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Background Gastric outlet obstruction (GOO) is a late complication of advanced gastric cancer, and it is controversial how to select the therapeutic strategies: gastrojejunostomy and palliative gastrectomy? Therefore, this study was to compare the surgical and survival outcomes of gastrojejunostomy and palliative gastrectomy. Methods In total, 199 gastric cancer patients with outlet obstruction treated by surgery between January 2000 and December 2015 at Sun Yat-sen University Cancer Center were retrospectively reviewed. Patients were divided into gastrojejunostomy group and palliative gastrectomy group. Propensity score matching (PSM) was performed to balance the selection bias. Results After 1:1 PSM, a total of 104 patients were included for final analysis. The median overall survival (OS) times in the gastrojejunostomy group and palliative gastrectomy group were 8.50 and 11.87 months, respectively (P = 0.243). The postoperative complication rates in the gastrojejunostomy group and palliative gastrectomy group were 19.23% (10/52) and 17.31% (9/52), respectively (P = 0.800), and no treatment-related death was observed. Multivariate analysis showed that periton0eal seeding (P = 0.014) and chemotherapy (P Conclusions Our results indicated that although the surgical complications of palliative gastrectomy were manageable, it showed no survival benefit. Therefore, relieving obstruction symptom, improving patients’ quality of life and creating better conditions for chemotherapy appear to be the main therapeutic strategies for advanced gastric cancer with GOO.

Airway tree segmentation plays a pivotal role in chest computed tomography (CT) analysis tasks such as lesion localization, surgical planning, and intra-operative guidance. The remaining challenge is to identify small bronchi correctly, which facilitates further segmentation of the pulmonary anatomies. A three-dimensional (3D) multi-scale feature aggregation network (MFA-Net) is proposed against the scale difference of substructures in airway tree segmentation. In this model, the multi-scale feature aggregation (MFA) block is used to capture the multi-scale context information, which improves the sensitivity of the small bronchi segmentation and addresses the local discontinuities. Meanwhile, the concept of airway tree partition is introduced to evaluate the segmentation performance at a more granular level. Experiments were conducted on a dataset of 250 CT scans, which were annotated by experienced clinical radiologists. Through the airway partition, we evaluated the segmentation results of the small bronchi compared with the state-of-the-art methods. Experiments show that MFA-Net achieves the best performance in the Dice similarity coefficient (DSC) in the intra-lobar airway and improves the true positive rate (TPR) by 7.59% on average. Besides, in the entire airway, the proposed method achieves the best results in DSC and TPR scores of 86.18% and 79.31%, respectively, with the consequence of higher false positives. The MFA-Net is competitive with the state-of-the-art methods. The experiment results indicate that the MFA block improves the performance of the network by utilizing multi-scale context information. More accurate segmentation results will be more helpful in further clinical analysis.

Rectification is a critical process for speckle projection systems to ensure reliable image matching in producing a depth map. However, few studies have discussed it up to the present. In this article, we present a flexible but robust approach to address this issue. It mainly consists of two steps: calibration and rectification. The calibration step takes one or several pairs of images of the projected speckle pattern on a plane to estimate a unit vector indicating the direction of the line where emitter center lies on. The rectification step virtually rotates the camera based on this vector to obtain rectified images. Given camera intrinsic parameters, this approach only needs a minimum configuration consisting of two freely captured speckle images of a planar surface to complete system rectification, which makes it particularly suited for the case with no access to the internal projected speckle pattern. Elaborate experiments on real speckle images and synthetic images from different camera poses are conducted, demonstrating the effectiveness and robustness of the proposed approach. Furthermore, we also demonstrate that when the internal pattern is recovered from the rectified images, it reaches an accuracy comparable with the ones from the best state-of-the-art methods in performing a stereo matching, but with a much simpler operation to obtain.

