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| 1 | Large-scale wind turbine blade design and aerodynamic analysis显示文摘Incorporating controlled elitism and dynamic distance crowding strategies, a modified NSGA-II algorithm based on a fast and genetic non-dominated sorting algorithm is developed with the aim of obtaining a novel multi-objective optimization design algorithm for wind turbine blades. As an example, a high-performance 1.5 MW wind turbine blade, taking maximum annual energy production and minimum blade mass as the optimization objectives, was designed. A 1/16-scale model of this blade was tested in a 12 m × 16 m wind tunnel and the experimental results validated the high performance. Moreover, both the computational fluid dynamics (CFD) method and a free-vortex method (FVM) were applied to calculating the aerodynamic performance, which was consistent with the experimental data. For completeness, the CFD and FVM were used to analyze the wake structure, and good and consistent results were obtained between them. | WANG TongGuang WANG Long ZHONG Wei XU BoFeng CHEN Li | 2012 | Chinese Science Bulletin2012，57，5： | 23 |
| 2 | Assessment of stochastic models for GPS measurements with different types of receivers显示文摘The stochastic model plays an important role in parameter estimation. The optimal estimator in the sense of least squares can only be obtained by using the correct stochastic model and consequently guarantees the precise positioning in GPS applications. In this contribution, the GPS measurements, collected by different types of geodetic dual-frequency receiver pairs on ultra-short baselines with a sampling interval of 1 s, are used to address their stochastic models, which include the variances of all observation types, the relationship between the observation accuracy and its elevation angle, the time correlation, as well as the correlation between observation types. The results show that the commonly used stochastic model with the assumption that all the raw GPS measurements are independent with the same variance does not meet the need for precise positioning and the elevation-dependent weight model cannot work well for different receiver and observation types. The time correlation and cross correlation are significant as well. It is therefore concluded that the stochastic model is much associated with the receiver and observation types and should be specified for the receiver and observation types. | LI BoFeng SHEN YunZhong XU PeiLiang | 2008 | Chinese Science Bulletin2008，53，20： | 21 |
| 3 | The seamless model for three-dimensional datum transformation显示文摘With extensive applications of space geodesy, three-dimensional datum transformation model has been necessarily used to transform the coordinates in the different coordinate systems.Its essence is to predict the coordinates of non-common points in the second coordinate system based on their coordinates in the first coordinate system and the coordinates of common points in two coordinate systems.Traditionally, the computation of seven transformation parameters and the transformation of noncommon points are individually implemented, in which the errors of coordinates are taken into account only in the second system although the coordinates in both two systems are inevitably contaminated by the random errors.Moreover, the coordinate errors of non-common points are disregarded when they are transformed using the solved transformation parameters.Here we propose the seamless (rigorous) datum transformation model to compute the transformation parameters and transform the non-common points integratively, considering the errors of all coordinates in both coordinate systems.As a result, a nonlinear coordinate transformation model is formulated.Based on the Gauss-Newton algorithm and the numerical characteristics of transformation parameters, two linear versions of the established nonlinear model are individually derived.Then the least-squares collocation (prediction) method is employed to trivially solve these linear models.Finally, the simulation experiment is carried out to demonstrate the performance and benefits of the presented method.The results show that the presented method can significantly improve the precision of the coordinate transformation, especially when the non-common points are strongly correlated with the common points used to compute the transformation parameters. | LI BoFeng SHEN YunZhong LI WeiXiao | 2012 | Science China Earth Sciences2012，55，12： | 19 |
