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Long-distance wireless energy transmission is realized by photoelectric conversion through lasers and photovoltaic cells. However, existing devices have low transmission power and low transmission efficiency. Exploring the main factors that limit the transmission efficiency during transmission is necessary to improve the transmission power and efficiency, and theoretically analyze these factors that affect transmission efficiency, such as beam quality, divergence angle, wavelength and so on. This will provide research directions for subsequent work. A multiwavelength laser wireless energy transmission experimental platform was built by using powersphere, laser with three different wavelengths and other devices. This platform was used for transmission efficiency verification experiment. The total electro-optical-electric conversion efficiency values obtained by the 532, 1030, and 808 nm lasers are 0.01%, 0.08%, and 0.11%, respectively. The corresponding laser-to-electric conversion efficiency values are 1.37%, 1.60%, and 0.73%, respectively. Experimental results show that the electro-optic conversion efficiency of the laser and the photoelectric conversion efficiency of the photovoltaic receiver is the main reasons for the low conversion efficiency of the system. In addition, factors such as the expansion ratio of the beam expander, laser collimation, laser uniformity at the photovoltaic receiver end, and circuit structure, affect the conversion efficiency of the system.

The model of rotor vector (RV) reducer was established by 3D software, and was imported into ANSYS Workbench for transient dynamic analysis. The stress distribution diagram and total deformation diagram of the gear tooth surface during the meshing process of the cycloidal wheel and the pin wheel were obtained, and the stress distribution law of the cycloidal wheel in the process was also obtained. Comparing the calculation results of Hertz formula with the results of finite-element analysis showed that the deviation are smaller and within the allowable range, which provides the theoretical reference for the optimisation of the cycloidal wheel.

Overlay marks contrast plays such a fundamental role for the overlay metrology that it dominants the accuracy control and draws much attention during mark evaluations. However, as the lithography nodes advances and the 3D device stacks accumulate, overlay marks sub-segmentation and opaque hard-masks are widely exploit, both of which can be drawbacks for mark contrast in certain cases. As a result, the overlay mark contrast improvement techniques become a necessity, and attract more research interests. In this paper, we introduced a method to improve the mark contrast by using pixel improvement technique and theoretical reference correlation analysis. Such method can potentially be very effective when measuring overlay marks with extreme low contrast through thick opaque layers.

The powersphere is a device used for maximizing the conversion of light in wireless energy transmission via laser. It is a spherical structure made up of thousands of photovoltaic cells. Due to the large dimensions and existence of many holes in the spherical surface, there are some drawbacks in machining, such as limited movement space of the machines, long cycle, low precision, and high cost. In this context, with a powersphere irradiated by the laser as the model, the principle of powersphere is deduced theoretically. It is proven that the illuminance value at any position on the inner wall of the powersphere is equal, and the calculation formula of this value is derived. Based on this theory and the comparative analysis of processing methods and the results of processing experiments, the structure of the powersphere is designed. The experimental processing of the powersphere is carried out by selecting the welding method. Finally, two hemispherical powersphere frames are processed, which are connected by screws to form a ball frame for the installation of photovoltaic cells. The results show that the improved design and fabricating method can process the powersphere quickly, accurately, and economically. A comparative experiment of powersphere and photovoltaic panel was carried out. The experimental results show that the powersphere has the function of light uniformity and repeated use of laser. So, the designed and processed powersphere is consistent with the theoretical analysis.

As the light of the belt conveyor changes drastically and unevenly, it will cause the longitudinal tear detection rate of the traditional methods drop sharply. To improve the situation, a novel method, which replaces the traditional geometric features with the Haar features, is proposed. First, the Haar feature was employed to train weak classifiers. Then, the AdaBoost algorithm is utilized to upgrade the weak classifiers to strong classifiers. Finally, the Cascade algorithm is introduced to combine strong classifiers in series into a cascade classifier that can reduce the training and processing time. The experiment following the above proposed method has shown that the recall, accuracy, and precision of tear detection under uneven light almost approaches the level under the uniform light (less than 3% difference), which indicates that our method is more accurate and robust than the existing methods in real-time belt tear detection.

