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Recent advances in molecular biology research of a rice pest, the brown planthopper

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Journal of Integrative Agriculture 2019年第4期18卷 716-728页

作者： bao yan-yuan ZHANG Chuan-xi State Key Laboratory of Rice Biology and Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insects Institute of Insect Sciences Zhejiang University

The brown planthopper, Nilaparvata lugens St?l, has become a major threat in tropical Asian and China since the rice green revolution of the 1960 s. Currently, insecticide application remains the primary choice for controlling this rice insect pest, but heavy use of insecticides poses dangerous risks to beneficial natural enemies and pollinators, and stimulates N. lugens reproductivity, and has caused a resurgence of the pest in the major rice-planting regions throughout Asia. Achieving the long-lasting goal of sustainable management of N. lugens requires understanding of the molecular basis of outbreaks of the pest and the development of environment-friendly pest-control strategies. Here, we review the recent molecular advances in N. lugens research on the aspects of its endosymbionts, virus transmission, insecticide resistance, and interaction between N. lugens and rice plants. We also put forward further research directions that may shed some lights on management of the rice pest.

关键词： Nilaparvata lugens endosymbionts virus transmission insecticide resistance interaction with rice biological management

A method for observing the three-dimensional morphologies of inclusions in steel

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International Journal of Minerals,Metallurgy and Materials 2012年第2期19卷 111-115页

作者： yan-ping bao Min Wang Wei Jiang State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing 100083 China Journals Publishing Center University of Science and Technology Beijing Beijing 100083 China

A method for observing the three-dimensional morphologies of inclusions by deeply eroding a steel sample with a kind of organic solution composed of bromine water, acetone, and HCl （volume ratio, 45：45：10） was introduced. Four different kinds of inclusions in ultra low carbon steel were compared by metallographic observation and erosion observation. The results show that the three-dimensional morphologies of different kinds of inclusions could be observed clearly and simply after erosion. The method is useful for the observation and analysis of inclusions made by deep erosion. It also provides a new way to control and remove inclusions based on the true morphologies of inclusions.

关键词： inclusions morphology erosion ultra low carbon steel

Cleanliness of Ti-bearing Al-killed ultra-low-carbon steel during different heating processes

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International Journal of Minerals,Metallurgy and Materials 2017年第12期24卷 1370-1378页

作者： Jian-long Guo yan-ping bao Min Wang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

During the production of Ti-bearing Al-killed ultra-low-carbon(ULC) steel, two different heating processes were used when the converter tapping temperature or the molten steel temperature in the Ruhrstahl–Heraeus(RH) process was low: heating by Al addition during the RH decarburization process and final deoxidation at the end of the RH decarburization process(process-Ⅰ), and increasing the oxygen content at the end of RH decarburization, heating and final deoxidation by one-time Al addition(process-Ⅱ). Temperature increases of 10°C by different processes were studied; the results showed that the two heating processes could achieve the same heating effect. The T.[O] content in the slab and the refining process was better controlled by process-Ⅰ than by process-Ⅱ. Statistical analysis of inclusions showed that the numbers of inclusions in the slab obtained by process-Ⅰ were substantially less than those in the slab obtained by process-Ⅱ. For process-Ⅰ, the Al_2O_3 inclusions produced by Al added to induce heating were substantially removed at the end of decarburization. The amounts of inclusions were substantially greater for process-Ⅱ than for process-Ⅰ at different refining stages because of the higher dissolved oxygen concentration in process-Ⅱ. Industrial test results showed that process-Ⅰ was more beneficial for improving the cleanliness of molten steel.

关键词： low carbon steel cleanliness RH process heating inclusions

Dissipativity Analysis of Neural Networks with Time-varying Delays

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International Journal of Automation and computing 2008年第3期5卷 290-295页

作者： yan Sun bao-Tong Cui School of Communication and Control Engineering 3iangnan University Wuxi 3iangsu 214122 PI~C

A new definition of dissipativity for neural networks is presented in this paper. By constructing proper Lyapunov functionals and using some analytic techniques, sufficient conditions are given to ensure the dissipativity of neural networks with or without time-varying parametric uncertainties and the integro-differential neural networks in terms of linear matrix inequalities. Numerical examples are given to illustrate the effectiveness of the obtained results.

关键词： Neural network dissipativity Lyapunov functional

Large eddy simulation for wind field analysis based on stabilized finite element method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第4期12卷 278-290页

作者： Cheng HUANG yan bao Dai ZHOU Jin-quan XU School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200240 China

In this paper,a stabilized finite element technique,actualized by streamline upwind Petrov-Galerkin(SUPG) stabilized method and three-step finite element method(FEM),for large eddy simulation(LES) is developed to predict the wind flow with high Reynolds *** form of LES motion equation is combined with the SUPG stabilized term for the spatial finite element *** explicit three-step scheme is implemented for the temporal *** the numerical example of 2D wind flow over a square rib at Re=4.2×105,the Smagorinsky's subgrid-scale(SSGS) model,the DSGS model,and the DSGS model with Cabot near-wall model are applied,and their results are analyzed and compared with experimental ***,numerical examples of 3D wind flow around a surface-mounted cube with different Reynolds numbers are performed using DSGS model with Cabot near-wall model based on the present stabilized method to study the wind field and compared with experimental and numerical ***,vortex structures for wind flow around a surface-mounted cube are studied by present numerical *** and satisfactory results are obtained,which are consistent with most of the measurements even under coarse mesh.

