Windows of traditional wide band gap photodetectors are limited by the band gap of the semiconducting material used. In order to address this issue, the photoelectric properties of a plasmonic hot-electron phototransistor were fabricated and investigated. We have developed a plasmonic hot-electron phototransistor using a heavily doped silicon wafer as the back gate and insulating layer. Gold nanoparticles (AuNPs) were fabricated on the surface of the insulator via thermal annealing and the plasmonic hot-electron indium gallium zinc oxide (IGZO) phototransistor was developed. We investigated the optical and electrical properties of the phototransistor. The results revealed that the presence of AuNPs increased the photocurrent by a factor of 2.2 under a gate voltage of 90 V as compared to the IGZO phototransistor without AuNPs. The plasmonic hot-electron structure can effectively adjust the spectral response range of the phototransistor. Regulation of the back gate voltage was observed to amplify the photocurrent and improve the quantum efficiency of the device.

Path length control mirrors (PLCM) are important devices used to keep the cavity length of ring resonators stable. The deformation caused by the temperature variation directly affects the optical path shape and beam quality of ring resonators. In this paper, a finite element simulation model of PLCMs was established using ANSYS. Subsequently, the model was used to analyze the temperature and coupled fields of a PLCM under different temperature conditions. The deformation distribution in the middle of the mirror was obtained. Next, the accuracy of the finite element model was verified by sweep and temperature experiments, with an error of less than 2.5%. Finally, the deformation in the middle of the mirror under the variable temperature conditions was studied, obtaining the relationship between the deformation and the temperature. The influence of the thermal conductivity, Young 's modulus, and linear expansion coefficient of each component of the PLCM were simulated and analyzed. For different material parameters, the thermal conductivity and density have little effect on the deformation, while the Young's modulus and linear expansion coefficient greatly influence the deformation. The deformation was found to be inversely proportional to the Young's modulus and proportional to the linear expansion coefficient. In this paper, the temperature and the coupled fields of the PLCM under normal, high-low, and variable temperature were studied for the first time. In addition, the influence of the material parameters was quantitatively analyzed. The results of this paper have a guiding significance for material selection and optimization of PLCMs.

In order to further improve the efficiency of laser direct writing (LDW) in Cartesian coordinates, the exposure process was proposed to proceed in the accelerating and decelerating sections of the scanning stage, while the exposure effect was guaranteed by the following two ways. The pixel exposure data stored in a line buffer were clocked out by the position feedback pulses during the line scan, driving the acousto-optic modulator to obtain the corresponding beam intensity at the exact desired position. According to the kinetic characteristic of scanning stage, the necessary exposure data under uniform motion and minimum exposure intensity, and exposure data of each pixel in the accelerating and decelerating sections of the scanning stage, are modulated to make the distance of each displacement resolution in it exposed as much dose as that in uniform sections. Numerical simulations indicate that, considering an exposure pattern within a 5 mm × 5 mm area as an example, the total exposure time with the proposed method is 77.77 % of that with exposure only during the scanning stage moving at a constant speed. Meanwhile, the relative error of the exposure dose is increased from 04% to 10% when the bit of the acousto-optic modulator is decreased from 16 to 12.

MicroRNA (miRNA) is closely related to the occurrence and development of certain diseases and can be used as a diagnostic marker. Conventional methods for the detection of miRNA are time-consuming and complex. Herein, a portable rapid miRNA detection system was designed. This system records the fluorescence intensity of the marker that is amplified via rolling circle amplification using a photoelectric detection technique, and analyzes the fluorescence data to obtain the changes in miRNA. Through our experiments, we observed that for reagent concentrations in the range 0.1-1 μmol, the linearity of the fluorescence intensity detected by the miRNA fluorescence detection equipment was less than ±5%, and the repeatability was ≥95%. Our roll amplification experiment involving the coronary heart disease diagnostic marker, miR-499, confirmed that the portable rapid miRNA detection system can detect miRNA quickly and effectively.

