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Global modeling 2^(nd)-order ionospheric delay and its effects on GNSS precise positioning

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Science China(Physics,Mechanics & Astronomy) 2011年第6期54卷 1059-1067页

作者： ZHANG HongPing lv HaiXia LI Min shi Chuang State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430070China GNSS Research Center Wuhan UniversityWuhan 430079China School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China

Ionospheric delay is one of the major error sources in GNSS navigation and ***,the dual-frequency technique is the most widely used in ionospheric refraction ***,dual-frequency measurements can only eliminate the first-order term of ionospheric delay,while the effect of the second-order term on GNSS observations may be several *** this paper,two models,the International Reference Ionosphere (IRI) 2007 and International Geomagnetic Reference Field (IGRF) 11 are used to estimate the second-order term through the integral calculation ***,the simplified single layer ionosphere model in a dipole moment approximation for the earth magnetic field is *** the traditional integral calculation method requires large calculation load and takes much time,it is not convenient for practical ***,although the simplified single layer ionosphere model is simple to implement,it results in larger *** this study,second-order term ionospheric correction formula proposed by Hoque (2007) is improved for estimating the second-order term at a global ***,it is more practicable to estimate the second-order *** importantly,its results have a higher precision of the sub-millimeter level for a global scale in normal *** with Hoque's original regional correction model,which calculates coefficients through polynomial fitting of elevation and latitudes,this study proposes a piece-wise look-up table and interpolation technique to modify Hoque *** utilizing a table file,the modified Hoque model can be conveniently implemented in an engineering software package,like as PANDA in this *** applying the proposed scheme for the second-order ionospheric correction into GNSS precise positioning in both PPP daily and epoch solutions,the results have shown south-shift characteristics in daily solution at a global scale and periodic change with VTEC daily variation in epoch positioning s

关键词： ionospheric delay second-order ionospheric correction GNSS precise positioning

A Dual-Platform Laser Scanner for 3D Reconstruction of Dental Pieces

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Engineering 2018年第6期4卷 796-805页

作者： Shuming Yang Xinyu shi Guofeng Zhang Changshuo lv State Key Laboratory for Manufacturing System Engineering Xi’an Jiaotong UniversityXi’an 710049China

This paper presents a dual-platform scanner for dental reconstruction based on a three-dimensional(3D)laser-scanning *** scanner combines translation and rotation platforms to perform a holistic scanning.A hybrid calibration method for laser scanning is proposed to improve convenience and *** method includes an integrative method for data collection and a hybrid algorithm for data *** integrative method conveniently collects a substantial number of calibrating points with a stepped gauge and a pattern for both the translation and rotation *** hybrid algorithm,which consists of a basic model and a compensation network,achieves strong stability with a small degree of *** experiments verified the hybrid calibration method and the scanner application for the measurement of dental *** typical dental pieces were measured,and the experimental results demonstrated the validity of the measurement that was performed using the dual-platform *** method is effective for the 3D reconstruction of dental pieces,as well as that of objects with irregular shapes in engineering fields.

关键词： Laser scanning Hybrid calibration Neural network Dental pieces

A series of novel Zn(Ⅱ) and Mn(Ⅱ) metal-organic frameworks constructed by 2,4-bis-oxyacetate-benzoic acid: syntheses, structures and photoluminescence

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Science China Chemistry 2015年第3期58卷 448-456页

作者： Yan lv Pei shi Wei Shen Xiaoju Chen Guoliang Zhao College of Chemistry and Life Science Zhejiang Normal University Xingzhi College Zhejiang Normal University

A new carboxylic acid ligand, 2,4-bis-oxyacetate-benzoic acid(H3BOABA), was designed and introduced to construct novel metal-organic framework materials. [Zn Na(BOABA)(phen)(H2O)]·H2O(1), Zn Na(BOABA)(2), Mn3(BOABA)2(phen)2(3), [Mn2(BOABA)(OH)]·(H2O)2(4)(CCDC: 885138, 885137, 894225, 883094) were hydrothermally synthesized and characterized by elemental analysis, IR spectra and thermal gravimetric analyses. Crystal structures of the complexes were determined by single crystal X-ray diffraction method. Complex 1 is a one dimensional double edges non-interpenetrated framework decorated by the phen ligands on the surface. Complex 2 is an unique three dimensional open framework, consisting of Zn(II) and Na(I). Complex 3 is an unique double edges one dimensional MOF containing a [Mn3(BOABA)2(phen)2]n non-interpenetrated structure. Complex 4 is a two dimensional plane structure containing two Mn atoms in the same coordination environment. The interaction between four complexes and DNA were studied by Et Br fluorescence probe. Meanwhile, photoluminescence studies revealed that these four complexes display strong fluorescent emission bands in the solid state at room temperature.

