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Recently, the optical remote-sensing image-captioning task has gradually become a research hotspot because of its application prospects in the military and civil fields. Many different methods along with data sets have been proposed. Among them, the models following the encoder–decoder framework have better performance in many aspects like generating more accurate and flexible sentences. However, almost all these methods are of a single fixed receptive field and could not put enough attention on grabbing the multiscale information, which leads to incomplete image representation. In this letter, we deal with the multiscale problem and propose two multiscale methods named multiscale attention (MSA) method and multifeat attention (MFA) method, to obtain better representations for the captioning task in the remote-sensing field. The MSA method extracts features from different layers and uses the multihead attention mechanism to obtain the context feature, respectively. The MFA method combines the target-level features and the scene-level features by using the target-detection task as the auxiliary task to enrich the context feature. The experimental results demonstrate that both of them perform better with regard to the metrics like BLEU, METEOR, ROUGE_L, and CIDEr than the benchmark method.

Smart contracts increasingly cause attention for its ability to widen blockchain's application scope. However, the security of contracts is vital to its wide deployment. In this article, we propose a multilevel smart contract modeling solution to analyze the security of contract. We improve the program logic rules for bytecode and apply the Hoare condition to create a Colored Petri Net (CPN) model. The model detection method provided by the CPN tools can show the full-state space and the wrong execution path, which help us analyze the security of the contract from several perspectives. The example shows that the counter-example path given by the contract model is accord with our expected results based on code analysis, proving the correctness of the solution. In addition, we design a highly automated modeling method, introducing custom call libraries and a path derivation algorithm based on backtracking, which improves the efficiency and pertinence of the dynamic simulation of CPN models.

Some non-digitized measuring instruments such as pointer meters are utilized by some farmlands by virtue of their high stability and accuracy, and the data collection depending on the human movements requires considerable time and effort and has a low technology level. Therefore, an intelligent pointer meter indication reading and automatic collection method is proposed using machine vision and wireless sensor network (WSN) technology. An intelligent pointer meter indication reading device consisting of an image acquisition module, an intelligent control center, a wireless transmission module, and a power module was developed, which could accomplish intelligent meter indication reading and automatic data uploading. Furthermore, a pointer meter indication reading algorithm for a resource-limited environment is proposed. Firstly, the pointer and the circle axis were recognized by using edge detection and the geometrical characteristics of the pointer meter, and then, the scales and scale values were determined using the statistical characteristics of the circles around the pointer’s vertex. Next, by utilizing the density-based spatial clustering of applications with noise (DBSCAN) algorithm, we adjusted the scales and the scale values, taking full advantage of the pointer’s characteristic that the scales’ rotation angles changed linearly with the scale values, which were classified by an SVM taking in the HOG feature as the input. Finally, the indication was computed in terms of the relative position of the pointer between the adjacent scale values, and the accuracy was 94.2%. The proposed method was evaluated by comparing it with some newly published algorithms. The pointer detection method had stronger robustness and anti-interference capability than the image segmentation method and the skeleton extraction method. The Θ(n) value, indicating the complexity of the scale detection algorithm, was considerably smaller than the Θ(n2) value, denoting the modified central mapping method used mostly for scale detection. The energy consumption by each module was measured, and the results showed that the image acquisition module accounted for the largest energy consumption, 87.7%, which was more than eight times as much as the second-largest energy consumption, 10.3% (that of the wireless transmission module); the problem of power supply could be solved by using solar panels.

Wind turbine blades play a key role in the wind energy collection system. Deformation measurement for turbine blades is an important and efficient way to prevent blade damages. Here, a novel and low-cost measurement method of static deformation for wind turbine blades using home-made LiDAR was proposed, and then verified by measuring the flap-wise load bending of a wind turbine blade model. The horizontal and vertical angular resolution of the proposed system are 0.09° and 0.225°, meaning a high resolution of 500 × 200 distance points in a 45° × 45° field of view of each depth image. The visualization and processing of depth images was realized using Point Cloud Library. To fast segment the 3D wind turbine blade model from background data, we also proposed a segmentation approach based on Euclidean clustering and union-find algorithm. The experimental results show that this method can segment the blade model from acquired data effectively, reducing the time-cost by nearly 50%. Furthermore, the bending degrees and curvatures of the blade in different buckling loads can be calculated using processed data. The proposed method can realize low-cost, on-site, portable and visualized deformation measurement for wind turbine blades and would be a promising way to test blades and prevent blade damages.

