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In this article, molybdenum diselenide (MoSe2) was fabricated by chemical vapor deposition (CVD) with a modulation depth of about 7.3% and nonsaturable loss of about 30.6%. Bright-dark soliton pairs have been obtained in a thulium-holmium-doped fiber ring laser based on MoSe2 as a saturable absorber (SA) for the first time, to the best of our knowledge. The results not only prove that MoSe2 can be used as an excellent saturable absorber in the field of ultra-fast optics, but also provide a certain reference value for the future research on bright-dark soliton pairs based on two-dimensional materials.

The Internet of Things (IoT) is the Internet of everything connected. In the era of rapid development of the IoT, the paper summarizes the current progress of the IoT, and then finds out the high-dimensional tensor data generated by the IoT. However, with the increase of tensor data, the computing speed of the computer will decrease, and there will be corresponding privacy protection and compute problems. Therefore, this paper lists two applications that deal with different IoT scenarios, namely privacy protection, and heterogeneous computing. This paper holds that while processing data in parallel efficiently, protecting the security of data is the key point of the future development trend of the IoT.

Semantic segmentation, aiming to assign semantic labels to each pixel, is broadly applied into many fields, such as video surveillance, medical image analysis, and autonomous driving. However, there are two challenges in semantic segmentation task: 1) the deficiency of rich contextual information; and 2) the lack of sufficient spatial information, all of which affect segmentation performance seriously. To solve these two challenges, the global feature capturing module (GFCM) and Conv Block are proposed in this paper to build a new model to improve segmentation performance. Specifically, GFCM, made of the global encoding module (GEM) and spatial attention module (SAM), is designed to extract adequate global contextual information and build global spatial dependencies. Composed of three convolution layers, Conv Block is proposed to preserve rich spatial information. Based on GFCM and Conv Block, a new model is designed, where a data-dependent upsampling operator (DUpsampling) is exploited to recover the pixel-wise prediction effectively. The extensive experiments have been made to prove the effectiveness of the design, and the new model achieves 73.69% mIoU on Cityscapes test set and 80.05% mIoU on PASCAL VOC 2012 test set without any post-processing.

In order to improve the recommendation accuracy in collaborative filtering, this paper introduces deep learning into the recommendation algorithm, and proposes a personalized recommendation model and algorithm under the deep learning mode. Firstly, the advantages and disadvantages of common algorithms are analyzed; then, the deep learning mode is constructed, and the deep learning is integrated into the recommendation algorithm step by step; finally, the simulation data are verified by cosine similarity and probability based recommendation method, and the results show that the two methods get almost the same score, and get better recommendation results, which can effectively improve the recommendation progress and quality.

This paper analyzes the characteristics of hybrid multi-system, summarizes the requirements of multi-system intercore communication, and proposes a method and system for intercore real-time communication of hybrid multi-system. It is verified by experiments that the proposed method and system can meet the requirements. It can be applied to inter-core real-time communication of hybrid multi-systems in power systems.

In order to study the effect of wall insulation conditions and different airflows on burning rate of pool fires, a small-scale ethanol pool fire was conducted experimentally under three pool diameters and a certain lip height in a wind tunnel. The results showed that the non-monotonic mass loss rate decreases first and then increases with the increase of crosswinds at a certain lip height. The burning rate increases with the increased pool diameter of the non-insulated pool fires, while an opposite trend of burning rate was found in insulated pool fires at the same sizes. The dimensionless characteristics of Richard number presents the variation relationship between the buoyancy force and momentum during different airflows. The insulated liquid pool showed a higher burning rate than that in a non-insulated pool with the characteristic parameter of reciprocal of Richard number less than 2. With the value of Richard number continue increased, the burning rate in the insulated pool fires decreased due to the difference between the increased crosswind and heat transfer. The mass loss rate of pool fires without insulation increased with the increase of pool diameter, while an opposite trend was found in insulated pool fires at the same size. The experimental data supported to establish a ratio coefficient of burning rate with or without insulation under different crosswinds.

