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| 1 | Contribution of the Compass satellite navigation system to global PNT users显示文摘As one of the four global satellite navigation systems,Compass not only enhances satellite visibility and availability for positioning,navigation and timing (PNT) for users in China and the surrounding areas,but also improves PNT precision for global users.The improvements in satellite visibility and the dilution of precision are analyzed under GNSS compatibility and interoperation conditions.The contribution of the Compass satellite navigation system to global users,especially the benefits that users can acquire from the combination of Compass,GPS,GLONASS,and Galileo navigation systems,is analyzed using simulation data. | YANG YuanXi LI JinLong XU JunYi TANG Jing GUO HaiRong HE HaiBo | 2011 | Chinese Science Bulletin2011，56，26： | 90 |
| 2 | Preliminary assessment of the navigation and positioning performance of BeiDou regional navigation satellite system显示文摘BeiDou regional navigation satellite system(BDS)also called BeiDou-2 has been in full operation since December 27,2012.It consists of 14 satellites,including 5 satellites in Geostationary Orbit(GEO),5 satellites in Inclined Geosynchronous Orbit(IGSO),and 4 satellites in Medium Earth Orbit(MEO).In this paper,its basic navigation and positioning performance are evaluated preliminarily by the real data collected in Beijing,including satellite visibility,Position Dilution of Precision(PDOP)value,the precision of code and carrier phase measurements,the accuracy of single point positioning and differential positioning and ambiguity resolution(AR)performance,which are also compared with those of GPS.It is shown that the precision of BDS code and carrier phase measurements are about 33 cm and 2 mm,respectively,which are comparable to those of GPS,and the accuracy of BDS single point positioning has satisfied the design requirement.The real-time kinematic positioning is also feasible by BDS alone in the opening condition,since its fixed rate and reliability of single-epoch dual-frequency AR is comparable to those of GPS.The accuracy of BDS carrier phase differential positioning is better than 1 cm for a very short baseline of 4.2 m and 3 cm for a short baseline of 8.2 km,which is on the same level with that of GPS.For the combined BDS and GPS,the fixed rate and reliability of single-epoch AR and the positioning accuracy are improved significantly.The accuracy of BDS/GPS carrier phase differential positioning is about 35 and 20%better than that of GPS for two short baseline tests in this study.The accuracy of BDS code differential positioning is better than 2.5 m.However it is worse than that of GPS,which may result from large code multipath errors of BDS GEO satellite measurements. | YANG YuanXi LI JinLong WANG AiBing XU JunYi HE HaiBo GUO HaiRong SHEN JunFei DAI Xian | 2014 | Science China Earth Sciences2014，57，1： | 125 |
| 3 | Optimal dynamic excess-of-loss reinsurance and multidimensional portfolio selection显示文摘In this paper, the surplus process of the insurance company is described by a Brownian motion with drift. In addition, the insurer is allowed to invest in a risk-free asset and n risky assets and purchase excess-of-loss reinsurance. Under short-selling prohibition, we consider two optimization problems: the problem of maximizing the expected exponential utility of terminal wealth and the problem of minimizing the probability of ruin. We first show that the excess-of-loss reinsurance strategy is always better than the proportional reinsurance under two objective functions. Then, by solving the corresponding Hamilton-Jacobi-Bellman equations, the closed-form solutions of their optimal value functions and the corresponding optimal strategies are obtained. In particular, when there is no risky-free interest rate, the results indicate that the optimal strategies, under maximizing the expected exponential utility and minimizing the probability of ruin, are equivalent for some special parameter. This validates Ferguson's longstanding conjecture about the relation between the two problems. | Bai LiHua Guo JunYi | 2010 | Science China Mathematics2010，53，7： | 12 |