Sea cucumber, Apostichopus japonicus, is the main cultured species in China. The main culture style for this species is the sea ranching model. Field trials were conducted in bottom-cages to preliminary reveal optimal releasing size, as well as maximum density of A. japonicus in an integrated multi-trophic aquaculture sea ranching area. Different sizes (4–30 g ind−1) and densities (336–1342 g m−2) of sea cucumbers were cultured for 13 months in Rongcheng Bay, Shandong Province, China. The size experiment showed that sea cucumber of all sizes grew throughout the experimental period. Sea cucumbers 20 g ind−1) had no advantage of growth. Sea cucumber sizes of 15–20 g may be suitable for release, considering their higher survival rate and SGR. The density experiment showed that the high biomass group had a low SGR and that the maximum release biomass was 793 g m−2 based on a regression analysis. The optimal practical release season for sea cucumber was spring based on the results of two field experiments.

The VSC-HVDC technology, as the third generation HVDC transmission technology, is proactive and the most advanced transmission technology. The reliability of VSC-HVDC transmission system needs to be further researched since its short research duration and few projects. Based on reviewing VSC-HVDC technology development, this work investigates on the critical factors and equipment affecting normal operation. Then, the article summarizes reliability research status and presents deficiencies by contrasting with the reliability research methods for traditional HVDC transmission. Finally, combining with engineering example, some ideas and prospects for the application and development of VSC-HVDC reliability technology are proposed.

In this paper a segmentation algorithm for cucumber images is presented to solve the problems of target identification and position for a greenhouse cucumber‐harvesting robot. Amethod of combining the three basic colours, branch‐quantity and threshold processing is used to enhance the target im ages, increasing the contrast between background and target and reducing the information content of the colour image. The strengthened image is considered as a knowledge system. The cucumber images are then segmented by a classification decision table which is based on a knowledge‐reduction algorithm from rough set theory, choosing the image colour attribute as a condition attribute and standard colour as a decision attribute. The image noise is removed using an expansion algorithm of mathematical morphology. The experimental results show that the proposed algorithm can enhance the image of greenhouse cucumbers and segment the profile of the cucumber image effectively. There is less noise in the image afte...

Queuing is common in urban public places. Automatically monitoring and predicting queuing time can not only help individuals to reduce their wait time and alleviate anxiety but also help managers to allocate resources more efficiently and enhance their ability to address emergencies. This paper proposes a novel method to estimate and predict queuing time in indoor environments based on WiFi positioning data. First, we use a series of parameters to identify the trajectories that can be used as representatives of queuing time. Next, we divide the day into equal time slices and estimate individuals' average queuing time during specific time slices. Finally, we build a nonstandard autoregressive (NAR) model trained using the previous day's WiFi estimation results and actual queuing time to predict the queuing time in the upcoming time slice. A case study comparing two other time series analysis models shows that the NAR model has better precision. Random topological errors caused by the drift phenomenon of WiFi positioning technology (locations determined by a WiFi positioning system may drift accidently) and systematic topological errors caused by the positioning system are the main factors that affect the estimation precision. Therefore, we optimize the deployment strategy during the positioning system deployment phase and propose a drift ratio parameter pertaining to the trajectory screening phase to alleviate the impact of topological errors and improve estimates. The WiFi positioning data from an eight-day case study conducted at the T3-C entrance of Beijing Capital International Airport show that the mean absolute estimation error is 147 s, which is approximately 26.92% of the actual queuing time. For predictions using the NAR model, the proportion is approximately 27.49%. The theoretical predictions and the empirical case study indicate that the NAR model is an effective method to estimate and predict queuing time in indoor public areas.

The latest research of automobile ABS detection is devoted to create the test site with a special mix adhesion road, there is not currently a practical method of detection and performance evaluation for automobile ABS device, however ABS detection is an important one of automobile comprehensive performance detection, so the ABS detection method is researched on based on test-bed in the paper. The paper puts forward the method of stepless electricity simulation of the automobile inertia mass on the base of test-bed, and sets up mathematical model of that, then design the fuzzy control system of automobile test-bed, finally pointing to the method of electricity simulation, make a compare analysis to practical experiment data from the test site by SIMULINK simulation language.

