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| 1 | Relative Contributions of Boundary-Layer Meteorological Factors to the Explosive Growth of PM2.5 during the Red-Alert Heavy Pollution Episodes in Beijing in December 2016显示文摘Based on observations of urban mass concentration of fine particulate matter smaller than 2.5 μm in diameter(PM_(2.5)), ground meteorological data, vertical measurements of winds, temperature, and relative humidity(RH), and ECMWF reanalysis data, the major changes in the vertical structures of meteorological factors in the boundary layer(BL) during the heavy aerosol pollution episodes(HPEs) that occurred in winter 2016 in the urban Beijing area were analyzed. The HPEs are divided into two stages: the transport of pollutants under prevailing southerly winds, known as the transport stage(TS), and the PM_(2.5) explosive growth and pollution accumulation period characterized by a temperature inversion with low winds and high RH in the lower BL, known as the cumulative stage(CS). During the TS, a surface high lies south of Beijing, and pollutants are transported northwards. During the CS, a stable BL forms and is characterized by weak winds, temperature inversion, and moisture accumulation. Stable atmospheric stratification featured with light/calm winds and accumulated moisture(RH > 80%) below 250 m at the beginning of the CS is closely associated with the inversion, which is strengthened by the considerable decrease in near-surface air temperature due to the interaction between aerosols and radiation after the aerosol pollution occurs. A significant increase in the PLAM(Parameter Linking Aerosol Pollution and Meteorological Elements) index is found, which is linearly related to PM mass change. During the first 10 h of the CS, the more stable BL contributes approximately 84% of the explosive growth of PM_(2.5) mass. Additional accumulated near-surface moisture caused by the ground temperature decrease, weak turbulent diffusion, low BL height, and inhibited vertical mixing of water vapor is conducive to the secondary aerosol formation through chemical reactions, including liquid phase and heterogeneous reactions, which further increases the PM_(2.5) concentration levels. The contribution of these reaction mechanisms to the explosive growth of PM_(2.5) mass during the early CS and subsequent pollution accumulation requires further investigation. | junting zhong xiaoye zhang yaqiang wang junying sun yangmei zhang jizhi wang kaiyan tan xiaojing shen haochi che lu zhang zhouxiang zhang xuefei qi huarong zhao sanxue ren yang li | 2017 | Journal of Meteorological Research2017，31，5： | 25 |
| 2 | Seasonal characterization of components and size distributions for submicron aerosols in Beijing显示文摘Submicron aerosols(PM1)in Beijing were studied using an Aerodyne aerosol mass spectrometer(AMS)from January to October 2008.This paper presents seasonal variations of different chemical components(sulfate,nitrate,ammonium,chloride and organics)and size distributions of PM1.Results show that mass concentration of PM1 was highest in summer,and lowest in autumn.Organics represented the dominant species in all seasons,accounting for 36%-58%of PM1,and their concentrations were highest in winter.Concentrations of inorganic components,sulfate,nitrate,and ammonium were highest in summer. Based on principal component analysis,organics were deconvolved and quantified as hydrocarbon-like and oxygenated organic aerosol(HOA and OOA,respectively).HOA was highest in winter,accounting for about 70%of organics.However,OOA was highest in summer,and had lower values in autumn and winter.A similar diurnal pattern of various components was ob- served,which is higher at nighttime and lower during daytime.HOA increased more dramatically than other species between 17:00 and 21:00 and peaked at noon,which could be related to cooking emissions. OOA,sulfate,nitrate,ammonium and chloride varied with the same trend.Their concentrations increased with solar radiation from 9:00 to 13:00,and declined with weakening solar radiation.Size distributions of all species showed apparent peaks in the range 