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Open educational resources (OER) are important assets for students or teachers, used to help them search for useful resources. However, it is a challenge to improve the user engagement of OER. In this paper, we propose a system, called resource delivery service system (RDSS), in the Taiwan Open Platform for Educational Resources (TOPER) that actively recommends educational resources to users. RDSS...
We demonstrated a GaN-InGaN core-shell nanorod periodic array lasing under room temperature. Optical simulations and photoluminescence measurement revealed optically-coupled whisper gallery modes. The threshold pumping density was 80 kW/cm2 with a quality factor of 1940.
The most of Chinese high-speed railway lines are using CTCS-3 train control system to ensure the safety of the train. In the CTCS-3 train control system, the way of the location for on-board equipment is different from the ground equipment. The way of location for on-board equipment is based on the balise positioning and speed transmitter, but the ground equipment is based on the track circuit. Due...
Since convolutional neural network (CNN) lacks an inherent mechanism to handle large scale variations, we always need to compute feature maps multiple times for multiscale object detection, which has the bottleneck of computational cost in practice. To address this, we devise a recurrent scale approximation (RSA) to compute feature map once only, and only through this map can we approximate the rest...
The quasi-Z-source cascaded multilevel inverter is a new type of inverter topology that can achieve buck/boost and DC-AC conversion in single-stage system and output multi-level voltage. When it is applied to distributed grid-connected generation, a big output power difference between modules will lead to grid-connected current distortion and system instability. In this paper, the output power ratio...
This paper shows the design of a 2-DOF exoskeleton simulating ball and socket joint, for use on the human shoulder. This design is based on the natural movement of the human shoulder wich has a ball and socket joint. In addition, will be a dynamic and control analysis.
The Quasi-Z-Source inverter (qZSI) applied to the photovoltaic (PV) system has nonlinear and unstable zero dynamic characteristics, which leads to the problem of narrow system bandwidth and slow dynamic response. A nonlinear control strategy is proposed based on the input-output feedback linearization method. The nonlinear affine model of qZSI is presented and transformed to a linearized and decoupled...
For the rationality of optimization of 126kV SF6 circuit breaker opening and closing, it calculates and analyzes the matching characteristics of circuit breaker and motor drive mechanism. And then, the corresponding relationship between the contact movement and the permanent magnet motor is obtained. The contact speed of circuit breaker is mainly determined by the rotation speed of permanent magnet...
As O-ring is widely used in GIS, research of its aging and operating life is helpful to the maintenance of GIS. In order to study the aging of O-ring and its compression set after aging, a method of aging experiment was designed. The experiment was carried out according to the method, and the results at different temperatures were collected. A data processing method is also introduced, and the results...
The permanent magnet direct-driven motor for high voltage circuit breaker should not only meet the requirements of the speed, high starting torque and dynamic response ability, but also to meet the mechanical life requirements of the operation. In this paper, a new type of permanent magnet synchronous motor based on V-type structure is presented. It is shown by theoretical analysis and parameters...
Circuit breakers are important equipment to control the energy distribution and fault isolation in power grid. With the development of the power grid in China, the evaluation of health status of circuit breaker in operation becomes an important part of the operation management. A number of studies have been made on the evaluation of circuit breaker health status, but are mostly limited to interpretation...
This paper presents, for the first time, the nonlinear distortion characteristics of a Doherty Power Amplifier (DPA) with equal-cell and efficiency range of > 6dB. Theoretical study reveals that, even with ideal transistor, the Doherty circuit exhibits built-in AM/AM and AM/PM nonlinearities due to the presence of complex load modulation. For experimental verification, a 42 dBm, 2 GHz DPA with...
Focused images captured by the lens system suffer image degradation due to factors, such as aberration, caused by the optical structure. In the simple lens system, aberration is more severe because of the simplification of the imaging system. In the existing imaging model, the blur kernel of the image is usually described by the point spread function. A few studies have shown that the blur kernel...
Big data and cloud platform technology continue to develop, making the rapid development of the medical industry, the level of medical electronic higher and higher. Thus, medical data is also more rich mode, incomplete, timing, redundancy characteristics. However, the scientific use of medical data is critical to medical outcomes. In this paper, the characteristics of medical data, the current hotspot...
The human auditory system has the ability of analyzing and recognizing signals. A good algorithm of auditory feature extraction can improve the performance of the speaker recognition system. The algorithm embarks from the simulation of human auditory perspective, and first the Gammatone filter is improved, and the improved filter(Gammatone-4 filter) can be used to more better simulate the human cochlea...
An amplified feedback DFB laser with extended modulation bandwidth is experimentally demonstrated in this paper. All the three sections of laser cavity, including DFB section, phase section and amplified feedback section, have the same active layer, which can avoid the butt-joint re-growth process. The gratings in both DFB section and amplified feedback section are fabricated by the Reconstruction...
Due to its lots of advantages, CT20 type spring operating mechanism is widely used in the 126kV high voltage circuit breaker. This type mechanism should not meet the requirement of higher interrupting capacity circuit breaker while the interrupting capacity is increasing. In this situation, sometimes the vibration of the closing latch during closing may cause the closing process failed if there is...
The design, fabrication and characterization of the integrated optical injection-locked (OIL) DFB lasers are presented. The master laser (ML) and the slave laser (SL) are fabricated on the same chip. The gratings of the ML and SL are designed utilizing the reconstruction equivalent chirp (REC) technique. Thus the fabrication difficulty of the integrated OIL DFB lasers is relaxed using the equivalent...
A major challenge in matching between vision and language is that they typically have completely different features and representations. In this work, we introduce a novel bridge between the modality-specific representations by creating a co-embedding space based on a recurrent residual fusion (RRF) block. Specifically, RRF adapts the recurrent mechanism to residual learning, so that it can recursively...
The interoperability testing of CTCS-3 Level Train Control System guarantees the safe operation of train running on different lines. It makes great sense to achieve automatic analysis of interoperability testing results, which could improve the efficiency and accuracy of testing. In this paper, a research was conducted on automatic analysis of testing results for on-board equipment of train control...
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