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Radio telescopes are important for the development of society. With the advent of China’s Five-hundred-meter Aperture Spherical radio Telescope (FAST), adjusting the reflector panel to improve the reception ability is becoming an urgent problem. In this paper, an active control model of the reflector panel is established that considers the minimum sum of the radial offset of the actuator and the non-smoothness of the working paraboloid. Using the idea of discretization, the adjusted position of the main cable nodes, the ideal parabolic equation, and the expansion of each actuator are obtained by inputting the elevation and azimuth angle of the incident electromagnetic wave. To find the ideal parabola, a univariate optimization model is established, and the Fibonacci method is used to search for the optimal solution h=−0.33018 (offset in the direction away from the sphere’s center) and the focal diameter ratio f=0.4671 of the parabolic vertex. The ideal two-dimensional parabolic equation is then determined as x2−555.25z−166757.2=0, and the ideal three-dimensional paraboloid equation is determined to be z=(x2+y2)/555.25−300.33018. Moreover, the amount of the nodes and triangular reflection panels are calculated, which were determined to be 706 and 1325, respectively. The ratio reception of the working paraboloid and the datum sphere are 9.434% and 1.3898%, respectively. The latter is calculated through a ray tracing simulation using the optical system modeling software LightTools.

Based on the temperature measurement technology of tunable diode laser ab-sorption spectroscopy, the simulation and experimental research on the temperature measurement of CO2 gas emitted by D4114B Diesel engine is realized. The light source model, gas chamber model and data detection model were established by using SIMULINK, which is more general numerical simulation tool in MATLAB. Under the simulated Diesel engine emission environment, the measured CO2 gas temperature was obtained by model simulation and analyzed. The simulation relative error was 0.077%. The marine D4114B Diesel engine was used as the test object, the visual window was reconstructed on the exhaust light path, and an optical path test system was established. The tunable diode laser was used as the detection light source to carry out on-line test research on the CO2 gas temperature in the exhaust gas emission. The relative error was 4.4%. The results show that the model built by SIMULINK can reflect the actual laser modulation effect and CO2 gas absorption. The simulation results have certain reference value for the research of tunable diode laser absorption spectroscopy temperature measurement system.

Represented here is a continuous-wave (CW) operation laser and a passively Q-switch (PQS) Ho:SSO microchip laser with a Cr2+:ZnSe saturable absorber (SA). An end-pumped Tm:YAP laser pumping was employed, which operated at room temperature. Up to our knowledge, it is the first time to report a PQS microchip Ho:SSO laser. A maximum 418 mW CW laser output was realized with an absorbed pump power of 2.5 W. The slope efficiency was 59.4%. In the PQS mode, the maximum output power was 332 mW, at the same time the slope efficiency was down to 57.1%. The maximum repetition frequency was 0.69 kHz. The maximum pulse energy of 481 μJ was realized corresponding to the pulse width of 103 ns. The pulsed characteristics were studied in this work. The output wavelength for different modes were also investigated.

In the industrial targeted poverty alleviation, land circulation is a key process. Based on the national strategy of targeted poverty alleviation, this paper combined the industrial development of targeted poverty alleviation with land circulation. According to the field survey on the current situation of land circulation and promotion of the industrial poverty alleviation in the typical project area of Zhongping Village in Zhongping Town and Jiaowuying Village in Jiulong Town in Luquan Yi and Miao Autonomous County in Yunnan Province, it summarized and analyzed the organization and operation mechanism, basic practices and main results of the land circulation and promotion of industrial poverty alleviation model in the typical project area of the county. It also summarized the innovation and successful experience of the model, and then came up with measures to further promote the implementation of the model, so as to provide necessary reference for the implementation of land circulation and industrial targeted poverty alleviation for the poverty-stricken counties in Yunnan Province and similar provinces (cities, regions).