500-600 nm.Size distributions of organics were much broader than other species,particularly in autumn and winter.Distributions of sulfate,nitrate and ammonium had similar patterns,broadening in winter.Contributions of different species were size-dependent;the finer the particle,the greater the contribution of organics.Organics represented more than 60%of particles smaller than 200 nm,contributing 50%to PM1 in winter.In spring and summer,HOA was the dominant organic fraction for particles smaller than 200 nm, while OOA contributed more to particles larger than 300 nm.In winter,HOA contributed more than OOA to all PM1 particles. | ZHANG YangMei SUN JunYing ZHANG XiaoYe SHEN XiaoJing WANG TingTing QIN MingKai | 2013 | Science China Earth Sciences2013，56，5： | 14 |
| 3 | Spatial transcriptomic survey of human embryonic cerebral cortex by single-cell RNA-seq analysis显示文摘人的大脑开发的细胞的复杂性强烈地被调查了,尽管全部人的服的外皮的地区性的描述没基于单个房间的 transcriptome 分析被报导。这里,我们从人的中间怀孕期的胚胎的 22 个大脑区域在超过 4,000 个单个房间上执行了 RNA-seq。我们识别了 29 房间亚簇,它证明在每个区域和脑桥的不同比例显示出星形细胞的特别高的百分比。胚胎的神经原不象成年神经原一样多样,尽管他们在成年人拥有了他们的命运的重要特征。神经原开发是在服的外皮的 unsynchronized,当背面的区域看起来比在这个阶段的腹的区域更成熟。区域特定的基因包括地在每 neuronal 亚簇被识别,并且这些基因的一个大比例是联系的神经疾病。我们的结果介绍区域化的基因表示的一处系统的风景和人的服的外皮的神经原成熟。 | Xiaoying Fan Ji Dong Suijuan Zhong Yuan Wei Qian Wu Liying Yan Jun Yong Le Sun Xiaoye Wang Yangyu Zhao Wei Wang Jie Yan Xiaoqun Wang Jie Qiao Fuchou Tang | 2018 | Cell Research2018，28，7： | 11 |
| 4 | Aerosol Hygroscopicity during the Haze Red-Alert Period in December 2016 at a Rural Site of the North China Plain显示文摘A humidification system was deployed to measure aerosol hygroscopicity at a rural site of the North China Plain during the haze red-alert period 17–22 December 2016. The aerosol scattering coefficients under dry [relative humidity(RH) < 30%] and wet(RH in the range of 40%–85%) conditions were simultaneously measured at wavelengths of450, 550, and 700 nm. It is found that the aerosol scattering coefficient and backscattering coefficient increased by only 29% and 10%, respectively when RH went up from 40% to 80%, while the hemispheric backscatter fraction went down by 14%, implying that the aerosol hygroscopicity represented by the aerosol scattering enhancement factor f(RH) is relatively low and RH exerted little effects on the aerosol light scattering in this case. The scattering enhancement factors do not show significant differences at the three wavelengths, only with an approximate 2% variation, suggesting that the aerosol hygroscopicity is independent of the wavelength. Aerosol hygroscopicity is highly dependent on the aerosol chemical composition. When there is a large mass fraction of inorganics and a small mass fraction of organic matter, f(RH) reaches a high value. The fraction of NO_3^- was strongly correlated with the aerosol scattering coefficient at RH = 80%, which suggests that NO_3^- played an important role in aerosol hygroscopic growth during the heavy pollution period. | Xuefei QI Junying SUN Lu ZHANG Xiaojing SHEN Xiaoye ZHANG Yangmei ZHANG Yaqiang WANG Haochi CHE Zhouxiang ZHANG Junting ZHONG Kaiyan TAN Huarong ZHAO Sanxue REN | 2018 | Journal of Meteorological Research2018，32，1： | 7 |
| 5 | Key features of new particle formation events at background sites in China and their influence on cloud condensation nuclei显示文摘 | Xiaojing SHEN Junying SUN Xiaoye ZHANG Yangmei ZHANG Lu ZHANG Ruxia FAN | 2016 | Frontiers of Environmental Science & Engineering2016，10，5： | 5 |
| 6 | Chemical Components, Variation, and Source Identification of PM1 during the Heavy Air Pollution Episodes in Beijing in December 2016显示文摘Air pollution is a current global concern. The heavy air pollution episodes(HPEs) in Beijing in December 2016 severely influenced visibility and public health. This study aims to survey the chemical compositions, sources, and formation processes of the HPEs. An aerodyne quadruple aerosol mass spectrometer(Q-AMS) was utilized to measure the non-refractory PM1(NR-PM1) mass concentration and size distributions of the main chemical components including organics, sulfate, nitrate, ammonium, and chloride in situ during 15–23 December 2016. The NR-PM1 mass