This Influence on the echoes of the chaff cloud by the translation and rotation of chaffs are studied according to the chaff spiral descent model. The characteristics of the frequency spectra and polarization of the chaff cloud are studied using the statistic method. Firstly, the spiral descent model of the chaff cloud is introduced, as well as the polarization scattering matrix of the rotation dipoles. Then, the self-correlation functions and cross-correlation functions of the elements of scattering matrix of the chaff cloud are analyzed, presenting the power spectra and cross power spectra of the elements of scattering matrix. Finally, the numerical results are given when the orientations of chaffs obey the uniform distribution and horizontal distribution.

The echo signals received by different antenna units are different in phases due to the difference of the wave paths, so phase comparison monopulse radars can produce phase differences accordingly, use phase detectors to detect the azimuth error signals and furthermore capture accurate azimuth and elevation angle information. Compared with conical scanning radars, monopulse radars boast high angular accuracy, fast speed and strong capacity for resisting angle deception jamming. Cross-polarization jamming can make use of the complex structure of the monopulse antenna pattern to generate angle deception jamming. This paper has firstly given the principle for angle measurement of phase comparison monopulse radars, designed the model of the cross-polarization pattern, established the model for angle measurement of the cross-polarization jamming and presented the reduction status of the angle measurement performance in the jamming environment by means of mathematical simulation. It can be seen that antenna pattern has different polarization structure. When the jamming intensity is enough, the cross-polarization jamming will reduce the accuracy of radar angle measurement by 40% which will degrade the tracking performance of radar.

Antenna polarization states always varied with scan direction, a new concept of spatial polarization characteristics of antenna is defined in this thesis. Phased-array behaves distinct property compared to mechanically-scanned antenna. The wave-guide slot phased array is used in this paper to study the polarization property with wide angle scan in airspace. Theoretical analysis and simulation proved that the lobe property and polarization changes not much in the case of small azimuth and elevation scanning angle. However, there is dramatic increase of cross polarization component in the main lobe with wide scanning angle. This characteristic can be applied to measure the target polarization scattering property in phased array radar searching stage. Based on the single polarized radar antenna, a novel polarization scattering matrix (PSM) measurement method is proposed by sufficiently utilizing the inherent polarization property of antenna which is not constant but a function of antenna's spatial scanning direction. Two orthogonal polarization channels are not required in this method. Just by using the prior knowledge of antenna polarization characteristics and improving the signal processing mode of received radar signal, the PSM of target can be obtained.

By combining with the latest theoretical results of distribution voltage control for distribution network, a voltage control simulation system based on. NET platform of distribution network containing a large number of photovoltaic power sources is designed and developed, which provides supplementary analysis for planning decision-making of voltage control. The system is developed in Microsoft Visual Studio 2010 platform integrated with the GIS plug-in component MapX. In the end, a modified IEEE33-69case is used to validate the feasibility of the proposed simulation system.

The coherent jamming strategy against LFM radar is one of the hottest research topics. This paper proposes a radar target echo cancellation method based on periodic sequence phase-modulation. Firstly, the mathematic principle of periodic sequence phase-modulation is analyzed and the matched filter result of the jamming signal is presented. Then the conditions for cancellation, including the time delay, jamming phase and jamming amplitude, are discussed in detail. Finally, the cancellation result of target echo is verified by simulations. The simulation results prove the correctness and effectiveness of the proposed method. This work is an effective multiple false targets jamming method with the ability to cancel the target echo. It is beneficial to the design of the jamming signal.

The large-scale transmission network expansion planning requires high computational speed and accuracy, so combining the DE (differential evolution) algorithm with the EDA (estimation of distribution algorithm), whose algorithm probability update mechanism is improved according to the characteristics of the transmission network expansion problem, a EDA/DE hybrid algorithm is presented to solve large-scale transmission network expansion planning problem. At the same time, taking into account the grid company investments, incentive policy for renewable energy as well as the security constraints, based on the embedded cost, wind curtailment and risk value, a multi-objective static planning model for transmission network expansion and wind power network optimization is established. IEEE24 RTS node example demonstrates the validity and applicability of the proposed algorithm.

