|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | SIS accuracy and service performance of the BDS-3 basic system显示文摘On December 27,2018,the basic system of the third-generation BeiDou navigation satellite system(BDS-3)completed the deployment of its constellation of 18 MEO networking satellites as well as the construction of the operation control system(OCS)and began to provide basic navigation services to users worldwide.Compared with BDS-2,BDS-3 aims to offer users better navigation signals and higher precision with a series of new technologies.For example,the spaceborne atomic clock of BDS-3 is upgraded for higher performance,the Ka-band inter-satellite link is adopted for inter-satellite ranging and communication,and new B1C and B2a signals are broadcast in addition to B1I and B3I signals(compatible with BDS-2).In addition,a 9-parameter model based on a spherical harmonic function is employed for ionospheric delay corrections.Using the observation data from 18 satellites of the basic system,this paper conducts a comprehensive evaluation of the pseudorange measurement characteristics,signal-in-space(SIS)accuracy of navigation messages and global service capability of BDS-3.The results indicate that the pseudorange measurement multipath effect and observation noise of BDS-3 satellites are better than those of BDS-2;additionally,with the support of inter-satellite links,the user range error(URE)of the BDS-3 satellite broadcast ephemeris is better than 10 cm,the precision of the broadcast clock parameter is better than 1.5 ns,and the SIS accuracy is better than 0.6 m overall.Different from the traditional Klobuchar model,the BeiDou global broadcast ionospheric delay correction model(BDGIM)can provide ionospheric delay corrections better than 70%for worldwide single-frequency users.The service capability evaluation of the basic system consists mainly of the accuracy improvement of the B1I and B3I signals according to BDS-2 as well as the global positioning accuracy of the new signals.These results prove that the BDS-3 basic system has achieved the design goal;that is,both the horizontal and the vertical global positioning accuracies are better than 10 m(95%).In the future,6 MEO satellites as well as 3 GEO satellites and 3 IGSO satellites for regional enhancement purposes will be deployed for full operation;consequently,BDS-3 will definitely provide a higher SIS accuracy and better service capability. | JinPing Chen XiaoGong Hu ChengPan Tang ShanShi Zhou YuFei Yang JunYang Pan Hui Ren YueXin Ma QiuNing Tian Bin Wu Yang Yu | 2020 | Science China(Physics,Mechanics & Astronomy)2020，63，6： | 14 |
| 2 | Optimizing Building Envelope Dimensions for Passive Solar Houses in the Qinghai-Tibetan Region: Window to Wall Ratio and Depth of Sunspace显示文摘It has been a focus to reduce the energy consumption and improve the space heating performance of high-altitude buildings in winter seasons. In view of the abundant solar energy resources of the high-altitude region, the establishment of passive solar houses should be an effective strategy to deal with the problem of thermal comfort. Both window to wall ratio(WWR) and sunspace depth are of vital importance to determine the thermal comfort level of passive solar houses, while there are limited studies on analyzing their impacts on passive solar houses in high-altitude regions. Therefore, this study is designed to examine how WWR and sunspace depth affect space heating of passive solar houses in the Qinghai-Tibetan region. To be specific, the hourly radiation temperature variations and percentages of dissatisfaction of the residential building with different sunspace depth/WWR(including 0.9 m/33%, 0.9 m/45%, 0.9 m/60%, 1.2 m/33% and 1.5 m/33%) were quantitatively examined. Results indicated that under the condition of 0.9 m/45%, the overall average radiation temperature of the building was approximately 16°C during the entire heating season, which could better satisfy the heating requirements. Meanwhile, the average temperature was higher, and the thermal comfort level was better under the ratio of 45% or the depth of 1.5 m, when only an individual factor in either ratio or depth was considered. These findings can provide references for the determination of dimensions of passive solar houses in high-altitude regions. | LIU Zhijian WU Di LI Junyang YU Hancheng HE Baojie | 2019 | Journal of Thermal Science2019，28，6： | 4 |