concentration was found to increase from 6 to 188 μg m–3 within 5 days. During the most serious polluted episode, the PM1 mass concentration was about 2.6 times that during the first pollution stage and even 40 times that of the clean days. The formation rates of PM2.5 in the five pollution stages were 26, 22, 22, 32, and 67 μg m^(–3) h–1, respectively. Organics and nitrate occupied the largest proportion in the polluted episodes, whereas organics and sulfate dominated the submicron aerosol during the clean days. The size distribution of organics is always broader than those of other species, especially in the clean episodes. The peak sizes of the interested species grew gradually during different HPEs. Aqueous reaction might be important in forming sulfate and chloride, and nitrate was formed via oxidization and condensation processes. PMF(positive matrix factorization) analysis on AMS mass spectra was employed to separate the organics into different subtypes. Two types of secondary organic aerosol with different degrees of oxidation consisted of 43% of total organics. By contrast, primary organics from cooking, coal combustion, and traffic emissions comprised 57% of the organic aerosols during the HPEs. | Yangmei ZHANG Yaqiang WANG Xiaoye ZHANG Xiaojing SHEN Junying SUN Lingyan WU Zhouxiang ZHANG Haochi CHE | 2018 | Journal of Meteorological Research2018，32，1： | 4 |
| 7 | Publishing Social Graphs with Differential Privacy Guarantees Based on wPINQ显示文摘To publish social graphs with differential privacy guarantees for reproducing valuable results of scientific researches, we study a workflow for graph synthesis and propose an improved approach based on weighted Privacy integrated query(wPINQ). The workflow starts with a seed graph to fit the noisy degree sequence, which essentially is the 1K-graph. In view of the inaccurate assortativity coefficient, we truncate the workflow to replace the seed graph with an optimal one by doing target 1K-rewiring while preserving the 1K-distribution. Subsequently, Markov chain Monte Carlo employs the new seed graph as the initial state, and proceeds step by step guided by the information of Triangles by intersect to increase the number of triangles in the synthetic graphs. The experimental results show that the proposed algorithm achieves better performance for the published social graphs. | LI Xiaoye YANG Jing SUN Zhenlong ZHANG Jianpei | 2019 | Chinese Journal of Electronics2019，28，2： | 2 |
| 8 | Optical and Radiative Properties of Aerosols during a Severe Haze Episode over the North China Plain in December 2016显示文摘The optical and radiative properties of aerosols during a severe haze episode from 15 to 22 December 2016 over Beijing, Shijiazhuang, and Jiaozuo in the North China Plain were analyzed based on the ground-based and satellite data, meteorological observations, and atmospheric environmental monitoring data. The aerosol optical depth at 500 nm was < 0.30 and increased to > 1.4 as the haze pollution developed. The ?ngstr?m exponent was > 0.80 for most of the study period. The daily single-scattering albedo was > 0.85 over all of the North China Plain on the most polluted days and was > 0.97 on some particular days. The volumes of fine and coarse mode particles during the haze event were approximately 0.05–0.21 and 0.01–0.43 μm3, respectively—that is, larger than those in the time without haze. The daily absorption aerosol optical depth was about 0.01–0.11 in Beijing, 0.01–0.13 in Shijiazhuang, and0.01–0.04 in Jiaozuo, and the average absorption ?ngstr?m exponent varied between 0.6 and 2.0. The aerosol radiative forcing at the bottom of the atmosphere varied from –23 to –227, –34 to –199, and –29 to –191 W m–2 for the whole haze period, while the aerosol radiative forcing at the top of the atmosphere varied from –4 to –98, –10 to –51,and –21 to –143 W m–2 in Beijing, Shijiazhuang, and Jiaozuo, respectively. Satellite observations showed that smoke,polluted dust, and polluted continental components of aerosols may aggravate air pollution during haze episodes. The analysis of the potential source contribution function and concentration-weighted trajectory showed that the contribution from local emissions and pollutants transport from upstream areas were 190–450 and 100–410 μg m^(–3), respectively. | Yu ZHENG Huizheng CHE Leiku YANG Jing CHEN Yaqiang WANG Xiangao XIA Hujia ZHAO Hong WANG Deying WANG Ke GUI Linchang AN Tianze SUN Jie YU Xiang KUANG Xin LI Enwei SUN Dapeng ZHAO Dongsen YANG Zengyuan GUO Tianliang ZHAO Xiaoye ZHANG | 2017 | Journal of Meteorological Research2017，31，6： | 2 |
