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Positive Rate of Different Hepatitis B Virus Serological Markers in Peking Union Medical College Hospital,a General Tertiary Hospital in Beijing 被引量:1
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作者 Yue-qiu Zhang Sai-nan Bian +7 位作者 Xiao-qing Liu Shao-xia Xu Li-fan Zhang Bao-tong Zhou Wei-hong Zhang Yao Zhang Ying-chun Xu Guo-hua Deng 《Chinese Medical Sciences Journal》 CAS CSCD 2016年第1期17-22,共6页
Objectives To investigate the positive rate of different hepatitis B virus (HBV) serological markers, and the demographic factors related to HBV infection. Methods We enrolled all patients tested for HBV serologica... Objectives To investigate the positive rate of different hepatitis B virus (HBV) serological markers, and the demographic factors related to HBV infection. Methods We enrolled all patients tested for HBV serological markers, such as HBV surface antigen (HBsAg), HBV surface antibody (HBsAb), hepatitis B e antigen (HBeAg), hepatitis B e antibody (HBeAb), HBV core antibody (HBcAb), and HBV-DNA from July 2008 to July 2009 in Peking Union Medical College Hospital. The positive rate of each HBV serological marker was calculated according to gender, age, and department, respectively. The positive rates of HBV-DNA among patients with positive HBsAg were also analyzed. Results Among 27 409 samples included, 2681 (9.8%) were HBsAg positive. When patients were divided into 9 age groups, the age-specific positive rate of HBsAg was 1.2%, 9.6%, 12.3%, 10.9%, 10.3%, 9.7%, 8.0%, 5.8%, and 4.3%, respectively. The positive rate of HBsAg in non-surgical department, surgical department, and health examination center was 16.2%, 5.8%, and 4.7%, respectively. The positive rate of HBsAg of males (13.3%) was higher than that of females (7.3%, P=0.000). Among the 2681 HBsAg (+) patients, 1230 (45.9%) had HBV-DNA test, of whom 564 (45.9%) were positive. Patients with HBsAg (+), HBeAg (+), and HBcAg (+) result usually had high positive rate of HBV-DNA results (71.8%, P=0.000). Conclusions Among this group of patients in our hospital, the positive rate of HBsAg was relatively high. Age group of 20-29, males, and patients in non-surgical departments were factors associated with high positive rate of HBsAg. 展开更多
关键词 hepatitis B virus infection positive rate hepatitis B virus serological markers demographic factors
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The relationship between the distribution of HBcAg in liver cells and the pathological manifestations of the liver in 429 HBeAg-positive chronic HBV-infected individuals
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作者 Fan Nie Chang-Chun Zeng +4 位作者 Guang-Dong Tong Mu-Min Shao Xiao-Hua Le Xin Deng Da-Qiao Zhou 《Gastroenterology & Hepatology Research》 2024年第3期10-15,共6页
Background:The natural history of chronic HBV infection is typically characterized by four stages:the immune tolerance period,the immune clearance period,the immune control period,and the immune escape period.These st... Background:The natural history of chronic HBV infection is typically characterized by four stages:the immune tolerance period,the immune clearance period,the immune control period,and the immune escape period.These stages are associated with the distribution of HBcAg in liver cells;however,this relationship remains a topic of broad debate within the field of liver disease.To objectively and quantitatively measure the intracellular distribution of HBcAg,this paper aims to design a method referred to as the“layered evaluation method”and to examine its validation.Methods:The distribution of HBcAg in liver cells is assessed using Image Pro Plus image processing software,along with calculations of cytoplasmic and nuclear positive staining rates.Results:The findings indicate that the highest proportion of patients exhibited a positive cytoplasmic expression rate ranging from 0-2.5%.More than 40% of the total sample was categorized within the 0-2.5% positive nuclear expression range.The HBcAg cytoplasmic positive staining rates were classified into five levels:a cytoplasmic HBcAg positive staining rate of less than 0.05% is designated as level 0,indicating negative expression;a staining rate between 0.05% and 5% is classified as level 1;a rate from 5% to less than 10% is classified as level 2;a rate from 10% to less than 20% is classified as level 3;and a nuclear positivity rate exceeding 20% is classified as level 4.Conclusion:The inflammatory activity grade in these patients was positively correlated with the cytoplasmic distribution of HBcAg.Furthermore,the nuclear distribution rate of HBcAg was significantly higher in the G3 group compared to the other groups. 展开更多
关键词 distribution of HBcAg pathological manifestations of the liver positive staining rate
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A comparative study on the reactivity of charged Ni-rich and Ni-poor positive electrodes with electrolyte at elevated temperatures using accelerating rate calorimetry