| 3 | Accessing Alignments of Ontologies via IoT Based on SKOS Data Model显示文摘Many ontologies are provided to representing semantic sensors data.However,heterogeneity exists in different sensors which makes some service operators of Internet of Thing(IoT) difficult(such as such as semantic inferring,non-linear inverted index establishing,service composing) .There is a great deal of research about sensor ontology alignment dealing with the heterogeneity between the different sensor ontologies,but fewer solutions focus on exploiting syntaxes in a sensor ontology and the pattern of accessing alignments.Our solution infers alignments by extending structural subsumption algorithms to analyze syntaxes in a sensor ontology,and then combines the alignments with the SKOS model to construct the integration sensor ontology,which can be accessed via the IoT.The experiments show that the integration senor ontology in the SKOS model can be utilized via the IoT service,and the accuracy of our prototype,in average,is higher than others over the four real ontologies. | Xiulei Liu Xia Hou Junyang Yu Ying Gao Yue Zhang Yingying Zhang | 2017 | China Communications2017，14，6： | 3 |
| 4 | Misiurewicz points on the Mandelbrot-like set concerning renormalization transformation显示文摘We study Misiurewicz points on the parameter space about a family of rational maps Tλ concerning renormalization transformation in statistical mechanic. We determine the intersection points of the Julia set J(Tλ) and the positive real axis R+and discuss the continuity of the Hausdorff dimension HD(J(f)) about real parameter λ. | GAO JunYang QIAO JianYong ZHAI Yu | 2014 | Science China Mathematics2014，57，12： | 2 |
| 5 | Delivery of Survivin siRNA Using Cationic Diphenylalanine Vesicles显示文摘Small interfering RNA(siRNA) has been proved to be a powerful tool for silencing target gene in cells, raising the possibility that siRNA can be employed as a therapy for treating cancers and other genetic diseases. However, siRNA transfection has the limitation due to the difficulty in the delivery of siRNA to target cells and tissues. To explore an efficient biocompatible siRNA delivery system, cationic diphenylalanine vesicles(CDPVs) were constructed to transfer survivin siRNA to human ovarian cancer cells. The morphology of CDPVs was characterized by scanning electron microscopy(SEM) and the distribution of survivin siRNA was characterized by confocal laser scanning microscopy, which reveal that diphenylalanine and the survivin siRNA were successfully co-delivered. After co-incubation for 48 h, the CDPVs/siRNA exhibited enhanced tumor cell growth inhabitation and apoptosis inducted in human SK-OV-3 ovarian carcinoma cells. Overall, CDPVs is an efficient siRNA delivery system and has a promising prospect for cancer therapy. | GUAN Shuwen YU Xiaoxuan LI Junyang XU Heng HAN Wenzhao SHI Guannan XU Jia WANG Liping | 2019 | Chemical Research in Chinese Universities2019，35，3： | 0 |
| 6 | Design and Implementation of Enterprise Recruitment Mini Program显示文摘Since the 21st century,the Internet has been updated and developed at an alarming speed.At the same time,WeChat applets are constantly improving and introducing new functions.Develop an enterprise recruitment system based on WeChat applets for the majority of job seekers and recruiter users,provide job seekers with easy-to-reach employment opportunities,and provide a convenient and clear screening environment for job seekers.The front-end part of the applet is developed using WeChat developer tools,and the back-end system is developed using MyEclipse.Use Spring Boot+Spring MVC framework,implemented in Java language.Data is managed using MySql database.The function of this company’s recruitment applet is similar to the ordinary traditional native recruitment APP.It achieves basic functions such as job search,job search,collection of jobs,delivery of resumes,viewing of the job search process,recruitment of job information,screening of job resumes,notification of interviews,etc. | Yu Xue Nan Wei Junyang Han Chishe Wang Moayad Aloqaily | 2021 | Journal of Cyber Security2021，3，3： | 0 |
