill vibration characteristics from the measured vibration signals, and then study the vibration suppression method and design the vibration suppression device. Methods: This paper summarizes the friction lubrication characteristics of rolling interface and its influence on rolling mill vibration, as well as the dynamic friction model of rolling interface, the tribological model of unsteady lubrication process of roll gap, the non-linear vibration dynamic model of rolling process, the random and non-stationary dynamic behavior of rolling mill vibration, etc. At the same time, the research status of rolling mill vibration testing technology and vibration suppression methods were summarized. Time-frequency analysis of non-stationary vibration signals was reviewed, such as wavelet transform, Wigner-Ville distribution, empirical mode decomposition, blind source signal extraction, rolling vibration suppression equipment development. Results: The lubrication interface of the roller gap under vibration state presents unsteady dynamic characteristics. The signals generated by the vibration must be analyzed in time and frequency simultaneously. In the aspect of vibration suppression of rolling mill, the calculation of inherent characteristics should be carried out in the design of rolling mill to avoid dynamic defects such as resonance. When designing or upgrading the mill structure, it is necessary to optimize the structure of the work roll bending and roll shifting system, such as designing and developing the automatic adjustment mechanism of the gap between the roller bearing seat and the mill stand, adding floating support device to the drum shaped toothed joint shaft, etc. In terms of rolling technology, rolling vibration can be restrained by improving roll lubrication, reasonably distributing rolling force of each rolling mill, reducing rolling force of vibration prone rolling mill, increasing entrance temperature, reducing rolling inlet tension, reducing strip outlet temperature and reasonably arranging roll diameter. The coupling vibration can also be suppressed by optimizing the hydraulic servo system and the frequency conversion control of the motor. Conclusion: Under the vibration state, the lubrication interface of roll gap presents unsteady dynamic characteristics. The signal generated by vibration must be analyzed by time-frequency distribution. In the aspect of vibration suppression of rolling mill, the calculation of inherent characteristics should be carried out in the design of rolling mill to avoid dynamic defects such as resonance. It is necessary to optimize the structure of work roll bending and roll shifting system when designing or reforming the mill structure. In rolling process, rolling vibration can be restrained by improving roll lubrication, reasonably distributing rolling force of each rolling mill, increasing billet temperature, reasonably arranging roll diameter and reducing rolling inlet tension. Through the optimization of the hydraulic servo system and the frequency conversion control of the motor, the coupling vibration can be suppressed. The paper has important reference significance for vibration suppression of continuous rolling mill and efficient production of high quality strip products.

A multi-wavelength Brillouin erbium-doped fiber laser sensor is proposed and investigated experimentally. It is a linear laser cavity multi-wavelength fiber laser, formed by fixing two high-reflectivity Sangac loop mirrors at both ends. We investigate the laser system output characteristics and test the sensor performance for different temperature. Temperature/humidity and reliable linear-cavity fiber laser sensing operation were successfully achieved. Experimental results show that the temperature sensitivity is $$27.15$$ MHz/ °C and the measurement error caused by frequency drift is about $$\pm 0. 2 8 5$$ °C.

A 3D scanning system involving multiple RGB-D cameras has the potential to accelerate the reconstruction of an object and improve the measurement accuracy because it can capture an object in a comprehensive way. However, the extrinsic calibration of a multi-RGB-D-camera system is a fundamental and challenging problem, especially in a limited field of view. In this work, a system with four SR300 cameras on a platform with a size of approximately 0.64 m2 and an extrinsic calibration method assisted by a tower calibration pattern with circular markers in a limited field of view are proposed. The Hough transform algorithm is used to identify the centres of the circular markers in a colour image, and then the 3D coordinates are extracted by employing the alignment relationship between the colour image and the depth image. An improved adaptive cuckoo search (IACS) algorithm and unit quaternion are proposed to optimize the extrinsic parameters. The effectiveness of the IACS is verified by a comparison with the singular value decomposition (SVD), standard cuckoo search (CS) and two CS variant algorithms. In addition, the accuracy of the proposed extrinsic calibration method is verified by reconstructing and measuring a human foot and a cube box. The mean errors from the standard values of the length and width of the reconstructed foot mode are 0.18 cm and 0.13 cm, and the diameter of the yellow sphere are 0.17 cm, respectively. All of the experimental results show that the proposed extrinsic calibration method has a high calibration accuracy and good potential application prospects.