In this paper, we considered the request of Call Admission Control (CAC) for re-connection and multi-traffic business in order to improve the Quality of Service (QoS) of system, and proposed an CAC algorithm based on the priority re-connection and multi-traffic business service thresholds, named Re-Connection Priority Dynamic Call Admission Control (R-DMCAC), which dynamically adjusts service thresholds according to the system load. Simulation results showed that compared with existing fixed schemes, the proposed scheme can not only guarantee the priority of traffic, but also maintain better performance with the real-time changes of the traffic volume, and improved the QoS of system.

It is vital to improve knowledge integration efficiency for sake of team effectiveness. Informal control could adjust knowledge with different characteristic through people's view instead of formal intervention. Based on combination of Williamson's transaction theory and knowledge based view, this paper suggested three types of trust orientation inclusive of market type, authority type and consensus type and analyzed the role of trust orientation in governing team knowledge integration. Finally, result if empirical study indicated that interdependency and tacitness of knowledge could be governed by trust, while appropriate not; consensus trust had the greater impact than authority trust, however, market trust could not have significant effects.

The evolution mechanism model for core rigidities was put forward in complex adaptive system perspective. It indicated that, the dynamic of core rigidities was rooted from the interaction between the legitimate system and the shadow system, while controlling parameters (information flow speed, diversity degree of members, contact level of members, power diversity and anxiety repression) were the conditions of evolution. Once parameters reached the critical value, the organization would enter the creative space from the stable zone. In case the shadow system was able to implement double-loop study, new core rigidities would emerge, and the legitimate system was replaced by the shadow system accordingly. Therefore, the organization would enter the higher level stable zone, and reinforced new core rigidities. With increase in the values of controlling parameters, core rigidities would encounter spiral ascendance evolution.

It was indicated that the fundamental approach of overcoming core rigidities was to enable firm to operate in the creative space in the view of complex adaptive system (CAS). Therefore, we built measure index system of creativity in the firms and collected data by questionnaire to test the relations between control parameters of creative space and innovation performance of the firms. The results showed anxiety-restraining level and diversity of group members had significant positive relations with product innovation, while anxiety-restraining level had significant positive relations with process innovation and information flow rate had fair.

Trust mechanism always has two popular architectures: centralized fashion and distributed fashion. However, those two architectures are not well suited for multi-agent system since they cannot achieve the trust management autonomy. To achieve the trust management autonomy, the paper presents an autonomous reliable construction model based on Bayesian method. The presented model adopts the Bayesian method to evaluate the trust value of each agent. Every agent can implement trust management autonomously. The simulation experiment results prove that the autonomous trust construction is effective.

There exist knowledge carrier and path dependency approaches of studying core rigidities based on based on traditional scientific paradigm with linear thought as the guideline. This paper, however, built the measure index system of the firm's core rigidities in the perspective of complex adaptive system, insisting the firm consists of legal and shadow systems. Through collecting data by questionnaire, we applied grey target theory into analyzing core rigidities' influential factors in high-tech firms and rank the order of the four firms according to core rigidities. Research demonstrated that the shadow system's support for human resources sub-system, culture sub-system, and organizational structure sub-system has significant influence on the high-tech firm's core rigidities, while the shadow system's support for strategy sub-system, assets sub-system and technology sub-system has not.

Aiming at the bending angle limit of existing pneumatic bending joints at low pressure,an idea of using structural angle to implement the bending action is proposed.And a new type of pneumatic bending joints with two flexible pneumatic actuators(FPAs) as its drive source is designed.This joint includes one T-type structure,two rotating structures which can perform circular motion around the hinge,and two symmetrical FPAs.And two symmetrical FPAs are fixed on the T-type structure and the rotating structure.The two FPAs stretch to push rotating structure to move when inner air pressures are changed,which leads to an angle between rotating structures,and thus bending motion of the joints is achieved.The static characteristics of the turning end of FPA on the bending joint are analyzed based on the moment equilibrium principle.Simulation analysis and experimental results show that angle-pressure ratio of the new pneumatic bending joint is higher than traditional ones.It means that the larger bending angle can be gotten at lower pressure.Besides,the bending angle of the bending joint is nonlinear with the air pressure inside the FPA and the bending angle changes with the structure parameters.