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An optical fiber immunosensor with a low detection limit based on plasmon coupling enhancement is proposed for detecting human immunoglobulin G (IgG). Graphene oxide (GO)-gold nanorod composites are synthesized and modified onto a photonic crystal fiber (PCF) surface coated with a Au film. GO, as a biosensitive layer, is used to decorate the gold nanorods and concentrate target molecules. The experimental result indicates that the refractive index sensitivity is drastically enhanced to 22248 nm/RIU because of plasmon coupling. Correspondingly, the human IgG detection limit decreases to 6 ng/mL. Moreover, the PCF is insensitive to temperature fluctuation, which can further reduce the measurement error.

A sapphire fiber high temperature sensor based on Fabry-Perot interference was studied in the paper. A sapphire wafer served as the Fabry-Perot cavity was fixed to the end face of the sapphire fiber. The sensor was encapsulated in an alumina ceramic tube-ceramic sleeve structure to improve structural stability. Experiment results showed the sensor had a wide temperature measurement range of 25 °C–1550 °C. The temperature sensitivity reached 32.5 pm/°C at 1550 °C. Furthermore, the temperature was demodulated from the interference spectrum through fast Fourier transform algorithm. It was concluded that the sapphire fiber sensor with advantages of small size, good stability and a wide range of temperature measurement is very promising for measuring high temperature.

Mars surface composition detector (MarSCoDe) is a scientific instrument suite onboard the Mars rover of the “Tianwen-1” mission, which uses laser-induced breakdown spectroscopy and shortwave infrared spectroscopy to detect the composition of soils and rocks at the surface of Mars. The optical head unit (OHU) is the core hardware of MarSCoDe, containing a Cassegrain telescope and other optical modules for lasers generation and signals transmission. The unit lacks thermal control resources and is located outside the rover’s cabin, which will directly face the Martian surface drastic temperature changes. We introduce the optomechanical designs that realize the lightweight and high thermal stability of the OHU optical system, especially the designs and implementations of the semiopen primary mirror based on silicon carbide and the fully closed optical bench based on carbon fiber-reinforced polymer. Meanwhile, the advantages and difficulties of silicon carbide, long carbon fiber-reinforced silicon carbide composites, and carbon fiber-reinforced polymer materials used for small and compact optomechanical systems are discussed. Subsequently, the environmental adaptability of the telescope system of OHU was studied through analytical and experimental methods, which show that it can achieve the required optical performance over a temperature range of approximately 100°C.

A review is presented on high temperature measurement technology based on sapphire optical fiber. This review paper focuses on the sensing theory, sensor structures and sensing performances of different sapphire fiber sensors. Firstly, there is discussion on pyrometer made from sapphire fiber and description on its corresponding sensing properties. Secondly, there are summary on sapphire fiber Bragg grating (SFBG) inscribed by different methods for high temperature measurement. Thirdly, there are analysis on sapphire fiber sensors based on Fabry Perot (FP) interference with different structures. All above, subsequently, lead to the discussion on microwave interferometry and Raman scattering-based sapphire fiber sensors. Then a sensing performance comparison of sapphire pyrometers based on different detection principles are discussed. On the premise of all above, a future prospect and development trend of high-temperature sapphire fiber sensor are addressed as well.

The wing parameters of a subsoiler, such as the location and angle of the wings, have an important impact on the operating performance of the winged subsoilers. To study the comprehensive effect of wing parameters and to determine the optimal parameters of a winged subsoiler, a field experiment was conducted. The experimental factors were the mounting height (50, 100, 150, 200, and 250 mm), sweep angle(5°, 15°, 25°, 35°, and 45°) and mounting angle(5°, 15°, 25°, 35°, and 45°). The draft force of the subsoiler and the disturbed soil area were measured; these two variables defined the Specific Draft Force (SDF). The SDF was used as the response index to evaluate the performance of the winged subsoiler. The mathematical model of regression between experimental factors and SDF was established. The results showed that the normal probability distribution of the predicted and measured values of SDF tended to be linear, indicating that the credibility of the results of the analysis was higher. The mounting height, mounting angle, and sweep angle had interactive effects on SDF. The order of significance was mounting height, mounting angle, and sweep angle. The experimental parameters were optimized by Design-Expert 8.0 software: 124 mm for the mounting height, 45° for the mounting angle, and 45° for the sweep angle. This optimal combination of parameters resulted in a SDF of 69.9 kN/m2. The winged subsoiler designed using the optimization results showed that the average value of SDF was 78.73 kN/m2: significantly lower than SDF (79.34-95.33 kN/m2) before optimization. Keywords: Mounting angle, Mounting height, Optimization, Parameter, Specific Draft Force (SDF), Subsoiler, Sweep angle, Wing.

Mobile object index should support efficient update operations besides efficient query operations. In this paper, we consider the issue of the efficient updating of mobile object index. Based on a model for the mobile data, we introduce a method of incorporating statistical information of the regions covered by the mobile objects into feature vectors. We then propose a novel architecture of mobile object index, where R-tree is used to index the occupied regions instead of the mobile objects themselves and extreme learning machine (ELM) is used to classify the regions. Further, we describe several related algorithms and the update strategy based on the classification of the regions. The proposed strategy and algorithms are evaluated in a simulated environment. The experiments demonstrate that the proposed update strategy based on region classification using ELM can achieve higher performance with respect to I/O operations. Compared to the strategy without region classification, the proposed method can reduce the number of I/O operations more than 80%.

The integration of intelligent spore image sequence capture device is designed for capturing spores and then generates a series of images. Powdery mildew spore is an extremely harmful bacteria spore in agricultural crops. This paper mainly introduced a new method which could realize the automatic detection of the powdery mildew spores. The new method mainly included pre-processing, image segmentation, feature extraction and identification. Pre-processing included illumination compensation, graying, image enhancement. Image segmentation included binary, image smoothing. Finally identification used BP neural network method. Training pictures used 155 pictures and the correct rate was 95.5%. Testing took 89 pictures, and the correct rate was 63.6%. The result proved the validity and correctness of this method.

This paper examines the effectiveness of a computer-based corpus approach to college English writing. The empirical study in this paper illustrates that the use of corpus does benefit college English writing but there are some problems in its application. Pedagogical implications are then provided to enhance the effective integration of corpus and college English Writing: 1) teachers and learners need to negotiate frequently during the whole process of corpus-based DDL; 2) corpus use in writing must adapt to the students’ needs and teaching environments; 3) the alternative use of corpus and dictionaries will enhance the efficiency of corpus-based learning of the students; 4) Integrating cooperative learning and DDL will promote college students’ writing greatly.