In order to accomplish the fault prediction of complicated and enormous mechanical equipment, this paper proposed a fault prediction model for complicated mechanical equipment that based on rough sets theory and BP neural network . Firstly,the discretization of continuous data was implemented by the discretization algorithm based on dynamic hierarchical clustering in rough set theory;secondly, an improved algorithm based on discernibility function attribute reduction was used to reduce the decision table to remove redundant attributes of decision table,then the reduced data were input into BP neural network for fault prediction. Finally, case studies are conducted to predict the failure of cutterhead of shield machine.The experimental results showed that the prediction model can effectively reduced the input information, simplified the neural network architecture, shortened the training time and improved the efficiency and accuracy of fault prediction.

GPS or other types of navigation devices are usually used to complete the INS correction, but these methods need to increase the hardware equipment. This paper designs a new inertial error estimation method based on sequential square root filter, the passive radar seeker has to obtaining sight angle measurement information of unknown punctuation to correct the inertial navigation scheme, after fusion filtering INS position and attitude navigation error is corrected. The results show that the observation value of the traditional navigation equipment also has the potential to correct the inertial navigation system, and the hardware in the loop simulation platform is established.

A real-time bi-directional LED-to-LED VLC system is developed. The test results show that the proposed system can realize a downlink and uplink speed at 2.6Mbps and 2.55Mbps over a transmission range up to 2m.

Cluster head selection has always been the key to enhance the whole network performance. However, it is hard to decide which node should be selected. In addition, in some cases there would be multiple choices for a cluster head selection. As a solution to the problem above mentioned, a Cluster head selection Optimization with electrical Voting (COV) is proposed in this paper. COV would provide the optimal result of cluster head in a node-group, and COV could give multiple results for the cases with multiple optimized solutions. In addition, COV could further calculate the global solution if further information for solution compression is provided. Evaluations show that COV is capable for cluster head optimization.

In order to analyze the electromagnetic compatibility of communication system, a test method based on symbol error rate (SER) is proposed, then the experimental system was built. The influence of in-band electromagnetic interference on communication system was studied, and the mechanism was got. The results indicate that for the same frequency interference, the SER increase slowly in the front 2 dBm range, the later 1 dBm, the SER increases rapidly until the SER gets 0.47, then the SER remain unchanged, the interference power is always proportionate to the transmit power. The quality of message is damaged when the SER gets 10−2 level, and the display screen crashes when the SER is 0.47. In the transmit frequency 2 MHz range, the communication system is easy to be disturbed.

The study of how an aircraft's inter satellite antenna tracks a relay satellite is an important and foundational problem. This paper researches the tracking law from the view of an engineering application. Firstly making a reasonable and simplified model of inter satellite antenna's pointing mechanism, which is placed on a aircraft, in accordance to the structural characteristics and movement constraint of the pointing mechanism. In which, the kinematics of the pointing mechanism may be studied. Secondly establishing the model's kinematic model through geometric methodology. This kinematic model can calculate the needed angular displacements of the pointing mechanism placed on the aircraft when tracking the relay satellite whose coordinates are known. Furthermore, an analytical interface on the basis of the kinematic model was established. Through the interface, the demanded solutions of the inter satellite antenna's pointing mechanism are conveniently and quickly obtained. Finally, the degree of error regarding the analytical interface of the kinematics model was analyzed. The results show that the built kinematic model is able to meet the requirements of engineering.

In order to improve the fidelity and controllable of electromagnetic environment(EME) building, and build realistic EME for testing and researching the complex EME effect on the electronic information systems, this paper puts forward Equivalent building methods of complex EME based on the meta-elements. First, the paper analysis the domestic and foreign research which presents the current situation and the demand, and then puts forward the methods and expounds the core idea of basing the meta-elements to realize the equivalent EME building. Further it introduces extraction method of the electromagnetic signal environment meta-elements, and builds the description of them. In the end, it put forward the method and process to build the complex EME based on the meta-elements. This research results provide the technical support to improve the level of test EME building.

This paper describes an iterative, efficient, and use-case driven UML object modeling method used in the process of software development of an ocean parameters measurement system. The method solved all kinds of complex issues (complex related factor), variety (variety of equipment and data types), and frequent changes in the software development of an ocean parameters measurement system.