| 9 | Robust prediction of hourly PM_(2.5) from meteorological data using LightGBM显示文摘Retrieving historical fine particulate matter(PM_(2.5))data is key for evaluating the long-term impacts of PM_(2.5) on the environment,human health and climate change.Satellite-based aerosol optical depth has been used to estimate PM_(2.5),but estimations have largely been undermined by massive missing values,low sampling frequency and weak predictive capability.Here,using a novel feature engineering approach to incorporate spatial effects from meteorological data,we developed a robust Light GBM model that predicts PM_(2.5) at an unprecedented predictive capacity on hourly(R^(2)=0.75),daily(R^(2)=0.84),monthly(R^(2)=0.88)and annual(R^(2)=0.87)timescales.By taking advantage of spatial features,our model can also construct hourly gridded networks of PM_(2.5).This capability would be further enhanced if meteorological observations from regional stations were incorporated.Our results show that this model has great potential in reconstructing historical PM_(2.5) datasets and real-time gridded networks at high spatial-temporal resolutions.The resulting datasets can be assimilated into models to produce long-term re-analysis that incorporates interactions between aerosols and physical processes. | Junting Zhong Xiaoye Zhang Ke Gui Yaqiang Wang Huizheng Che Xiaojing Shen Lei Zhang Yangmei Zhang Junying Sun Wenjie Zhang | 2021 | National Science Review2021，8，10： | 2 |
| 10 | Comparison of Submicron Particles at a Rural and an Urban Site in the North China Plain during the December 2016 Heavy Pollution Episodes显示文摘An extensive field experiment for measurement of physical and chemical properties of aerosols was conducted at an urban site in the Chinese Academy of Meteorological Sciences(CAMS) in Beijing and at a rural site in Gucheng(GC), Hebei Province in December 2016. This paper compares the number size distribution of submicron particle matter(PM1, diameter < 1 μm) between the two sites. The results show that the mean PM1 number concentration at GC was twice that at CAMS, and the mass concentration was three times the amount at CAMS. It is found that the accumulation mode(100–850 nm) particles constituted the largest fraction of PM1 at GC, which was significantly correlated with the local coal combustion, as confirmed by a significant relationship between the accumulation mode and the absorption coefficient of soot particles. The high PM1 concentration at GC prevented the occurrence of new particle formation(NPF) events, while eight such events were observed at CAMS. During the NPF events, the mass fraction of sulfate increased significantly, indicating that sulfate played an important role in NPF. The contribution of regional transport to PM1 mass concentration was approximately 50% at both sites, same as that of the local emission. However, during the red-alert period when emission control took place, the contribution of regional transport was notably higher. | Xiaojing SHEN Junying SUN Xiaoye ZHANG Yangmei ZHANG Yaqiang WANG Kaiyan TAN Peng WANG Lu ZHANG Xuefei QI Haochi CHE Zhouxiang ZHANG Junting ZHONG Huarong ZHAO Sanxue REN | 2018 | Journal of Meteorological Research2018，32，1： | 2 |