In view of the problem of misjudgment of switch state image recognition in substation, this paper proposes a method of substation switch image recognition based on the Non-Subsampled Shearing Transform (NSST) image fusion. According to their characteristics and complementary relationship, the visible image and infrared image are fused based on the NSST image fusion algorithm, and the fused image containing rich details and contour features of the two switch source images is generated. The improved Speeded Up Robust Features (SURF) algorithm is used to extract and match the target features of the fusion image, and then the multi threshold image segmentation technology based on the Chaotic Cuckoo Search (CCS) algorithm is used for processing. Finally, the slope of the line where the switch arm and two contacts are located is obtained based on Hough transform, and the switch state is judged according to the angle difference between them. Simulation results show the reliability of the proposed method.

Lung tissue segmentation is vital in computer-assisted diagnosis, and many studies have been devoted to this field. However, there are still challenges because of redundant information in CT images and the deformation of organ tissue. In this study, we constructed a fully convolution neural network-based model called LTS-Net to segment lung tissue from CT images. First, to improve efficiency and guarantee segmentation accuracy, the network model uses three downward max-pooling layers and three up-sampling layers. The number of convolution channels increases exponentially with each down-sampling step, thereby resulting in fast feature extraction. Furthermore, each convolutional layer follows an ReLU and a batch normalization layer to maintain robustness. Finally, we analyzed the influence of the receptive field size for lung tissue segmentation to provide a trade-off between accuracy and efficiency. To evaluate the performance of LTS-Net, we constructed a CT image dataset at West China Hospital of Sichuan University. The results demonstrated the constructed model's performance: LTS-Net obtained a new state-of-the-art result of 0.992 Dice coefficient on the dataset.

Background Cluster headache (CH) refers to the most painful primary headache that sometimes leads to poor quality of life and associated disability. So far, no treatment has been found to cure CHs. In this study, we introduce a novel and effective surgery for CH. Methods We studied 6 patients with CH diagnosed according to the criteria of the Headache Classification Committee of the IHS, third edition, who were eligible for surgical treatment on the basis of strong requirements. All of them underwent temporal craniectomy and transection of the greater superficial petrosal nerve and deep petrosal nerve pathway to the sphenopalatine ganglion. Results All 6 patients had the surgery for CH and follow-up per 3 months. We significantly cured their pain and autonomic dysfunction. In the follow-up process none of the patients had reoccurring alacrimia. All of them had reduction of secretion of nasal, oral mucosa, and parotid and were satisfied with the surgery. Conclusions All 6 patients with CH received surgery by transection greater superficial petrosal nerve and deep petrosal nerve pathway to the sphenopalatine ganglion and were completely cured, and adverse events and serious complications did not occur.

In this study, targeted at dead zone in supervision of new aluminum-alloy-core aluminum conductor when applied in hardware crimping fabrication, a quality detection method for line hardware was proposed based on ultrasonic flaw detection technology and laboratory verification of ultrasonic detection of the conductor crimping depth was performed. An ultrasonic on-site inspection program was presented, and the effect of ultrasonic flaw detection technology on line crimping quality inspection was demonstrated with an engineering application example.

Photovoltaic power generation is affected by weather and geographical environment, showing fluctuations and random multi-interference, and its output power is easy to change with changes in external factors. Therefore, the prediction of output power is crucial to optimize the grid-connected operation of photovoltaic power generation and reduce the impact of uncertainty. This paper proposes a hybrid model of both convolutional neural network (CNN) and long short-term memory neural network (LSTM) based on genetic algorithm (GA) optimization (GA-CNN-LSTM). First, the CNN module is used to extract the spatial features of the data, and then the LSTM module is used to extract the temporal features and nearby hidden states. Optimizing the hyperparameter weights and bias values of the LSTM training network through GA. At the initial stage, the historical data is normalized, and all features were analyzed by grey relational degree. Important features are extracted to reduce the computational complexity of the data. Then, the GA-optimized CNN-LSTM hybrid neural network model (GA-CNN-LSTM) is applied for photovoltaic power prediction experiment. The GA-CNN-LSTM model was compared with the single neural network models such as CNN and LSTM, and the CNN-LSTM hybrid neural network model without GA optimization. Under the Mean Absolute Percentage Error index, the GA-CNN-LSTM algorithm proposed in this paper reduces the error by 1.537% compared with the ordinary single neural network model, and 0.873% compared with the unoptimized CNN-LSTM hybrid neural network algorithm model. From the perspective of training and test running time, the GA-CNN-LSTM model takes a little longer than the single neural network model, but the disadvantage is not obvious. To sum up, the performance of GA-CNN-LSTM model for photovoltaic power predicting is better.