Accurate prediction of the atmospheric turbulence evolution in the next few sampling cycles can compensate for the time delay in the control systems of adaptive optics (AO) systems. In this paper, a predictive correction method in AO systems is proposed, and its robustness is analyzed. Under the frozen-flow assumption, the translational motion can be identified using the slope measurements of a Shack-Hartmann wavefront sensor (SHWS) in AO systems. Using the transverse wind information, prediction of the future slope can be achieved by Fourier translation. The shape of the deformable mirror (DM) can be calculated by the direct-gradient wavefront reconstruction algorithm. The aberrated wavefront is corrected by the DM. With a known transverse wind, the proposed predictive correction can provide a perfect compensation for the decline of the dynamic performance caused by delays in the control system. With estimated wind parameters, improvement of the correction efficiency can be obtained as long as the wind-velocity estimation error is less than the velocity itself, while the wind direction is estimated accurately, or the direction error is less than 60° while the wind speed is estimated accurately. With a simultaneous wind-velocity and direction error, the correction efficiency can still be improved within a large error range.

In order to realize small deformation measurements of Numerical Control (NC) machine tool structures and micro-processing platforms, a high-precision optical fiber Bragg grating (FBG) micro-displacement-sensor based on a bow shape was designed. The grating region of the FBG was attached to the upper and lower walls of the bow. Hence, the strain value of the upper and lower walls could be measured while the bow was deformed, allowing displacement measurement and achieving temperature decoupling. Experimental results show that in the displacement range of 1 mm, the sensitivity by fitting a straight line is 2.02 pm/μm, the linearity is 2.92%, the linear correlation coefficient is 0.998 3, the hysteresis error of three groups is 4.08 %, and the repeatability error of three groups is 4.08%. A temperature compensation test is presented in addition, showing a wavelength drift of less than 1 pm with a temperature increase of 1 °C. Furthermore, a similar half bow structure was derived and compared with the previous bow type in terms of their performance. The comparison shows that the temperature compensation of the bow type is 0.001 5 pm/μm, which is smaller than that of the half bow type, while the latter has a better static calibration linearity of 04%. It satisfies the sensor requirements of stability, higher precision, as well as strong electromagnetic interference resistance and temperature insensitivity.

A novel method of Bayesian adaptive estimation was proposed to improve reconstructed slice images based on a photon-counting integral imaging system for three-dimensional (3D) targets in a photon-starved environment. First, a series of photon-counted elemental images were obtained by a photon-counting integral imaging system. Subsequently, based on the Poisson distribution of the photon-counting process, the posterior probability model for photon estimation of the elemental images was established with one local adaptive mean value introduced. The model benefits from the feature of multiple sampling for the same reconstructed voxel by the integral imaging system. Finally, the photon-counted elemental images were updated by calculating the expected value of the posterior probability model and the depth slice images were reconstructed by back-propagating the captured light rays. Experimental results show that the peak signal-to-noise ratio of the depth slice images reconstructed by the proposed method can be 7.4 dB and 8.5 dB higher than that of conventional Bayesian estimation at two scene depths, which greatly improves the quality of 3D target reconstruction.

To realize biodetection based on Raman scattering of semiconductor under visible light excitation, the Raman probe was constructed by using MoS2 material, a narrow bandgap semiconductor, to realize high specific recognition of the human IgG molecule. First, MoS2 and WS2 micromaterials were obtained by liquid-phase exfoliation method. The effect of temperature on the intensity of the Raman signal excitated by a 532 nm laser was analyzed through heating and aging treatment. Second, the carboxyl group was introduced to the surface of the MoS2 material by 3-mercaptopropionic acid modification, and a Raman probe was obtained. Finally, the performance of the MoS2 based immunoassay was evaluated by using a sandwich structure of "antibody-analyte-antibody". It was found that the heating and aging treatment at appropriate temperature enhanced the Raman scattering intensity of the transition metal disulfide (70 ℃ is the optimal). The results of control groups show that the Raman intensity of the immunodetection increased and saturated with the concentration of the human IgG. The detection limit is 1 fM. The current procedure realized immunoassays with high sensitivity and high specificity by using the Raman scattering of semiconductor under visible light excitation.