| 7 | Size controllable single-crystalline Ni-rich cathodes for high-energy lithium-ion batteries显示文摘A single-crystalline Ni-rich(SCNR)cathode with a large particle size can achieve higher energy density,and is safer,than polycrystalline counterparts.However,synthesizing large SCNR cathodes(>5μm)without compromising electrochemical performance is very challenging due to the incompatibility between Ni-rich cathodes and high temperature calcination.Herein,we introduce Vegard’s Slope as a guide for rationally selecting sintering aids,and we successfully synthesize size-controlled SCNR cathodes,the largest of which can be up to 10μm.Comprehensive theoretical calculation and experimental characterization show that sintering aids continuously migrate to the particle surface,suppress sublattice oxygen release and reduce the surface energy of the typically exposed facets,which promotes grain boundary migration and elevates calcination critical temperature.The dense SCNR cathodes,fabricated by packing of different-sized SCNR cathode particles,achieve a highest electrode press density of 3.9 g cm^(-3)and a highest volumetric energy density of 3000 Wh L^(-1).The pouch cell demonstrates a high energy density of 303 Wh kg^(-1),730 Wh L^(-1)and 76% capacity retention after 1200 cycles.SCNR cathodes with an optimized particle size distribution can meet the requirements for both electric vehicles and portable devices.Furthermore,the principle for controlling the growth of SCNR particles can be widely applied when synthesizing other materials for Li-ion,Na-ion and K-ion batteries. | Ji-Lei Shi Hang Sheng Xin-Hai Meng Xu-Dong Zhang Dan Lei Xiaorui Sun Hongyi Pan Junyang Wang Xiqian Yu Chunsheng Wang Yangxing Li Yu-Guo Guo | 2023 | National Science Review2023，10，2： | 0 |
| 8 | Research on automatic spraying of single-walled carbon nanotubes and detection of spraying effects显示文摘Single-walled carbon nanotubes(SWNTs)have been introduced as compliant electrodes for dielectric elastomers(DEs)due to fault tolerance.To acquire a better electrostrictive strain and longer lifetime,it is essential to obtain a certain and uniform width of the SWNT electrode.To ensure uniform width manually,a small flux and longer time are necessary.Moreover,it is difficult to control the width of the electrode for the randomness of manual spraying.Therefore,a new type of automatic spraying process is presented in this paper.The width and homogeneity of the electrode can be easily controlled by certain parameters of the process.Two methods for detecting the homogeneity of the electrode are introduced in this paper:Measurement of surface resistance and luminosity.The coefficient of variation(CV)values detected by the two methods are virtually equal and less than 8%,which shows the feasibility of the detection method and homogeneity of automatic spraying.The speed of automatic spraying is 102 mm^(2)/s,which is higher than that of manual spraying.The spraying process and the method used to detect homogeneity in this paper provide a reference for the relevant processes. | Jianwen Zhao Jiangcheng Yu Junyang Niu Yong Ge Liwu Liu | 2014 | International Journal of Smart and Nano Materials2014，5，2： | 0 |
| 9 | ON THE PROBLEM OF UNIQUENESS AND DETERMINATION OF ALGEBRAIC FUNCTIONS显示文摘This paper gives the unicity theorem of algebraic functions and further inquires into the problem of determination of algebraic functions. | Yu Junyang(Institute of Mathematics, Academia Sinica) | 1991 | 中国科学院研究生院学报1991，8，1： | 0 |