This study estimates the underwater structure acoustic radiation areas, mainly in the following aspects: analytical methods, boundary element and finite element, etc. This approach is a significant for mastery and understanding of the underwater structure vibration and radiation mechanism, calculations, theoretical estimates and acoustic design. From the engineering point of view, these algorithms are faced with a huge amount of numerical calculation, a long calculation time, and frequency band is limited and other issues. A method is brought forward to estimate acoustic radiation based on vibration data from underwater structures. On the assumption that there is some transfer function relationship between underwater structure radiated noise and vibration monitoring data, the relation is multi-input, single-output and convergent, and the method of exponentially-weighted is adopted. Firstly, according to the thin shell equation and wave equation, we establish a large-scale cylindrical shell vibration/radiation model; simulate resonance relation of vibration monitoring data and acoustic radiation; and verify the method of data weighting. Then, we explain that the estimation error of acoustic radiation decreases when the number of monitoring points and the sample size increase; and, that the error will remain within a range of 3dB when the increase reaches a certain level. Finally, through the verification of ship measurement vibration monitoring and acoustic radiation data, the estimated value and the true value have a good consistency. This method has a small calculating burden and a fast speed, and it is also both reasonable and feasible. It is possible to apply the method to an engineering estimation.

For upper limbs disabled patients, in order to improve the effects of rehabilitation training, and enhance therapeutic safety, a kind of 3-DOF pneumatic artificial muscle (PAM) bionic elbow joint was designed, and the inverse kinematic mathematical model was built by the pseudo-rigid-body model. Then, the simulation and analysis were done for inverse kinematic problems, based on the model. Finally, the experimental measurement system of the PAM bionic elbow joint was established, and then the motion control was done via a PID controller. The results show that PAM movements are continuous and stable in the designed workspace. This means the mechanism has good smoothness during movement. Furthermore, the actual and expected rotation angle curves of the forearm disc are basic overlap by adjusting PID parameters, so the inverse kinematic model is accurate.

Electromagnetic environment prediction refers to forecast the developing trend of electromagnetic environment in future based on forecast model. Through the research on the constitute and the dynamic characteristics of electromagnetic environment, according to electromagnetic environment simulation process and external interference electromagnetic environment, mutual interference, dynamic characteristics of the electromagnetic environment faced by electronic information equipment, external interference model, the internal mutual interference model and the dynamic control model of electromagnetic environment are established. At last, according to the electromagnetic environment simulation and prediction, multi point receiving simulation method are put forward and the simulation process is established, which provide support for electromagnetic environment prediction research. Comparison of simulation and outdoor experiments show that the prediction models and methods described herein improve the efficiency and accuracy of prediction of the electromagnetic environment.

Radio Environment Map (REM) is a map that indicates the radio signal strength (RSS) over a finite geographical region. It enables cognitive radio (CR) users to opportunistically access to the spectrum unoccupied by the primary users (PUs) who are licensed to use specific spectrum. In this paper, a basis expansion based scheme is presented to estimate REM. We take the sparsity of preselected basis functions and the inherent time-varying spectrum usage of primary users into account such that the RSS estimation is formulated as a recursive least squares (RLS) problem with an l1 norm constraint. A distributed algorithm is presented to solve the RLS problem. Each SU only need to exchange information with its one-hop neighbours to sketch the REM with radio signal strength. Finally, simulation studies are presented to validate the performance of the proposed method.

Urine test strips are frequently used to analyze health status of patients due to its simplicity. However, in order to analyze the urine test strip, expensive hardware is required to match changed colors. In order to solve the problem, a novel design of the urine test strip is proposed. By using the proposed design, extra equipment is not required and the proposed design is robust against illumination changes. Through a series of experiments, the proposed design gives a correct decision in general, dim, and flash light condition.

This paper focuses on the problem of secure distributed consensus to defend covert misbehavior in wireless sensor networks (WSNs). Distributed consensus is a promising method to improve the efficiency and precision of consensus results in WSNs, but it introduces new security issues that malicious nodes may manipulate false sensing data to degrade the sensing result of the whole network. A data falsification attack, i.e., the attacker injects random values into its neighboring nodes at each time-step of consensus process, is considered. This kind of attack cannot be defended against by most of existing detection mechanisms. We present a distributed detection mechanism with adaptive local threshold to isolate the abnormal nodes. A Weighted Averaging-based Consensus Scheme (WACS) is proposed to decrease the negative impact of the attack and make the network converge to a consensus value. It is proved that convergence property can be guaranteed by the relationship between weighted average of the noise and stochastic approximation. Simulation results are presented to show the effectiveness of the proposed secure scheme.