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作者 Dongxu Ouyang Yulong Liu +2 位作者 Ines Hamam Jian Wang Jeff Dahn 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第9期523-530,共8页
The reactivity between charged Li(Li_(0.115)Mn_(0.529)Ni_(0.339)Al_(0.017))O_(2)(Li-rich),single crystal Li(Ni_(0.8)Mn_(0.1)Co_(0.1))O_(2)(SC-NMC811),LiFePO_(4)(LFP) and LiMn_(0.8)Fe_(0.2)PO_(4)(LMFP) positive electro... The reactivity between charged Li(Li_(0.115)Mn_(0.529)Ni_(0.339)Al_(0.017))O_(2)(Li-rich),single crystal Li(Ni_(0.8)Mn_(0.1)Co_(0.1))O_(2)(SC-NMC811),LiFePO_(4)(LFP) and LiMn_(0.8)Fe_(0.2)PO_(4)(LMFP) positive electrodes at different states of charge(SOCs) and traditional carbonate-based electrolyte at elevated temperatures is systematically studied using accelerating rate calorimetry(ARC).The results show that the SOC greatly affects the thermal stability of the Li-rich and SC-NMC811 when traditional carbonate-based electrolyte is used.Although an increase in the SOC increases the energy density of lithium-ion cells,it also increases the reactivity between charged Li-rich and SC-NMC811 samples with electrolyte at elevated temperatures.In comparison with SC-NMC811,the Li-rich samples are much more stable at elevated temperatures,and the latter have higher specific capacity.SC-NMC811 samples are less reactive than traditional polycrystalline NMC811.Both LFP and LMFP samples show excellent thermal stability at elevated temperatures.The substitution of Fe by Mn in the olivine series positive materials does not impact the reactivity with electrolyte. 展开更多
关键词 Lithium-ion cells Accelerating rate calorimetry positive electrodes Safety
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Survey and analysis on positive rate of HCV,HBsAg,HIV and syphilis in hemophilia Ap atients during 1992~2000
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《中国输血杂志》 CAS CSCD 2001年第S1期335-,共1页
关键词 HBSAG HCV Survey and analysis on positive rate of HCV HBsAg HIV and syphilis in hemophilia Ap atients during 1992 rate HIV
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Study of the Effect of Two New Types of IUDs,TCu380A and GyneFix on the Positive Rate of Chlamydia Trahmatis
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作者 顾向应 李敬之 《Journal of Reproduction and Contraception》 CAS 2000年第1期98-102,共5页
To analyze the effect of two types of IUDs, TCu380A and GyneFix on the positive rate of Chlamydia Trahmatis (CT). Methods The TCu380A and GyneFix IUDs were compared in a randomized was for the one year and two year... To analyze the effect of two types of IUDs, TCu380A and GyneFix on the positive rate of Chlamydia Trahmatis (CT). Methods The TCu380A and GyneFix IUDs were compared in a randomized was for the one year and two year positive rate of Chlamydia Trahmatis (CT) and with the control respectively. Results The one year positive rate of CT antigens was 5.63% of TCu380A and two year was 4.92%; the one year positive rate of CT antigens was 4.62% and two year was 5.08% of GyneFix. There was no significant difference in the positive rate of CT antigen between the TCu380A IUD, and GyneFix IUDs groups, while there were significant differences between the TCu380A IUD, GyneFix IUD and the controls (15.18%) respectively. Conclusion Both IUDs provide highly effective protection against CT infection. 展开更多
关键词 TCu380A IUD GyneFix IUD Chlamydia trachmatish the control respectively. Results The one year positive rate of CT antigens was 5.63% of TCu380A and two year was 4.92% the one year positive rate of CT antigens was 4.62% and two year was
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A Positive Analysis on Personal Saving Rate between America and China
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作者 WenshengSun Wei Li 《Chinese Business Review》 2005年第10期16-20,共5页
The level of saving not only influences the life of individuals, but also plays an important role in a country's development. Accordingly, the studying on saving is becoming a focus problem in modem life. In recent y... The level of saving not only influences the life of individuals, but also plays an important role in a country's development. Accordingly, the studying on saving is becoming a focus problem in modem life. In recent years, the personal saving rate in the United States has fallen sharply, but the personal saving rate in China is at an astoundingly high level. This paper studies this problem with the positive analysis method from the situation; the reasons of the saving rate disparity between the U.S. and .China, and put forward some proposals about how to deal with the saving problems. 展开更多
关键词 saving rate positive analysis countermeasures
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Cooperation Benefits Both Sides While Confrontation Harms——Thoughts on Strategic Positioning of Sino-U.S. Relations
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作者 Ma Zhengang 《China International Studies》 2006年第1期35-54,共20页
