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A two-year (2020-2021) field experiment was conducted at the National Agricultural Environmental Station for Agricultural Environment in Fuxin. The experiment was conducted in a completely randomized block design, consisting of five sowing dates with three furrow depths each year. Seeds were sown on April 11 (T1), April 18 (T2), April 25 (T3), May 2 (T4) and May 9 (T5), respectively, in 2020, and were sown on April 18 (T2), April 25 (T3), May 2 (T4), May 9 (T5) and May 16 (T6), respectively, in 2021. The furrow depths including 5cm (D0, convention planting as the control), 10cm (D1) and 20cm (D2), respectively. By measuring above-ground dry matter, grain yield and yield components, soil water content on the sowing and harvesting day, and soil water storage and maize water use efficiency were calculated, so as to explore the rule of dry matter accumulation and allocation of spring maize, and the changes in resource utilization efficiency under the influence of sowing dates and furrow depths. Both contribute to optimize the cultivation technology of spring maize by selecting suitable sowing date and furrow depth in semi-arid region. The results showed that the sowing dates from April 18 to May 2 were beneficial to the accumulation of above-ground dry matter. Compared with the average of other sowing dates, the maturity period was increased by 8.0%, and promoted the allocation of dry matter to ear weight, with an average yield 9.9% higher than other sowing dates. The water use efficiency was significantly improved. The production efficiency of solar radiation, growing degree days, and rainfall increased first and then decreased with the delay of sowing date. The above-ground dry matter and panicle ear weight were D2>D1>D0 in different furrow depth treatments at the maturity stage. The grain yield of D2 and D1 treatments was significantly higher than that of D0 (11.1% on average), and there was a significant difference in water use efficiency in 2020. Considering yield, resource utilization efficiency and variation coefficient of yield, authors concluded that suitable sowing dates(April 25-May 2) and 20cm furrow depth were the most beneficial to high yield and resource utilization efficiency of maize in semi-arid area of western Liaoning. [ABSTRACT FROM AUTHOR]

This paper derived an approximate discrete-time model for a nonlinear 3-DOF tandem-rotor model helicopter in the case of the multirate input and hold, which was accurate to some order in the sampling period. More importantly, the proposed model had more accurate than the classic Euler approximation. It also shows how a particular strategy can be used to approximate the system output and its derivatives in such a way as to obtain a local truncation error, between the output of the resulting sampled-data model and the true continuous-time system output, of order T5, where T is the sampling period. It also gave an insight interpretation of the obtained sampled-data model can be made in terms of sampling zero dynamics, and their explicit characterization. Moreover, it shows a condition which assures the stability of the sampling zero dynamics for the resulting model helicopter. [ABSTRACT FROM AUTHOR]

Based on the LS-SVM theory,raised its application for prediction residential house's damage against blasting vibration of open pit mining. Ten indexes, I. e. , blasting vibration amplitude, dominant frequency, dominant frequency duration, gray joints intensity, the rate of brick walls, height of housing, roof forms, the structural column of circle beam, the quality of construction and site conditions, were used as blasting vibration prediction of residential house's damage discriminating factors. With the engineering practice test data for the training sample, built the LS-SVM forecasting model of residential house' s damage against blasting vibration of open pit mining. A LS-SVM model was obtained through training 32 measured data of blasting vibration. The re-substitution method was introduced to verify the stability of LS-SVM model(false rate was 0)and was used to discriminate 12 new samples, test results was good. The results show that the ratio of mis-discrimination is lower, and the prediction results are identical with actual results. The LS-SVM model has good classifying performance, high predicted accuracy and can be used in practical blast engineering. [ABSTRACT FROM AUTHOR]

The smoothing-type algorithm has been successfully applied to solve various optimization problems. Based on a new class of smoothing functions, in this paper, we propose a smoothing-type algorithm with a mixed line search for solving the nonlinear complementarity problem. Under suitable conditions, the proposed algorithm is well-defined and maintains global convergence and local superlinear convergence. Preliminary numerical results are also reported and demonstrate the efficiency of the proposed algorithm. [ABSTRACT FROM AUTHOR]

China is a large agricultural country with the most abundant straw resources in the world. In 2010, the amount of collected straw reached 700 million tons, Anaerobic digestion (AD) technology is a widely applied technology can achieve resource utilization of straw, as well as produce clean energy. Straw is one kind of typical carbon-rich biomass, which is easy to acidify in the AD process, even more influence the biogas production and system performance. Additive has the function of adjusting carbon-nitrogen ratio, promoting AD process and relieving acidification process, thus, adding additive has been considered as an alternative method to improve the AD process. In this study, the crushed corn straw were conducted in batch reactor with the feeding concentration of 6%TS at (40±1)°C, urea and inorganic salts soil were used as additives for the straw anaerobic digestion. There are six treatments in this study, including pure straw without adding additive (R1), adding urea with the C/N of 25/1(R2) and 30/1(R3), adding inorganic salts soil of 10 %(R4) and 20% (R5)( based on fresh weight of straw), as well as a control only adding inoculum (R6). The pH value, volatile fatty acids (VFAs) concentration, adenosine triphosphate (ATP) concentration, biogas production and other indicators had been measured in the whole process of 49 days. Acidification phenomenon occurred in the second day for all the treatments and 300mL of cultivated inoculum was added for each treatment. The results indicated that adding inorganic salts soil and urea displayed significant buffering action to the straw anaerobic digestion process. The pH value of R1-R5 ranged at 6.11-6.60 6.69-7.09 6.60-7.16 6.30-7.01 and 6.39-6.97 from the third day to the seventh day, respectively. While the VFAs concentration of R1-R5 was 0.38, 0.37, 0.33, 0.22 and 0.17g/L among which, acetic acid accounting for 60.78% 43.82% 57.62% 21.00% and 27.64%, respectively. According to ATP results, the microorganisms quantity might increased by adding the urea and inorganic salts soil. The ATP peak of R1-R5 was 724, 996, 1236, 1040 and 1248nmol/L, respectively. Compared with the pure straw treatment(R1), R2-R5 made microorganisms quantity increased by 2.76×1011, 5.19×1011, 3.20×1011 and 5.31×1011 of per liter digested liquid, For the anaerobic digestion system with acidification problem and low methanobacteria activity, the promoting action of urea and inorganic salts soil may be influenced and weakened. Compared with the pure straw treatment, the more adding amount of urea and inorganic salts soil, the less of the biogas production, however, it could make the gas peaked one day, two days and four days earlier respectively by adding urea (25:1), adding urea (30:1) and adding 10% inorganic salts soil under the anaerobic digestion system with acidification problem and low methanobacteria activity. In short, it is a good solution to avoid acidification problem by adding urea and inorganic salts soil, the amount and regulation method should be further studied. It is helpful to avoid acidification problem and reduce the interference of promoting effects of adding urea and inorganic salts soil by changing the feeding way (like batch feeding way) and strengthening the microorganisms activity. [ABSTRACT FROM AUTHOR]