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Variable slip window technology in transition detection on pitching airfoil

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Chinese Journal of Aeronautics 2020年第4期33卷 1166-1180页

作者： Binbin WEI yongwei GAO dong LI Lei DENG School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China

In the pitching motion,the unsteady transition and relaminarization position plays an important role in the dynamic characteristics of the airfoil.In order to facilitate the computer to automatically and accurately calculate the position of the transition and relaminarization,a Variable Slip Window Technology(VSWT)suitable for airfoil dynamic data processing was developed using the S809 airfoil experimental data in this paper and two calculation strategies,i.e.,global strategy and single point strategy,were proposed:global strategy and single point strategy.The core of the VSWT is the selection of the window function h and the parameters setting in the h function.The effect of the VSWT was evaluated using the dimensionless pulse strength value(INB),which can be used to evaluate the signal characteristics,of the root mean square(RMS)value of the fluctuating pressure.It is found that:the h function characteristics have a significant influence on the VSWT.The suitable functions are Hn function constructed in this paper and step function.For the left boundary of the magnified area,the step function can obtain the largest INB value,but the robustness is not good.The H1 function(Gaussian-like function,n=1)can show higher robustness while ensuring a large INB value.The two computing strategies,which are single point strategy and global strategy,have their own advantages and disadvantages.The former strategy,that is the single point strategy,can achieve a higher INB value,but the RMS magnification at the feature position needs to be known in advance.Although the INB value obtained by the latter strategy,that is the global strategy,is slightly smaller than the calculation results of the former strategy,it is not necessary to know the RMS magnification at the feature position in advance.So the global strategy has better robustness.The experimental data of NACA0012 airfoil was used to further validate the developed VSWT in this paper,and the results show that the VSWT developed in this paper can still double the INB value o

关键词： Data processing Dynamic characteristics Pitching airfoil Transition and relaminarization Variable slip window technology(VSWT)

Study on temperature response of the HERD calorimeter cell

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辐射探测技术与方法(英文) 2023年第2期7卷 227-233页

作者： Yingying Dai Xingzhu Cui Xin Liu YongWei Dong Hongwei Liang Zhenzhong Zhang Xiaochuan Xia Zhipeng Wei State Key Laboratory of High Power Semiconductor Lasers Changchun University of Science and TechnologyChangchun130022China Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing100049China School of Microelectronics Dalian University of TechnologyDalian116024China

Purpose To derive the temperature response of the basic unit of the electromagnetic calorimeter of the high energy cosmic-radiation detection(HERD)facility.Method Tested a method to measure HERD calorimeter cell(HCC)light yield using an ultraviolet Light-Emitting Diode with a wavelength of 300 nm,and established an experimental setup and tested the light yield of the HCC at different temperatures in a thermal chamber.Results and conclusions The result showed that the signal amplitudes variation of the HCC reached up to 10.2% with temperature ranging from 0 to 60℃,if we narrow the temperature range to 0-35℃,the variation was about 3.7% and it showed much better linearity.This result provides a good instruction on the thermal control of the HERD calorimeter(CALO)to improve its performance.

关键词： HERD LYSO WLSF Optical output Temperature response

RMB Appreciation, Output Growth, and Inflation

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Economic and Political Studies 2013年第2期1卷 3-17页

作者： yongwei CHEN dong LI Department of Mathematics and Quantitative Economics Zhongnan University of Economics and Law the Department of Economics Kansas State University and Department of Mathematics and Quantitative Economics Zhongnan University of Economics and Law

Following Dibooglu and Kutan(2005),we construct a structural VAR model to investigate the impact of RMB(the Chinese currency)appreciation on growth and inflation in China.The empirical results show that RMB appreciation has negative effects on output growth and inflation while neither effect is statistically significant.However,exchange rate shocks are important in the fluctuations of output growth and inflation.We also simulate the scenario of a sharp currency appreciation compared to the gradual approach adopted by the Chinese government.In the counterfactual analysis we find that a sharp appreciation would lead to more violent shocks in economic growth and inflation compared to the gradual approach.

