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The Anthropocene proposal suggested that the Earth may have entered a new geological epoch, in which human activity and climate change are influencing the environment at global scale. Arrival of the Anthropocene is bringing an unprecedented challenge to the biodiversity that is essential to humans, and enhancing many benefits of nature to human being. However, biodiversity loss is aggravating in the rhythm of inevitable change in the Anthropocene, and the adaptation of biodiversity to the anthropogenic disturbance seems unable to keep pace with the human activity and climate change. Therefore, re-examination of the assumptions and practices upon the current conservation endeavor are needed. We suggested that biodiversity conservation should be paid more attention to the response from biodiversity to the human activity and climate change in the Anthropocene. Thus, the concept of biodiversity arks in the Anthropocene is proposed, that is, biodiversity arks in the Anthropocene are the areas where vulnerable biodiversity is sheltered to alleviate human activity and buffered from climate change under the anthropogenic disturbance. The concept should be implemented for biodiversity conservation to fill gaps between our knowledge and build on successful conservation and sustainability in the Anthropocene. It will be certainly important to conservation policy instruction and management under climate change, especially the implementation of climate buffering zones preserving biodiversity in the face of warming climate.

Life detection radar is widely applied in life detection, especially in situations that demand searching life signal through ruins after disasters. In these circumstances, weak signal feature extraction and analysis are vital technologies. Because of the clutter of environment objects, life signal that received by radar is seriously weak. Traditional methods cannot separate life signal from clutter and noise. This paper propose an algorithm combined with feedback pulse canceller, multiple autocorrelation and synchronous squeeze S-transform (SSST). This method can effectively suppress the clutter and remove the environment noise, then obtain a high-resolution time-frequency distribution. In this way we can make best of life signal feature and classify the type of living target.

Learning in automated negotiations, while successful for many tasks in recent years, is still hard when coping with different types of opponents with unknown strategies. It is critically essential to learn about the opponents from observations and then find the best response in order to achieve efficient agreements. In this paper, we propose a novel framework named Deep BPR+ (DBPR+) negotiating agent framework, which includes two key components: a learning module to learn a new coping policy when encountering an opponent using a previously unseen strategy, and a policy reuse mechanism to efficiently detect the strategy of an opponent and select the optimal response policy from the policy library. The performance of the proposed DBPR+ agent is evaluated against winning agents of ANAC competitions under varied negotiation scenarios. The experimental results show that DBPR+ agent outperforms existing state-of-the-art agents, and is able to make efficient detection and optimal response against unknown opponents.

This paper proposes a multi-robot formation control algorithm. The controller is designed by the difference between the distance and the angle of the two robots. It is proved that the algorithm can guarantee the stability of the formation. Furthermore, the obtained formation control algorithm is tested on the software platform and Pioneer3-DX platform. According to the multi-robot formation control algorithm, a control method of adaptive parameters is proposed. The existing parameters are replaced by fitting equations, which improves the efficiency of parameter adjustment. Simulation and experimental results verify the feasibility and effectiveness of the proposed method.

Electrochemical impedance spectroscopy (EIS) is an effective method for studying electrochemical systems. The interpretation of EIS is the biggest challenge in this technology, which requires reasonable modeling. To overcome the subjectivity of human analysis, this work uses machine learning to carry out EIS model recognition. Raw EIS data and their equivalent circuit models are collected from the literature, and the support vector machine (SVM) is used to analyze these data. Comparing with other machine learning algorithms, SVM achieves the best comprehensive performance in this database. As a result, the optimized SVM model can efficiently figure out the most suitable equivalent circuit model of the given EIS spectrum. This study demonstrates the great potential of machine learning in electrochemical researches.

A novel frequency reconfigurable microstrip antenna based on $({\rm Ba}, {\rm Sr}){\rm TiO}_{3}$ (BST) substrate is presented. Compared to the complicated structures in traditional reconfigurable antennas, our work is featured by a quite concise design. A theoretical model is proposed to calculate the initial antenna parameters. Both the simulation and the experiment indicate that the coupled aperture structure can efficiently overcome impedance mismatch of BST substrate and obtain a frequency tunability of 10% in Ku band by a DC electric field changing from 0 to 10 ${\rm V}/\mu$ m. Besides, similar radiation patterns are obtained in the operating band for both the E plane and H plane. Our study shows that the using of BST material on the frequency reconfigurable antenna is promising, and can be easily extended to reconfigurable antenna arrays.

An optical temperature sensor based on the upconversion luminescence of Tm3+ has been developed. Under a 980 nm diode laser excitation, the fluorescence intensity ratio (FIR) between 700 (Tm3+:3F2,3 → 3H6) and 800 nm (Tm3+:3H4 → 3H6) upconversion emissions from Tm3+/Yb3+ codoped oxyfluoride glass ceramic was studied as a function of temperature in the range of 293–703 K. The 3F2,3 and 3H4 states of Tm3+ are verified to be thermally coupled levels. By using FIR technique, the sensitivity for detecting temperature variations achieved here is better than previous reported rare earth ions fluorescence based temperature sensors. With the advantages of intense upconversion luminescence and absolutely separated 700 and 800 nm emission bands, the Tm3+/Yb3+ codoped oxyfluoride glass ceramic is a very promising candidate for accurate optical temperature sensors with much higher sensitivity and resolution.