| 4 | Neogene eolian deposits within the West Qinling Mountains:Climatic and tectonic implications显示文摘The Qinling Mountains constitute a key climate barrier between southern and northern China.Our recent investigations revealed widely spread eolian deposits of Neogene age mantling the piedmont highlands of the intermountain basins within West Qinling.Micro-mammalian fossils dated a 150.2 m section (NL-VI) near Xihe for the late Miocene to Pliocene (~10-4 Ma).Soil micromorphology,grain-size and geochemical analysis consistently define typical loess-soil alternations for the upper (0-66 m) and lower (98-150.2 m) parts of the section,with the middle section (66-98 m) having been affected by episodic slope erosions.These results add important insights to the earlier studies about the widespread eolian deposition in northern China during the Miocene,prior to 8 Ma.They also suggest that the basic configuration of the ridges and inter-ridge basins of West Qinling has already formed by ~10 Ma.The well-preserved eolian deposits are unlikely to support intense substratum deformation and rapid uplift of West Qinling since the late Miocene. | GE JunYi 1,2 & GUO ZhengTang 3 1 State Key Laboratory of Loess and Quaternary Geology (SKLLQG),Institute of Earth Environment,Chinese Academy of Sciences,Xi’an 710075,China 2 Graduate University of Chinese Academy of Sciences,Beijing 100049,China 3 Key Laboratory of Cenozoic Geology and Environment,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China | 2010 | Chinese Science Bulletin2010，55，15： | 8 |
| 5 | Integrity analysis of COMPASS and other GNSS combined navigation显示文摘The integrity requirement should be satisfied when GNSS is used in aviation.There are now two ways for integrity monitoring,that is,receiver autonomous integrity monitoring(RAIM) and GNSS integrity channel(GIC) based on augmentation system.The rapid development of the Beidou satellite navigation system(COMPASS) will significantly improve the satellite geometry.Besides,the effects of first order ionosphere delay will be mitigated by the combination of GNSS multi-frequency signals.The availability of RAIM will be enhanced,which makes it possible to provide a worldwide seamless integrity service for aviation by using RAIM.The contribution of COMPASS to the availability of RAIM is analyzed by simulation;and the integrity requirement of which aviation approaching phrase can be satisfied when using COMPASS single system and its combination with other satellite navigation system is analyzed.Moreover,the influence of user range accuracy(URA) of COMPASS on integrity performance is discussed. | XU JunYi YANG YuanXi LI JinLong HE HaiBo GUO HaiRong | 2013 | Science China Earth Sciences2013，56，9： | 8 |
| 6 | Thick Miocene eolian deposits on the Huajialing Mountains:The geomorphic evolution of the western Loess Plateau显示文摘The geomorphic evolution of northwestern China during the Cenozoic has been a subject of much geological interest because of its link with the uplift of the Himalayan-Tibetan complex.Much information about these changes is recoverable from the sedimentary sequences of the region.We report here on the thick eolian deposits mantling the Huajialing Mountains,a relatively flat mountain range in the western Loess Plateau.Correlation of magnetic susceptibility stratigraphy with the QA-I Miocene eolian sequence dates a 134.7 m section(NL-VII) for the interval from 18.7 to 11.8 Ma,as confirmed by micro-mammalian fossils.These eolian deposits demonstrate a much wider distribution of the Miocene eolian deposits,and also indicate that the topography contrasts in the western Loess Plateau,including the uplifts of the Huajialing Mountains and the bedrock highlands in the Qinan region,were formed by the early Miocene.The near-continuous Miocene eolian sequence from 18.7 to 11.8 Ma indicates that the substratum of Huajialing had not experienced any intense tectonic changes during this time interval,which suggests further,the relative tectonic stability of the nearby Tibetan Plateau. | ZHAN Tao GUO ZhengTang WU HaiBin GE JunYi ZHOU Xin WU ChunLin ZENG FangMing | 2011 | Science China Earth Sciences2011，54，2： | 7 |