关键词： growth inflation RMB structural VAR

Nitrification performance of nitrifying bacteria immobilized in waterborne polyurethane at low ammonia nitrogen concentrations

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Journal of Environmental Sciences 2011年第3期23卷 366-371页

作者： Yamei dong Zhenjia Zhang yongwei Jin Zhirong Li Jian Lu School of Environmental Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China School of Civil and Environmental Engineering Georgia Institute of Technology Atlanta GA 30332 USA

Suspended and waterborne polyurethane immobilized nitrifying bacteria have been adopted for evaluating the effects of environmental changes, such as temperature, dissolved oxygen （DO） concentration and pH, on nitrification characteristics under conditions of low ammonia concentrations. The results showed that nitrification was prone to complete with increasing pH, DO and temperature. Sensitivity analysis demonstrated the effects of temperature and pH on nitrification feature of suspended bacteria were slightly greater than those of immobilized nitrifying bacteria. Immobilized cells could achieve complete nitrification at low ammonia concentrations when DO was sufficient. Continuous experiments were carried out to discuss the removal of ammonia nitrogen from synthetic micropollute source water with the ammonia concentration of about 1mg/L using immobilized nitrifying bacteria pellets in an up-flow inner circulation reactor under different hydraulic retention times （HRT）. The continuous removal rate remains above 80% even under HRT 30 min. The results verified that the waterborne polyurethane immobilized nitrifying bacteria pellets had great potential applications for micro-pollution source water treatment.

关键词： nitrification characteristics waterborne polyurethane immobilized nitrifying bacteria low ammonia concentrations micro-polluted source water

An improved OFDM chirp waveform used for MIMO SAR system

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Science China(Information Sciences) 2014年第6期57卷 65-73页

作者： WANG Jie LIANG Xingdong DING ChiBiao CHEN LongYong ZHOU LiangJiang dong yongwei Science and Technology on Microwave Imaging Laboratory Institute of Electronics Chinese Academy of Sciences

Special attention has been devoted to multi-input multi-output(MIMO)synthetic aperture radar(SAR)systems in recent years.The applications of MIMO SAR systems which involve 3D imaging,highresolution wide-swath remote sensing,and multi-baseline interferometry are seriously limited to the orthogonal waveforms.Although orthogonal frequency division multiplexing(OFDM)chirp waveforms can be used for MIMO SAR systems to avoid intra-pulse interferences,there is a small frequency shift between the transmitted OFDM pulses.This vulnerable shift,which can not only affect the waveform orthogonality,but also introduce residual phase error,renders the OFDM waveforms impractical.In this paper,an improved OFDM chirp waveform which works without the mentioned shift is presented,along with the novel modulation and efficient demodulation procedures.Comparison between the improved and the conventional OFDM chirp waveforms is detailed.The influence of random noise,quantization error,and Doppler shift on the orthogonality of OFDM waveform is also investigated in this paper.Theoretical analysis and simulation results illustrate the feasibility of this waveform scheme.

关键词： multi-input multi-output(MIMO) orthogonal frequency division multiplexing(OFDM) chirp waveform synthetic aperture radar(SAR) quantization noise Doppler shift

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双积分制下汽车生产商生产决策优化

系统工程理论与实践 2018年第11期38卷 2817-2830页

作者：程永伟穆东北京交通大学经济管理学院北京100044 北京物资学院现代物流产业研究院北京101149

本文研究了燃料消耗量积分和新能源汽车积分“双积分制”下汽车生产商生产决策问题,基于持股比例和内部期权协议建立了传统能源车与新能源汽车联合决策模型,在积分不足、积分富余和积分平衡三种策略情形下求解了最优定价、产量和内部积... 详细信息

本文研究了燃料消耗量积分和新能源汽车积分“双积分制”下汽车生产商生产决策问题,基于持股比例和内部期权协议建立了传统能源车与新能源汽车联合决策模型,在积分不足、积分富余和积分平衡三种策略情形下求解了最优定价、产量和内部积分协议价,并针对市场积分价格和汽车销售量的实际波动求解了生产计划的鲁棒区间及其应急调整策略.研究结果表明:持股比例主要影响内部协议价形成,持股比例越高,内部协议价越趋近于外部市场价;初始生产计划存在多维非对称鲁棒区间,汽车生产商可通过价格响应机制实现生产计划扰动管理及积分策略切换;控制积分交易限量将改变最优生产计划及其应急调整策略.

关键词：双积分碳交易新能源汽车联合决策扰动管理

RNA interference targeting ω-secalin genes differentially affects the processing quality in a wheat T1BL·1RS translocation line

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The Crop Journal 2021年第2期9卷 456-464页

作者： Shuo Zhou Cuimian Zhang He Zhao Mengyu Lyu Fushuang dong yongwei Liu Fan Yang Haibo Wang Jianfang Chai Hebei Province Plant Genetic Engineering Center Institute of Genetics and PhysiologyHebei Academy of Agriculture and Forestry SciencesShijiazhuang 050051HebeiChina