| 4 | “Three essential elements”of the primary health care system:A comparison between California in the US and Guangdong in China显示文摘The primary health care system(PHCS)is the portal and basis for the national health delivery system.There are a number of elements which comprise the PHCS,but the system cannot be established and developed without the support of“three essential elements,”including general practitioners(GPs),health insurance,and government health investment.Through comparative analysis of the“three essential elements”of the PHCS between California in the US and Guangdong in China,this article indicates that there are three important aspects in developing a PHCS in China,as follows:training qualified GPs;establishing a diversified health insurance system to strengthen the policy connections between health insurance and the PHCS thereby increasing government health investment;and broadening health financing channels. | Minfang Huang Donghai Wei Louis Rubino Lianshen Wang Dazhuang Li Bofeng Ding Gan Li | 2015 | Family Medicine and Community Health2015，3，1： | 5 |
| 5 | Improved precise positioning with BDS-3 quad-frequency signals显示文摘The establishment of the BeiDou global navigation satellite system(BDS-3)has been completed,and the current constellation can independently provide positioning service globally.BDS-3 satellites provide quad-frequency signals,which can benefit the ambiguity resolution(AR)and high-precision positioning.This paper discusses the benefits of quad-frequency observations,including the precision gain of multi-frequency high-precision positioning and the sophisticated choice of extra-wide-lane(EWL)or wide-lane(WL)combinations for instantaneous EWL/WL AR.Additionally,the performance of EWL real-time kinematic(ERTK)positioning that only uses EWL/WL combinations is investigated.The results indicate that the horizontal positioning errors of ERTK positioning using ionosphere-free(IF)EWL observations are approximately 0.5 m for the baseline of 27 km and 1 m for the baseline of 300 km.Furthermore,the positioning errors are reduced to the centimetre level if the IF EWL observations are smoothed by narrow-lane observations for a short period. | Bofeng Li Zhiteng Zhang Weikai Miao Guang’e Chen | 2020 | Satellite Navigation2020，1，1： | 4 |
| 6 | LEO Enhanced Global Navigation Satellite System(LeGNSS):progress,opportunities,and challenges显示文摘With the completion of Chinese BeiDou Navigation Satellite System(BDS),the world has begun to enjoy the Positioning,Navigation,and Timing(PNT)services of four Global Navigation Satellite Systems(GNSS).In order to improve the GNSS performance and expand its applications,Low Earth Orbit(LEO)Enhanced Global Navigation Satellite System(LeGNSS)is being vigorously advocated.Combined with high-,medium-,and low-earth orbit satellites,it can improve GNSS performance in terms of orbit determination,Precise Point Positioning(PPP)convergence time,etc.This paper comprehensively reviews the current status of LeGNSS,focusing on analyzing its advantages and challenges for precise orbit and clock determination,PPP convergence,earth rotation parameter estimation,and global ionosphere modeling.Thanks to the fast geometric change brought by LEO satellites,LeGNSS is expected to fundamentally solve the problem of the long convergence time of PPP without any augmentation.The convergence time can be shortened within 1 minute if appropriate LEO constellations are deployed.However,there are still some issues to overcome,such as the optimization of LEO constellation as well as the real time LEO precise orbit and clock determination. | Haibo Ge Bofeng Li Song Jia Liangwei Nie Tianhao Wu Zhe Yang Jingzhe Shang Yanning Zheng Maorong Ge | 2022 | Geo-Spatial Information Science2022，25，1： | 4 |