Due to the severe restrictions of natural conditions and ecological environment, igh-altitude mountainous areas usually become the "hard bones" in the battle against poverty. Xueshan Township, Luquan Yi and Miao Autonomous County of Yunnan Province, located in the alpine valley of Jinsha River, is a major township with wide and deep poverty, and the incidence of poverty is up to 45.00%. In recent years, Xueshan Township has insisted on the battle against poverty, made effort to develop the Codonopsis pilosula industry, and successfully developed a road to poverty alleviation through C. pilosula industry, and formed a unique industrial poverty alleviation model by the end of 2018, the incidence of poverty dropped to 0.74%. Based on field survey and interview, this paper analyzes and summarizes the specific practices, main results, practical experience and promotion and application measures of the poverty alleviation model of C. pilosula planting industry in Xueshan Township, in the hope of providing certain reference for the targeted poverty alleviation in similar areas in Yunnan Province and other provinces of China.

Laser emission performances at 2 μm obtained from a Ho:Sc2SiO5 crystal was reported in this work. A few-layer MoS2 saturable absorber was used to obtain passively Q-switched regime. The laser beam quality was characterized by an M2 factor of 1.13 × 1.11. In continuous-wave mode the laser delivered 3.28 W output power for the pump with 12.58 W at 1.94 μm, which corresponds to an overall optical-to-optical efficiency of 0.26. The slope efficiency was 0.50. The maximum average power was 1.11 W and the laser run at 128.4 kHz repetition rate, indicating pulse energy of 8.62 μJ. The shortest laser pulse duration was measured to be 248 ns from which pulse peak power was determined as 34.77 W.

Both of crop growth simulation models and remote sensing method have a high potential in crop growth monitoring and yield prediction. However, crop models have limitations in regional application and remote sensing in describing the growth process. Therefore, many researchers try to combine those two approaches for estimating the regional crop yields. In this paper, the WOFOST model was adjusted and regionalized for winter wheat in North China and coupled through the LAI to the SAIL–PROSPECT model in order to simulate soil adjusted vegetation index (SAVI). Using the optimization software (FSEOPT), the crop model was then re-initialized by minimizing the differences between simulated and synthesized SAVI from remote sensing data to monitor winter wheat growth at the potential production level. Initial conditions, which strongly impact phenological development and growth, and which are hardly known at the regional scale (such as emergence date or biomass at turn-green stage), were chosen to be re-initialized. It was shown that re-initializing emergence date by using remote sensing data brought simulated anthesis and maturity date closer to measured values than without remote sensing data. Also the re-initialization of regional biomass weight at turn-green stage led that the spatial distribution of simulated weight of storage organ was more consistent to official yields. This approach has some potential to aid in scaling local simulation of crop phenological development and growth to the regional scale but requires further validation.

Evapotranspiration (ET) in regional scale is not only a major component of energy and water balance, but also a linking medium between ecological system and climatic system. Due to the increased needs from hydrological, climatological and ecological communities, more interest has been paid on developing algorithms to estimate ET over larger scales by means of combining remote sensing measurements of land surface parameters during the last decades. Compared to all previous remote sensing algorithms for heat fluxes estimations, the Surface Energy Balance System (SEBS) developed by Su (2002) has the most important advantage of its inclusion of a physical model for the estimation of the roughness height for heat transfer which is the most critical parameter in the parameterization of heat fluxes of land surface. In this paper, first, SEBS has been utilized to estimate the surface fluxes over HuangHuaiHai Plain in Northern China by using MODIS/TERRA images, in combination of meteorological data collected in meteorological stations distributed over the study area. The estimated fluxes by SEBS in clouds free days are first compared with the measurements from QRSLSP/Shunyi Campaign near Beijing (Liu et al.2002) and then compared to the measurements by Large Aperture Scintillometers (LAS) in Zhengzhou LAS station located in Henan Province, China. Both the comparisons show that the estimated fluxes from SEBS have a good agreement with the measurements. Based on the validation of the model, an extended modular of SEBS has been utilized to estimate daily ET over the study area and the results showed that the extended SEBS can be used to estimate daily ET over regional scale. Finally, limitations and special care in using SEBS are discussed.