Modern ships are usually redundantly equipped with one-axis indexing ring laser gyro (RLG) marine inertial navigation system (MINS) and several two-axis indexing RLG MINS. In order to online evaluate the relative performance of the redundant two-axis indexing RLG MINS, an online evaluation method based on joint rotation and modulation was proposed without using external benchmark information. Several joint error Kalman filters were constructed. The system states of each Kalman filter included the position error differences, the velocity error differences and the attitude error differences between the one-axis indexing RLG MINS and corresponding two-axis indexing RLG MINS, as well as the gyro drifts and horizontal accelerometer biases. With the position and velocity difference between the systems being observations, the observability analysis showed that all states including azimuth gyro drift of the one-axis indexing MINS were observable if the relative attitude between the systems was changed by the joint rotation and modulation. The azimuth gyro drift estimation standard deviation of the one-axis indexing MINS were defined as the assessment criteria to online evaluate the random errors of the two-axis indexing MINS. The semi-physical simulations and the experimental results show that the RLG random error difference of the two-axis indexing MINS can be distinguished at a level of 10% noise and the position accuracies of different two-axis indexing MINS are online evaluated according to the azimuth gyro drift standard deviation of the one-axis indexing MINS during 144 h navigation time. The proposed method provides theoretical basis for optimum system choosing in the case of one-axis and two-axis indexing RLG MINS redundant configuration.

To manufacture curved surface gratings with highly consistent blazing angles, the curve-fitting motion of the three-dimensional (3D) stage is essential. Therefore, an investigation of the 3D stage was performed based on a control algorithm for the curved blazed grating etching system. First, a concept of the 3D stage of the curved blazed grating etching system was introduced. Subsequently, according to the actual requirement of the etching machine, the theoretical calculating method for the track of the stage was provided. Then, the arc-fitting algorithm of the stage was proposed and the curve-fitting motion of the stage was performed. Finally, the actual motion tracks of the 3D stage were measured and compared with ideal tracks. Experimental results demonstrate that the cumulative positioning error of the linear fitting motion of the stage after 15 cycles is less than 0.218 mm, and the slope angle error is less than 0.02°; the cumulative positioning error of the curve fitting motion of the stage after 40 cycles is less than 0.2 mm and the rotating angle error is in the range of -0.2°-0.1°. This method has realized the function of scanning etching and oscillating etching of the 3D stage. The stability, accuracy, and interference rejection of the stage satisfy the processing requirements.

To avoid the negative effects of structural parameters′ randomness on its properties, an optimization method of locking elastic sheet based on reliability sensitivity was proposed. Firstly, the finite element model and failure modes of the locking elastic sheet for a magnetic suspension control moment gyro were analyzed. Afterwards, considering the randomness of the structural sizes and material parameters of the elastic sheet, the reliability of the elastic sheet in the series failure mode were studied by using the response surface method and the first order second moment method. Furthermore, the calculating formulas of reliability sensitivity with respect to the mean and variance of random variables were derived. Eventually, the model of elastic sheet reliability optimization was built with the optimization strategy determined by the result of reliability sensitivity analysis. The difference influence of safety factor optimization and reliability optimization was analyzed. Experimental results indicate that the reliability optimization could get better optimization results compared with the safety factor optimization. The reliability sensitivity optimization method not only reduces the weight of the elastic sheet by 23.71% under the premise of ensuring the high reliability of the elastic sheet, but also reduces the weight of gyro room by 0.98 kg, which is beneficial to weight reduction of the magnetic suspension control moment gyro.