Capacity analysis is a hotspot in the research of wireless networks, playing an important role in the network construction. This paper analyzed the connectivity of the network to form the hops-distribution probability formula between the source node and the destination node; then developed the closed-form expressions of the upper bound and lower bound of the multi-hop capacity based on the Gupta physics model; finally first-order energy model was built for computing the bounds of the lifetime of the networks. This paper defined capacity as the amount of traffic in the lifetime of the networks. The numerical simulation shows: multi-hop network capacity with the node number showed a trend of first increasing and then decreasing; with the increasing of nodes, multi-hop have the high probability in transmission and larger range of capacity than that of one-hop network.

The capacitor voltage transformer (CVT) is a potential transformer (PT) composed of capacitive voltage divider and electromagnetic unit. In high voltage classes, the capacitor voltage transformer has the advantage of simpler structure and lower cost in comparison with electromagnetic potential transformer (PT), so potential transformers with voltage class of 220kV and above are CVT basically. Transformer acts as an important link of power trade measuring system, and its accuracy is directly related to the justness and fairness of power trade. CVT at transformer substation is usually installed outdoor and often runs in different natural environments, while periodic detection is adopted for CVT, but there is no relevant research on the impacts of CVT error characteristics from the natural environment during actual operation. In this paper, online monitoring system is used to compare a good-stability bus with line CVT, taking PT as standard, so as to research the CVT error characteristics in actual operation cases. As the result indicated, ratio error and angle error of the CVT present regular changes within 24h, two extreme inflection points of the ratio error respectively occur at 6:00 a.m. and 4:00 p.m., representing shifting towards negative values, similar phase errors, but no out-of-tolerance.

Actual operation showed that the measurement error of capacitive voltage transformer (CVT) was influenced electric field. To study the error characteristic of CVT causing by external electric field, the paper established simulation model by using finite element simulation software (Ansoft Maxwell 14.0). The simulation results indicated that the measurement error increased gradually with the increase of the height (H) in a certain range. When the height(H) was beyond 4.5 meters, the measurement error was stable. When the distance(D) was less than 3.5 meters, the measurement error decreased. The error was linear with the voltage(U) of the object and the linearity was both related with distance (D) and height (H). The change in angle, diameter and length of high-voltage lead would also result in the change of capacitance of capacitive divider and bring errors.

For the output current distortion and larger harmonic of conventional PWM inverter, a predictive control method with minimum cost current is proposed. Based on the predictive control model of the inverter and load, the forecast current is calculated by the sampling current and predictive model. Furthermore, the optimum switching vectors with minimum cost and lower switching times can be got through the calculation of cost and switching times. Then we can realize the minimum current tracking error and switching loss of power device. The simulation results show that the proposed method is good to solve the output current distortion and larger harmonic of conventional PWM inverter. Meanwhile, the method provides a theoretical reference to further optimize the control of the power converter.

Vehicle-pedestrian collision is a major type traffic accident in China, which has been attracted close attention by people because of its high fatality rate. However, it is difficult for traffic management department to reconstruct such kind of accident. In this paper, a methodology for simulation of vehicle-pedestrian accidents based on the multi-body dynamics is presented. A multi-body dummy pedestrian model is established based on PC-CRASH programs, the features that represent the different parts of the pedestrian are defined such as geometry, mass, contact stiffness and coefficients of friction. And more the model is introduced to simulate the collision in a real case of vehicle-pedestrian accident in Hangzhou. Different impact speeds are discussed to predict the different throwing distance of the pedestrian. The relation curves and equations between pedestrian’s throwing distance and vehicle impact speed are established from regression analyses of the simulation data. Finally, the impact speed is estimated with correspond to the exact pedestrian throwing distance.