关键词 rate Relations Thoughts on Strategic positioning of Sino-U.S Cooperation Benefits Both Sides While Confrontation Harms
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Method for determining the position of landslide slip-surface with a typical inclinometric curves
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作者 CHEN Hao WU Hong-gang 《Journal of Mountain Science》 SCIE CSCD 2024年第2期413-432,共20页
In the actual monitoring of deep hole displacement,the identification of slip surfaces is primarily based on abrupt changes observed in the inclinometric curve.In conventional identification methods,inclinometric curv... In the actual monitoring of deep hole displacement,the identification of slip surfaces is primarily based on abrupt changes observed in the inclinometric curve.In conventional identification methods,inclinometric curves exhibiting indications of sliding can be categorized into three types:B-type,D-type,and r-type.The position of the slip surface is typically determined by identifying the depth corresponding to the point of maximum displacement mutation.However,this method is sensitive to the interval of measurement points and the observation scale of the coordinate axes and suffers from unclear sliding surfaces and uncertain values.Based on the variation characteristics of these diagonal curves,we classified the landslide into three components:the sliding body,the sliding interval,and the immobile body.Moreover,three different generalization models were established to analyze the relationships between the curve form and the slip surface location based on different physical indicators such as displacement rate,relative displacement,and acceleration.The results show that the displacement rate curves of an r-type slope exhibit a clustering feature in the sliding interval,and by solving for the depth of discrete points within the step phase,it is possible to determine the location of the slip surface.On the other hand,D-type slopes have inflection points in the relative displacement curve located at the slip surface.The acceleration curves of B-type slopes exhibit clustering characteristics during the sliding interval,while the scattered acceleration data demonstrate wandering characteristics.Consequently,the slip surface location can be revealed by solving the depth corresponding to the maximum acceleration with cubic spline interpolation.The approach proposed in this paper was applied to the monitoring data of a landslide in Yunnan Province,China.The results indicate that our approach can accurately identify the slip surface location and enable computability of its position,thereby enhancing applicability and reliability of the deep-hole displacement monitoring data. 展开更多
关键词 Inclinometric curve Slip-surface position Displacement rate Relative displacement Acceleration
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Photosynthesis adaption in Korean pine to gap size and position within Populus davidiana forests in Xiaoxing’anling, China 被引量:3
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作者 Xuannan Li Yahui Wang +2 位作者 Zhihui Yang Ting Liu Changcheng Mu 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第5期1517-1527,共11页
Forest gaps restrict the restoration of temperate secondary forest to broad-leaved Korean pine forest in zonal climax vegetation by affecting the growth of Korean pine(Pinus koraiensis).However,the photo synthetic ada... Forest gaps restrict the restoration of temperate secondary forest to broad-leaved Korean pine forest in zonal climax vegetation by affecting the growth of Korean pine(Pinus koraiensis).However,the photo synthetic adaptability of Korean pine to gap size and position within the gap is unclear.In order to explore the adaptability of young Korean pine(35 years) to different gap sizes in Xiaoxing’anling,photo synthetic capacity and microenvironmental factors(leaf temperature,light transmittance) of Korean pine needles in three positions in the gap(central,transition,and edge areas) were investigated.Three gaps were identified in the secondary Populus davidiana forest:a large 201 m^(2) gap,a middle 112 m^(2) gap,and a small 50 m^(2) gap;12 m^(2) of the understory was sampled as a control.The results show that:(1) maximum net photosynthetic rate(P_(max)) in needles of Korean pine growing in the large gap was higher than in the small gap,and P_(max) in the centre in the same gap was higher than in the transition and edge areas;(2) light saturation point(LSP) and photosynthetic quantum yield(AQY)of needles in the large gap were higher than in the small gap,while the light compensation point(LCP) and chlorophyll contents of needles were lower in the small gap;and,(3)P_(max) had a significant positive correlation with temperature and light transmittance.It is suggested that the larger the gap in secondary Populus davidiana forests,the greater the change in light intensity and temperatures,the stronger the light adaption of Korean pine needles and the higher the photosynthetic capacity.Therefore,in the recovery of broadleaved/Korean pine forests,suitable gaps should be created and gap microhabitats fully utilized to accelerate the restoration process. 展开更多