| 7 | Massive cranium from Harbin in northeastern China establishes a new Middle Pleistocene human lineage显示文摘It has recently become clear that several human lineages coexisted with Homo sapiens during the late Middle and Late Pleistocene.Here,we report an archaic human fossil that throws new light on debates concerning the diversification of the Homo genus and the origin of H.sapiens.The fossil was recovered in Harbin city in northeastern China,with a minimum uranium-series age of 146 ka.This cranium is one of the best preserved Middle Pleistocene human fossils.Its massive size,with a large cranial capacity(1,420 mL)falling in the range of modern humans,is combined with a mosaic of primitive and derived characters.It differs from all the other named Homo species by presenting a combination of features,such as long and low cranial vault,a wide and low face,large and almost square orbits,gently curved but massively developed supraorbital torus,flat and low cheekbones with a shallow canine fossa,and a shallow palate with thick alveolar bone supporting very large molars.The excellent preservation of the Harbin cranium advances our understanding of several less-complete late Middle Pleistocene fossils from China,which have been interpreted as local evolutionary intermediates between the earlier species Homo erectus and later H.sapiens.Phylogenetic analyses based on parsimony criteria and Bayesian tip-dating suggest that the Harbin cranium and some other Middle Pleistocene human fossils from China,such as those from Dali and Xiahe,form a third East Asian lineage,which is a part of the sister group of the H.sapiens lineage.Our analyses of such morphologically distinctive archaic human lineages from Asia,Europe,and Africa suggest that the diversification of the Homo genus may have had a much deeper timescale than previously presumed.Sympatric isolation of small populations combined with stochastic long-distance dispersals is the best fitting biogeographical model for interpreting the evolution of the Homo genus. | Xijun Ni Qiang Ji Wensheng Wu Qingfeng Shao Yannan Ji Chi Zhang Lei Liang Junyi Ge Zhen Guo Jinhua Li Qiang Li Rainer Grun Chris Stringer | 2021 | The Innovation2021，2，3： | 6 |
| 8 | A genome-wide analysis of SWEET gene family in cotton and their expressions under different stresses显示文摘Background: The SWEET(Sugars will eventually be exported transporters) gene family plays multiple roles in plant physiological activities and development process. It participates in reproductive development and in the process of sugar transport and absorption, plant senescence and stress responses and plant-pathogen interaction. However,thecomprehensive analysis of SWEET genes has not been reported in cotton.Results: In this study, we identified 22, 31, 55 and 60 SWEET genes from the sequenced genomes of Gossypium arboreum, G. raimondii, G. hirsutum and G. barbadense, respectively. Phylogenetic tree analysis showed that the SWEET genes could be divided into four groups, which were further classified into 14 sub-clades. Further analysis of chromosomal location, synteny analysis and gene duplication suggested that the orthologs showed a good collinearity and segmental duplication events played a crucial role in the expansion of the family in cotton. Specific MtN3_slv domains were highly conserved between Arobidopsis and cotton by exon-intron organization and motif analysis. In addition, the expression pattern in different tissues indicated that the duplicated genes in cotton might have acquired new functions as a result of sub-functionalization or neo-funtionalization. The expression pattern of SWEET genes showed that the different genes were induced by diverse stresses. The identification and functional analysis of SWEET genes in cotton may provide more candidate genes for genetic modification.Conclusion: SWEET genes were classified into four clades in cotton. The expression patterns suggested that the duplicated genes might have experienced a functional divergence. This work provides insights into the evolution of SWEET genes and more candidates for specific genetic modification, which will be useful in future research. | ZHAO Lanjie YAO Jinbo CHEN Wei LI Yan L Youjun GUO Yan WANG Junyi YUAN Li LIU Ziyang ZHANG Yongshan | 2018 | Journal of Cotton Research2018，1，2： | 6 |
