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| 1 | Catalytic performance of Fe_3O_4-CoO/Al_2O_3 catalyst in ozonation of 2-(2,4-dichlorophenoxy) propionic acid,nitrobenzene and oxalic acid in water显示文摘Fe3O4-CoO/Al2O3 catalyst was prepared by incipient wetness impregnation using Fe(NO3) 3·9H2O and Co(NO3) 2·6H2O as the precursors,and its catalytic performance was investigated in ozonation of 2-(2,4-dichlorophenoxy) propionic acid(2,4-DP) ,nitrobenzene and oxalic acid.The experimental results indicated that Fe3O4-CoO/Al2O3 catalyst enabled an interesting improvement of ozonation eciency during the degradation of each organic pollutant,and the Fe3O4-CoO/Al2O3 catalytic ozonation system followed a radical-type mechanism.The kinetics of ozonation alone and Fe3O4-CoO/Al2O3 catalytic ozonation of three organic pollutants in aqueous solution were discussed under the mere consideration of direct ozone reaction and OH radical reaction to well investigate its performance.In the catalytic ozonation of 2,4-DP,the apparent reaction rate constants(k) were determined to be 1.456×10-2 min-1 for ozonation alone and 4.740×10-2 min-1 for O3/Fe3O4-CoO/Al2O3.And O3/Fe3O4-CoO/Al2O3 had a larger Rct(6.614×10-9) calculated by the relative method than O3 did(1.800×10-9) ,showing O3/Fe3O4-CoO/Al2O3 generated more hydroxyl radical.Similar results were also obtained in the catalytic ozonation of nitrobenzene and oxalic acid.The above results demonstrated that the catalytic performance of Fe3O4-CoO/Al2O3 in ozonation of studied organic substance was universal to a certain degree. | Shaoping Tong,Rui Shi,Hua Zhang,Chunan Ma College of Chemical Engineering and Materials Science,State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology,Zhejiang University of Technology,Hangzhou 310032,China | 2010 | Journal of Environmental Sciences2010，22，10： | 10 |
| 2 | Variable load failure mechanism for high-speed load sensing electro-hydrostatic actuator pump of aircraft显示文摘This paper presents a novel transient lubrication model for the analysis of the variable load failure mechanism of high-speed pump used in Load Sensing Electro-Hydrostatic Actuator(LS-EHA). Focusing on the slipper/swashplate pair partial abrasion, which is considered as the dominant failure mode in the high-speed condition, slipper dynamic models are established. A forth sliding motion of the slipper on the swashplate surface is presented under the fact that the slipper center of mass will rotate around the center of piston ball when the swashplate angle is dynamically adjusted. Besides, extra inertial tilting moments will be produced for the slipper based on the theorem on translation of force, which will increase rapidly when LS-EHA pump operates under highspeed condition. Then, a dynamic lubricating model coupling with fluid film thickness field, temperature field and pressure field is proposed. The deformation effects caused by thermal deflection and hydrostatic pressure are considered. A numerical simulation model is established to validate the effectiveness and accuracy of the proposed model. Finally, based on the load spectrum of aircraft flight profile, the variable load conditions and the oil film characteristics are analyzed, and series of variable load rules of oil film thickness with variable speed/variable pressure/variable displacement are concluded. | Cun SHI Shaoping WANG Xingjian WANG Yixin ZHANG | 2018 | Chinese Journal of Aeronautics2018，31，5： | 8 |
| 3 | Heat Treatment Effect on Microstructure, Hardness and Wear Resistance of Cr26 White Cast Iron显示文摘High chromium cast iron(HCCI) is taken as material of coal water slurry pump impeller, but it is susceptible to produce serious abrasive wear and erosion wear because of souring of hard coal particles. The research on optimization of heat treatments to improve abrasive wear properties of HCCI is insufficient, so effect of heat treatments on the microstructure, hardness, toughness, and wear resistance of Cr26 HCCI is investigated to determine the optimal heat treatment process for HCCI. A series of heat treatments are employed. The microstructures of HCCI specimens are examined by using optical microscopy and scanning electron microscopy. The hardness and impact fracture toughness of as-cast and heat treated specimens are measured. The wear