Compared with the one-dimensional trajectory correction technology which adjusts longitudinal range, not only does the two-dimensional trajectory correction technology adjust the force in velocity direction, but also ...Compared with the one-dimensional trajectory correction technology which adjusts longitudinal range, not only does the two-dimensional trajectory correction technology adjust the force in velocity direction, but also need to modulate the lateral force or trajectory (perpendicular to the vertical plane of fire direction). Therefore, the structure of control cabin of two-dimensional trajectory correction projectile (TDTCP) is more complicated than that of one-dimensional trajectory correction projectile (ODTCP). To simplify the structure of control cabin of TDTCP and reduce the cost, a scheme of adding a damping disk to the control cabin of ODTCP has been developed recently. The damping disk is unfolded at the right moment during its flight to change the ballistic drift of spin stabilized projectile. For this technical scheme of TDTCP, a fast and accurate impact point prediction method based on extended Kalman filter is presented. An approximate formula for predicting the ballistic drift and trajectory correction quantity is deduced. And the lateral correction capability for different fire angles and its influencing factors are analyzed. All the work is valuable for further research.展开更多
In this paper we study the proximal point algorithm (PPA) based predictioncorrection (PC) methods for monotone variational inequalities. Each iteration of these methods consists of a prediction and a correction. The p...In this paper we study the proximal point algorithm (PPA) based predictioncorrection (PC) methods for monotone variational inequalities. Each iteration of these methods consists of a prediction and a correction. The predictors are produced by inexact PPA steps. The new iterates are then updated by a correction using the PPA formula. We present two profit functions which serve two purposes: First we show that the profit functions are tight lower bounds of the improvements obtained in each iteration. Based on this conclusion we obtain the convergence inexactness restrictions for the prediction step. Second we show that the profit functions are quadratically dependent upon the step lengths, thus the optimal step lengths are obtained in the correction step. In the last part of the paper we compare the strengths of different methods based on their inexactness restrictions.展开更多
Langevin simulation of the particles multi-passing over the saddle point is proposed to calculate thermal fission rate.Due to finite friction and the corresponding thermal flutuation,a backstreaming exists in the proc...Langevin simulation of the particles multi-passing over the saddle point is proposed to calculate thermal fission rate.Due to finite friction and the corresponding thermal flutuation,a backstreaming exists in the process of the particle descent from the saddle to the scissio.This leads to that the diffusion behind the saddle point has influence upon the stationary flow across the saddle point.A dynamical correction factor,as a ratio of the flows of multi-and firstoverpassing the saddle point,is evaluated analytically.The results show that the fission rate calculated by the particles multi-passing over the saddle point is lower than the one calculated by the particle firstly passing over the saddle point,and the fomer approaches the results at the scission point.展开更多
In single-frequency precise-point positioning of a satellite,ionosphere delay is one of the most important factors impacting the accuracy. Because of the instability of the ionosphere and uncertainty of its physical p...In single-frequency precise-point positioning of a satellite,ionosphere delay is one of the most important factors impacting the accuracy. Because of the instability of the ionosphere and uncertainty of its physical properties, the positioning accuracy is seriously limited when using a precision-limited model for correction. In order to reduce the error, we propose to introduce some ionosphere parameter for real-time ionosphere-delay estimation by applying various mapping functions. Through calculation with data from the IGS( International GPS Service) tracking station and comparison among results of using several different models and mapping functions, the feasibility and effectiveness of the new method are verified.展开更多
This article focuses on the performance analysis of both real-time and post-mission kinematic precise point positioning(PPP)in challenging marine environments.For this purpose,a real dynamic experiment lasting 6 h was...This article focuses on the performance analysis of both real-time and post-mission kinematic precise point positioning(PPP)in challenging marine environments.For this purpose,a real dynamic experiment lasting 6 h was carried out on a lake dam in?orum City of Turkey.While the kinematic test was continuing,the real-time PPP coordinates were obtained for each measurement epoch with a commercial real-time PPP(RT-PPP)service,namely the Trimble Center Point RTX.Then the post-mission PPP(PM-PPP)coordinates were calculated by using Multi-GNSS data and the Multi-GNSS Experiment(MGEX)precise products.The kinematic RT-PPP and PM-PPP results showed that the PPP coordinates were consistent with the relative solution at centimetre and decimetre level in horizontal and height components,respectively.This study implies that PPP technique is a powerful tool for highly accurate positioning in both real-time and post-mission modes,even for dynamic applications in harsh environments.展开更多