The cost performance of radio simulation software is not high because of radio's characteristics of variety frequent update and complete function. An idea of radio simulation training platform design based on components is put forward through analyzing of the various components and functions of the radio. The article design functions and technical architectures of the simulation platform. Component implementation methods are discussed. The platform is primarily developed in work. That proves the idea's feasibility.

Based on array signal processing, the method that smart antennas beamforming by general neural network in wireless communication is proposed, which improves the accuracy of algorithms, such as MVDR algorithms, DOA algorithms etc. 10-elements uniform line array is simulated by computer, Simulation results have shown that we can obtain the extremely approximate weight vector by using the neutral network method. The method is much better than MVDR in computing speed. The proposed method is effective. Computer simulation experimental results are in line with the theoretical ones.

Based on in-situ monthly sand-dust days data atmeteorological stations and MOD10A2 data, which are 8-day composite snow cover observation at 500m spatial resolutionduring November and next March from 2000 to 2008. The spatial and temporal distributionof sand-dust weather and snow cover during late fall and early spring in Gansu and Inner Mongolia were investigated via monitoring sand-dust days and snow cover fraction. The correlations between sand-dust weather and snow coverwere analyzed. The result shows that there weretwo centersof sand-dust in the study area, i.e., the western XilinGol League in Inner Mongolia and the west of Alxaleague in Inner Mongolia to the north of Yellow river in Gansu. Whilethe most extensive and persistent snow cover was located in high latitude and elevation, where sand-dust rarely appeared. During late fall and early spring, the days of sand-dust with different intensity had seasonal variations withslight fluctuation at the beginning and then increased rapidly. The snow cover fraction is just the reverse, it increasedat first and then decreased. On the annual level, the sand-dust represented a significant reduction, andthe snow cover fraction exhibited a weak rising trend. Therefore, to some extent, the correlation between snow cover fraction and sand-dust days is negative. It indicates that snow cover has some restraining effects to sanddust weather, andthe inhibiting ability is closely related to the intensity of sand-dust, the amount of the snowfall, and the distribution of sand source.

Beach wetland, an important part of the river ecosystem, plays an insignificant role on the stability of the river ecosystem as a transition zone between the river and terrestrial ecosystems. Since the operation of Three Gorges Reservoir, water discharge, river channel erosion and lowering, the collapse of river bank slope at downstream of the dam and shrinkage of the beach, result in the adverse impact on the waterway conditions and also reduction of beach area in the middle reaches of the Yangtze River. In response to adverse changes in the middle reaches of Yangtze River since the operation of Three Gorges reservoir, Yangtze River Waterway Bureau will implement numerous protection engineering to prevent the collapse of bank and the degeneration of the beach. In the recent years, the protection structure with ecological functions is more and more widely used. The test proved that the colonization of plants in the structure of ecological protection can restore the beach vegetation, species diversity, and to prevent the wetland area to reduce and improve the ecological environment of the local area.

Landscape pattern analysis is the basis of landscape ecological assessment, programming, management and construction. From three aspects, this article analyzes the landscape pattern change of Yarkant irrigated area in recent 20 years and forecast the future tendency. Firstly, the LUCC (Land-Use and Land-Cover Change) is obtained from TM images. Secondly, the landscape pattern change is indicated from Fragstats 3.3 software. Finally, using Markov forecast model the trend of LUCC in 5 years is predicted. The results show: 1) the construction land and cultivated land increase remarkably with the reinforcement of irrigation works; 2) the patches' degree of fragmentation becomes higher and all types have uniform distribution.

Stereo vision has long been studied and a great variety of algorithms have been proposed to estimate the disparities from the stereo image pairs. However, when stereo matching algorithms are applied to real world images, especially out door image sequences under sunlight, they can hardly produce desirable disparity maps as they perform on standard stereo image pairs. Consequently, we proposed a method based on histogram equalization and tophat filter to mitigate the influence brought by illumination. Then, belief propagation is used in our method to generate the disparity map. In order to evaluate the effectivity of the proposed methods, some experiments are executed with two outdoor stereo sequences and the results indicate that disparity maps after preprocessing through our method perform much better than directly using stereo matching algorithms.