关键词 Pinus koraiensis Gap size position in the gap Maximum net photosynthetic rate
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Numerical and experimental investigation of leakage behavior at null position of high-pressure electro-pneumatic servo valve 被引量:2
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作者 ZHANG Di-jia GAO Long-long +2 位作者 WU Chuan ZHAO Zhi-xin LI Bao-ren 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第10期3117-3126,共10页
The high-pressure electro-pneumatic servo valve(HESV)is a core element of the high-pressure pneumatic servo system.The annular clearance and the rounded corner of the spool-sleeve can cause the leakage at null positio... The high-pressure electro-pneumatic servo valve(HESV)is a core element of the high-pressure pneumatic servo system.The annular clearance and the rounded corner of the spool-sleeve can cause the leakage at null position,thereby affecting high-precision control and stability of the servo system.This paper investigates the effects of the clearance structure on leakage behavior at null position of the HESV.A numerical approach was employed to evaluate the effects,and then a mathematical model was established to obtain the variation law of leakage flow rate at null position.The results indicate that the leakage flow rate at null position varies linearly with supply pressure and rounded corner radius,and is nonlinear as a quadratic concave function with annular clearance.The leakage flow rate of the annular clearance and the rounded corner varies with the valve opening in an invariable−nonlinear−linear trend.A test rig system of leakage behavior at null position of the HESV was built to confirm the validity of the numerical model,which agrees well with the conducted experimental study. 展开更多
关键词 high-pressure electro-pneumatic servo valve CLEARANCE leakage flow rate null position
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ATTITUDE RATE ESTIMATION BY GPS DOPPLER SIGNAL PROCESSING 被引量:1
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作者 HeSide GuoZhenyu 《Journal of Electronics(China)》 2003年第1期13-19,共7页
A method is presented for near-Earth spacecraft or aviation vehicle's attitude rate estimation by using relative Doppler frequency shift; of the Global Positioning System (GPS) carrier. It comprises two GPS receiv... A method is presented for near-Earth spacecraft or aviation vehicle's attitude rate estimation by using relative Doppler frequency shift; of the Global Positioning System (GPS) carrier. It comprises two GPS receiving antennas, a signal processing circuit and an algorithm. The whole system is relatively simple, the cost and weight, as well as power consumption, are very low. 展开更多
关键词 Attitude rate determination Global positioning system SATELLITE Doppler frequency shift
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Comparison of availability and reliability among different combined-GNSS/RNSS precise point positioning 被引量:1
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作者 Chen Jian Yue Dongjie +2 位作者 Zhu Shaolin Liu Zhiqiang Dai Jianbiao 《High Technology Letters》 EI CAS 2020年第3期235-242,共8页
With emergence of the BeiDou Navigation Satellite System(BDS), the Galileo Satellite Navigation System(Galileo), the Quasi-Zenith Satellite System(QZSS)and the restoration of the Global Navigation Satellite System(GLO... With emergence of the BeiDou Navigation Satellite System(BDS), the Galileo Satellite Navigation System(Galileo), the Quasi-Zenith Satellite System(QZSS)and the restoration of the Global Navigation Satellite System(GLONASS), the single Global Positioning System(GPS) has been gradually expanded into multiple global and regional navigation satellite systems(multi-GNSS/RNSS). In view of differences in these 5 systems, a consolidated multi-GNSS/RNSS precise point positioning(PPP) observation model is deduced in this contribution. In addition, the performance evaluation of PPP for multi-GNSS/RNSS is conducted using a large number of the multi-GNSS experiment(MGEX) station datasets. Experimental results show that multi-GNSS/RNSS can guarantee plenty of visible satellites effectively. Compared with single-system GPS, PDOP, HDOP, and VDOP values of the multi-GNSS/RNSS are improved by 46.8%, 46.5% and 46.3%, respectively. As for convergence time, the static and kinematic PPP of multi-GNSS/RNSS are superior to that of the single-system GPS, whose reliability, availability, and stability drop sharply with the increasing elevation cutoff. At satellite elevation cutoff of 40 °, the single-system GPS fails to carry out continuous positioning because of the insufficient visible satellites, while the multi-GNSS/RNSS PPP can still get positioning solutions with relatively high accuracy, especially in the horizontal direction. 展开更多
关键词 precise point positioning(PPP) positioning accuracy convergence rate multiple global and regional navigation satellite systems(multi-GNSS/RNSS) reliability and availability