| 7 | Several Kinematic Data Processing Methods for Time-Correlated Observations显示文摘Time correlations always exist in modern geodetic data,and ignoring these time correlations will affect the precision and reliability of solutions.In this paper,several methods for processing kinematic time-correlated observations are studied.Firstly,the method for processing the time-correlated observations is expanded and unified.Based on the theory of maximum a posteriori estimation,the third idea is proposed after the decorrelation transformation and differential transformation.Two types of situations with and without common parameters are both investigated by using the decorrelation transformation,differential transformation and maximum a posteriori estimation solutions.Besides,the characteristics and equivalence of above three methods are studied.Secondly,in order to balance the computational efficiency in real applications and meantime effectively capture the time correlations,the corresponding reduced forms based on the autocorrelation function are deduced.Finally,with GPS real data,the correctness and practicability of derived formulae are evaluated. | Bofeng LI Zhetao ZHANG | 2019 | Journal of Geodesy and Geoinformation Science2019，2，4： | 4 |
| 8 | Comparison and analysis of unmodelled errors in GPS and BeiDou signals显示文摘In Global Navigation Satellite Systems(GNSS) positioning,one often tries to establish a mathematic model to capture the systematic behaviors of observations as much as possible.However,the observation residuals still exhibit,to a great extent,as(somewhat systematic) signals.Nevertheless,those systematic variations are referred to as the unmodelled errors,which are difficult to be further modelled by setting up additional parameters.Different from the random errors,the unmodelled errors are colored and time correlated.In general,the larger the time correlations are,the more significant the unmodelled errors.Hence,understanding the time correlations of unmodelled errors is important to develop the theory for processing the unmodelled errors.In this study,we compare and analyze the time correlations caused by unmodelled errors of Global Positioning System(GPS) and BeiDou signals.The time correlations are estimated based on the residuals of double differenced observations on 11 baselines with different lengths.The results show that the time correlation patterns are different significantly between GPS and BeiDou observations.Besides,the code and phase data from the same satellite system are also not the same.Furthermore,the unmodelled errors are affected by not only the baseline length,but also some other factors.In addition,to make use of the time correlations with more efficiency,we propose to fit the time correlations by using exponent and quadratic models and the fitting coefficients are given.Finally,the sequential adjustment method considering the time correlations is implemented to compute the baseline solutions.The results show that the solutions considering the time correlations can objectively reflect the actual precisions of parameter estimates. | Zhetao Zhang Bofeng Li Yunzhong Shen | 2017 | Geodesy and Geodynamics2017，8，1： | 3 |
| 9 | Generation and characterization of stable pig pregastrulation epiblast stem cell lines显示文摘Pig epiblast-derived pluripotent stem cells are considered to have great potential and broad prospects for human therapeutic model developme nt and livestock breeding.Despite on going attempts since the 1990s,no stably defined pig epiblast-derived stem cell line has bee n established.Here,guided by in sights from a large-scale sin gle-cell tran scriptome an alysis of pig embryos from embryonic day(E)0 to E14,specifically,the tracing of pluripotency changes during epiblast development,we developed an in vitro culture medium for establishing and maintaining stable pluripotent stem cell lines from pig E10 pregastrulation epiblasts(pgEpiSCs).Enabled by chemical inhibition of WNT-related signaling in combination with growth factors in the FGF/ERK,JAK/STAT3,and Activin/Nodal pathways,pgEpiSCs maintain their pluripotency transcriptome features,similar to those of E10 epiblast cells,and normal karyotypes after more than 240 passages and have the potential to differentiate into three germ layers.Strikingly,ultradeep in situ Hi-C analysis revealed functional impacts of chromatin 3D-spatial associations on the transcriptional regulation of pluripote ncy marker genes in pgEpiSCs.I n practice,we con firmed that pgEpiSCs readily tolerate at least three rounds of successive gene editi ng and gene rated cloned gen e-edited live piglets.Our findings deliver on the long-a nticipated promise of pig pluripote nt stem cells and open new avenues for biological research,animal husbandry,and regenerative biomedicine. | Minglei Zhi Jinying Zhang Qianzi Tang Dawei Yu Shuai Gao Dengfeng Gao Pengliang Liu Jianxiong Guo Tang Hai Jie Gao Suying Cao Zimo Zhao Chongyang Li Xiaogang Weng Mengnan He Tianzhi Chen Yingjie Wang Keren Long Deling Jiao Guanglei Li Jiaman Zhang Yan Liu Yu Lin Daxin Pang Qianqian Zhu Naixin Chen Jingjing Huang Xinze Chen Yixuan Yao Jingcang Yang Zicong Xie Xianya Huang Mengxin Liu Ran Zhang Qiuyan Li Yiliang Miao Jianhui Tian Xingxu Huang Hongsheng Ouyang Bofeng Liu Wei Xie Qi Zhou Zhonghua Liu Caihong Zheng Mingzhou Li Jianyong Han | 2022 | Cell Research2022，32，4： | 3 |
| 10 | Semiempirical equations of state of H_(2)O/CO_(2) binary mixtures in graphite nanoslits显示文摘The existence of confining walls limits the prediction accuracy of nanoconfined fluids using macroscopic equations of state(EOSs);moreover,appropriate EOSs for multicomponent mixture fluids in nanoconfined spaces are missing.Here,we derive the EOS of multicomponent mixture fluids confined in nanospaces at high temperatures and pressures,mainly considering the nanoconfinement effect and the competitive adsorption effect between different components.Then,the EOSs are validated through comparison with the molecular dynamics-simulated Pv T data of CO_(2)/H_(2)O mixtures in graphite nanoslits.To consider the above effects,we derive two EOSs via two modeling methods:EOS I is obtained through modification of the actual component occupation volume in the Peng-Robinson equation of state(PR EOS)by fitting the binary component interaction coefficient and the number of adsorbed molecules according to a selectivity coefficient,while EOS II is obtained by considering the decreased pressure of the fluids in PR EOS by adding an attractive term between components and walls.With the simulation results as a benchmark,the two EOSs exhibited good prediction accuracies under low CO_(2) concentrations,and generally,EOS II was more accurate than EOS I.This study fills the gap in the EOSs of nanoconfined mixture fluids,and the obtained equations can help to further describe the thermodynamic properties of confined mixture fluids. | Haoxuan Li Bin Zhao Chengzhen Sun Bofeng Bai | 2023 | Science China(Physics,Mechanics & Astronomy)2023，66，8： | 2 |
| 11 | Comprehensive assessment of real-time precise products from IGS analysis centers显示文摘Real-Time Precise Point Positioning(RT-PPP)has been one of the research hotspots in GNSS(Global Navigation Satellite System)community for decades.Real-time precise products of satellite orbits and clocks are the prerequisite for RT-PPP.Thus,it is of great importance to investigate the current multi-GNSS real-time precise products in State Space Representation(SSR)from diferent analysis centers.In this article,SSR products from 10 analysis centers are comprehensively evaluated by comparing them with the fnal products and performing the kinematic PPP.The results show that analysis centers CNES(Centre National D’Etudes Spatiales)and WHU(GNSS Research Center of Wuhan University)provide the most complete products with the best quality.Concerning the accuracy of real-time products for the GNSSs,the accuracies of orbit and clock products are better than 5 cm and 0.15 ns,respectively,for Global Positioning System(GPS),followed by Galileo navigation satellite system(Galileo),BeiDou-3 Navigation Satellite System(BDS-3),GLObal NAvigation Satellite System(GLONASS),and BeiDou-2 Navigation Satellite System(BDS-2).Meanwhile,the results of the RT-PPP with quad-system show that the positioning accuracies are 1.76,1.12 and 2.68 cm in east,north,and up directions,respectively,and the convergence time to 0.1,0.1,0.2 m for corresponding directions is 15.35 min. | Bofeng Li Haibo Ge Yuhang Bu Yanning Zheng Leitong Yuan | 2022 | Satellite Navigation2022，3，1： | 2 |