A Solar power controller is designed based on High Stability Microcontroller PIC18F97J60.The controller uses a serial SPI LCD as the display interface,the solar cell voltage and output current,load electricity consumption and the controller running state are displayed in the LCD screen.The controller can communicate with the host computer through an Ethernet.The hardware structure and software flow design of the Solar power controller has been given.The experiment proved that LCD module has the advantages of simple structure,strong anti-interference ability,better stability,and satisfied the requirement of real-time display of the solar power controller.

A simplified digital positron lifetime spectrometer is presented and tested. This system is only composed of two scintillation detectors, a time delayer and a digital oscilloscope. Both online and offline analysis of the detector signals can be optionally chosen to construct positron lifetime spectrum by histogramming the time difference between the positron birth signal of 1.27 MeV γ-ray and one positron annihilation signal of 0.511 MeV γ-rays. Several pulse discrimination methods and timing numerical algorithms are proposed and well applied to perform pulse energy discrimination and digital constant fraction timing (DCFT). A combination discrimination of pulse amplitude, pulse risetime and ratio of pulse area to pulse amplitude with DCFT is found able to achieve the best time resolution of 208 ps full-width at half-maximum (FWHM), which is much better over the analog spectrometer using the same detectors. This newly developed apparatus except for having better performance is particularly easy to be constructed and implemented.

To solve problems in aircraft manufacturing, flexible tooling system with “Forming-Machining” process is presented. Pointwise degree of freedom is defined on aircraft large-scale thin-wall workpiece during its machining process where traditional six-point location principle is not suitable, and base on which adaptive multi-point location method used for this kind of workpieces is described. Furthermore, multi-point location/support algorithm is developed to solve positions of location/support spheres of flexible tooling system to construct envelope surface of workpiece and avoid machine tool interference. Test data of sample workpiece show that flexible tooling system meets the requirements of aircraft large-scale thin-wall workpiece machining with manufacturing error and cycle decreased.

Neutron source has broad application prospects in crystallography, neutron irradiation, neutron therapy for cancer, and so on. As a new scheme to produce bright pulsed neutron source, the laser-driven neutron has attracted wide interest. In recent years, laser driven neutron sources have been extensively studied and the great progress has been made. Short pulsed laser driven neutron sources could be a compact and relatively cheap way to produce quasi-monoenergetic neutrons. The yields and the angular distributions of the laser-driven neutron sources are important in the research of laser-driven neutron sources and relevant applications. We conduct experimental investigation of this respect by using the XingGuang-Ⅲ high intense laser facility, which delivers synchronized picosecond and nanosecond laser pulses. The picosecond laser energy is 100 J, the pulse width is 1 ps, and the focusing spot diameter is 20 μm. At this time, the corresponding laser power density reaches 3×1019 W/cm2. A high-energy deuterium ion beam is produced by focusing the picosecond laser on a deuterated polyethylene foil, and the deuterium ion beam is incident on a secondary deuterated polyethylene planar target to activate the D-D reaction to obtain the neutron beam. In the experiment, the neutron yield and its angular distribution are measured by the different-sensitivity BD-PND bubble detectors, which are placed in the target chamber around the target. The emission of the neutron beam is found to be non-uniform. A maximum intensity of 5.13×107 n/sr is observed in the forward direction. The angular distribution of the neutron beam is theoretically calculated by taking into account the energy-angle cross section, the angular and energy distribution of the incident deuterium ion beam. The probability of the neutron energy-angle distribution in the laboratory system is obtained by the coordinate transformation from the probability in the center of mass frame. The results show good agreement with the experimental measurements. This experiment has a certain reference value in the practical application of D-D reaction neutron source.

In this paper, a polarization insensitive and wide angle metamaterial absorber based on the electromagnetic resonance was designed. The absorber consists of electrical metal ring resonator, lossy medium and full-metal film. We applied different polarization of vertical incident electromagnetic waves and oblique incident electromagnetic waves respectively on the surface of the absorber, and conducted an electromagnetic simulation on the structure. The results show that the absorption rates for different vertical polarization incident electromagnetic waves were 99.9%, which indicates that the absorber has a high absorption and insensitive-polarization. When the angle of incidence increases to 60s, absorbing rate remained above 83.4%, and the absorber shows a wide angle of incidence characteristics. By the analysis of RCS(Radar Cross Section), the absorber has a good RCS reduction feature, indicating that the absorber has potential applications in electromagnetic shielding, stealth, detection and other fields.