A computer model for studying the mechanical properties of point - bonded nonwovens is established. The simulation tensile curve of a nonwoven fabric may be obtained based on relaxation procedure when the mechanical p...A computer model for studying the mechanical properties of point - bonded nonwovens is established. The simulation tensile curve of a nonwoven fabric may be obtained based on relaxation procedure when the mechanical properties of fibers, the arrangement of bond points in the fibrous web and specimen size are inputted into the computer. Relaxation method and relevant algorithms of computer simulation are described in detail. The validity of the model is also demonstrated.展开更多
By means of programs GTMPAC based- on generalized triangle method,analysis and synthesis of mechanism design in accordance with absolutely graphicalmethod( absolutely germetrical method) are developed.In this paper,we...By means of programs GTMPAC based- on generalized triangle method,analysis and synthesis of mechanism design in accordance with absolutely graphicalmethod( absolutely germetrical method) are developed.In this paper,we make aspecial study about centering- point curve and circling- point curve and couplercurves based on Ball’s points.展开更多
In this paper, first we introduce notions of (α, Ψ)-contractive and (α)-admissible for a pair of map and prove a coupled coincidence point theorem for compatible mappings using these notions. Our work extends and g...In this paper, first we introduce notions of (α, Ψ)-contractive and (α)-admissible for a pair of map and prove a coupled coincidence point theorem for compatible mappings using these notions. Our work extends and generalizes the results of Mursaleen et al. [1]. At the end, we will provide an example in support of our result.展开更多
This article focuses on analyzing the excerpt from The Corrections written by Jonathan Franzen.The analysis shed light on the participating characters(Chip and his father,Alfred)by exploring the point of view of the a...This article focuses on analyzing the excerpt from The Corrections written by Jonathan Franzen.The analysis shed light on the participating characters(Chip and his father,Alfred)by exploring the point of view of the author and on the peculiarities of their family relationship as well as the emotional change of Chip.展开更多
<strong>Objective:</strong> The purpose of this work was to determine the epidemiological, clinical and evolutionary aspects of the pulmonary embolism of the young person in the cardiology department of th...<strong>Objective:</strong> The purpose of this work was to determine the epidemiological, clinical and evolutionary aspects of the pulmonary embolism of the young person in the cardiology department of the University Hospital Center (CHU) Point G in Bamako-Mali. <strong>Methodology:</strong> This was an analytical study from January 01, 2018 to December 31, 2018 in the CHU Point G cardiology department, including all patients hospitalized during this period. <strong>Results:</strong> Of 1379 hospitalized patients, 19 patients were concerned by pulmonary embolism of the young person. The prevalence of pulmonary embolism of the young person was 1.37%. The most affected age group was 21 - 30 (47.4%) of patients. The predominance was female (89.47%) with a gender ratio of 0.11 in favour of women. The average age in the series was 29.79 years with extremes of 16 years and 40 years. Factors predisposing to pulmonary embolism were dominated by peri partum, cardiomyopathy and obesity with 47.3%, 31.57% and 21.1%, respectively. The dominant signs were chest pain and dyspnea in 94.7% and 89.5% of cases respectively. Pulmonary embolism was unlikely in 60.52% according to the Geneva and Wells score simplified. At the thoracic angioscanner, the embolism was bilateral in 52.6% of cases and distal in 36.8% of patients;in 10 patients who performed cardiac ultrasound, pulmonary arterial hypertension (70%), dilation of the right ventricle (20%) and left ventricular dilation (40%). Hyper leucocytosis (47.4%), anemia and low prothrombin rate (TP) (22.2%) were the most found biological abnormalities. More than 2/3 (68.5%) our patients had an intermediate mortality risk according to the PESI (Pulmonary Embolism Severity Index) score. The average hospital stay was 10 days. Hospital mortality was 10.5%. <strong>Conclusion:</strong> The pulmonary embolism of the young person is a frequent, serious and multifactorial pathology and the female sex is most affected especially during peri partum periods, hence the need for preventive measures. Clinical signs are not specific and based on the assessment of clinical probability. Pulmonary angioscanner remains the confirmation review in our context.展开更多