Wheat-rye T1BL·1RS translocation lines are widely used,especially in China,but their processing quality is generally poor.An interfering expression vector targeting theω-secalin genes was constructed with the 1Bx7 seed-specific promoter.Biolistic-mediated genetic transformation of the wheat cultivar KN199 carrying the T1BL·1RS translocation generated 10 transgenic lines.Two representative transgenic lines,8-2 and 13-7,were selected for analysis.Compared with the control,the two transformants showed an up to 4.5-fold decrease in totalω-secalins and various levels of decrease inω-gliadins,γ-gliadins,and low-molecular-weight glutenins.A decrease in high molecular weight(HMW)glutenin 1Bx7 was detected only in 8-2,owing possibly to promoter methylation.Increased levels ofα-gliadins were observed in both transformants,but increased levels of HMW glutenins were observed only in 13-7.Line 13-7 showed increases in gluten index,Zeleny sedimentation value,stabilization time,and maximum resistance.Its bread volume was 849.6 mL,an 11.9%increase over that of the control.Line 8-2 showed decreases in these parameters,but its total cake-making quality score was 88,an 17.3%increase over that of the control.The study demonstrates that the same RNAi construct may produce different effects on wheat processing quality and highlights the influence of the vector promoter in RNA interference.

关键词： T1BL·1RS Quality improvement RNA interference Secalin Triticum aestivum

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跨单元调度及其车辆路径集成优化

中国机械工程 2022年第6期33卷 747-755页

作者：连永伟董钊睿刘琼华中科技大学机械科学与工程学院武汉430074 昆山市科学技术局昆山215316

为了提高跨单元调度中车辆利用率,降低运输成本和缩短完工时间,综合考虑调度方案中零件的加工顺序和异常件运输路径之间的相互影响,建立了一个以最小化最大完成时间和总成本为优化目标的跨单元调度及其车辆路径集成优化模型。提出了一... 详细信息

为了提高跨单元调度中车辆利用率,降低运输成本和缩短完工时间,综合考虑调度方案中零件的加工顺序和异常件运输路径之间的相互影响,建立了一个以最小化最大完成时间和总成本为优化目标的跨单元调度及其车辆路径集成优化模型。提出了一种包含工序编码、机器编码、单元编码、车辆编码和车辆路径编码的五段式编码方法;设计了基于分解的多目标进化算法,针对算法迭代过程中可能产生不可行解的问题,提出了一种基于二叉树的车辆路径调整方法以及车辆载荷调整方法。通过实例分析,并将集成优化结果与常见运输策略结果、车辆共享策略结果进行了对比,集成优化模型在缩短最小完工时间和降低总成本方面可获得更优的结果,从而验证了所提集成优化模型的有效性。

关键词：单元制造跨单元调度车辆路径问题基于分解的多目标进化算法

Changes of hepatic biochemical parameters and proteomics in broilers with cold-induced ascites

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Journal of Animal Science and Biotechnology 2013年第4期4卷 278-286页

作者： yongwei Wang Yuming Guo dong Ning Yunzhi Peng Hong Cai Jianzhuang Tan Ying Yang Dan Liu State Key Lab of Animal Nutrition College of Animal Science and Technology China Agricultural University

Ascites syndrome is still a problem for chicken industry in various parts of the world. Despite the intensive investigations of this syndrome for many years, its pathogenesis remains unclear. The objective of this study was to analyze the difference in hepatic proteomics between ascites and healthy broilers by two-dimensional electrophoresis （2-DE） and matrix-assisted laser desorption/ionization-time of flight mass spectrometry （MALDI-TOF-MS）. Changes of biochemical parameters of liver and blood were also determined. The results indicated that red blood cell counts （RBC）, hematocrit （HCT） and haemoglobin （HGB） of ascites broilers were significantly greater than healthy broilers. Hepatic malondialdehyde （MDA） level of ascites broilers was significantly increased, and the activity of total superoxide dismutase （T-SOD） was significantly decreased. Hepatic lactic acid （LD） level of ascitic broilers were significantly lower than healthy ones, Serum glucose and cholesterol level of ascites broilers were significantly increased, and serum globulin level was significantly decreased in ascites broilers. There was no significant difference in triglyceride （TG） and blood urea nitrogen （BUN） level. The activity of liver hexokinase （HK） and succinodehydrogenase （SDH） in ascites broilers was significantly decreased, and there was no significant difference in the activity of liver pyruvate kinase （PK） and Na＋-K＋-ATPase. The hepatic proteomics analysis showed that 18 proteins expression difference were identified between ascites and healthy broilers. These proteins were mainly involved in： 1） cytoskeleton; 2） glucose, lipids and amino acid metabolism; 3） cell secretion; 4） cell apoptosis; 5） signal transduction; 6） immune and inflammatory response; and 7） cellular redox homeostasis. Mitochondrial isoform phosphoenolpyruvate carboxykinase （M-PEPCK） mainly participates in gluconeogenesis of chicken liver. In conclusion, liver oxidative damage was significantly aggravated, but antioxidant capacity was decreased in cold-induced asci

关键词： Ascites Broilers Biochemical parameters Proteomics analysis