tests are assessed by a Type M200 ring-on block wear tester. The results show the following: With increase of the quenching temperature from 950 ℃ to 1050 ℃, the hardness of Cr26 HCCI increased to a certain value, kept for a time and then decreased. The optimal heat treatment process is 2 h quenching treatment at 1000 ℃, followed by a subsequent 2 h tempering at 400 ℃. The hardness of HCCI is related to the precipitation and redissolution of secondary carbides in the process of heat treatment. The subsequent tempering treatment would result in a slight decrease of hardness but increase of toughness. The wear resistance is much related to the 'supporting' effect of the matrix and the 'protective' effect of the hard carbide embedded in the matrix, and the wear resistance is further dependent on the hardness and the toughness of the matrix. This research can provide an important insight on developing an optimized heat treatment method to improve the wear resistance of HCCI. | ZHOU Shaoping SHEN Yehui ZHANG Hao CHEN Dequan | 2015 | Chinese Journal of Mechanical Engineering2015，28，1： | 7 |
| 4 | Genome-and transcriptome-wide association studies provide insights into the genetic basis of natural variation of seed oil content in Brassica napus显示文摘Seed oil content(SOC)is a highly important and complex trait in oil crops.Here,we decipher the genetic basis of natural variation in SOC of Brassica napus by genome-and transcriptome-wide association studies using 505 inbred lines.We mapped reliable quantitative trait loci(QTLs)that control SOC in eight environments,evaluated the effect of each QTL on SOC,and analyzed selection in QTL regions during breeding.Six-hundred and ninety-two genes and four gene modules significantly associated with SOC were identified by analyzing population transcriptomes from seeds.A gene prioritization framework,POCKET(prioritizing the candidate genes by incorporating information on knowledge-based gene sets,effects of variants,genome-wide association studies,and transcriptome-wide association studies),was implemented to determine the causal genes in the QTL regions based on multi-omic datasets.A pair of homologous genes,BnPMT6s,in two QTLs were identified and experimentally demonstrated to negatively regulate SOC.This study provides rich genetic resources for improving SOC and valuable insights toward understanding the complex machinery that directs oil accumulation in the seeds of B.napus and other oil crops. | Shan Tang Hu Zhao Shaoping Lu Liangqian Yu Guofang Zhang Yuting Zhang Qing-Yong Yang Yongming Zhou Xuemin Wang Wei Ma Weibo Xie Liang Guo | 2021 | Molecular Plant2021，14，3： | 6 |
| 5 | Reliability estimation of mechanical seals based on bivariate dependence analysis and considering model uncertainty显示文摘The reliability estimation of mechanical seals is of crucial importance due to their wide applications in pumps in various mechanical systems.Failure of mechanical seals might cause leakage,and might lead to system failure and other relevant consequences.In this study,the reliability estimation for mechanical seals based on bivariate dependence analysis and considering model uncertainty is proposed.The friction torque and leakage rate are two degradation performance indicators of mechanical seals that can be described by the Wiener process,Gamma process,and inverse Gaussian process.The dependence between the two indicators can be described by different copula functions.Then the model uncertainty is considered in the reliability estimation using the Bayesian Model Average(BMA)method,while the unknown parameters in the model are estimated by Bayesian Markov Chain Monte Carlo(MCMC)method.A numerical simulation study and fatigue crack study are conducted to demonstrate the effectiveness of the BMA method to capture model uncertainty.A degradation test of mechanical seals is conducted to verify the proposed model.The optimal stochastic process models for two performance indicators and copula function are determined based on the degradation data.The results show the necessity of using the BMA method in degradation modeling. | Rentong CHEN Chao ZHANG Shaoping WANG Yujie QIAN | 2021 | Chinese Journal of Aeronautics2021，34，5： | 5 |