In this research a 3-DOF parallel mechanism with anti-torsion arm is designed as a ship-borne stabilization platform. For adapting to the serious sea conditions, such platform needs to couple the advantages of good mechanism stiffness, high bearing capacity and large workspace. Accordingly, a kinetics and kinematics based nonlinear optimization model is developed for the optimal design of parallel mechanism. The model is applied to synthetically optimize the workspace, stiffness requirement and kinematic performance of the 3-DOF parallel mechanism. An acceleration genetic algorithm is employed to seek the global optimization solutions of nonlinear optimization model. The solution results indicate that the designed ship-borne stabilization platform can not only provide a good performance, but also meet the design requirements.Copyright © 2015 by ASME

A novel wind direction monitoring system for the overhead transmission lines based on Fiber Bragg Grating (FBG) sensing is proposed in this paper. Compared to the existing systems, this system has several unique advantages, such as free from power supply on site, excellent ability to avoid electromagnetic interference, immunity to temperature and long lifespan. Firstly, with horizontal FBG arrangement, light intensity loss of the anemoscope is reduced and the monitoring distance is significantly enlarged. Then, optimization model is proposed to solve the contradiction between wavelength shift ranges of FBG and startup wind speed. Lastly, an algorithm is proposed to obtain wind direction and to eliminate the temperature effect. Experiments were conducted in a wind tunnel to calibrate the sensor. The results indicate that the startup wind speed of the anemoscope is 1.488m/s, and the anemoscope works properly under different wind direction.

This paper proposes a dynamic social network model for the competition among three languages with agent based social circles modeling method. The parameters of the topological structure of constructed social network are closer to parameters of the actual social network, and the parameters of social network can be adjusted by setting the different social radius of the individual agents. The individual agents on the network can move, dead and reproduce, so the constructed social network is endowed with dynamic characteristics. The model for the competition between two languages of agent nodes in the language competition network is extended to the competition among three languages model of agent nodes in the language competition network. Finally we constructed a complex agent network simulation model for the competition among three languages. The language types of the agents in the initial network represent only three kinds of language A, B, C, and three kinds of bilingual agents (AB, AC, BC) and a kind of trilingual agents (ABC) can be produced through learning and forgetting along with the network evolution, so the competitions among seven languages in the network come to be true. This paper analyzes the impact of the spread of the languages about the social status, the scope of social interaction (social radius) and the population mobility (mobile population proportion) in the competition among seven languages, and thoroughly analyzes the impacts of the language competition about the proportion of the population and the concentrated degree of population in the three languages community.

General difference filter can not only bring phase-shifting, but also induce the wave aberration. A new zero-phase algorithm is proposed. It utilizes cross power spectrum estimation to get the information about the signal's frequency value and phase shift and designs a phase corrector to complete the compensation of the filtered signal's phase and zero-phase filtering. This method has the advantages of easy implementation, high precision, good real-time performance, etc.. The results of MATLAB simulation show that the method has a reliable phase compensation performance.

A supercontinuum extending from 350 nm to more than 1700 nm is generated in microstructured fibre (MF) with randomly distributed air holes in cladding and core by using 15-fs pulses of a 790-nm laser. The maximum total power of the supercontinuum is 63 mW with 288 mW pump power from a 100× microscope objective. The wavelength and power of visible light ranging in the supercontinuum can be tuned by adjusting the input end of random the MF (to change pump incident point or incident angle). In particular, white light has been observed. The polarization states and waveguide modes of the visible light change with adjustment of the pump incident point or incident angle.