To implement reliable locking under launching mechanical environment and low-impact and fast-response unlocking on-orbit for the CubeSat “Star of Aoxiang”, a non-pyrotechnic door release mechanism was proposed which locked by reset spring at the time of power off and unlocked by electromagnetic force at the time of power on. Firstly, according to the system requirements, the work principle of electromagnet door release mechanism was introduced, and the coupling dynamical models involving mechanical-electrical-magnetic characteristics were established. Secondly, the multi-constrain and multi-objective problems of electromagnet parameters were solved based on the ground tests, after that, the simulation verification of the optimized parameters was implemented. Then, the functional tests for a prototype of the electromagnet door release mechanism were carried out. The measurement values agreed well with the simulations results, which showed that the unlocking time was 41.2 ms and the current was 2.2 A and the energy consumption was only 2.5 J at the typical voltage of 28 V. Finally, on the condition of mechanical and thermal-vacuum ground environment and down-deflection of ±5 V, the electromagnet door release mechanism could lock and unlock reliably. The proposed door release mechanism has successfully applied to unlocking and launching the CubeSat “Star of Aoxiang” on-orbit. It provides reference for further standardization design of door release mechanism for following CubeSats and other micro-satellites.

In order to improve the accuracy of the servo system at low temperature, the mechanism that the load torque of the telescope increase along with the temperature decrease must be deeply understood. Firstly, the influence factors of friction torque of bearing and the influence of low temperature on load torque were analyzed. The lubricant viscosity with temperature variation was studied. The relationship between load torque and grease was tested and discussed. The results indicate that the fluctuation of load torque without the grease at low temperature is decreased and the linearity of load torque is increased. The influence of clearance on bearing friction torque was also analyzed. The expansion coefficient of different materials at different temperatures was measured by resistance strain gauge method. The correlation coefficient between torque and material expansion was established. The result indicates that the load torque at low temperature is 6.67 times load torque at normal temperature, and the maximum of shortening of material reaches 960 με. The research on the mechanism of cryogenic load torque in this paper can provide theoretical and experimental data for the precise control of the telescope under extreme environment.

In order to obtain the optimal structural parameters of the absorption cavity of Solar Irradiance Absolute Radiometer(SIAR), a study was carried out on the thermal circuit of the SIAR, which was constituted of the cavity, thermal link and heat sink. Based on the finite element method by using Ansys software, a reliable model of this thermal circuit was introduced. The temperature response curves of the model were consequently obtained. Then the effects of structural parameters of the cavity, e.g. sizes and materials were investigated on the SIAR's thermal performances, and optimal structural parameters of the cavity were proposed. Simulation results indicate that at the ambient temperature of 298 K and heating power of 50 mW, the optimal parameters of cavity are silver with a wall thickness of 0.07 mm, a cone angle of 30° and a brim width of 2.2 mm, and when the thermal time constant is 11.501 s, the responsibility is 1.391 K. Experiments are carried out under the same conditions: the time constant and responsibility of measurement are 11.487 s and 1.397 K. Compared with simulation results, the differences are 0.12% and 0.43%, respectively. The simulation results are in accordance well with the theoretical derivation, and the results are sufficiently reliable, so that this model can be used to conduct the optimation design of the absolute radiometer and improve its performance.

This paper aims to explore the brittle fracture characteristics and fluctuation behavior of cutting force during scratch process of RB-SiC with different scratch depth and indenter shapes. The diamond Berkvoich indenter with 400 nm and conical indenter with 8.7 um were used to conduct experiments under constant scratch depth mode. Then, the surface morphologies and brittle fracture behavior were observed with a scan electron microscopy (SEM). Finally, Daubechies wavelet was adopted to decompose the lateral and tangential forces, and the relationship between different detail signal/decompose signal and damage types were given. The results show that with the increasing of scratch depth, plastic extrusion, micro fracture and large area fracture are coexist when conical indenter is used. Besides, the degree of fracture is more serious and cutting force signal energy spread from low-frequency to the whole frequency with the decrease of indenter radius and the energy of low-frequency band energy gradually occupied the dominates position. Surface and margin microfracture make the dominate contribution to the detail signal of cutting force. Scratching force fluctuation energy is mainly come from the structure difference and defects of RB-SiC which caused mass crushing, and increased with scratch depth.