| 9 | Expression of ipt gene driven by tomato fruit specific promoter and its effects on fruit development of tomato显示文摘Fruit specific promoter (2A12) from Lycopersi-com esculentum and cDNA of isopentenyl-transferase (ipt) from Ti plasmid of Agrobacterium tumerfaciens C58 were cloned by PCR procedure respectively. Two plant expression vectors with 2A12/gus or 2A12/ipt were respectively constructed. These two chimeric genes were transferred into tomato by Agrobacterium mediated procedure. The results of Southern hybridization showed that the fusion genes had been integrated into tomatoes. The result of gus histochemi-cal staining showed that 2A12 had high fruit specific expressive capability in transgenic tomato. The ipt expression resulted in accumulation of high level of cytokinins (CTKs) in fruit lead to developmental changes in fruits and seeds. The fruit of ipt transformed tomato had the hyperplastic placenta with very few seeds or even seedless. The shelf life of transgenic fruits elongated for 1-2 weeks. The ratio of fruit set, the dry weight of fruit and the crude protein content in fruit were increased, while | Zichao Mao Qiuju Yu Wei Zhen Junyi Guo Yuanlei Hu Yin Gao Zhongping Lin | 2002 | Chinese Science Bulletin2002，47，11： | 6 |
| 10 | The use of fire at Zhoukoudian:evidence from magnetic susceptibility and color measurements显示文摘In order to provide direct evidence for the use of fire by humans at Locality 1,Zhoukoudian,we examine the burnt and unburnt sediments of newly excavated area in Layer 4 by detailed measurements of magnetic susceptibility,color,and diffuse reflectance spectrum.Results show that the magnetic susceptibility and redness of the burnt sediments are remarkably higher than those of other areas on the same level:up to*22 times for magnetic susceptibility and*3 times for redness of those of the adjacent unburnt sediments.Fine-grained(superparamagnetic/stable single-domain)magnetite and hematite grains make dominant contributions to the distinctly high values of magnetic susceptibility and redness in the burnt sediments.Diffuse reflectance spectroscopy results show that the burnt sediments contain more hematite than those of other areas and localities 2 and 3.High-temperature magnetic susceptibility measurements demonstrate that the burnt sediments have been heated above 700°C.Those changes in low-frequency magnetic susceptibility and redness are impossibly resulted from natural fires,thus most likely signaling the human activities of controlled use of fire.However,further work is needed to confirm whether or not these heat-affected sediments were produced in situ. | Yan Zhang Zhengtang Guo Chenglong Deng Shuangquan Zhang Haibin Wu Chunxia Zhang Junyi Ge Deai Zhao Qin Li Yang Song Rixiang Zhu | 2014 | Chinese Science Bulletin2014，59，10： | 6 |
| 11 | Rapid Assessment on Potential Risks of Schistosomiasis Transmission—7 PLADs,China,2019 and 2021显示文摘Summary What is already known about this topic?Oncomelania hupensis(O.hupensis)and livestock are main infection sources of schistosomiasis.The schistosome infected O.hupensis and livestock’s feces are important risk factors in the transmission of schistosomiasis.What is added by this report?The potential risks of schistosomiasis transmission remain prevalent,giving an early warning to local government with information on existing transmission risks.It is expected that the effectiveness and efficiency of schistosomiasis surveillance could be improved by conducting rapid risk assessment at the beginning of transmission season. | Junyi He Hongqing Zhu Ziping Bao Lijuan Zhang Yinlong Li Ting Feng Suying Guo Wangping Deng Can Wang Hui Dang Tiewu Jia Chao Lyu Zhiqiang Qin Chunli Cao Jing Xu Shizhu Li Xiaonong Zhou | 2021 | China CDC weekly2021，3，51： | 5 |