| 6 | Integrated genomic analysis identifies deregulated JAK/STAT-MYC-biosynthesis axis in aggressive NK-cell leukemia显示文摘好攻击的 NK 房间白血病(ANKL ) 是在从亚洲的人之中是更流行的 NK 房间瘤的一种稀罕形式并且中央并且南美洲。病人们通常在天以内死到月,甚至在收到迅速的治疗学的管理以后。这里,我们由集成整个染色体执行了 ANKL 的第一全面研究, transcriptome 并且定序指向,象功能的试金一样的 cytokine 数组。在 JAK-STAT 小径的变化在 48% 被识别(14/29 ) ANKL 病人,当细胞外的 STAT3 激发器 IL10 被 56 褶层的一般水准提高时(P < 0.0001 ) 在检查的所有病人的血浆。另外的经常变异的基因包括的 TP53 (34%) , TET2 (28%) , CREBBP (21%) 和 MLL2 (21%) 。耐心的 NK 白血病房间在多重新陈代谢的小径显示出 STAT3 phosphorylation, MYC 表示和 transcriptional 活动的突出的激活。机能上地, STAT3 激活和 MYC 表示为 ANKL 房间的增长和幸存是批评的。发信号的 STAT 调整了发信号的 MYC 抄写节目,和两 STAT, MYC 抄写被要求维持核苷酸合成和 glycolysis 的激活。一起, JAK-STAT 小径在 ANKL 为 genomic 改变和 IL10 刺激代表一个主要目标。这最新发现的 JAK/STAT-MYC-biosynthesis 轴可以在对待白血病的这种子类型为新奇治疗学的策略的发展提供机会。 | Liang Huang Dan Liu Na Wang Shaoping Ling Yuting Tang Jun Wu Lingtong Hao Hui Luo Xuelian Hu Lingshuang Sheng Lijun Zhu Di Wang Yi Luo Zhen Shang Min Xiao Xia Mao Kuangguo Zhou Lihua Cao Lili Dong Xinchang Zheng Pinpin Sui Jianlin He Shanlan Mo Jin Yan Qilin Ao Lugui Qiu Hongsheng Zhou Qifa Liu Hongyu Zhang Jianyong Li Jie Jin Li Fu Weili Zhao Jieping Chen Xin Du Guoliang Qing Hudan Liu Xin Liu Gang Huang Ding Ma Jianfeng Zhou Qian-fei Wang | 2018 | Cell Research2018，28，2： | 5 |
| 7 | Effect of pH,temperature and heating time on the formation of furan in sugar–glycine model systems显示文摘Furan(C4H4O)has been classified as a possible animal and human carcinogen by many international agencies.The formation of furan in three sugar–glycine models using glucose,fructose,and sucrose was investigated using headspace gas chromatography mass spectrometry method(HSGC–MS)with various dual combinations of three important heat processing conditions,i.e.pH,temperature,and heating time.Results indicated that furan levels from sugar–glycine model systems during the thermal processing can be attributed to selective sugar types,pH,temperature,and heating time.In glucose–glycine and fructose–glycine system,the lowest furan level was detected in acid condition but in sucrose–glycine system furan formed significantly lower(P<0.05)in acidic conditions the lowest furan level was found in alkaline conditions.The furan levels were observed to increase with heating time in all three model systems.Furthermore,less furan was generated in non-reducing sugar system(sucrose)than in reducing sugar system(glucose and fructose).Therefore,they demonstrate the possibility of limiting the formation of furan in heat processed foods by both the careful selection of carbohydrates(i.e.non-reducing sugars and reducing sugars)ingredients and appropriate processing conditions.©2013 Beijing Academy of Food Sciences.Production and hosting by Elsevier B.V.All rights reserved. | Shaoping Nie Jungen Huang Jielun Hu Yanan Zhang Sunan Wang Chang Li Massimo Marcone Mingyong Xie | 2013 | Food Science and Human Wellness2013，2，2： | 4 |
| 8 | Nonfatal Child Pedestrian Injury in Two Urban Cities of Guangdong Province,China:Results from a Cross-sectional Survey显示文摘Objective To describe the epidemiological characteristics of nonfatal child pedestrian injuries and provide information to help understand an important public-health problem.Methods This was a school-based,cross-sectional questionnaire survey.The sample (42 750 children) was obtained from two urban cities of Guangdong Province,China,using multi-stage randomized sampling.Information was collected by the respondents self-reporting in the classroom.Results The incidence rate of nonfatal child pedestrian injuries in the cities was 2.0%.Boys had a higher incidence rate (2.6%) than girls (1.4%).Compared to other children,those aged 10 years are at the highest risk.The primary places of occurrence were sidewalks,residential roads,and crosswalks.High-risk behavior of the children immediately prior to injury included mid-block crossings,playing on roads,and crossing on red lights.The major vehicles that caused pedestrian injuries were bicycles,car or vans,and motorcycles.Bruises,fractures,and injuries to the internal organs were the top three types of injuries.Almost 40% of victims were hospitalized,and nearly 30% of the victims suffered long-term disabilities.Conclusion This study shows that nonfatal child pedestrian injuries are a very serious public-health problem in the urban cities of Guangdong.Based on the epidemiological characteristics,prevention strategies and further research should be carried out to reduce the occurrence of injuries. | MA WenJun NIE ShaoPing XU HaoFeng XU YanJun XIE HuiYan ZHANG YuRun | 2011 | Biomedical and Environmental Sciences2011，24，4： | 4 |