We report room-temperature near-infrared nanolasers based on AlGaAs/GaAs nanowire/single-quantum-well heterostructure grown by MOCVD. When subjects to pulsed optical excitation at room temperature, the nanowire exhibits lasing at 791 nm with low threshold of 2.5 kW/cm2.

Spontaneous emission of luminescent material is strongly dependent on the surrounding electromagnetic environment. To enhance the emission rate of a single-photon emitter, we proposed a wire-groove resonant nanocavity around the single-photon emitter. An InGaAs quantum dot embedded in a GaAs nanowire was employed as a site-control single-photon emitter. The nanoscale cavity built by a wire-groove perpendicular to the quantum dot with an extremely narrow width of 10 nm exhibited an extremely small volume of 10 &times, 40 &times, 259 nm3. Theoretical analysis showed that the emission rate of the quantum dot was dramatically enhanced by 617x due to the Purcell effect induced by the wire-groove cavity. A fast single-photon emitter with a rate of 50.2 GHz can be obtained that speeds up the data rate of the single-photon emitter. This ultrafast single-photon source would be of great significance in quantum information systems and networks.

With rapid development and wide application of the mobile intelligent terminal equipments, increasingly huge storage space is required. Therefore, it is particularly important to design a storage system based on the current mainstream operating system Android. In this paper, a high-quality speech storage system based on MELP speech coding algorithm is designed and implemented on Android system. The speech rate can be compressed to less than 0.5% with high speech quality level to provide more efficient speech transmission and storage for mobile intelligent terminals.

In order to solve the problems of traditional paper-based technology data storages difficulty and maintenances low efficiency, adapt to the modern information development needs, in the system studied the design of Interactive Electronic Technical Manual (IETM) based on S1000D specification, given the overall architecture model of IETM authoring platform. Firstly introduces S1000D specification, mainly introduces the two core contents that Common Source Data Base (CSDB) and Data Module (DM) of creation IETM based on S1000D, studies the design and implementation of DM. Describes the application of Extensible Markup Language (XML) and relational database in the IETM creation, established the mapping relationship of XML and relational database conforms to the S1000D specification, and gives the method of conversion between XML document and relational database. In order to enhance the easy operation of human-computer interaction, studies the application of speech recognition in the creation of IETM platform and system introduces the process of IETM creation.

Standard is the precondition of IETM, and the data format is the core of IETM, standardized IETM data format will regulate the IETM technology information, and improve the use efficiency and the management of IETM. Many countries have established their own series of IETM technology standard, which is the standardized management for development of IETM. Our country also established the IETM standard suitable for our army--GJB6600. This paper has carried the international standard data format of IETM on the contrast analysis, and researched on the data model regulated by the GJB6600 IETM data format standard. It also analyses the data module structure, the data module coding structure and the data module logic structure of GJB6600 data format, and to conclude the advantages of this kind of data model. This paper has great help for the development of our country and the IETM technology of our army.

This study presents an interval bus departure frequency programming model for traffic system pollution control through odd-even restrictions on private vehicles policy under uncertainties. The restriction policy results in enormous cost of the public transportation system especially in peak hours. The developed model can effectively quantify the relationship among system cost, execution time of the restriction policy and traffic environment by considering the uncertainties of traffic system. The uncertainties presented as interval numbers in the public transportation system can be quantified with the interval programming. The developed model is applied to Wuhan city, China. The results indicate that the efficiency of the program is significantly influenced by automobile ownership, the execution time of the policy and the level of emission. Besides, the program can easily be extended to all bus routes for vehicle emissions management.