It is difficult to effectively manage storage of surveillance video, owing to the large volume of data, low value density and limited storage time. This research analyses the concept named as magnitude of value of surveillance video, as well as introduces a valuation system that quantifies the value of surveillance video, providing theoretical foundation for dynamic storage management towards data distribution and optimisation based on magnitude of value. According to the result of experiment, this valuation system has satisfactory performance in differentiating surveillance videos with different value.

Data opening has been the trend in the era of big data, confronting with problems of general engineering implementation of data opening. The data-open-pool (i.e., DOP) framework and the "Catalog-Dataset-Distribution" (i.e., CDD) data description model are proposed in this article based on metadata management and big data storage. It realizes business logics of data involving in data collection, distribution and opening. In addition, it discusses on description and management of data resources on the three layers. Finally, it illustrates examples of convenient implementation of data opening with hierarchical description models of DOP and CDD, and discusses on several problems about the framework.

The core of airplane lifecycle data management is BOM management in the product lifecycle. Aiming at the problem of nonunique data source existing in airplane lifecycle, the paper proposes the airplane BOM management hierarchical system framework based on Single Source of Product Data ( SSPD) and the corresponding technology. The logical unified SSPD is constructed to guarantee the uniqueness of lifecycle data. According to the diversity and complexity of airplane，customer options management and BOM management based on SSPD, are discussed emphatically in the context.

This paper describes the monitoring design on the MES system about the carplant. The network structure and hardware are discussed in general. The system combines information management with supervisory control and works well.

Most motion control systems are designed to satisfy the performance requirement in transient and frequency domain. The actuator effort of the control system is rarely considered during the design process. This paper investigates the effects of input shaping on actuator effort of PD combined with input shaping control for an inertial plant subject to four standard types of inputs. The actuator efforts of the control systems are described in general fomula. The acting regulation of PD controller parameters on the oscillatory frequency and damping ratio of actuator effort is investigated and the effect of input shapping on the magnitude of actuator effort is thoroughly analyzed. The research results show that PD feedback control enhanced with input shaping can effectively reduce actuator effort compared with PD control.

This article takes the Xiamen Sea reef engineering as an example to research the structure response of underwater blasting vibration on 4-story masonry-concrete building. The blasting seismic wave has been field monitored and the data has been analyzed with some means such as wavelet analysis. As a result, the characteristic laws of different floors’ structure responses under the effect of blasting vibration load have been acquired. With the floor increasing, the particles vibration velocity amplification coefficient of the forth top roof relative to the ground is approximately 1.36 to 2.086. The duration period and the main vibrationa are reduced respectively by 14%-28% and by 38%-56%; each floor’s vibration energy mostly concentrates in 0-25Hz’s band. The first floor’s energy mainly concentrates on 0-60ms, mainly distributing in 1st and 2nd frequency band, with the maximum appearing in the 1st band. And the vibration signal energy peak amplification coefficient relative to the ground is approximately 1.783 to 3.866.

An improved routing method to reduce the risk of electric power communication networks (EPCN), called low risk routing method (LRRM), is proposed based on the fact that different types of traffic with different service importance levels in EPCN. In order to calculate the vulnerability of EPCN under artificial attacks, deliberate attack and betweenness first attack models are created. Based on the attack models, a routing model considering service importance distribution, edge betweenness distribution and path length is presented. Taking into account both network risk and service delay requirements, optimized routing is calculated using Dijkstra algorithm and chaotic clonal genetic algorithm (CCGA). Under different artificial attacks, the vulnerability of an EPCN applying LRRM and Shortest Path First method (SPFM) are compared by numerical simulation. The results show that LRRM can effectively reduce the network risk.