| 10 | Iodine-assisted ultrafast growth of high-quality monolayer MoS_(2) with sulfur-terminated edges显示文摘Two-dimensional(2D)semiconductors have attracted great attention to extend Moore’s law,which motivates the quest for fast growth of high-quality materials.However,taking MoS_(2) as an example,current methods yield 2D MoS_(2) with a low growth rate and poor quality with vacancy concentrations three to five orders of magnitude higher than silicon and other commercial semiconductors.Here,we develop a strategy of using an intermediate product of iodine as a transport agent to carry metal precursors efficiently for ultrafast growth of high-quality MoS_(2).The grown MoS_(2) has the lowest density of sulfur vacancies(~1.41×10^(12) cm^(−2))reported so far and excellent electrical properties with high on/off current ratios of 108 and carrier mobility of 175 cm^(2) V^(−1) s^(−1).Theoretical calculations show that by incorporating iodine,the nucleation barrier of MoS_(2) growth with sulfur-terminated edges reduces dramatically.The sufficient supply of precursor and low nucleation energy together boost the ultrafast growth of sub-millimeter MoS_(2) domains within seconds.This work provides an effective method for the ultrafast growth of 2D semiconductors with high quality,which will promote their applications. | Qinke Wu Jialiang Zhang Lei Tang Usman Khan Huiyu Nong Shilong Zhao Yujie Sun Rongxu Zheng Rongjie Zhang Jingwei Wang Junyang Tan Qiangmin Yu Liqiong He Shisheng Li Xiaolong Zou Hui-Ming Cheng Bilu Liu | 2023 | National Science Open2023，2，4： | 0 |
| 11 | Sub-nanometer supramolecular rectifier based on the symmetric building block with destructive σ-interference显示文摘Molecular rectifier, as a basic function of molecular electronic devices, has attracted extensive attention for the opportunity in constructing sub-nanometer electronic devices. However, tunneling leakage current has a significant contribution as electronic devices shrink in size, which leads to a challenge in fabricating molecular rectifiers at the sub-nanometer scale. Here, we experimentally demonstrate a sub-nanometer molecular rectifier based on the supramolecular junction assembled between water and 1,4-diazabicyclo[2.2.2]octane (DABCO) molecule. The charge transport through DABCO and corresponding supramolecular junctions exhibits destructive σ-interference, ensuring a sharp conductance variation for transmission modulation. The supramolecular interaction between DABCO and water readily introduces the asymmetric electrode-molecule interaction, which combines with the destructive σ-interference to support the sub-nanometer rectification. | Longfeng Huang Yu Zhou Yaorong Chen Jingyao Ye Junyang Liu Zongyuan Xiao Chun Tang Haiping Xia Wenjing Hong | 2021 | Science China Chemistry2021，64，8： | 0 |
| 12 | Intermolecular coupling enhanced thermopower in single-molecule diketopyrrolopyrrole junctions显示文摘Sorting out organic molecules with high thermopower is essential for understanding molecular thermoelectrics.The intermolecular coupling offers a unique chance to enhance the thermopower by tuning the bandgap structure of molecular devices,but the investigation of intermolecular coupling in bulk materials remains challenging.Herein,we investigated the thermopower of diketopyrrolopyrrole(DPP)cored single-molecule junctions with different coupling strengths by varying the packing density of the self-assembled monolayers(SAM)using a customized scanning tunneling microscope break junction(STM-BJ)technique.We found that the thermopower of DPP molecules could be enhanced up to one order of magnitude with increasing packing density,suggesting that the thermopower increases with larger neighboring intermolecular interactions.The combined density functional theory(DFT)calculations revealed that the closely-packed configuration brings stronger intermolecular coupling and then reduces the highest occupied molecular orbital(HOMO)-lowest unoccupied molecular orbital(LUMO)gap,leading to an enhanced thermopower.Our findings offer a new strategy for developing organic thermoelectric devices with high thermopower. | Chao Fang Renad Almughathawi Qingqing Wu Wenqiang Cao Hang Chen Songjun Hou Yu Gu Hewei Zhang Yi Zhao Jueting Zheng Guopeng Li Jia Shi Junyang Liu Bing-Wei Mao Zitong Liu Colin J.Lambert Wenjing Hong | 2023 | National Science Open2023，2，1： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员