关键词： Large eddy simulation(LES) Subgrid-scale model Stabilized finite element method(FEM) Unstructured grid Wind flow

Simulation study on factors influencing the entrainment behavior of liquid steel as bubbles pass through the steel/slag interface

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International Journal of Minerals,Metallurgy and Materials 2016年第5期23卷 511-519页

作者： Xiang Li yan-ping bao Min Wang Lu Lin State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

In this study, a water/silicone oil interface was used to simulate the steel/slag interface in a converter. A high-speed camera was used to record the entrainment process of droplets when air bubbles were passed through the water/silicone oil interface. Motion parameters of the bubbles and droplets were obtained using particle kinematic analysis software, and the entrainment rate of the droplets was calculated. It was found that the entrainment rate decreased from 29.5% to 0 when the viscosity of the silicone oil was increased from 60 mPa.s to 820 mPa.s in the case of bubbles with a 5 mm equivalent diameter passing through the water/silicone oil interface. The results indicate that in- creasing the viscosity of the silicone oil is conducive to reducing the entrainment rate. The entrainment rate increased from 0 to 136.3% in the case of silicone oil with a viscosity of 60 mPa.s when the equivalent diameter of the bubbles was increased from 3 mm to 7 ram. We there- fore conclude that small bubbles are also conductive to reducing the entrainment rate. The force analysis results for the water colmnn indicate that the entrainment rate of droplets is affected by the velocity of the bubble passing through the water/silicone oil interface and that the en- trainment rate decreases with the bubble velocity.

关键词： steelmaking bubbles interfaces entrainment influencing factors simulation studies

Existence of Mild Solutions for a Class of Fractional Non-autonomous Evolution Equations with Delay

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Acta Mathematicae Applicatae Sinica 2020年第4期36卷 870-878页

作者： Bo ZHU bao-yan HAN Wen-guang YU School of Mathematics and Quantitative Economics Shandong University of Finance and EconomicsJinan 250014China Common Course Teaching Department Shandong University of Art and DesignJinan 250014China School of Insurance Shandong University of Finance and EconomicsJinan 250014China

In this paper,we consider the existence and uniqueness of the mild solutions for a class of fractional non-autonomous evolution equations with delay and Caputo's fractional *** using the measure of noncompactness,β-resolvent family,fixed point theorems and Banach contraction mapping principle,we improve and generalizes some related results on this *** last,we give an example to illustrate the application of the main results of this paper.

关键词： Fractional non-autonomous evolution equations β-resolvent family Mild solution Measure of noncompactness.

＂Wheelchair slow transit＂ system-based elderly auxiliary travel mode

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Frontiers of Architectural Research 2015年第3期4卷 220-229页

作者： yan Lin Li bao Department of Architecture Southeast University Nanjing 210096 China

Based on research of the current situation and analysis result of a case study in the Nanjing region, this paper proposes a ＂whee（chair slow transit＂（WST） system-based elderly auxiliary travel mode. The system involves three fundamental composition frames, namely, support, transit components, and connection components. Each component is designed as an armrest, ground track, or vertical type to respond to actual demands. Thus, this system may be adaptable to diverse conditions. Taking Xiangpuying community as a case study, the author examined the application of the WST auxi（iary mode in particular communities. The WST system helps to increase the accessibility of existing public areas, creates a safe community traffic environment, improves municipal facilities, and strengthens universal design. The study intends to provide a reference to obtain a complete aged care design and to build a comfortable and livable aged care community environment.

关键词： The elderly Auxitiary travel mode"Wheetchair slowtransit" system

Optimization of large capacity six-strand tundish with flow channel for adapting situation of fewer strands casting

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Journal of Iron and Steel Research International 2021年第9期28卷 1114-1124页

作者： Cheng Yao Min Wang Ming-xu Pan yan-ping bao State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China Daye Special Steel Co. Ltd.Huangshi435000HubeiChina

Closing a single nozzle or multiple nozzles for a temporary casting operation(fewer strands casting)was common in a tundish due to insufficient molten steel or equipment ***,nozzle clogging usually happens under the situation of fewer strands ***,a temperature deviation index was introduced to characterize the temperature stratification of molten steel for a large capacity tundish,and a new calculation method of residence time curve was used to describe the different flow types of molten steel at each *** on hydraulics experiment and numerical simulation,important parameters of present case and modified case were *** the situation of fewer strands casting,the proportion of internal-recycle flow after modification decreased from 30.68%to 24.55%;the standard deviation of the response time reduced from 27.59 to 13.16,and the interquartile range of temperature deviation index changed from 0.89 to 0.27.

关键词： Large capacity tundish Fewer strands casting Internal-recycle flow Strands consistency Temperature deviation index