| 9 | An accelerated life test model for harmonic drives under a segmental stress history and its parameter optimization显示文摘Harmonic drives have various distinctive advantages and are widely used in space drive mechanisms. Accelerated life test(ALT) is commonly conducted to shorten test time and reduce associated costs. An appropriate ALT model is needed to predict the lifetime of harmonic drives with ALT data. However, harmonic drives which are used in space usually work under a segmental stress history, and traditional ALT models can hardly be used in this situation. This paper proposes a dedicated ALT model for harmonic drives applied in space systems. A comprehensive ALT model is established and genetic algorithm(GA) is adopted to obtain optimal parameters in the model using the Manson fatigue damage rule to describe the fatigue failure process and a cumulative damage method to calculate and accumulate the damage caused by each segment in the stress history.An ALT of harmonic drives was carried out and experimental results show that this model is acceptable and effective. | Zhang Chao Wang Shaoping Wang Zimeng Wang Xingjian | 2015 | Chinese Journal of Aeronautics2015，28，6： | 4 |
| 10 | Discovery of Wolitu Pb-Zn deposit through geochemical prospecting under loess cover in Inner Mongolia, China显示文摘We report the finding of the Wolitu Pb-Zn deposit in Inner Mongolia, China, through a series of geochemical surveys. The Wolitu area, located in the loess-cover area in the Hure Banner, Tongliao City,Inner Mongolia, and neighboring the Horqin Sandy Land to the north, had no previous history of Pb-Zn mining or record of Pb-Zn mineralization. Our study identified a large Pb-Zn anomaly with potential zones of mineralization by stream sediment survey. Random rock sampling reveals limonitization at sporadic outcrops in the gullies. The high concentrations of Pb in the residual debris provided guidelines to fix the position for exploratory trench. Oxidized concealed orebodies were identified by trenching.Blind orebodies in veins hosted within the structural zone between slates and marbles of the upper Carboniferous Shizuizi Formation and the Permian granite were discovered by drilling. It is computed that the ore reserve may reach up to 540,000 tones with Pb grade of 1.27% and Zn of 1.9%. This case study is an excellent example for identifying potential polymetallic deposits in loess covered terrains using geochemical exploration. | Fan Yang Mu Kong Huazhong Liu Jinsong Yu Shaoping Yang Zhihong Hao Dehui Zhang Kuang Cen | 2017 | Geoscience Frontiers2017，8，5： | 3 |
| 11 | Reliability estimation of rotary lip seal in aircraft utility system based on time-varying dependence degradation model and its experimental validation显示文摘With several attractive properties, rotary lip seals are widely used in aircraft utility system, and their reliability estimation has drawn more and more attention. This work proposes a reliability estimation approach based on time-varying dependence analysis. The dependence between the two performance indicators of rotary lip seals, namely leakage rate and friction torque, is modeled by time-varying copula function with polynomial to denote the time-varying parameters, and an efficient copula selection approach is utilized to select the optimal copula function. Parameter estimation is carried out based on a Bayesian method and the reliability during the whole lifetime is calculated based on a Monte Carlo method. Degradation test for rotary lip seal is conducted and the proposed model is validated by test data. The optimal copula function and optimal order of polynomial are determined based on test data. Results show that this model is effective in estimating the reliability of rotary lip seals and can achieve a better goodness of fit. | Chao ZHANG Rentong CHEN Guanghan BAI Shaoping WANG Mileta MTOMOVIC | 2020 | Chinese Journal of Aeronautics2020，33，8： | 3 |