| 11 | Multi-vision Attention Networks for on-Line Red Jujube Grading显示文摘To solve the red jujube classification problem,this paper designs a convolutional neural network model with low computational cost and high classification accuracy.The architecture of the model is inspired by the multi-visual mechanism of the organism and Dense Net.To further improve our model,we add the attention mechanism of SE-Net.We also construct a dataset which contains 23,735 red jujube images captured by a jujube grading system.According to the appearance of the jujube and the characteristics of the grading system,the dataset is divided into four classes:invalid,rotten,wizened and normal.The numerical experiments show that the classification accuracy of our model reaches to 91.89%,which is comparable to Dense Net-121,Inception V3,Inception V4,and Inception-Res Net v2.Our model has real-time performance. | SUN Xiaoye MA Liyan LI Gongyan | 2019 | Chinese Journal of Electronics2019，28，6： | 2 |
| 12 | LILRB4 ITIMs mediate the T cell suppression and infiltration of acute myeloid leukemia cells显示文摘We recently demonstrated that leukocyte Ig-like receptor 4(LILRB4)expressed by monocytic acute myeloid leukemia(AML)cells mediates T-cell inhibition and leukemia cell infiltration via its intracellular domain.The cytoplasmic domain of LILRB4 contains three immunoreceptor tyrosine-based inhibitory motifs(ITIMs);the tyrosines at positions 360,412,and 442 are phosphorylation sites.Here,we analyzed how the ITIMs of LILRB4 in AML cells mediate its function.Our in vitro and in vivo data show that Y412 and Y442,but not Y360,of LILRB4 are required for T-cell inhibition,and all three ITIMs are needed for leukemia cell infiltration.We constructed chimeric proteins containing the extracellular domain of LILRB4 and the intracellular domain of LILRB1 and vice versa.The intracellular domain of LILRB4,but not that of LILRB1,mediates T-cell suppression and AML cell migration.Our studies thus defined the unique signaling roles of LILRB4 ITIMs in AML cells. | Zunling Li Mi Deng Fangfang Huang Changzhu Jin Shuang Sun Heyu Chen Xiaoye Liu Licai He Ali HSadek Cheng Cheng Zhang | 2020 | Cellular & Molecular Immunology2020，17，3： | 1 |
| 13 | Atmospheric Particle Hygroscopicity and the Influence by Oxidation State of Organic Aerosols in Urban Beijing显示文摘A hygroscopic tandem differentialmobility analyser(H-TDMA)was used to observe the sizeresolved hygroscopic characteristics of submicron particles in January and April 2018 in urban Beijing.The probability distribution of the hygroscopic growth factor(HGF-PDF)in winter and spring usually showed a bimodal pattern,with more hygroscopic mode(MH)being more dominant.The seasonal variation in particle hygroscopicity was related to the origin of air mass,which received polluted southerly air masses in spring and clean northwesterly air masses in winter.Particles showed stronger hygroscopic behaviour during heavy pollution episodes(HPEs)with elevated concentrations of secondary aerosols,especially higher mass fraction of nitrate,which were indicated using the PM2.5(particulate matter with diameter below 2.5μm)mass concentration normalised by CO mass concentration.The hygroscopic parameter(κ)values were calculated using H-TDMA(κhtdma)and chemical composition(κchem).The closure study showed thatκchem was overestimated in winter afternoon when compared withκhtdma,because the organic particle hygroscopic parameter(κorg)was overestimated in the calculations.It was influenced by the presence of a high concentration of hydrocarbon-like organic aerosol(HOA)with a weak water uptake ability.A positive relationship was observed betweenκorg and the ratio of oxygenated organic aerosol(OOA)and HOA,thereby indicating that the strong oxidation state enhanced the hygroscopicity of the particles.This study revealed the effect of local emission sources and secondary aerosol formation processes on particle hygroscopicity,which is of great significance for understanding the pollution formation mechanism in the North China Plain. | Sinan Zhang Xiaojing Shen Junying Sun Yangmei Zhang Xiaoye Zhang Can Xia Xinyao Hu Junting Zhong Jialing Wang Shuo Liu | 2023 | Journal of Environmental Sciences2023，，2： | 1 |