The research on a Small Unmaned Air Vehicle(SUAV) has developed with various kinds of advanced technology, such as micro-machine technology, micro-motor technology, micro-electronics technology, integrated technology, and especially the nanotechnology. As the core of SUAV systems, the reconfigurable technique of flight control system can applie to the unknown fault and damage, and enhance the survivability and mission effectiveness of the aircraft obviously. It has become one of the attractive research subjects in modern aircraft integration design area. In this paper, several important methods for reconfigurable flight control are introduced or analysed, and some focus problems on the reconfigurable flight control technique are summarized and proposed. Finally, an outlook is did about the development tendency of reconfigurable flight control technique.

In this paper, the driving manner and design method are discussed for the elbow joint of one kind of robot artificial limb. On the basis to satisfy ergonomics, some technical parameters required for the riving manner is make out for the elbow joint. In order to ensure implement for diverse requests, optimization design is adopted in this case. Based on the peculiarity of structure and movement, variables, constraint functions and objective function are all projected reasonably. Complex method is handled to optimize the parameters. Finally, with graphics simulation, it is proved that optimization results suffice the practice requirement commendably

A recent effort to control urban freeway network and alleviate congestion is using graphical route information panels (GRIPs). This paper first introduces function and location of GRIPs for the urban freeway network in Shanghai, China. Second, it deals with the information display method of GRIP; Then, it proposes a macroscopic traffic flow model based simulation platform for investigating control benefits of GRIP. The simulation platform combines Papageorgiou's METANET model with the GRIP influence model. Next, control benefits of GRIP in terms of re-current congestion alleviation were examined on a hypothetical freeway network through a case study. Simulation results indicate that GRIP have a positive potential of reducing re-current congestions and facilitate more efficient use of road infrastructures. Last, Concluding remarks are given.

Analysis has been made of testicular biopsies from 13 volunteers, 7 of whom received over 100 periods of 20–30 W of 915 or 2450 MHz microwave radiation. The other 6 subjects received fewer than 100 treatments. The radiation was localized to the scrotum for contraception, and the surface temperature was raised to 40–42° C. The results of the biopsies shows that human testes possess a greater tolerance to microwave than those of other species, such as rabbits or rats. Examined 0.5 years after cessation of treatment, it is evident that spermatogenesis resumes, even though they have been irradiated more than 100 times. No individuals were found to be sterile, though spermatogenesis had been severely inhibited during the period of exposure. Vestiges of damage remained, however. The number of degenerate sperm-atogenic cells was increased. and there was a thickening of the limiting membrane of the seminiferous tubules. Some hyaline degeneration was also present. There were local increases or decreases in the num...

Following the principles of agent-oriented analysis and design, the urban traffic micro simulation system was divided into several modules and a micro simulation framework based on multi-agent was obtained on the basis of requirement analysis. The paper discuss agent-oriented traffic micro simulation modeling process, beginning with traffic flow generation model, car-following model, it gives design scheme of agents in the system. Besides, the paper gives simulation systempsilas infrastructure and simulation flow. Thus a reusable and flexible framework of urban traffic micro simulation system was achieved.

The paper introduces the concept of game theory into analyzing driver's response to guide information, as well as the interaction between driver's decisions. Results show that guide system is not only necessary but also important.

Information classifying and indexing are the most important services the information navigating system usually provides. One kind of automatic information classifying subsystem used in the internal information navigation system and its implementation is mentioned. The structure and implementation of its classifying subject dictionary is also touched. In the end, the indexing method to the data which is manipulated by the automatic information classifying system is also provided.

A new four-dimensional chaotic system is reported in this paper. Basic dynamic properties of the new system are investigated via theoretical analysis，numerical simulation，Lyapunov exponent，Lyapunov dimension and Poincare diagrams. Finally the chaotic circuit is designed and realized by the Multisim software. It confirms that the chaotic system is different from the exisiting chaotic systems and is a new hyperchaotic system.

