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As the carrier of scientific research funding for various organizations, scientific research projects are the main driving force for the development and progress of national science and technology. Performance evaluation of these projects can stimulate the vitality of scientific research, and promote scientific and technological innovation. In order to establish and improve the performance evaluation system of military scientific research projects, this paper studies the performance evaluation indicators from four perspectives: resources, effect, internal business processes, and learning and growth based on the balanced score card.

Under the two-level maintenance mode, in order to scientifically evaluate the maintenance support ability of synthetic brigade under the new system, it is an urgent problem to establish a reasonable evaluation index system. First of all, the mission, organizational structure and equipment characteristics of synthetic brigade under the new situation are analyzed. Then, according to the principle and method of establishing index system, the evaluation index is put forward. Finally, AHP is used to determine the index weight, so as to establish the evaluation index system of actual combat training of equipment maintenance support capability of synthetic brigade under the new system.

Photovoltaic power output forecast error exists objectively and inevitably, and it can provide a guarantee for safe and stable operation of the power system through analyzing its characteristics. In this paper, the influence of predicted output fluctuation characteristics (predicted output amplitude and power variation) on prediction error was studied based on the analysis of variance (ANOVA) method. The prediction error conditions were classified into six types based on the clustering of numerical characteristics of predicted output. Then, a Generalized Gaussian Mixture Model (GGMM) was proposed to fit the prediction error distribution of each type of photovoltaic output. The mean absolute error (MAE), coefficient of determination (R2), and root mean square error (RMSE) were used as accuracy evaluation indexes. The example analysis showed that the GGMM can satisfy the asymmetry and kurtosis diversity of the error distribution after division by conditions, and the fitting result is better than that of the normal distribution, improved Laplace distribution and t Location-Scale distribution model.

The feasibility of battery energy storage system (BESS) in ameliorating power system transient stability has been proved. However, the required BESS capacity is large, which leads to high price. Meanwhile, the improving effect is significantly affected by fault location and BESS location. To address the problem, a distributed configuration of BESS, with a coordinated control method, is proposed in this paper. Firstly, an independent double-closed loop decoupling controller is designed for each BESS, so that the BESS unit can realize decentralized control according to its local correlation information. Secondly, particle swarm optimization is applied to optimize the control parameters of the distributed controllers to achieve coordinated control. Simulation results show that the distributed BESS controllers optimized by particle swarm optimization can better coordinate with each other, and the transient stability of the system is significantly improved.

Potassium Permanganate (KMnO4), which is a kind of strong oxidizer, is used in water production. As KMnO4 containing Manganese, the Manganese concentration may get higher concentration by overdosing additives, however, there isn’t any conclusion of the dosing interval in the present study. This paper used Manganese sand as catalyst and KMnO4 as oxidizer, trying to determine the optimal amount of the oxidizers, the dosing ratio and the dosing limit. The results showed that KMnO4 could remove manganese in drinking water effectively, when the addition ratio was 3.9, the removal efficiency of manganese reached 98%.

In order to understand the seasonal levels, formation mechanism and atmospheric chemical behaviours of water-soluble ions of PM10 in the Yangtze River Delta (YRD) region, aerosol samples were collected from January 2nd to December 28th, 2017 at a WMO/GAW regional background station in Lin’an. The concentrations of PM mass and nine water-soluble inorganic ions were obtained. The annual average concentration of PM10 was 59.9±33.9 μg m−3, lower than those reported in previous studies, indicating air quality of YRD region was improved. Nine water-soluble inorganic ions was accounted for 30.2-45.1% of the total PM mass, while ammonium (NH4+), sulfate (SO42+), as well as nitrate (NO3-) were the major ions which contributed 86.3% to total ions. The NO3- concentration was lowest in summer but highest in winter, suggesting it was likely influenced by thermodynamics. The levels of SO42- in spring and winter were related to photochemical reaction and regional transportation. Except for the SNA, Ca2+ was highest in four seasons likely due to sand storm and road fugitive dust. The annual mean ratio of [NO3-]/[SO42-] was nearly to 1, indicating mobile and stationary sources were equally important in Lin’an. The mean nitrogen oxidation ratio (NOR) and sulfur oxidation ratio (SOR) were 0.22±0.13 and 0.41±0.13, respectively, suggesting secondary formation was significant in the atmosphere at the background station of YRD region.

Path planning is an essential problem in the autonomy research of UAVs. This paper proposes a new path planning algorithm for fixed wing UAVs based on genetic algorithm (GA) and Dubins curve theory. Path planning is treated as a global optimization problem under certain constraints, including the velocity vectors of initial and goal points and the minimum turning radius of UAVs. Dubins curve theory is utilized to satisfy the velocity vector constraints. GA is utilized to generate the shortest threats avoidance path in a 2D environment. A new encoding scheme is proposed, taking into account initial circles, goal circles, threats circles and the positional relationship between the path and these circles. The 2D Dubins path is converted to Dubins airplane path by adding a flight-path angle to it. The algorithm was tested in a complex flight environment and the planned path was tracked by a 6DOF Simulink model of a fixed wing UAV. Results show that the algorithm can generate shortest threats avoidance path in a complicated 3D environment and meanwhile satisfy constraints mentioned above.

The emission characteristics under worldwide harmonized light vehicles test cycle (WLTC) was investigated for a 48V hybrid light-duty vehicle which carried a 2.0 L naturally aspirated engine on engine test bed after the WLTC cycle was converted to the corresponding engine transient cycle. The influence of electric heating catalyst on exhaust emission was analyzed. The results show that electric heating catalyst can effecively speed up the temperature rise rate then significantly decreases the exhaust emission. Electric heating has a more pronounced effect for ceramic carrier catalyst.

In this paper, through the experimental study of two heating seasons, it is found that the heat pump installation position and orientation, circulating pump work/frequency conversion, frosting conditions, etc. have a greater impact on the heat pump unit energy efficiency ratio. According to the actual operation data and theoretical derivation, the analysis shows that the energy efficiency ratio increases by 2.4% when the installation position and orientation increase the air temperature by 1K. The circulating water pump can save 78% of the power consumption in the period by changing the power frequency to frequency conversion. The frosting condition diagram can make a reasonable configuration and operation prediction for the heat pump system.

To ensure the machining accuracy of workpiece, it is necessary to predict the workpiece deformation in machining process through establishing a high precision workpiece deformation forecast model. To solve these problems, a more efficient variable stiffness analysis model is proposed, which can obtain quantitative stiffness value of the machining surface. Applying simulated cutting force in sampling points using finite element analysis software ABAQUS, the single direction variable stiffness rule can be obtained. First of all, finite element simulation model of face milling is established with the Johnson-Cook material model and failure model of 7050 aluminum alloy. Prediction model is established based on SVM and input data is provided by the finite element software ABAQUS simulation. Results show that the model prediction relative error is less than 5%. It is concluded that the effects of milling parameters on workpiece machining deformation and practical guide for production.