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Macroeconomic control of interest rate in China
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作者 姜鸣 叶元煦 何绍元 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2002年第3期297-301,共5页
The macroeconomic control of interest rate is studied using the elastic theory and correlation analysis and the concrete influence of interest rate on the consumption, savings and investment in China are investigated.... The macroeconomic control of interest rate is studied using the elastic theory and correlation analysis and the concrete influence of interest rate on the consumption, savings and investment in China are investigated. It is pointed out that although the interest rate mechanisms in China has gone through several adjustments and reforms, the results are not yet fully up to expectations. The interest rate does not adjust the national economic structure, and direct the trend of funds, nor regulate the general social supply and demand and balance the price and currency in circulation, to achieve a rational distribution of social resources. The interest rate policy of Central Bank does not have much actual influence on the economic departments, and this influence was continuously weakened in recent years. Countermeasures are suggested for improving the macro control of interest rate. 展开更多
关键词 INTEREST rate REGULATION and control positive research
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Influence of Orifice Position Deviations on Distribution Performance of Gravity-Type Liquid Distributor Analyzed Through Mathematical Pathway
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作者 Jinsheng Sun Zhiwei Zhang +2 位作者 Chengtian Cui Tianpei Li Sheng Fu 《Transactions of Tianjin University》 EI CAS 2018年第2期152-159,共8页
The distribution performance of the gravity-type liquid distributor(GTLD) significantly affects column operation efficiency and the consequent product quality. In industrial settings, maldistribution is normally consi... The distribution performance of the gravity-type liquid distributor(GTLD) significantly affects column operation efficiency and the consequent product quality. In industrial settings, maldistribution is normally considered to be caused by vertical positional or coplanarity errors stemming from deflections associated with manufacture and installation, or even by excessive weight. The lack ofestimation protocols or standards impedes the description ofthis error, which influences the corresponding outflow rates. Given this situation, the paper proposes a lumped parameter, orifice position deviation(OPD), to facilitate the calculation of the relative discharge rate error(RDRE)based on a formula derivation, which allows the systematic analysis of the influence ofa single orifice or weir OPD.The paper introduces a sensitivity factor K as a concise and unified expression in theoretical RDREs for calibrating the influence of OPD on the RDREs ofgeometrically different orifices and weirs. With respect to the GTLD, a larger K indicates the need for more strict OPD requirements. The paper verifies that the extent of GTLD outflow nonuniformity is associated with diverging tendencies regarding its morphology, especially in the orifice and weir, which can be determined using our proposed procedures. 展开更多
关键词 Liquid DISTRIBUTOR Installation ORIFICE positION deviation Relative DISCHARGE rate error Sensitivity factor
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Detection of rotor position by harmonic back EMF of hybrid step motor
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作者 张劲松 徐殿国 王宗培 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1999年第3期85-88,共4页
The magnhc network model of a hybrid step motor is established by the air gap rate permeance method,and the expression of harmonic back EMF is deduced, and from the analysis above, a vovel use of harmonic backEMF sed ... The magnhc network model of a hybrid step motor is established by the air gap rate permeance method,and the expression of harmonic back EMF is deduced, and from the analysis above, a vovel use of harmonic backEMF sed to extract rotor peition is proposed and a new position sensor integral with the motoris designed .Experi-ments verified the correctness of the theorecal analysis. Ths type of rotor position sensor lays a foundation for closed-loop conrol of step motor. 展开更多
关键词 HYBRID step MOTOR air gap rate PERMEANCE magnetic network model HARMONIC BACK EMF position sensor
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CONVERGENCE RATE FOR ITERATES OF q-BERNSTEIN POLYNOMIALS
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作者 Xueyan Xiang Qian He Wenshan Yang 《Analysis in Theory and Applications》 2007年第3期243-254,共12页
