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The Qilian Mountain Ecological Zone has an important location and rich biodiversity. It is the source of the main water resources in Jiuquan City. In order to improve the disaster prevention and mitigation capabilities of Jiuquan City, improve the Qilian Mountains' ecological environmental protection capabilities, provide ecological meteorological disaster monitoring, forecasting, and early warning services, use regional weather station observation data and satellite remote sensing monitoring technology to integrate high spatial resolution image data and geographic. The information system is closely integrated, and extensive ecological monitoring has been carried out in the areas of snow cover, grassland vegetation, and reservoir capacity in the middle and western sections of the Qilian Mountains. It has also played a role in monitoring and evaluating artificial weather modification in Jiuquan City.The production of Jiuquan Eco-Meteorological Monitoring Bulletin application products through data analysis and evaluation provides a scientific basis for the ecological environmental protection and restoration of Qilian Mountains, further promotes and guarantees the rapid development of local economic and social science, and strengthens the construction and service of meteorological undertakings.

User attribute inference plays an important role in personalized recommendation and precision marketing. However, in large-scale social networks, user attributes are often missing. To address the problem, this paper introduces an inference framework for deriving missing attributes of users in largescale social networks. We use Sina Weibo as our experimental platform. The framework leverages various collaborative filtering methods and a similarity learning scheme to infer missing user attribute values. Experimental results demonstrate the proposed framework is able to generate satisfactory inference results.

Electric propulsion systems, such as ion thrusters and Hall thrusters, are widely utilized in aerospace. The target indirect measurement method (TIMM) is a simple and robust way to measure its thrust. In general, one can obtain the thrust by scaling up the force exerted on the target surface immersed in the plume flow. However, the charge exchange (CEX) allows ions to become neutral particles, increasing the scaling coefficient. Meanwhile, the sputtered atoms and reflected incident particles exert force on the target surface and enlarge the measured thrust. In this study, the effects of the CEX, the sputtering, and the reflection on the TIMM are mathematically quantified, and then a modified model of the TIMM is proposed. Besides, the thrusts of the LIPS-200 and LIPS-300 ion thrusters were separately measured using the TIMM with the modified model, and the measured thrusts are in good agreement with the rated thrusts. Under the test conditions, the results of the LIPS-300 ion thruster show that the fast neutral atoms produced by the CEX account for more than 20% of all fast particles impacting on the target, and the force caused by the sputtered atoms is about 3.4% of the total force exerted on the target. We discuss how test conditions affect the CEX, sputtering, and reflection, thereby influencing the TIMM. The modified model was also validated through the simulation results, by showing that the measured thrust cannot be influenced by the test conditions.

A thermostatic E × B probe is designed to protect the probe body from the thermal effect of the plasma plume that has a significant influence on the resolution of the probe for high-power electric thrusters. An active cooling system, which consists of a cooling panel and carbon fiber felts combined with a recycling system of liquid coolants or an open-type system of gas coolants, is employed to realize the protection of the probe. The threshold for the design parameters for the active cooling system is estimated by deriving the energy transfer of the plasma plume-probe body interaction and the energy taken away by the coolants, and the design details are explained. The diagnostics of the LIPS-300 ion thruster with a power of 3 kW and a screen-grid voltage of 1450 V was implemented by the designed thermostatic E × B probe. The measured spectra illustrate that the thermostatic E × B probe can distinguish the fractions of Xe+ ions and Xe2+ ions without areas of overlap. In addition, the temperature of the probe body was less than 306 K in the beam region of the plasma plume during the 200-min-long continuous test. A thermostatic E × B probe is useful for enhancing the viability and versatility of equipment and for reducing uneconomical and complex test procedures.

Vibrio parahaemolyticus(VP)is a pathogen of bacterial food poisoning associated with shellfish.VP,which is detected both in human and fish,has even higher concentrations in oysters and other filter-feeding shellfish.In order to study the relationship of VP densities versus water quality factor including water salinity,temperature,pH and dissolved oxygen in the course of oyster culture,we detected total VP densities in the oyster and water quality factor at the oyster farm in Yangxi,Guangdong from March to November in 2009.The results showed that the detection ratio of total VP in oysters was 94.38%.The water temperature was correlated positively with total VP in oysters,but the salinity was correlated negatively with total VP in oysters.The dissolved oxygen and pH didn't show correlation with total VP in oysters.Based on the regression analysis,a quadratic relationship for VP densities versus water temperature and salinity was found.The regression equation of VP densities versus water temperature was:LgVP=0.093T-0.685(R2=0.336);The regression equation of VP densities versus salinity was:LgVP=1.199+0.116S-0.004S2(R2=0.217);The best fit regression equation of VP densities versus water temperature and salinity was LgVP=-1.941+0.116T+0.058S-0.001S2(R2=0.414).The results of this paper may provide some reference data for the risk analysis of VP during oyster culture.