| 12 | Challenges and innovations in treating chronic and acute wound infections:from basic science to clinical practice显示文摘Acute and chronic wound infection has become a major worldwide healthcare burden leading to significantly high morbidity and mortality.The underlying mechanism of infections has been widely investigated by scientist,while standard wound management is routinely been used in general practice.However,strategies for the diagnosis and treatment of wound infections remain a great challenge due to the occurrence of biofilm colonization,delayed healing and drug resistance.In the present review,we summarize the common microorganisms found in acute and chronic wound infections and discuss the challenges from the aspects of clinical diagnosis,non-surgical methods and surgical methods.Moreover,we highlight emerging innovations in the development of antimicrobial peptides,phages,controlled drug delivery,wound dressing materials and herbal medicine,and find that sensitive diagnostics,combined treatment and skin microbiome regulation could be future directions in the treatment of wound infection. | Xiaotong Ding Qinghan Tang Zeyu Xu Ye Xu Hao Zhang Dongfeng Zheng Shuqin Wang Qian Tan Joanneke Maitz Peter K.Maitz Shaoping Yin Yiwei Wang Jun Chen | 2022 | Burns & Trauma2022，10，1： | 3 |
| 13 | Compact and broadband multimode waveguide bend by shape-optimizing with transformation optics显示文摘Multimode waveguide bend is one of the key components for realizing high-density mode-division multiplexing systems on chip.However,the reported multimode waveguide bends are either large,bandwidth-limited or fabrication-complicated,which hinders their applications in future high-density multimode photonic circuits.Here we propose a compact multimode waveguide bend supporting four TE modes simply by shape-optimizing with transformation optics.The shape of the waveguide is optimized in the virtual space with gradient distribution of the refractive index,so that the scattering loss and intermode cross talk are well suppressed.After conformal mapping back into the physical space,a compact(effective radius of 17μm)multimode bending waveguide is obtained.Simulations show that the proposed multimode waveguide bend has little loss(<0.1 dB)and low cross talk(<−20 dB)throughout an ultrabroad wavelength range of 1.16–1.66μm.We also fabricated the shape-optimized multimode bending waveguide on a silicon-on-insulator wafer.At 1550 nm wavelength,the measured excess losses for the four lowest-order TE modes are less than 0.6 dB,and the intermode cross talks are all below−17 dB.Our study paves the way for realizing high-density and large-scale multimode integrated optical circuits for optical interconnect. | SHUYI LI LIFENG CAI DINGSHAN GAO JIANJI DONG JIN HOU CHUNYONG YANG SHAOPING CHEN XINLIANG ZHANG | 2020 | Photonics Research2020，8，12： | 3 |
| 14 | Active fault-tolerant control strategy of large civil aircraft under elevator failures显示文摘Aircraft longitudinal control is the most important actuation system and its failures would lead to catastrophic accident of aircraft. This paper proposes an active fault-tolerant control(AFTC) strategy for civil aircraft with different numbers of faulty elevators. In order to improve the fault-tolerant flight control system performance and effective utilization of the control surface, trimmable horizontal stabilizer(THS) is considered to generate the extra pitch moment. A suitable switching mechanism with performance improvement coefficient is proposed to determine when it is worthwhile to utilize THS. Furthermore, AFTC strategy is detailed by using model following technique and the proposed THS switching mechanism. The basic fault-tolerant controller is designed to guarantee longitudinal control system stability and acceptable performance degradation under partial elevators failure. The proposed AFTC is applied to Boeing 747-200 numerical model and simulation results validate the effectiveness of the proposed AFTC approach. | Wang Xingjian Wang Shaoping Yang Zhongwei Zhang Chao | 2015 | Chinese Journal of Aeronautics2015，28，6： | 3 |