The grating groove density error (GGDE) will degrade the performance of the tiled-grating compressor, and the compensation for GGDE is of significance for improving the characteristics of the output pulses. With the ray-tracing method, analytical expressions considering GGDE are derived to predict the output beam drift and the output pulse broadening. According to the numerical results, we propose a compensation method to reduce the degradation of the tiled-grating compressor by applying angular tilt error and longitudinal piston error simultaneously. The tilt angle and the translation distance of the grating, as well as the allowable tolerance range of GGDE are obtained with this compensation method. By using the equiphase lines in the spatial-spectral interference patterns, the experimental results demonstrate that this compensation method can correct the angular drift of the output beams effectively, and compensate for the second-order and the third-order dispersion error well. Our investigation provides an efficient way to guide the adjustment of the tiled grating with GGDE.

The remarkable growth of 3D models on the Internet has posed a great challenge for model search. Many 3D search engines are based on tag matching, which is usually more accurate in identifying relevant models by alleviating the challenge arising from the semantic gap. However, the performance of tag matching is highly dependent on the availability and quality of 3D model tags. Recent studies have shown that tags that are specific to the visual content of 3D models are often noisy and unreliable in real-world environment, leading to a limited performance of autotagging. To address this challenge, we propose a 3D model autotagging method based on semi-supervised weighted metric learning. Extensive experiments show that the proposed method is significantly more effective than the state-of-the-art.

Satellite simulator is the simulation of a satellite. It constructs a realistic mission environment to test mission control system before the satellite is launched. And it can be used to train mission operators in the control center to improve their abilities of flight control. Fidelity of a simulator is very important. It can be greatly improved by directly embedding onboard software of the control subsystem into the simulator. At the same time, high-accuracy orbit dynamic simulating the complex space environment between the moon and the earth is also applied in a simulator to improve the fidelity of a simulator.

Automatic image annotation has emerged as an important research topic due to its potential application on both image understanding and web image search. Due to the inherent ambiguity of image-label mapping, the annotation task has become a challenge to systematically develop robust annotation models with better performance. In this paper, we present an image annotation framework based on Sparse Representation and Multi-Label Learning (SCMLL), which aims at taking full advantage of Image Sparse representation and multi-label learning mechanism to address the annotation problem. We first treat each image as a sparse linear combination of other images, and then consider the component images as the nearest neighbors of the target image based on a sparse representation computed by L-1minimization. Based on statistical information gained from the label sets of these neighbors, a multiple label learning algorithm based on a posteriori (MAP) principle is presented to determine the tags for the unlabeled image. The experiments over the well known data set demonstrate that the proposed method is beneficial in the image annotation task and outperforms most existing image annotation algorithms.

The analysis for lightning current facing in communication system has been analyzed and discussed in literatures. But the most of them are the situations of perpendicular to the ground for the lightning current, which is not universal. In this thesis, lightning current is simplified into a model of spatial diagonal current source, and ‘image method’ is adopted in the analysis of electromagnetic field distribution. The results show that lightning would create strong electromagnetic radiation when lightning occurs. This method provides a theoretical basis for further analysis of lightning protections.

Wireless Sensor Networks(WSN) is a hot spot of the research of wireless networks currently, the key of achieving efficient transmission business is to control node energy and improve the network lifetime i Chen You-rong n wireless sensor networks. The paper first uses Boolean sensing model based on Poisson point process to identify the function of the rate of coverage and the node density in unit area, and then calculates the total number of nodes in the region, next uses the greedy strategy of the Prim algorithm to find a spanning tree with the maximum weight, and constructs a approximate solution for the minimum connected dominating set. In order to control the commotions of the nodes, make the nodes in spanning tree to work, and other nodes are in sleep state. At last, further analyses the relationship between the number of nodes in connected dominating and the coverage radius.

To solve problems in aircraft large-scale thin-wall workpiece machining, this paper presents a multi-point location/support algorithm used in flexible tooling system. This algorithm reconstructs workpiece as high order NURBS surface with multiple patches in matrix form, distributes target points (points to be localized and supported) according to structure constriction, computes positions of location/support spheres in vacuum heads, and checks machine tool interference. Experimental results shows that this algorithm is able to achieve high accuracy, and ensure that machine tool do not interfere with location/support spheres in edge trimming.