Recently, q-Bernstein polynomials have been intensively investigated by a number of authors. Their results show that for q ≠ 1, q-Bernstein polynomials possess of many interesting properties. In this paper, the conve... Recently, q-Bernstein polynomials have been intensively investigated by a number of authors. Their results show that for q ≠ 1, q-Bernstein polynomials possess of many interesting properties. In this paper, the convergence rate for iterates of both q-Bernstein polynomials and their Boolean sum are estimated. Moreover, the saturation of {Bn(., qn)} when n → ∞ and convergence rate of Bn(f,q;x) when f ∈ C^n-1 [0, 1], q → ∞ are also presented. 展开更多
关键词 q-Bernstein operator convergence rate saturation of positive lienar operator iterates
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Definition of spatial positions within foraging Greater White-fronted Geese flocks from an individual's perspective:Cost-benefit dynamics change with the distance to flock edge
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作者 Mengzhen Wang Wenwen Chen +1 位作者 Chunlin Li Jinming Zhao 《Avian Research》 SCIE CSCD 2022年第4期454-460,共7页
The costs and benefits of group living are not evenly distributed among individuals that occupy different spatial positions within a group(central or peripheral).However,the definitions of central and peripheral posit... The costs and benefits of group living are not evenly distributed among individuals that occupy different spatial positions within a group(central or peripheral).However,the definitions of central and peripheral positions may artificially mask the true dynamics of cost and benefit of individuals.Using wintering foraging Greater Whitefronted Geese(Anser albifrons)flocks as our study system,we measured individual spatial position within a flock as distance to the flock edge.First,we tested the effects of distance to edge on the antipredation cost and foraging benefit of individual goose using generalized linear mixed models(GLMMs).Flock size and number of neighbors and their interactions with distance to edge were included as fixed effects in GLMMs.Then we used piecewise regression to determine the threshold value of distance to edge to classify central and peripheral individuals.Our results indicated distance to edge significantly affected percent of time spent on vigilance(vigilance time),percent of time spent on foraging(foraging time)and intake rate(pecks/min),whereas other factors had no effects.We found that the critical distance that predicted changes in behavior was around 2.5 m.Birds 2.5 m or less from the edge of the group were more vigilant,and had less efficient foraging than more central individuals.Behavioral differences between central and peripheral individuals were more easily detected when the birds were classified by the method introduced in this study than by the traditional minimum convex polygon method.Our research provides researchers a dichotomous classification scheme that places individuals into peripheral and central positions from an individual's perspective. 展开更多
关键词 Distance to edge Foraging time Intake rate Spatial position within a group Vigilance time
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SARS-CoV-2 infection rates after different vaccination schemes:An online survey in Turkey
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作者 Oya Baydar Toprak Sennur Ozen +4 位作者 Berker Ozturk Burcu Ozturk Ebru Ozturk Mehmet Kitapci Nurdan Kokturk 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2022年第4期171-178,共8页
Objective:To identify effects of various nationwide vaccination protocols on the evolution of new SARS-CoV-2 infections among adult population and to evaluate the safety of mRNA(BioNTech/Pfizer)vaccine.Methods:Totally... Objective:To identify effects of various nationwide vaccination protocols on the evolution of new SARS-CoV-2 infections among adult population and to evaluate the safety of mRNA(BioNTech/Pfizer)vaccine.Methods:Totally 10735 adult volunteers that received at least one dose of BioNTech/Pfizer or triple doses of CoronaVac participated in this cross-sectional-online survey between 1 and 10 September 2021.The information was collected covering a 5-month period from April 2021 to September 2021.Information about people who were vaccinated with only single and double dose CoronaVac were not included in this study.Results:At least one side effect after single and double dose of BioNTech/Pfizer and triple doses of CoronaVac were observed in 42.1%,42.5%and 10.9%,respectively.The most common side effects were shoulder/arm pain,weakness/fatigue,muscle/joint pain and headache.The side effects were the most frequent in single BioNTech/Pfizer,while it was the least in triple CoronaVac.The rate of positive PCR tests before vaccination was 17.6%,and decreased to 3.0%after vaccination.The rates of positive SARS CoV-2-PCR were 18.8%,3.5%,3.1%,0.5%and 4.6%in single BioNTech/Pfizer,double BioNTech/Pfizer,double CoronaVac+single BioNTech/Pfizer,double CoronaVac+double BioNTech/Pfizer and triple CoronaVac,respectively.While 1.8%of PCR positive COVID-19 cases needed intensive unit care in the pre-vaccination period,intensive care unit was required in 0%,1.5%,2.4%,0%and 4.2%after single BioNTech/Pfizer,double BioNTech/Pfizer,double CoronaVac+single BioNTech/Pfizer,double CoronaVac+double BioNTech/Pfizer and triple CoronaVac,respectively.Reinfection rate after vaccination was 0.4%.Conclusions:The rarity of COVID-19 infection after vaccination suggests that efficacy of vaccines is maintained.On the other hand,the data underscore the critical importance of continued public health mitigation. 展开更多