关键词： Zn and Mn complexes 2 4-bis-oxyacetate-benzoic acid crystal structure DNA binding photoluminescence

Abrupt onset of type 1 diabetes mellitus during recombinant interferon-alpha 2b therapy in a patient with chronic hepatitis B

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World Journal of Gastroenterology 2008年第29期14卷 4713-4715页

作者： Yuan-Yuan lv Bing-Yin shi Hui Guo Department of Endocrinology First Affiliated Hospital Medical School of Xi'an Jiaotong University Xi'an 710061 Shaanxi Province China

We describe a case of a 33-year-old female patient with chronic hepatitis B who developed type 1 diabetes mellitus (DM) after a 13-mo period of treatment with recombinant human interferon-alpha (IFN-α) 2b. The patient presented with polydipsia, polyuria, hypergly-cemia, diabetic ketoacidosis, combined with C-peptide secretion defi ciency and positive islet cell autoantibody (ICAb). IFN-α 2b treatment was terminated and in-stead insulin treatment was initiated. Five months after cessation of the recombinant human IFN-α 2b therapy, the patient remained insulin-dependent. Her serum HBV DNA became negative and serum transaminase returned to the normal level after a 10-mo period of IFN therapy. Type 1 DM induced by IFN-α is relatively rare in patients with chronic hepatitis B. We should pay more attention to patients on IFN-α therapy to avoid destruction of pancreatic beta cells. This is the first case report from China.

关键词： Interferon-alpha Islet cell autoantibody Type 1 diabetes mellitus Autoimmune disease Chronichepatitis B

Xi'an consensus on magnetic surgery

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Hepatobiliary Surgery and Nutrition 2019年第2期8卷 177-178页

作者： Yi lv Yuan shi 无 Department of Hepatobiliary Surgery Institute of Advanced Surgical Technology and EngineeringThe First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061China National Local Joint Engineering Research Center for Precision Surgery&Regenerative Medicine Xi’an 710061China Organ Transplantation Center Tianjin First Center HospitalTianjin 300190China Scientific Committee of the First International Conference of Magnetic Surgery

The interest in magnetic surgery has increased over the past decade following the development of minimally invasive *** surgery is defined as surgical treatment by utilization of magnetic ***,magnetic surgery includes but is not limited to magnetic compression anastomosis(Magnamosis),magnetic anchoring technique,magnetic navigation technique,magnetic sphincter augmentation,self-assembling magnets for endoscopic intestinal bypass,magnetic compression ostomy,correction of congenital deformities,*** surgery is developing rapidly and created a new surgical field.

关键词： magnetic field. correction

Protein farnesylation negatively regulatesbrassinosteroid signaling via reducing BES1 stabilityinArabidopsis thaliana^(∞)

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Journal of Integrative Plant Biology 2021年第7期63卷 1353-1366页

作者： Zengxiu Feng Hongyong shi Minghui lv Yuang Ma Jia Li Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations School of Life SciencesLanzhou UniversityLanzhou 730000China

Brassinosteroids(BRs)are a group of steroidal phytohormones,playing critical roles in almost all physiological aspects during the life span of a *** Arabidopsis,BRs are perceived at the cell surface,triggering a reversible phosphorylation-based signaling cascade that leads to the activation and nuclear accumulation of a family of transcription factors,represented by BES1 and *** famesylation is a type of post-translational modification,functioning in many important cellular *** studies demonstrated a role of famesylation in BR biosynthesis via regulating the endoplasmic reticulum localization of a key bassino-lide(BL)biosynthetic enzyme *** such a process is also involved in BR signaling is not un***,we demonstrate that protein famesylation is involved in mediating BR signaling in Arabidopsis.A loss-of-function mutant of EN HANCED RESPONSE TO ABA 1(iERA1).encoding a(3 subunit of the protein famesyl transferase hoi oenzyme,can alter the BL sensitivity of bak1~4 from a reduced to a hypersensitive level,era 7 can partially rescue the BR defective phenotype of a hetero zygous mutant of bin2-1,a gain-of function mutant of BIN2 which encodes a negative regulator in the BR *** genetic and biochemical analyses revealed that ERA1 plays a significant role in regulating the protein stability of BES1.