| 15 | Tectonic affinity of Paleozoic stratigraphic slices along the northern margin in Dabie Orogen,central China: evidence from Pb isotope of rocks显示文摘Metavolcanic and metasedimentary rocks from the Paleozoic tectono-stratigraphic units along the northern margin in the Dabie orogen show that there are two types of Pb isotopic compositions, which have some affined regularity with tectonic subdivision. Compared with the main tectonic units of the Qinling orogen, the Dingyuan Formation should be the part of the South Qinling orogenic belt or the northern margin of the Yangtze craton, characterized by less radiogenic Pb isotopic composition, and the Guishan Formation, Nanwan Formation-Foziling Group and the Carboniferous should be the part of the North Qinling orogenic belt which is extended to the east, characterized by more radiogenic Pb isotopic composition. These facts combined with the distribution of the geological units suggest that the Paleozoic subduction zone between the Yangtze and North China cratons should be located in the north boundary of the Nanwan Formation-Foziling Group or somewhere that is covered by the Nanwan Formation-Foziling Group now. From the Pb isotopic evidence and suggestion presented here, one aspect of the constraint is provided for determining the position of the Triassic collision suture between the two cratons. | XU Qidong, OUYANG Jianping, ZHANG Benren and KUANG Shaoping(1. Faculty of Earth Resources, China University of Geosciences, Wuhan 430074, China 2. Institute of Geochemistry, China University of Geosciences, Wuhan 430074, China) | 2002 | Progress in Natural Science:Materials International2002，12，6： | 3 |
| 16 | A multicenter retrospective cohort study of ketogenic diet therapy in 481 children with infantile spasms显示文摘Background:Ketogenic diet(KD)therapy is one of the main treatments for drug-resistant epilepsy.However,the KD therapy has been applied in only a small number of infantile spasm cases.In this large multicenter study,we investigated the efficacy of KD therapy in the treatment of infantile spasms.Methods:In this retrospective,multicenter cohort study,clinical data from main epilepsy centers were analyzed.Patients were classified into different groups according to age,type of drug and whether glucocorticoid was used before initiation of KD.Results:From October 2014 to March 2020,481 patients(308 males and 173 females)with infantile spasms were treated with the KD therapy.The age of the patients ranged from 2 months to 20 years,with a mean age of 1 year and 10 months.The number of anti-seizure medications(ASMs)used before KD initiation ranged 0-6,with a median of 3.In different time from initiation(1,3,6,and 12 months),the rates of seizure freedom after KD were 6.9,11.6;16.0 and 16.8%,respectively(x^(2)=27.1772,P<0.0001).There was a significant difference in the rate of seizure freedom between 3 months and 1 month(x^(2)=6.5498,P=0.0105)groups,and 6 months and 3 months(x^(2)=3.8478,P=0.0498)groups,but not between 12 months and 6 months(x^(2)=0.1212,P=0.7278)groups.The rates of effectiveness were 44.7;62.8,49.1 and 32.0%(x^(2)=93.2674,P<0.0001),respectively.The retention rates were 94.0,82.5,55.7 and 33.1%(x^(2)=483.7551,P<0.0001),correspondingly.The rate of effectiveness and the retention rate of KD were significantly different among the 1,3,6 and 12 months.KD treatment was the first choice in 25 patients(5.2%),55 patients(11.4%)started KD after the failure of the first ASM,158 patients(32.8%)started KD after the failure of the second ASM,157 patients(32.6%)started KD after the failure of the third drug,and 86 patients(17.9%)started KD after the failure of the fourth and more.The KD effect was not related to the number of ASMs used before KD startup(P>0.05).Two hundred and eighteen patients(45.3%)failed to respond to corticotropin or glucocorticoid before initiation.There was no significant difference in the effectiveness rate at different time points between the group of KD therapy after glucocorticoid failure and the group after non-hormone failure (x^(2)=0.8613,P=0.8348).The rate of adverse events of KD in 1,3,6,and 12 months after KD initiation were 22.3,21.7,16.8 and 6.9%,respectively.The adverse events mainly occurred during the first 3 months of KD,and the main adverse events were gastrointestinal disturbance and constipation.Conclusions:The efficacy of the KD treatment for infantile spasms was not affected by age,medication,and glucocorticoid use before initiation.KD is one of the effective treatments for infantile spasms. | Yuanzhen Ye Dan Sun Hua Li Jianmin Zhong Rong Luo Baomin Li Dengna Zhu Dan Li Shaoping Huang Yuwu Jiang Nong Xiao Yucai Chen Yuqin Zhang Mei Yu Xiaoyun Shen Li Gao Guo Zheng Congmin Zhao Baoqiang Yuan Jianxiang Liao Jiong Qin CAAE KD group | 2022 | Acta Epileptologica2022，5，1： | 2 |