| 14 | Spatial and temporal distribution of the cloud optical depth over China based on MODIS satellite data during 2003–2016显示文摘The cloud optical depth(COD) is one of the important parameters used to characterize atmospheric clouds. We analyzed the seasonal variations in the COD over East Asia in 2011 using cloud mode data from the AERONET(Aerosol Robotic Network) ground-based observational network. The applicability of the MODIS(Moderate Resolution Imaging Spectroradiometer) COD product was verified and compared with the AERONET cloud mode dataset. There was a good correlation between the AERONET and the MODIS. The spatial and temporal distribution and trends in the COD over China were then analyzed using MODIS satellite data from 2003 to 2016. The seasonal changes in the AERONET data and the time sequence variation of the satellite data suggest that the seasonal variations in the COD are significant. The result shows that the COD first decreases and then increases with the season in northern China, and reaches the maximum in summer and minimum in winter.However, the spatial distribution change is just the opposite in southern China. The spatial variation trend shows the COD in China decreases first with time and gradually increases after 2014. And the trend of COD in the western and central China is consistent with that in China. While the trend of COD shows a continuously increasing over time in northeast China and the Pearl River Delta. | Xiaopan Li Huizheng Che Hong Wang Xiang'ao Xia Quanliang Chen Ke Gui Hujia Zhao Linchang An Yu Zheng Tianze Sun Zhizhong Sheng Chao Liu Xiaoye Zhang | 2019 | Journal of Environmental Sciences2019，31，6： | 1 |
| 15 | Prevalencecorrelates of HIV and syphilisinfections among man who have sex with man in seven provinces in China with historically low HIV prevalence显示文摘 | XiaoY Sun J Li C | 2010 | J Acquir Immune DeficSyndr2010，531，： | 1 |
| 16 | Highly time- and size-resolved characterization of submicron aerosol particles in Beijing using an Aerodyne Aerosol Mass Spectrometer显示文摘 | Junying Sun Qi Zhang Manjula R. Canagaratna Yangmei Zhang Nga L. Ng Yele Sun John T. Jayne Xiaochun Zhang Xiaoye Zhang Douglas R. Worsnop | 2009 | Atmospheric Environment2009，，1： | 1 |
| 17 | Development of an integrating sphere calibration method for Cimel sunphotometers in China aerosol remote sensing network显示文摘Based on the integrating sphere traced from the National Institute of Standards and Technology(NIST,USA), a sphere calibration method and protocol for the China aerosol remote sensing network(CARSNET)Cimel sun photometer was established. Four CE318 sun photometers were verified using the proposed calibration method and operational protocol. The calibration results showed that the instrument coefficients differed by less than 3% for visible(~5% for infrared) wavelengths from the original ones stated by Cimel Electronique. In situ validation experiment data showed that radiances at ±6° measured by sun collimator(aureole) were consistent with those measured by sky collimator(sky), under both almucantar(ALMUC)^nd principal plane(PPLAN) scenarios. Differences at all wavelengths were less than 1%, indicating that the method and protocol are suitable for CARSNET field sun photometer calibration, and would benefit improvement of data quality and accuracy of network observations. | Ran Tao Huizheng Che Quanliang Chen Yaqiang Wang Junying Sun Xiaochun Zhang Sai Lu Jianping Guo Hong Wang Xiaoye Zhang | 2014 | Particuology2014，12，2： | 1 |
| 18 | SMRT sequencing and ddPCR reveal the complexity of developmental trajectories and temporal dynamics of gut bifidobacterial communities in infants显示文摘Infant intestinal microbiome is closely linked with health and risk of disease. Bifidobacterium are important components of the infant gut and are known to confer various health effects on the host. However, few studies have described the precise composition and dynamics of early infant gut bifidobacterial communities. Thus, this was a pilot study aiming to describe the developmental trajectories and temporal dynamics of bifidobacterial communities in infants before 6 months of age. A total of 28 fecal samples from 4 infants(GF, ZZ, QM, TN, respectively)were collected and analyzed after 5, 15, 30, 60, 90, 120, 150, and 180 days of birth by a bifidobacteria-target method(based on single-molecule real-time sequencing of partial bifidobacterial rpsK genes)in conjunction with droplet digital polymerase chain reaction(ddPCR). The infant fecal microbiota comprised