A composite ceramic with nominal composition of 45.0 wt%(Ba0.5Sr0.5)TiO3–55.0 wt%MgO (acronym is BST–MgO) is sintered for fabricating a frequency reconfigurable aperture-coupled microstrip antenna. The calcined BST–MgO composite ceramic exhibits good microwave dielectric properties at X-band with appropriate dielectric constant ɛr around 85, lower dielectric loss tan δ about 0.01, and higher permittivity tunability 14.8% at 8.33 kV/cm. An ultrahigh E-field tunability of working frequency up to 11.0% (i.e., from 9.1 GHz to 10.1 GHz with a large frequency shift of 1000 MHz) at a DC bias field from 0 to 8.33 kV/cm and a considerably large center gain over 7.5 dB are obtained in the designed frequency reconfigurable microstrip antenna. These results demonstrate that BST materials are promising for the frequency reconfigurable antenna.

Fe27.45Co30.19B42.36 (referred to as FeCoB) films with 100 nm in thickness were co-sputtered on (011)-cut lead zinc niobate-lead titanate (PZN-PT) single crystal substrate under RF powers of 80 W for Fe50Co50 target and 120 W for B target, respectively. The anisotropy field HK of the FeCoB/PZN-PT multiferroic composite is increased by more than 10 times, from 56 to 663 Oe under the E-field from 0 to 7 kV/cm due to the strong magnetoelectric coupling, corresponding to a large tunability of HK of 86.7 Oe cm/kV. At the same time, the self-bias ferromagnetic resonance frequency fFMR is dramatically shifted upwards by an electric field from 2.57 to 9.02 GHz with an increment of 6.45 GHz, corresponding to E-field tunablity of fFMR 921.4 MHz.cm/kV. These features demonstrate that FeCoB/PZN-PT multiferroic laminates prepared under an integrated circuits process are promising in fabrication of E-field tunable monolithic microwave integrated circuits (MMIC) devices and their components.

A prototype automated inspection system was developed to classify apples based on bruising in real time. Raman spectroscopy was used for apple bruise testing. Fifty ‘Delicious’ apples were randomly divided into two groups, 25 apples for light bruise group (falling height 50 mm), and 25 for heavy bruise (falling height 300 mm); each group was divided into a modeling set and a testing set. A Nicolet FT-Raman Spectroscope was employed to obtain apple spectra. The Spectrascope utilized OMNIC E. S. P. 5.1 software. The unbruised and bruised spectra were analyzed and classified by WinDAS using canonical variate analysis (CVA) and principle component analysis (PCA) models, on both the training and testing sets. The PCA and CVA model analysis satisfactorily classified the apples by bruise. Therefore, the results show that the Raman spectroscope permits non-destructive bruise determination with good results.

The Co2FeSi films are deposited on Si (100) substrates by an oblique sputtering method at ambient temperature. It is revealed that the microwave ferromagnetic properties of Co2FeSi films are sensitive to sample position and sputtering power. It is exciting that the as-deposited films without any magnetic annealing exhibit high in-plane uniaxial anisotropy fields in a range of 200 Oe–330 Oe (1 Oe = 79.5775 Am−1), and low coercivities in a range of 5 Oe–28 Oe. As a result, high self-biased ferromagnetic resonance frequency up to 4.75 GHz is achieved in as-deposited oblique sputtered films. These results indicate that Co2FeSi Heusler alloy films are promising in practical applications of RF/microwave devices.

Ho(3+)/Yb(3+) codoped glass ceramic was prepared by melt-quenching and subsequent thermal treatment. Under a 980 nm diode laser excitation, upconversion emissions from Ho(3+) ions centered at 540, 650, and 750 nm were greatly enhanced compared with those in the precursor glass. Especially, the short-wavelength upconversion emissions centered at 360, 385, 418, 445, and 485 nm were successfully obtained in the glass ceramic. An explanation for this phenomenon is given based on the fluorescence decay curve measurements. In addition, an optical temperature sensor based on the blue upconversion emissions from (5)F(2,3)/(3)K(8)→(5)I(8) and (5)F(1)/(5)G(6)→(5)I(8) transitions in Ho(3+)/Yb(3+) codoped glass ceramic has been developed. It was found that by using fluorescence intensity ratio technique, appreciable sensitivity for temperature measurement can be achieved by using the Ho(3+)/Yb(3+) codoped glass ceramic. This result makes the Ho(3+)/Yb(3+) codoped glass ceramic be a promising candidate for sensitive optical temperature sensor with high resolution and good accuracy.

Under 980 nm excitation, the temperature-dependent green upconversion emissions from Er3+/Yb3+-codoped CaWO4 phosphor were studied at temperatures from 294 to 923 K. By using the fluorescence intensity ratio technique, the maximum sensitivity for temperature measurement achieved here is approximately 0.0092 K-1, which is much higher than previously reported temperature sensors based on the fluorescence of Er3+ ions in other host materials. With the efficient upconversion fluorescence, the Er3+/Yb3+-codoped CaWO4 is a very promising candidate for optical high-temperature sensors with high sensitivity and good accuracy.