According to the urgent needs of active flexibility of equipment in a wide variety of industry sectors, such as precise assembly, removing, shaving, grinding, polishing and scrubbing on the surface of workpiece, an active constant pressure output device based on a cylinder was designed. According to design goals, it made a specific choice of the devices (including proportional pressure regulator, cylinder, guide rail, pressure sensor, etc.) which were used. And a weak signal conditioning circuit was designed for the pressure sensor, which can enhance the accuracy and anti-interference ability of the signal. And also, a data acquisition and processing board was designed to control the whole system and realized closed loop control of force output. And it received command of the host computer and uploaded the collected data through the RS485 communication. Finally, through a large number of dynamic and static pressure tests, it was shown that the output force error of the equipment is within ±3 N, the response time is less than 300 ms, the output force is greater than 200 N, and the performance meets the design goals. The development of this device opens up a new way for the design and research of active force control system.

In the digital Polymerase Chain Reaction(dPCR) detection process, discriminating positive droplets from negative ones directly affect the final concentration, which is one of the important factors affecting the accuracy of the instrument. Current methods do not take into account the influence of sample concentration on the result error, resulting in a larger deviation from the actual results at a low concentration. In this paper, a florescent droplets classification method was designed based on generalized Pareto distribution. It was discussed that the possible effects of misclassification at different concentrations on the results, determined the high quantiles of generalized Pareto distribution, and verified the proposed method on the self-made droplet digital PCR. Experimental results showed that for the method proposed, the linear regression of samples with target copies from 5 to 5 000 got an r2=0.995 6 and a detection limit of less than 5 copies/samples, while that of the comparison method was less than 50 copies/sample. These results indicate that the proposed method improves the lower detection limit of the droplet digital PCR by oneorder, and can achieve automated droplet classification at ultra-low concentration.

In order to enhance the ability of disturbance rejection for the telescope, and improve the tracking accuracy of the telescope mount control system, this paper analysis the dynamic of mount control system for the two meters telescope. Firstly, the frequency response of telescope mount control system is test using swept sine. Secondly, the Observer/Klaman filter algorithm is employed to identify the model for the mount control system. Finally, the position controller and speed controller are designed based on the mount control model. The experimental results of target observation show that max tracking errors of the azimuth and elevation axis are less than 4.5", and the tracking error RMS are 0.378 6" and 0.151 6", when the target moving with the max speed 3.5 (°)/s and the max acceleration 1 (°)/s2. The experiments verify the good dynamic of telescope mount control system.

To increase the imaging rate of atomic force microscope (AFM), a new AFM structure design was presented. In this structure, the Y and Z scanners were integrated in the scanning head, which move the probe in the slow-axis and the Z-axis, respectively. The X scanner was separated from the head, which moved the sample in the fast-axis. An independent one-dimensional nanopositioning stage was used as the X scanner. Due to its high stiffness, the X scanner could carry relative large samples and scan at a high speed without inducing resonance vibration. Meanwhile, the load of the Z scanner was minimized, resulting in higher resonant frequency and hence faster response. A trackable optical lever was used to avoid the shift of the laser spot on the cantilever probe during scanning. A magnetic based probe holder as well as a new adjustment setup were introduced to hold the probe and precisely position it relative to the laser. According to a preliminary test, the AFM system established in this work can realize high speed imaging for the sample with centimeters dimensions and mass above 10 g. The scanning speed (line frequency) achieves 50 Hz@13 μm with linear driving and simple PID control algorithm.