关键词 mRNA vaccine COVID-19 SARS-CoV-2 Vaccine schemes REINFECTION positivity rate after vaccination
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GPS Vector Tracking Receivers with Rate Detector for Integrity Monitoring
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作者 Dah-Jing Jwo Ming-Hsuan Lee 《Computers, Materials & Continua》 SCIE EI 2021年第11期2387-2403,共17页
In this paper,the integrity monitoring algorithm based on a Kalman filter(KF)based rate detector is employed in the vector tracking loop(VTL)of the Global Positioning System(GPS)receiver.In the VTL approach,the extend... In this paper,the integrity monitoring algorithm based on a Kalman filter(KF)based rate detector is employed in the vector tracking loop(VTL)of the Global Positioning System(GPS)receiver.In the VTL approach,the extended Kalman filter(EKF)simultaneously tracks the received signals and estimates the receiver’s position,velocity,etc.In contrast to the scalar tracking loop(STL)that uses the independent parallel tracking loop approach,the VTL technique uses the correlation of each satellite signal and user dynamics and thus reduces the risk of loss lock of signals.Although the VTL scheme provides several important advantages,the failure of tracking in one channel may affect the entire system and lead to loss of lock on all satellites.The integrity monitoring algorithm can be adopted for robustness enhancement.In general,the standard integrity monitoring algorithm can timely detect the step type erroneous signals.However,in the presence of ramp type slowly growing erroneous signals,detection of such type of error takes much more time since the error cannot be detected until the cumulative exceeds the specified threshold.The integrity monitoring based on the rate detector possesses good potential for resolving such problem.The test statistic based on the pseudorange residual in association with the EKF is applied for determination of whether the test statistic exceeds the allowable threshold values.The fault detection and exclusion(FDE)mechanism can then be employed to exclude the hazardous erroneous signals for the abnormal satellites to assure normal operation of GPS receivers.Feasibility of the integrity monitoring algorithm based on the EKF based rate detector will be demonstrated.Performance assessment and evaluation will be presented. 展开更多
关键词 Global positioning system vector tracking loop integrity monitoring rate detector slowly growing errors
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Relationship of Milk Line Position with Grain Weight and Mechanized Harvest of Summer Corn
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作者 Yan MENG Xiyun SUN +2 位作者 Fanyu MENG Guangyuan LU Qianqian HOU 《Agricultural Science & Technology》 CAS 2017年第10期1841-1844,1851,共5页
To investigate the relationship of milk line position with grain weight and mechanized harvest of summer corn in Huang-Huai-Hai Region, 8 varieties (A, B, C, D, E, F, G, H) with large planting areas were selected to... To investigate the relationship of milk line position with grain weight and mechanized harvest of summer corn in Huang-Huai-Hai Region, 8 varieties (A, B, C, D, E, F, G, H) with large planting areas were selected to measure the grain filling rate, 100-grain weight, water content and milk line position, and the correlation was analyzed. Results showed that when the milk line position was 90%, the grain filling of all the 8 varieties finished and 100-grain weight reached the highest value, which was 43.02 g. The grain filling time was in positive correlation with 100-grain weight. However, when the milk line position completely disappeared, the 100-grain weight was reduced by 8.66% at most. There was no significant difference during the periods of grain weight rising, but in the periods of grain weight falling, the traits of D, E, H were significantly different with the other varieties, and water loss rate of C and A showed significant difference with the other six varieties. The water content of grain was negatively correlated with milk line position. When the milk line percentage was 90% , the grain water content was less than 30% . The key factor influencing the mechanized harvest of summer corn is harvesting time, rather than the varieties. Moreover, milk-line position of 90% is the best time for harvest; if the harvest is too late, the yield will be reduced with varying degrees. 展开更多
关键词 MAIZE Grain filling rate 100-grain weight Milk line position Mechanized harvest
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