A new three-dimensional chaotic system is reported in this paper, which is different from the Lorenz and Chen systems. This new system contains five system parameters and two quadratic cross-product terms. The basic dynamic properties of the new system are investigated via theoretical analysis, numerical simulation, Lyapunov exponent spectrum, bifurcation diagrams, Lyapunov dimension and Poincare diagrams. The different dynamic behaviors of the new system are analyzed when each system parameter is changed. Finally, the chaotic circuit is designed and realized by the Multisim software. It confirms that the chaotic system can be achieved.

Tantalum and niobium silicides formed by Scanning Electron BeamZhang Guobing and Wang yangyuanDepartment of Computer Science and technology, Peking University Beijing. ChinaLin shi- Chang, Zhang yan sheng, Fan bing linInstitute of Electronics, Academia Sinica, Beijing, ChinaAbstractThe properties and structures of tantalum and niobium silicides formed by rapidannealing of scanning Electron Beam have been investigated. The fine layers of tantalum andsilicon Niobium and silicon were deposited by co- sputtering system and co- evaporatingsystem, respectively. The Scanning Electron beam Equipment with quasi -linear source wasused to realize the rapid annealing for forming the TaSi2 and NbSi2. The x -ray diffractionRBS and TEM have been used to characterize the Composition and structure of silicide film.The best conditions of forming silicides has been presented. The single phase TaSi2 andNbSi2 and the resistivity of 50 Micro Ohm -Cm have been obtained in annealing time of 10 -100seconds. The results have been compared with those of furnace thermal annealing.IntroductionThe refractory metal silicides have been playing an important role in the scaling downof integrated circuits to feature size of less than 2 um because of the low resistanceinterconnects and controlled metal -silicon interface reactions for both schottky and ohmiccontact.The bulk of the research to date has been Carried out in thermal equilibrium furnacereactions and both the film deposition and furnace annealing processes have been discussedin deteil along with characterized techniques in a lot of literatures.(1) The certain limi-tations have been found inAthe furnace thermal annealing because of longer time. In therecent years the rapid thermal annealing has been widely investigated. Laser(2), electronbeam(3), incoherent light(4) and ion beam mixing(5) have been used in this area. The mainfeatures offered by electron (and laser) beam processing are shorter reactin time localizedheat -treatment and rapid heating and cooling rates and thus, will minimize the dopantredistribution.Some results about metal silicon reaction induced by CW Scanned Laser and electron beamhave been reported (2) (3) (6) and these are related to the reactions of thin metal filimsdeposited by electron beam evaporation onto single crystal silicon substrates.In this paper, the properties and structures of tantalum and niobium silicides formedby scanning Electron Beam annealing have been investigated. The thin layers of tantalum andsilicon niobium and silicon are deposited by co- sputtering system and doulle E -beamevaporating system which are widely used in industry of integrated circuits, respectively.The uniform, essentially single phase silicides films are obtained with the scanned cwelectron beam. X -ray diffraction analysis Mev Ratherford backscattering spectrum andTransmission Electron Microscope have been utilized to characterize the structure of thefilms and the four probe equipment have been used to measure the electrical properties ofsilicide films. The results have been compared with those of furnace thermal annealing.ExperimentsThin layers of niobium and silicon were evaporated on silicon substrate using a doubleE -beam evaporation system (Type UMS -500 Balzers co.) with deposition rate = 3R /sec. in4 x 10-8 Torr pressure. During the evaporating the substrate temperature was keeped at108 °C. The thin layers of tantalum and silicon were also deposited on silicon wafers by Co-sputtering system (PERKIN ELMER 4450). The stochiometry and thickness of films weredetermined by Rutherford backscattering spectrum analysis. The total deposition filmthickness was found to be 2500X. The ratioes of silicon to niobium and silicon to tantalumwere found both to be 2.4.The Scanning Electron Beam (SEB) equipment was used to realize the rapid annealing toform niobium and tantalum silicides. The method of forming a quasi -linear source is tosynthesize a line by scanning a spot source with high speed