The control of switched systems for regenerative retarding of electric vehicles is presented. On the basis of considering internal parameter perturbation and external disturbance, the vehicle regenerative retarding can be described as this switched system whose state matrix satisfies interval uncertainty and the nonlinear disturbance meets state secondary bounded. The robust switching control law is designed by using LMI method and convex combination technique. Simulation results show that the switching control of the vehicle regenerative retarding is robust and has the H∞ disturbance attenuation level γ. The control of current and voltage is stable and the braking distance meets the requirements of national standard.

A new method to measure the speed of rotating machines based on microcomputer and quadrature encoder is presented in this paper. The hardware and software of the measuring speed system are described. This circuit contains active crystal, quadrature decoder chips HCTL-2020 and LCD module. It can meet the requirement of the general speed measuring system. It can also display the speed situation on the LCD module. We can appropriately modify the program to make different displaying model on the LCD module. The speed measuring circuit also provides two interfaces of 9 pins and 15 pins, which is compatible with any other quadrature encoders.

An efficient and compact red laser at 458 nm is generated by intracavity frequency doubling of a continuous wave (CW) laser operation of a diode pumped Nd:LuVO4 laser at 916 nm under the condition of suppression the higher gain transition near 1064 nm. With 30 W diode pump power and a frequency doubling crystal LBO, as high as 9.6 W of CW output power at 458 nm is achieved, corresponding to an optical-to-optical conversion efficiency of 32.0% and the output power stability in 8 hours is better than 2.35%. To the best of our knowledge, this it the highest conversion efficiency of watt-level laser at 458 nm generated by intracavity frequency doubling of a diode pumped Nd:LuVO4 laser at 916 nm.

From the concept of Distance and Angle of matrix vector, we lead out the gray image similarity measurements: Distance Measurement and Correlation Measurement. Then the measurement algorithm is extended to color image matching field. The Distance and Correlation between two color pixels are defined and the color image similarity measurement is also defined accordingly. Finally we realize the color image matching, and have proved the robustness of the measurement method through simulation experiment.

In hatching process, temperature, relative humidity and oxygen concentration are three main parameters to the success of the incubator. Incubation system is a multi-variable multi-interference and time delay complex dynamic system, a hybrid intelligent control method is proposed. Based on characteristics of complexity and uncertainty for its mathematical models in the hatching process, this paper will divide the system into two structures, considering of the effect of throttle opening which causes temperature and relative humidity big interference and strong coupling, feed-forward compensation decoupling control algorithm is employed for before-class structure to realize the decoupling of main parameters. After decupling, according to different conditions fuzzy immune PID control algorithm or fuzzy control algorithm is selected for back-class structure to realize incubator intelligent control. Finally, the run of system verifies the effectiveness of the control algorithm.

For the polarization switching (PS) and the nonlinear dynamic behaviors (NDBs) of the optically injected laser system composed of master vertical-cavity surface-emitting laser (M-VCSEL) and slave vertical-cavity surface-emitting laser (S-VCSEL), we put forward a novel manipulation scheme and explore their control law by means of electro-optic (EO) modulation with quasi-phase matched technology in periodically poled LiNbO3. It is found that the PS of the S-VCSEL subjected to parallel or orthogonal optical injection undergoes a change of periodic oscillation with the applied transverse electric field. The envelope trajectory of the oscillation peak appears to be a cosine curve, and that of the oscillation wave trough becomes a sine curve. Besides, the PS of the S-VCSEL only depends on the applied transverse electric field and the bias current of the M-VCSEL, and is independent of the bias current of the S-VCSEL. When the bias current of the M-VCSEL takes a different value, the PS of the S-VCSEL shows a different evolution law in one period of the applied electric field. For a certain fixed bias current of the M-VCSEL, the optically injected S-VCSEL can emit an arbitrary polarization mode and its NDBs experience different evolutions when the light from the M-VCSEL goes through EO intensity modulation. If the output light of the M-VCSEL is subjected to EO intensity modulation and EO phase modulation simultaneously, while the bias current of the S-VCSEL is fixed at 1.06, that of the M-VCSEL is fixed at 1.18, and the optical injection strength is set at 5 ns-1, then the output polarization of the S-VCSEL is in turn switched from the y-LP to the left-handed elliptic polarization (EP), then the right-handed EP circular polarization, and lastly the left-handed EP. And its NDB shows in turn a single period, four doubled periods, chaos, four doubled periods, and chaos with the increase of the applied electric field.