| 12 | An all-round AI-Chemist with a scientific mind显示文摘The realization of automated chemical experiments by robots unveiled the prelude to an artificial intelligence(AI)laboratory.Several AI-based systems or robots with specific chemical skills have been demonstrated,but conducting all-round scientific research remains challenging.Here,we present an all-round AI-Chemist equipped with scientific data intelligence that is capable of performing basic tasks generally required in chemical research.Based on a service platform,the AI-Chemist is able to automatically read the literatures from a cloud database and propose experimental plans accordingly.It can control a mobile robot in-house or online to automatically execute the complete experimental process on 14 workstations,including synthesis,characterization and performance tests.The experimental data can be simultaneously analysed by the computational brain of the AI-Chemist through machine learning and Bayesian optimization,allowing a new hypothesis for the next iteration to be proposed.The competence of the AI-Chemist has been scrutinized by three different chemical tasks.In the future,the more advanced all-round AI-Chemists equipped with scientific data intelligence may cause changes to the landscape of the chemical laboratory. | Qing Zhu Fei Zhang Yan Huang Hengyu Xiao LuYuan Zhao XuChun Zhang Tao Song XinSheng Tang Xiang Li Guo He BaoChen Chong JunYi Zhou YiHan Zhang Baicheng Zhang JiaQi Cao Man Luo Song Wang GuiLin Ye WanJun Zhang Xin Chen Shuang Cong Donglai Zhou Huirong Li Jialei Li Gang Zou WeiWei Shang Jun Jiang Yi Luo | 2022 | National Science Review2022，9，10： | 5 |
| 13 | Enhanced NO_2 gas sensing of a single-layer MoS_2 by photogating and piezo-phototronic effects显示文摘NO_2 sensors with ultrahigh sensitivity are demanded for future electronic sensing systems. However,traditional sensors are considerably limited by the relative low sensitivity, high cost and complicated process. Here, we report a simply and reliable flexible NO_2 sensor based on single-layer MoS_2. The flexible sensor exhibits high sensitivity to NO_2 gas due to ultra-large specific surface area and the nature of two-dimensional(2 D) semiconductor. When the NO_2 is 400 ppb(parts per billion), compared with the dark and strain-free conditions, the sensitivity of the single-layer sensor is enhanced to 671% with a625 nm red light-emitting diode(LED) illumination of 4 mW/cm^2 power under 0.67% tensile strain.More important, the response time is dramatically reduced to $16 s and it only needs $65 s to complete90% recovery. A theoretical model is proposed to discuss the microscopic mechanisms. We find that the remarkable sensing characteristics are the result of coupling among piezoelectricity, photoelectricity and adsorption-desorption induced charges transfer in the single-layer MoS_2 Schottky junction based device.Our work opens up the way to further enhancements in the sensitivity of gas sensor based on single-layer MoS_2 by introducing photogating and piezo-phototronic effects in mesoscopic systems. | Junmeng Guo Rongmei Wen Junyi Zhai Zhong Lin Wang | 2019 | Science Bulletin2019，64，2： | 5 |
| 14 | OPTIMAL MULTI-ASSET INVESTMENT WITH NO-SHORTING CONSTRAINT UNDER MEAN-VARIANCE CRITERION FOR AN INSURER显示文摘这份报纸在标准下面为一个保险公司考虑最佳的投资策略吝啬变化。风险过程是一个复合泊松过程,保险公司能在无风险的财产和多重危险财产投资。这份报纸获得最佳的投资政策用随机线性二次(LQ ) 与没有短控制理论限制。然后,有效策略(最佳的投资策略) 和有效边疆被一条确认定理与 Hamilton-Jacobi-Bellman (HJB ) 方程的粘性答案明确地导出。 | Junna BI Junyi GUO Lihua BAI | 2011 | Journal of Systems Science & Complexity2011，24，2： | 3 |
| 15 | Design, Synthesis and Activities of Aziridine Derivatives of N^5-Methyltetrahydrofolate Against Methionine Synthase显示文摘 | DENG Xiling GUO Ying TIAN Chao LIU Junyi WANG Xiaowei ZHANG Zhili | 2015 | Chemical Research in Chinese Universities2015，31，5： | 2 |
| 16 | Parallel implementation of w-projection wide-field imaging显示文摘w-Projection is a wide-field imaging technique that is widely used in radio synthesis arrays. Processing the wide-field big data generated by the future Square Kilometre Array(SKA) will require significant updates to current methods to significantly reduce the time consumed on data processing. Data loading and gridding are found to be two major time-consuming tasks in w-projection. In this paper, we investigate two parallel methods of accelerating w-projection processing on multiple nodes: the hybrid Message Passing Interface(MPI) and Open Multi-Processing(OpenMP) method based on multicore Central