Polymer microfluidic chips have high requirements for bonding precision, bonding strength and bonding efficiency. In order to avoid the clogging of microchannel by fusion and solve the problems of low bonding strength, uneven pressure distribution caused by leveling precision and high-frequency vibration in the process of ultrasonic bonding, the joint structure and self-balancing jig were designed and fabricated. First, based on the self-balancing jig and conventional jig with no leveling function, the pressure distribution coefficient was defined and measured by prescale film. Moreover, the chips we designed were bonded with two types of jigs respectively. The bonding line and cross-section of microchannels were measured by measuring microscope. Last, these chips were tested by electric tensile tester and sealing test. Experimental results indicate that the precision of controlling microchannel can reach about 2.0 μm. The self-balancing jig can improve pressure distribution about 35.20%-43.18% with simple structure and easy operation, and make the bonding line uniform. The bonding strength increases about15.3%-45.1% with excellent sealing performance. It concludes that the joint structure and self-balancing jig can satisfy the requirements of controlling precision, bonding strength, pressure distribution and sealing performance.

In order to reconstruct the digital contour curve with arc and straight line, a method was proposed to integrate the segmentation of digital contour curve based on the slope difference judgement method and the dynamic segment merge method. First, the slope difference between the front and back directions of each point on the contour curve was calculated using straight line fitting. The process of obtaining the slope difference used the adaptive length fitting window to balance the relationship between the precision and the velocity. Then the adaptive smoothing method was applied to the direction slope difference curve. Based on the smooth slope of the slope curve, the intermittent point was extracted as the selected section segmentation point. Finally, a dynamic merge algorithm based on the perceptual error was used to select a segmentation scheme with the smallest perceptual error from the selected segments as the final result. The simulation results show that the error of this segmentation method is less than 1%. The experimental results of the contours of bearing oil groove as the actual test cases show the feasibility of this adaptive contour segmentation method in practical application.

In order to eliminate the effect of echo outside the field of view (FOV) on fringes scanning imaging (also known as Fourier telescope or coherent field imaging), this paper analysed in theory the main factors of reconstruction overlap caused by echo, and provided the best solutions to different application scenes. This paper studied in detail the effect of echo from different illumination zones on imaging by means of computer simulation and also analysed in detail the improving effects of the scheme of adding short baselines on reconstruction blur. The results of simulation show that the echo from three beam (the largest number of beams transmitted simultaneously) overlap zone has the most serious effect on reconstruction results and that adding short baselines can eliminate image overlap and also that the more short baselines are added, the more distinct details can be got(one short baseline can promote the Strehl ratio from 0.49 to 0.59). The schemes of eliminating effect of echo outside the FOV provided by this paper could be useful to the concrete implement of fringes scanning imaging in different application fields.

In order to improve the accuracy of water area segmentation in high resolution remote sensing image, the image entropy was introduced into CV model because there was a quite difference of texture complexities between water area and background, and two active counter models based on image entropy were proposed in this paper. The image entropy of inside zero level set was adopted in CV model and forms a local image entropy active counter model (LIEACM). This model effectively reduced the incorrect segmentation of background where the gray value approximated to the water area with low texture complexity. For remote sensing image of water area with high texture complexity, the global image entropy active counter model (GIEACM) was proposed, in which, the image entropy of inside and outside of zero level set were employed in CV model simultaneously. GLEACM modifies the fact that the level set function evolution depends on gray value, and the zero level set cald evaluate to the global optimal value. The experiments on segmentation the lake, river and sea validate that the segmentation precisions of LIFACM are 90.1%, 81.5% and 93.6%, respectively, the F-measures are 0.94, 0.885 and 0.96, respectively; and for GLEACM, the segmentation precisions are 94.5%, 853% and 94.9%, respectively, the F-measures are 0.956, 0.895 and 0.967, respectively. The two image entropy active contour models proposed by this paper improve the water area segmentation accuracy in remote sensing image effectively.

Different from traditional cameras, light field camera sets a lenslet array between the main lens and the sensor at a specific position, which makes it possible to record the light intensity and the direction of light rays at the same time. In order to reconstruct the object-side light field, the reconstruction algorithm of the focal planes based on the light field camera was studied. Focal stack and projection slice theorem used in the algorithm was researched. Firstly, parameterized 4D light field definition and the working principle of light field camera were analyzed. Secondly, the depth reconstruction model of the camera was established and research the application of the projection slice theorem in getting the focal planes and then Derived the expression of the different focal planes images. Finally, according to the different focal planes images, the computational reconstruction algorithm was studied to realize the reverse reconstruction of the object-side light field. A micro light field camera was built contains lenslet array, collected the original light field, reconstructed the object light field by the method in this paper.The results show that the light field collected by light field camera can be filtered reverse reconstruction of the method proposed in this paper, the depth and the surface of object can be further reconstruction via the light field data. The focal planes images acquisition algorithm in this paper saves more than 30% time compared with other algorithms, and the Peak Signal to Noise Ratio of each focal plane image is between 25-30 dB, which meets the requirements of high precision, stability, reliability and fast speed of light field reconstruction.

This work extended sparse decomposition (SD) into quaternion space in order to find a better sparse representation for acoustic vector array (AVA). A novel sparse decomposition algorithm based on the well-known orthogonal matching pursuit (OMP) for quaternionic signals was proposed and it was used to solve the question of direction of arrival (DOA) estimation of AVA in small snapshot number, coherent signal source and low signal noise ratio (SNR) case. Compare with the complex field SD algorithm, The results illustrate that the atomic length of the over-complete dictionary is reduced to one-third of that from the long vector model, while errors in DOA estimation are effectively eliminated using the long vector method when the true angles of DOA estimation lie within 1°. Simulation results verify the validity of this algorithm.

In this paper, a fast and accurate ship target detection method wa proposed for ship detection in optical remote sensing image. The “coarse-to-fine” strategy was applied, which contains mainly three stages: the candidate regions extraction, building the candidate regions’ descriptor and the candidate regions discrimination by reducing the false alarms to confirm the real ship targets. In the first stage, first the initial saliency map was extracted by the maximum symmetric surround method, which was based on the visual attention mechanism, and updated according to the local similarity via a updating mechanism of cellular automata; then, the final saliency map was segmented by OTSU algorithm to obtain binary image; finally salient regions were extracted from the segmented binary image, and filtered roughly by the ship objectives' geometric features. In the second stage, a new descriptor, named edge-histogram of oriented gradient (E-HOG), was proposed to describe the ship target. The E-HOG feature was an improvement of the traditional HOG feature, based on the inherent characteristics of the ship targets. Compared to the traditional HOG feature, the E-HOG feature limited the statistical scale into the edge of the salient regions, for the purpose of reducing the influence of the variability of oriented gradient, and reducing computation complexity. On one hand, the descriptor could discriminate the ship objectives from others like cloud, islands and wave; on the other hand, the descriptor was insensitive to the size of the ship objectives, which reinforce the robustness of the approach. In the third stage, the AdaBoost classifier was used to confirm the real ship targets by eliminating the false alarms. We intercept 517 positive samples and 624 negative samples from the remote sensing images to train the AdaBoost classifier. The size of these training samples ranges from 20 pixel×10 pixel to 200 pixel×120 pixel, where the positive samples include different types of ship targets, and the negative samples include non-ship targets such as clouds, islands, coastlines, waves and sea floating objects. In this paper, the detection time is 2.386 0 s for the 1 024 pixel× 1 024 pixel remote sensing image, the recall rate is 97.4%, and the detection precision is 97.2%. Experiments demonstrated that the detection performance of the proposed method outperforms that of the state-of-the-art methods, and it can meet the actual engineering requirements in the detection time and detection precision.

Aiming at the problem of precise alignment of industrial arm, an industrial robot alignment method based on monocular vision is proposed. Combining the industrial robot with monocular vision measurement and a specialized hand-eye calibration panel, the method is able to quickly establish the hand-eye relationship between the camera coordinate system and the alignment axis on the robot's end-effector. In the alignment stage, the attitude of the workpiece is obtained by monocular vision system, and then according to the existing hand-eye relationship and datum posture, the position and orientation between the alignment axis and the workpiece of the alignment axis are evaluated. The experimental results show that the average precision of the alignment is better than 0.2° under the measuring distance of 150 mm.