One means of reducing the risk associated with the development of Anti-Lock Braking System (ABS) would be the ability to respond to the change of the tyre-road friction coefficient. In order to make accurate evaluation of the ABS performance, a possible solution is to research on bench testing technology. In this paper we put forward a simulation method of vehicle moment of inertia, in which the kinetic energy of the vehicle is replaced by the kinetic energy of the rotating flywheel, and the tyre-road friction coefficient is replaced by magnetic powder clutch. The amplitude of exciting current to the clutch has relationship with the friction coefficient, so as to provide a datum for testing the working status of ABS under various road conditions. The system can realise simulating test of single road surface, bisectional road surface and joint road surface. The validity of the road simulation method can be verified by the real-time data from the user interface.

Chemical mechanical polishing (CMP) is the most effective wafer global planarization technology. The CMP polishing head is one of the most important components, and zone back pressure control technology is used to design a new generation of polishing head. The quality of polishing not only depends on slurry, but also depends on the precise control of polishing pressures. During the CMP polishing process, the set pressure of each chamber is usually not the same and the presence of a flexible elastic diaphragm causes coupling effects. Because of the coupling effects, the identification of multi-chambers and pressure controls becomes complicated. To solve the coupling problem, this paper presents a new method of multi-chamber decoupled control, and then system identification and control parameter tuning are carried out based on the method. Finally, experiments of multi-chambers inflated at the same time are performed. The experimental results show that the presented decoupling control method is feasible and correct.

Defects in as-grown undoped and tellurium-doped gallium antimonide were studied using positron lifetime and coincidence Doppler broadening measurements. The grown-in defects in these samples were supposed to be Ga vacancy (VGa)-related defects. More VGa-related defects were introduced into undoped and lightly Te-doped GaSb after electron irradiation at the doses of 1.0 × 1017 cm−2 and 1.0 × 1018 cm−2; however, in the heavily Te-doped GaSb, electron irradiation led to partial recovery of VGa. The role of Te content in the defect evolution is also discussed.

It is crucial but challengeable that the generation of optical exact by synchronized seed pulses both for the main amplifier chain and for the pump-laser chain of an optical parametric chirped pulse amplification system, which are tried to be developed by the soliton mechanism. Detailed numerical simulation of the soliton propagation mechanism are accomplished. So the evolutions of solitons in time-domain and frequency-domain as well as the reciprocity characteristic with other nonlinear effects are clarified. Experiments are carried out, for validating the method of using soliton mechanism to generate ultra-broad band tunable ultra-short laser pulses. Forming, breaking up and self-frequency shift of a soliton are observed. The favorable tunablenesses of the wavelength between the visible and the near-infrared regions are exhibited. All these experimental results are well consistent with the theoretical analyses.

Anti-lock Braking System (ABS) has widespread use depending on its mature technology and superior performance. We design a test rig by an intensive study on the principle and testing techniques of ABS. It can simulate the running condition of wheels for ABS to test the braking performance. Measure and control system based on the CAN-BUS and the powerful LabVIEW software was adopted in this study for data acquisition and communication. The parameters of the test rig are set on the interface, and the data transmitted by the test rig is recorded and analysed simultaneously by applying it.

We demonstrate an efficient and compact yellow-green laser at 556 nm generated by intracavity frequency doubling of a continuous wave (CW) laser diode-pumped Nd:YAG laser at 1112 nm. An lithium triborate (LBO) crystal, cut for critical type I phase matching at room temperature, is used for second-harmonic generation (SHG) of the fundamental laser. With an incident pump power of 18 W, as high as 3.2 W of CW output power at 556 nm is achieved. The optical-to-optical conversion efficiency is as high as 17.8%, and the output power stability in 3 h is better than ±4.58%. To the best of our knowledge, this is the highest watt-level yellow-green laser generated by frequency doubling of a diode-pumped Nd:YAG laser at 1112 nm.