Processing Units(CPUs) and the hybrid MPI and Compute Unified Device Architecture(CUDA)method based on Graphics Processing Units(GPUs). Both methods are successfully employed and operated in various computational environments, confirming their robustness. The experimental results show that the total runtime of both MPI + OpenMP and MPI + CUDA methods is significantly shorter than that of single-thread processing. MPI + CUDA generally shows faster performance when running on multiple nodes than MPI + OpenMP, especially on large numbers of nodes. The single-precision GPU-based processing yields faster computation than the double-precision processing; while the single-and doubleprecision CPU-based processing shows consistent computational performance. The gridding time remarkably increases when the support size of the convolution kernel is larger than 8 and the image size is larger than 2,048 pixels. The present research offers useful guidance for developing SKA imaging pipelines. | Baoqiang Lao Tao An Ang Yu Wenhui Zhang Junyi Wang Quan Guo Shaoguang Guo Xiaocong Wu | 2019 | Science Bulletin2019，64，9： | 2 |
| 17 | Effect of different film color mulching on dry matter and grain yield of oil flax in dry-land显示文摘Mulching can effectively maintain soil moisture;color of mulching film affects soil water storage capacity and further promote crop growth to improve grain yield.Field experiment was conducted to study effects of different film colors on dry matter accumulation(DMA)and grain yield of oil flax.Results showed that white plastic film mulching could increase leaf area,chlorophyll content and DMA.DMA of white film mulching and micro-ridge with soil covering was 53.0%higher than that of CK,and 7.8%higher than that of black film mulching.Mulching method also influenced DMA.Micro-ridge alone increased it by 13.7%than flat cultivation and soil covering improved another 7.6%under white film mulching.Both white and black film mulching with microridge could significantly improve grain yield.Black film mulching with micro-ridge and soil covering,white film mulching with micro-ridge and no soil covering significantly increased capsule number per plant,1,000-grain weight and grain yield of oil flax,compared with CK.Grain yield increased 29.0%and 28.9%respectively.These results indicated that the above mulching methods were suitable for high yield cropping pattern in dry-farming regions. | Yuhong Gao Ying Li Yingze Wang Bing Wu Jia Ke Junyi Niu Lizhuo Guo | 2020 | Oil Crop Science2020，5，2： | 2 |
| 18 | Optimal proportional reinsurance and investment with multiple risky assets and no-shorting constraint显示文摘 | Lihua Bai Junyi Guo | 2007 | Insurance Mathematics and Economics2007，，3： | 2 |
| 19 | High-performance modified uni-traveling carrier photodiode integrated on a thin-film lithium niobate platform显示文摘Lithium niobate on insulator(LNOI)has become an intriguing platform for integrated photonics for applications in communications,microwave photonics,and computing.Whereas,integrated devices including modulators,resonators,and lasers with high performance have been recently realized on the LNOI platform,high-speed photodetectors,an essential building block in photonic integrated circuits,have not been demonstrated on LNOI yet.Here,we demonstrate for the first time,heterogeneously integrated modified uni-traveling carrier photodiodes on LNOI with a record-high bandwidth of 80 GHz and a responsivity of 0.6 A/W at a 1550-nm wavelength.The photodiodes are based on an n-down In GaAs/InP epitaxial layer structure that was optimized for high carrier transit time-limited bandwidth.Photodiode integration was achieved using a scalable wafer die bonding approach that is fully compatible with the LNOI platform. | XIANGWEN GUO LINBO SHAO LINGYAN HE KEVIN LUKE JESSE MORGAN KEYE SUN JUNYI GAO TA-CHING TZU YANG SHEN DEKANG CHEN BINGTIAN GUO FENGXIN YU QIANHUAN YU MASOUD JAFARI MARKO LONčAR MIAN ZHANG ANDREAS BELING | 2022 | Photonics Research2022，10，6： | 2 |
| 20 | Local extinction of super-Brownian motion on Sierpinski gasket显示文摘 | Junyi Guo | 1998 | Science in China Series A: Mathematics1998，，3： | 1 |
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