Research of anti-laser-eavesdropping devices is very critical to the security of confidential meetings for the nation and enterprises. Based on the depth study of laser eavesdropping principle as well as the human hearing characteristics, an implementation of anti-laser-eavesdropping was proposed. The system is composed of the noise generators and vibration transducers. Voice signals before and after eavesdropping were compared, the results of which show that the anti-laser-eavesdropping devices could produce noise signal which could mask the voice signal and successfully block the laser eavesdropping channels.

RBC(Radio Block Center) handover of high-speed train impacts greatly on the safety and efficiency of train operation. This paper proposes and studies a new RBC handover model considering the status quo of dominant movement authority sent to the RBC-crossing train by two neighbor RBCs The basic data, in which the movement authority is hidden, is send by one or two of neighbor RBCs to train. The automatic train control will be realized by the clarity of the hidden movement authority. The simulation shows that the new model can improve the efficiency of traffic organization significantly, and further enhance the safety of train operation.

In order to search after a new way for the propulsion system of the tracked vehicle, a novel type of power-split hybrid propulsion system is proposed. Its configuration and working mode are set down, and then its power distribution and control strategy are also analyzed. A collaborative simulation model is built to simulate the system, based on interface technology between AMESim Software and MATLAB/Simulink Software. The mechanical assembly is modeled by AMESim; meanwhile the control system model is built by MATLAB/Simulink. Finally, the simulation result shows that the performances of the new hybrid propulsion system are superior in many respects to the comprehensive hydraulic-mechanical gearbox and especially its acceleration time is only 7.9s from 0 to 32 km/h.

Objective To evaluate the efficacy and safety of implantable cardioverter defibrillator (ICD) and cardiac resynchronisation therapy-defibrillators (CRT-D) avoiding defibrillation threshold (DFT) testing when treating ventricular tachycardia (VT) or ventricular fibrillation (VF). Methods We analysed a continuous database of the 21 patients who had avoided DFT during ICD implantation from Oct. 1999 to Aug. 2008. Follow-up data were completed and analysed in the 21 patients with ICD implantation. Results ICDs were implanted successfully in 17 patients with VT or VF, and CRT-D were implanted successfully in 4 myocardiopathy patients with severe heart failure who avoided DFT during ICD or CRT-D implantation. Eight patients accepted DFT 1 week later, VT orVF was not induced in 3 patients (37.5 %). During the mean follow-up of 1–7 (4.2±1.9) yrs, malignant ventricular arrythmia was recorded in 16 patients. Among them, 89 episodes were successfully terminated by defbrillation (100%), 120 VT events were terminated by the first run of antitachycardia pacing (51.1%) and 22 by low engery cardioversion (59.2%). All patients took antiarrhycardia drugs after ICD or CRT-D implantation. No patient died from malignant ventricular arrythmia during the follow-up. Conclusion No application of routine DFT may aviod complications associated with DFT during ICD or CRT-D implantation. ICD or CRT-D implantation may effectively treat fatal ventricular tachyarrhythmias and prevent sudden cardiac death.

Pyrite has a significant effect on the spontaneous combustion of coal. The presence of pyrite can change the propensity of coal towards spontaneous combustion. The influences of various pyrite contents on the parameters of spontaneous combustion, such as index gases, temperature and released heat etc., were investigated in this study. Coal samples with different pyrite contents (0 %, 3 %, 5 %, 7 % and 9 %) were made by mixing coal and pyrite. The oxidation experiments under temperature-programmed condition were carried out to test the release rate of gaseous oxidation products at different temperatures. Differential scanning calorimeter (DSC) was employed to measure the intensity of heat release during coal oxidation for various pyrite contents. The results indicate that pyrite can nonlinearly accelerate the process of spontaneous combustion. The coal sample with a pyrite content of 5 % has the largest CO release rate and oxygen adsorption as well. However, the coal sample with a pyrite content of 7 % has the largest rate of heat flow according to the results from the DSC tests. Pyrite contents of 5 %–7 % in coal has the most significant effects on spontaneous combustion within the range of this study. The conclusions are conducive to the evaluation and control for the spontaneous combustion of coal.