关键词： Arabidopsis BES1 brassinolide brassinosteroids protein famesylation

Realizing simultaneously enhanced energy and power density fullcell construction using mixed hard carbon/Li_(4)Ti_(5)O_(12) electrode

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Rare Metals 2021年第1期40卷 65-71页

作者： shi-Fei Huang Yao lv Da Tie Yang Yu Yu-Feng Zhao State Key Laboratory of Metastable Materials Science and Technology Key Laboratory of Applied ChemistryYanshan UniversityQinhuangdao 066004China Institute of Sustainable Energy Shanghai UniversityShanghai 200444.China

Practical applications of lithium-ion batteries(LIBs)with both high energy and power density are urgently demanded,which require suitable charge/discharge platform,fast charge-transfer kinetics,as well as optimal solid electrolyte interphase(SEI)layer of electrode *** this work,a high-performance lithium-ion battery(LIB)full cell was assembled by using commercial LiNi_(0.33)Co_(0.33)Mn_(0.33)O_(2)(NCM111)as the positive electrode and mixed Li_(4)Ti_(5)O_(12)(LTO)/hard carbon(HC)as the negative *** reveals that the component ratio between LTO and HC plays a critical role in manipulating the electric conductivity and the electro-reaction *** electrochemical test results show that when the content of HC is 10 wt%,the as-constructed full cell demonstrates the best electrochemical,with a maximum energy density of 149.2 Wh·kg^(-1) and a maximum power density of2195 W·kg^(-1) at 10 A·g^(-1)(30 C).This outperforms all the assembled systems within our work range and the state-ofthe-art *** NCM//Li_(4)Ti_(5)O_(12)+10 wt%HC battery system also exhibits a good capacity retention after1000 cycles at the current density of 1 A·g^(-1).This work provides a new approach to enhance the full-cell performance by mixing electrode materials with different charge potentials and reaction kinetics.

关键词： Hard carbon NCM111 LTO/HC Lithium-ion battery

Endoscopic magnetic compression stricturoplasty for congenital esophageal stenosis:A case report

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World Journal of Clinical Cases 2022年第33期10卷 12313-12318页

作者： shi-Qi Liu Yi lv Rui-Xue Luo Department of Nursing The Medical CollegeXijing UniversityXi’an 710123Shaanxi ProvinceChina Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina The Corrosion&Protection Research Lab Northwest Institute for Nonferrous Metal ResearchXi’an 710016Shaanxi ProvinceChina

BACKGROUND Congenital esophageal stenosis(CES)is a rare malformation of the digestive *** dilation and thoracotomy have been the main treatments for ***,there is no well-defined management *** compression stricturoplasty(MCS)has been used in refractory esophageal stricture in children after esophageal *** SUMMARY We describe the first case of MCS for CES in one female child *** child(aged 3 years and 1 mo)was admitted due to frequent vomiting and choking after eating complementary food since 7 mo *** and gastroendoscopy showed that there was stenosis in the lower esophagus,suggesting a diagnosis of *** patient did not receive any treatment for esophageal stricture including surgery or endoscopic dilation procedures before *** procedure was smoothly conducted without *** 24 mo after MCS,durable esophageal patency without dysphagia was *** MCS may serve as an alternative and efficient method for patients with CES.

关键词： Congenital esophageal stenosis Magnetic compression stricturoplasty Endoscopy Case report

Sharp learning rates of coefficient-based l^q-regularized regression with indefinite kernels

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Science China Mathematics 2013年第8期56卷 1557-1574页

作者： lv ShaoGao shi DaiMin XIAO QuanWu ZHANG MingShan Statistics School Southwestern University of Finance and Economics Microsoft Search Technology Center Asian College of Energy and Electronics Hohai University

Learning with coefficient-based regularization has attracted a considerable amount of attention in recent years, on both theoretical analysis and applications. In this paper, we study coefficient-based learning scheme （CBLS） for regression problem with /q-regularizer （1 〈 q ≤ 2）. Our analysis is conducted under more general conditions, and particularly the kernel function is not necessarily positive definite. This paper applies concentration inequality with/2-empirical covering numbers to present an elaborate capacity dependence analysis for CBLS, which yields sharper estimates than existing bounds. Moreover, we estimate the regularization error to support our assumptions in error analysis, also provide an illustrative example to further verify the theoretical results.

关键词： learning theory coefficient-based regularization indefinite kernel covering number reproducingkernel Hilbert spaces