Objective: To investigate the feasibility of delineating individual gross target volume (GTV) for tumors moving with respiration by using AIP/MIP CT instead of 4D-CT. Methods: CT data of three patients were acquired in Cine mode. The Cine duration time for each couch position is 4~6s, which equals to one breathing cycle plus 1s. The acquired CT data were input to a 4D-CT reconstruction system made in house to reconstruct AIP/MIP and 4D-CT. Then, the characteristics of motion tumor in AIP/MIP and 4D-CT were analyzed. The influences of window width/level on the appearance of periodical motion target in AIP/MIP CT were investigated by using a periodical motion phantom. Results: The GTV in AIP (GTVAIP) and MIP CT (GTVMIP) was bigger than that in extra-inhale phase 4D-CT (GTV4D-in) or extra-exhale phase 4D-CT (GTV4D-ex). The ratios of GTVAIP to GTV4D-in for two patients were 1.30 and 1.07, and the ratios of GTVMIP to GTV4D-ex were 1.57 and 1.21, respectively. AIP/MIP CT with appropriate window width/level can be used to derive the individual target motion envelope. Conclusions: AIP/MIP CT could be used to quickly delineate individual GTV for moving tumor, which may significantly reduce the target delineation laboring. It can be used to replace 4D-CT to derive the individual GTVs for tumors moving with respiratory.

In wireless video communication, error concealment is a key question because of high error bit. This paper focus simulation error concealment based on the error hiding technologies based on content, and analyze the performance of various technologies, and finally given in the actual communication system to choose a suitable error concealment technology.

This paper employed an index called surface temperature change (STC) for assisting the sandstorm forecasting over Northwest China. The index was retrieved from Chinese FY-2D/S-VISSR (Stretched - Visible and Infrared Spin-Scan Radiometer) data. For examining the accuracy of sandstorm forecasts that regard STC as a predictor or not, we applied this index to all sandstorm cases that occurred in research region during 2007–2008. The results showed: 1) Employing the STC as a single predictor, 2/7 of those cases were successful predicted; 2) Comparing the sandstorm forecasts which just considered conventional meteorological data with those considered both conventional data and FY-2D retrieved STC, the latter forecasted 1/6 of cases those the former failed to forecast. It indicated that satellite retrieved STC has a little value as a predictor for sandstorm forecasting over northwest China, but only serves as a complement to the ground observations of temperature variations. Because of the ultra high temporal resolution of this index, it would have a better performance in dynamic analysis/rolling forecast cases.

Underlying surface data used in a sand and dust model is critical to its output results. In this paper, investigation of effects of the used underlying data on its outputs was carried out by using GRAPES_SDM to simulate a severe dust storm process occurred from 23 to 25 April, 2010 in Minqin, China with latest and original underlying data for sensitive and control test, respectively. The results show that changes of land cover results in changes of model outputs in extent and intensity of surface dust emission and dust concentration and its spatial distribution. However, the effects on dust concentration are primeval and ambulant. It also displays that the stimulation top dust concentration value obtained by the updated data is 5200 µg/m3, which corresponds better to the observations (6000 µg/m3) than that of the original one (7700 µg/m3), indicating higher precision.

In this paper, using 16 days 250m MODIS vegetation index dataset, the relationship between eight vegetation indexes (VIs) and aboveground biomass in Gannan grassland of China, was analyzed. Based on their correlations, monitoring models of aboveground biomass was constructed, and then the aboveground biomass of the whole Gannan Autonomous Region and its every county were estimated. The results showed that in most growth period, there are very significant relativity between vegetation indexes and aboveground biomass, which is the most obvious with synchronous EVI(r=0.782). And the cubic polynomial model of EVI fits aboveground biomass better than other vegetation indexes and functions. Based on above formula, aboveground biomass of Gannan grassland in 2007 and 2008 are seperately 5610kg/hm2 and 5605kg/hm2. As to every county, comparing with that in 2007, aboveground biomass of 2008 in Lintan, Zhuoni and Diebu County increased, while in Hezuo, Maqu, Luqu, Xiahe and Zhouqu County it decreased.