| 17 | Effect of Migration on Children's Self-esteem in Rural China显示文摘China's rapid economic growth has been facilitated by its large volume of rural to urban migration.China's projected future development,especially increasing urbanization,implies that such migration will further intensify.However,migration does not come without cost.There are concerns about the potential negative impacts of migration on children 's care,education,and,in particular,the self-esteem of children left behind in villages where one or both parents have out-migrated to cities.In this paper,we employ unique survey data collected from Shaanxi Province,where more than 4700 ninth grade students from 36 rural junior high schools in five counties were surveyed in late 2011.The results show that having both parents migrate into cities significantly reduced children 's self-esteem.The effects are also gender sensitive.Girls that had a father or both parents who had out-migrated were inclined to have lower self-esteem than boys.Moreover,our study findings indicate that parental migration decreased children 's self-esteem more for individuals with initial low self-esteem. | Xuefeng Zhan Shaoping Li Chengfang Liu Linxiu Zhang | 2014 | China & World Economy2014，22，4： | 2 |
| 18 | A new adaptive Kalman filter for navigation systems of carrier-based aircraft显示文摘The features of carrier-based aircraft’s navigation systems during the approach and landing phases are investigated.A new adaptive Kalman filter with unknown state noise statistics is proposed to improve the accuracy of the INS/GNSS integrated navigation system.The adaptive filtering algorithm aims to estimate and adapt the unknown state noise covariance Q in high dynamic conditions,when the measurement noise covariance R is assumed to be known empirically in advance.The new adaptive Kalman filter based on the innovation sequence and pseudo-measurement vector approach makes it more effective to estimate and adapt Q.The simulation results and semi-physical experiments show that the application of the proposed adaptive Kalman filter can guarantee a higher estimation accuracy of the state variables. | Lifei ZHANG Shaoping WANG Maria Sergeevna SELEZNEVA Konstantin Avenirovich NEUSYPIN | 2022 | Chinese Journal of Aeronautics2022，35，1： | 2 |
| 19 | JASMIN: a parallel software infrastructure for scientific computing显示文摘 | Zeyao Mo Aiqing Zhang Xiaolin Cao Qingkai Liu Xiaowen Xu Hengbin An Wenbing Pei Shaoping Zhu | 2010 | Frontiers of Computer Science in China2010，，4： | 2 |
| 20 | Evaluation of thermal effects on temperature-sensitive operating force of flow servo valve for fuel metering unit显示文摘The temperature-induced variation in operating force of flow control valves may result in performance degradation or even jam faults of fuel metering unit(FMU), which significantly affects the safety of aircrafts. In this work, an analytical modeling approach of temperature-sensitive operating-force of servo valve is proposed to investigate the temperature characteristics in varying temperature conditions. Considering the temperature effects, a new extended model of flow force is built and an analytical model of valve friction is also derived theoretically based on the dynamic clearance induced by thermal effects. The extremum condition of friction is obtained to analyze the characteristic-temperature points where jam faults occur easily. The numerical results show that flow force increases firstly and then decreases as temperature increases under a constant valve opening. The maximum friction of flow servo valve can be uniquely determined when the structural parameters and ambient temperature are given. The worst situation just happens at the characteristic-temperature points, which are linearly related to the axial temperature gradients of valve spool. Such evaluations may give an explanation for the temperature-induced jam faults of vulnerable valves and provide a reference for designers to determine a suitable workingtemperature range of valves in practice. | Yang ZHANG Shaoping WANG Jian SHI Xi WANG | 2020 | Chinese Journal of Aeronautics2020，33，6： | 2 |
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