a total of 11 bifidobacterial species, including 4 major species, i.e., B. dentium(37.35%), B. catenulatum(32.04%), B. breve(22.24%), and B. animalis(8.02%). The infant microbiota showed highly individualized developmental trajectories. The leading species for GF was B. catenulatum, with a relatively stable developmental trajectory. In ZZ, B. breve was enriched, and the developmental trajectory was rather fluctuating. The most abundant species for QM and TN was B. dentium. The developmental trajectory of B. dentium in QM showed a trend of gradual decrease, whereas an opposite trend was seen in samples of TN. The results of ddPCR confirmed large variations in quantities of bifidobacteria between infants and suggested discordances in temporal dynamics of bifidobacterial communities during the first half year of infancy. In conclusion, our results suggested that the early infant gut bifidobacterial microbiota was highly complex and temporal dynamics, with individualized developmental trajectories, which should be considered in future research of infant gut microbiota. | Xu Gao Tao Zhang Xiaoye Bai Qiannan Wen Dongyu Li Lai-Yu Kwok Heping Zhang Zhihong Sun | 2023 | Food Science and Human Wellness2023，12，5： | 0 |
| 19 | Fast Compass Alignment for Strapdown Inertial Navigation System显示文摘Initial alignment is the precondition for strapdown inertial navigation system(SINS)to navigate.Its two important indexes are accuracy and rapidity,the accuracy of the initial alignment is directly related to the working accuracy of SINS,but in self-alignment,the two indexes are often contradictory.In view of the limitations of conventional data processing algorithms,a novel method of compass alignment based on stored data and repeated navigation calculation for SINS is proposed.By means of data storage,the same data is used in different stages of the initial alignment,which is beneficial to shorten the initial alignment time and improve the alignment accuracy.In order to verify the correctness of the compass algorithm based on stored data and repeated navigation calculation,the simulation experiment was done.In summary,when the computer performance is sufficiently high,the compass alignment method based on the stored data and the forward and reverse navigation calculation can effectively improve the alignment speed and improve the alignment accuracy. | Jin Sun Dengyin Zhang Xiaoye Shi Fei Ding | 2020 | Computers, Materials & Continua2020，，11： | 0 |
| 20 | Rate-Energy Tradeoff for Wireless Simultaneous Information and Power Transfer in Full-Duplex and Half-Duplex Systems显示文摘In this paper,we study the rate-energy tradeoff for wireless simultaneous in-formation and power transfer in full-duplex and half-duplex scenarios.To this end,the weighting function of energy efficiency and transmission rate,as rate-energy tradeoff metric is first introduced and the metric optimization problem is formulated.Applying Karush-Kuhn-Tucker(KKT)conditions for Lagrangian optimality and a series of mathematical approximations,the metric optimization problem can be simplified.The closed-form solution of the power ratio is obtained,building direct relationship between power ratio and the rate-energy tradeoff metric.By choosing power ratio,one can make the tradeoff between information rate and harvested power in a straightforward and efficient way.Using the method similar to the half duplex systems,the optimal power ratio can be obtained in the full duplex systems,so as to balance the information transmission rate and energy transmission efficiency.Simulation results validate that the information rate is non-increasing with harvested power in half-duplex systems and the tradeoff of information rate and harvested power can be simply made.In the full duplex systems,the power ratio solution of the rate-energy tradeoff metric optimization problem can be used as the approximate optimal solution of the optimization problem and the approximation error is negligible. | Xiaoye Shi Jin Sun Dongming Li Fei Ding Zhaowei Zhang | 2020 | Computers, Materials & Continua2020，，11： | 0 |
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