园林养护智能管理系统设计与开发

为解决目前园林养护管理中信息管理系统功能单一、应用技术较简单和养护人员专业知识缺乏的问题,本文利用环境感知技术、远程测控技术、网络通讯技术等信息技术,融合园林植物模型与园林专家知识,设计开发园林养护智能管理系统,该系统实现了园林环境内光、温、水、肥等环境数据及现场图像视频信息的实时采集、预警通知和智能管控等功能,对于提升园林养护自动化水平,提高人员工作效率、降低养护成本,实现园林科学管理和综合管理具有重要意义。

Large-diameter indium antimonide microwire based broadband and robust optical switch

Various nanophotonic devices based on semiconductor wires with a diameter of several ten nanometers have been studied.Nevertheless,studying the optoelectronics properties and performance of such devices based on large-diameter wires is interesting and meaningful.Here,we successfully grew the micronsized indium antimonide(InSb) wires,and examined their nonlinear optical properties by Z-scan and I-scan(power-dependent) methods within the wavelength range of 0.8-2.8 μm.Furthermore,we demonstrated InSb micro wires(MWs) working as an effective and robust optical switch within 1-2.8 μm wavelength.The findings can open possibilities for research on more large-diameter MWs made from other semiconductor materials for photonic and electronic devices.

Tunable and scalable broadband metamaterial absorber involving VO2-based phase transition

Optical absorbers with dynamic tuning features are able to flexibly control the absorption performance, which offers a good platform for realizing optical switching, filtering, modulating, etc. Here, we propose a thermally tunable broadband absorber applying a patterned plasmonic metasurface with thermo-chromic vanadium dioxide (VO2) spacers. An actively tunable absorption bandwidth and peak resonant wavelength in the region from the near-to mid-infrared (NMIR) are simultaneously achieved with the insulating.metallic phase transition ofVO2·Moreover, the scalable unit cell,which is composed of multi-width sub-cells, provides a new freedom to further manipulate (i.e., broaden or narrow) the absorption bandwidth while maintaining a high relative absorption bandwidth and efficient absorbance at the same time. For both transverse-electric and transverse-magnetic polarizations, the proposed nanostructure exhibits a high absorption over a wide angular range up to 60°.This method holds a promising potential for versatile utilizations in optical integrated devices,NMIR photodetection, thermal emitters, smart temperature control systems,and so fbrth.

Nanosecond-pulsed, dual-wavelength, passively Q-switched ytterbium-doped bulk laser based on few-layer MoS2 saturable absorber

A compact saturable absorber mirror（SAM） based on few-layer molybdenum disulfide（MoS2） nanoplatelets was fabricated and successfully used as an efficient saturable absorber（SA） for the passively Q-switched solid-state laser at 1 μm wavelength. Pulses as short as 182 ns were obtained from a ytterbium-doped（Yb:LGGG） bulk laser Q-switched by the MoS2 SAM, which we believe to be the shortest one ever achieved from the MoS2 SAs-based Q-switched bulk lasers. A maximum average output power of 0.6 W was obtained with a slope efficiency of 24%,corresponding to single pulse energy up to 1.8 μJ. In addition, the simultaneous dual-wavelength Q-switching at 1025.2 and 1028.1 nm has been successfully achieved. The results indicate the promising potential of few-layer MoS2 nanoplatelets as nonlinear optical switches for achieving efficient pulsed bulk lasers.

Plane Analysis for an Inclusion in ID Hexagonal Quasicrys tai Using the Hyp er singular Integral Equation Method

A model of a thin elastic inclusion embedded in an infinite ID hexagonal quasicrystal is discussed. The atomic arrangements of the matrix and the inclusion are both periodic along the xi-direction and quasiperiodic along the a;2-direction in the oxiX2-coordinate system. Using the hypersingular integral equation method, the inclusion problem is reduced to solving a set of hypersingular integral equations. Based on the exact analytical solution of the singular phonon and phason stresses near the inclusion front, a numerical method of the hypersingular integral equation is proposed using the finite-part integral method. Finally, the numerical solutions for the phonon and phason stress intensity factors of some examples are given.

Revealing photon transmission in an ultraviolet reactor: Advanced approaches for measuring fluence rate distribution in water for model validation

Fluence rate(FR) distribution(optical field) is of great significance in the optimal design of ultraviolet(UV) reactors for disinfection or oxidation processes in water treatment. Since the1970 s, various simulation models have been developed, which can be combined with computational fluidic dynamic software to calculate the fluence delivered in a UV reactor. These models strive for experimental validation and further improvement, which is a major challenge for UV technology in water treatment. Herein, a review of the simulation models of the FR distribution in a UV reactor and the applications of the current main experimental measurement approaches including conventional flat-type UV detector, spherical actinometer,and micro-fluorescent silica detector(MFSD), is presented. Moreover, FR distributions in a UV reactor are compared between various simulation models and MFSD measurements.In addition, the main influential factors on the FR distribution, including inner-wall reflection, refraction and shadowing effects of adjacent lamps, and turbidity effect are discussed,which is helpful for improving the accuracy of the simulation models and avoiding dark regions in the reactor design. This paper provides an overview on the simulation models and measurement approaches for the FR distribution, which is helpful for the model selection in fluence calculations and gives high confidence on the optimal design of UV reactors in regard to present methods.

A simple experimental scheme for M-QAM optical signals generation

A simple scheme to generate optical quad- rature amplitude modulation （QAM） signals is proposed based on different types of delay interferometers （Dis）. The simulated results show that 16QAM, 64QAM and 256 QAM optical signals can be generated by 2×2, 3 ×3 and 4×4 DI, respectively, and the outputs of the proposed scheme are similar to those of the conventional schemes. The operation principle is discussed and the transmission properties of the square 16QAM as well as 64QAM signals are analyzed and compared with common approach.