| 12 | Direct synthesis of hydrogen peroxide over Pd nanoparticles embedded between HZSM-5 nanosheets layers显示文摘Direct synthesis of hydrogen peroxide(DSHP)was studied over Pd loaded on HZSM-5 nanosheets(Pd/ZN).Pd nanoparticles with average size of ca.4.3 nm were introduced into the adjacent nanosheet layers(thickness of ca.2.9 nm)by impregnation method.Pd/ZN with theoretical Si/Al molar ratio of 25 showed the highest selectivity for H2O2 among the prepared catalysts,together with highest formation rate of H2O2(38.0 mmol·(g cat)^-1·h^-1),1.9 times than that of Pd supported on conventional HZSM-5 zeolite(Pd/CZ-50).Better catalytic performance of nanosheet catalysts was attributed to the promoted Pd dispersion which promoted H2 dissociation,more BrΦnsted acid sites and stronger metal-support interaction which inhibited the dissociation of O-O bond in H2O2.The embedded structure sufficiently protected the Pd nanoparticles by space confinement which restrained the Pd leaching,leading to a better catalytic stability with 90%activity retained after 3 cycles,which was almost 3 times than that of Pd/CZ-50(30.4%activity retained). | Guozhu Liu Hairui Liang Yajie Tian Bofeng Zhang Li Wang | 2020 | Chinese Journal of Chemical Engineering2020，28，10： | 2 |
| 13 | SPM-IS: An auto-algorithm to acquire a mature soybean phenotype based on instance segmentation显示文摘Mature soybean phenotyping is an important process in soybean breeding;however, the manual process is time-consuming and labor-intensive. Therefore, a novel approach that is rapid, accurate and highly precise is required to obtain the phenotypic data of soybean stems, pods and seeds. In this research, we propose a mature soybean phenotype measurement algorithm called Soybean Phenotype Measure-instance Segmentation(SPM-IS). SPM-IS is based on a feature pyramid network, Principal Component Analysis(PCA) and instance segmentation. We also propose a new method that uses PCA to locate and measure the length and width of a target object via image instance segmentation. After 60,000 iterations, the maximum mean Average Precision(m AP) of the mask and box was able to reach 95.7%. The correlation coefficients R^(2) of the manual measurement and SPM-IS measurement of the pod length, pod width, stem length, complete main stem length, seed length and seed width were 0.9755, 0.9872, 0.9692, 0.9803,0.9656, and 0.9716, respectively. The correlation coefficients R^(2) of the manual counting and SPM-IS counting of pods, stems and seeds were 0.9733, 0.9872, and 0.9851, respectively. The above results show that SPM-IS is a robust measurement and counting algorithm that can reduce labor intensity, improve efficiency and speed up the soybean breeding process. | Shuai Li Zhuangzhuang Yan Yixin Guo Xiaoyan Su Yangyang Cao Bofeng Jiang Fei Yang Zhanguo Zhang Dawei Xin Qingshan Chen Rongsheng Zhu | 2022 | The Crop Journal2022，10，5： | 2 |
| 14 | Bias-corrected reg- ularized solution to inverse ill-posed models 显示文摘 | Shen Yunzhong Xu Peiliang Li Bofeng | 2012 | Journal of Geodesy2012，86，8： | 1 |
| 15 | Fast GNSS ambiguity resolution as an ill-posed problem 显示文摘 | LI Bofeng SHEN Yunzhong FENG Yanming | 2010 | Journal of Geodesy2010，84，11： | 1 |
| 16 | GNSS ambiguity resolution with controllable failure rate for long baseline network RTK 显示文摘 | LI Bofeng SHEN Yunzhong FENG Yanming | 2014 | Journal of Geodesy2014，88，2： | 1 |
| 17 | GNSS windowing navigation with adaptively constructed dynamic model 显示文摘 | ZHOU Zebo LI Bofeng | 2015 | GPS Solutions2015，19，： | 1 |
| 18 | Three carrier am- biguity resolution:distance-independent performance demon- strated using semi-generated triple frequency GPS signals 显示文摘 | Li Bofeng Feng Yanming Shen Yunzhong | 2010 | GPS Solution2010，14，： | 1 |
| 19 | An Iterative So- lution of Weighted Total Least-squares Adjustment显示文摘 | SHEN Yunzhong LI Bofeng CHEN Yi | 2011 | Journal of Geodesy2011，85，4： | 1 |
| 20 | A New Method for Medium and Long Range Three Frequency GNSS Rapid Ambiguity Resolution显示文摘 | Li Bofeng Shen Yunzhong | 2008 | Acta Geodaetica et Cartographica Sinica2008，37，4： | 1 |
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