We apply a Cross-Correlation (CC) method developed previously for detecting gamma-ray point sources to the WMAP first year data by using the Point-Spread Function of WMAP and obtain a full sky CC coefficient map. We...We apply a Cross-Correlation (CC) method developed previously for detecting gamma-ray point sources to the WMAP first year data by using the Point-Spread Function of WMAP and obtain a full sky CC coefficient map. We find that the CC method is a powerful tool to examine the WMAP foreground residuals which can be further cleaned accord- ingly. Evident foreground signals are found in the WMAP foreground cleaned maps and the Tegmark cleaned map. In this process 101 point sources are detected, and 26 of them are new sources additional to the originally listed WMAP 208 sources. We estimate the flux of these new sources and verify them by another method. As a result, a revised mask file based on the WMAP first year data is produced by including these new sources.展开更多
CAS 132-2006 formulation background and work courses
Flat panel display technology is maturing alongside the development of science and technology. The prices of flat panel display TV sets are becoming lower ... CAS 132-2006 formulation background and work courses
Flat panel display technology is maturing alongside the development of science and technology. The prices of flat panel display TV sets are becoming lower and lower. Flat panel display TV sets have begun entering the mainstream and are now the first choice of some consumers when making new TV purchases.Display TV Set Installation Service Point Explanation and AnalysisRepair, Retreat and Change Duty Stipulations. Peculiar use conditions, usage environments, and the practical circumstances of user consumption service requirements, etc., were also taken into account on the basis of extensive investigation, testing, and verification.……展开更多
文摘Compared with the one-dimensional trajectory correction technology which adjusts longitudinal range, not only does the two-dimensional trajectory correction technology adjust the force in velocity direction, but also need to modulate the lateral force or trajectory (perpendicular to the vertical plane of fire direction). Therefore, the structure of control cabin of two-dimensional trajectory correction projectile (TDTCP) is more complicated than that of one-dimensional trajectory correction projectile (ODTCP). To simplify the structure of control cabin of TDTCP and reduce the cost, a scheme of adding a damping disk to the control cabin of ODTCP has been developed recently. The damping disk is unfolded at the right moment during its flight to change the ballistic drift of spin stabilized projectile. For this technical scheme of TDTCP, a fast and accurate impact point prediction method based on extended Kalman filter is presented. An approximate formula for predicting the ballistic drift and trajectory correction quantity is deduced. And the lateral correction capability for different fire angles and its influencing factors are analyzed. All the work is valuable for further research.
基金The author was supported by NSFC Grant 10271054MOEC grant 20020284027 and Jiangsur NSF grant BK20002075.
文摘In this paper we study the proximal point algorithm (PPA) based predictioncorrection (PC) methods for monotone variational inequalities. Each iteration of these methods consists of a prediction and a correction. The predictors are produced by inexact PPA steps. The new iterates are then updated by a correction using the PPA formula. We present two profit functions which serve two purposes: First we show that the profit functions are tight lower bounds of the improvements obtained in each iteration. Based on this conclusion we obtain the convergence inexactness restrictions for the prediction step. Second we show that the profit functions are quadratically dependent upon the step lengths, thus the optimal step lengths are obtained in the correction step. In the last part of the paper we compare the strengths of different methods based on their inexactness restrictions.
文摘电离层延迟可严重制约单频接收机的定位精度.基于此,本文介绍了四种单频接收机常用的电离层延迟改正方法,包括广播电离层改正模型(策略1),顾及太阳位置的变化全球电离层格网产品(Global Ionosphere Map,GIM)时间旋转内插(策略2),GIM投影函数改正(策略3)和半合改正模型(策略4).同时,选择不同太阳活动期,不同纬度的测站验证不同电离层改正方法的单频精密单点定位(single-frequency point positioning,SF-PPP)定位结果偏差.经过对比分析,得到如下结论:1)总体来说,半合改正模型得到的定位效果最佳,其次是使用GIM产品对电离层延迟进行改正,最后是广播电离层模型;2)在不同太阳活动跃期,不同策略在低纬度测站的定位偏差最大,其次是高纬度测站,中纬度测站的定位偏差最小;3)策略2和策略3在不同太阳活动期不同纬度测站的水平定位平差约0.150 m,三维定位偏差约0.700 m;策略4在不同太阳活动期不同纬度测站的水平定位偏差为0.100 m,三维定位偏差为0.500 m.
基金The project supported by National Natural Science Foundation of China under Grant Nos.10075007 and 10235020
文摘Langevin simulation of the particles multi-passing over the saddle point is proposed to calculate thermal fission rate.Due to finite friction and the corresponding thermal flutuation,a backstreaming exists in the process of the particle descent from the saddle to the scissio.This leads to that the diffusion behind the saddle point has influence upon the stationary flow across the saddle point.A dynamical correction factor,as a ratio of the flows of multi-and firstoverpassing the saddle point,is evaluated analytically.The results show that the fission rate calculated by the particles multi-passing over the saddle point is lower than the one calculated by the particle firstly passing over the saddle point,and the fomer approaches the results at the scission point.
基金supported by the National Natural Science Foundation of China(40902081,40774001,40841021)
文摘In single-frequency precise-point positioning of a satellite,ionosphere delay is one of the most important factors impacting the accuracy. Because of the instability of the ionosphere and uncertainty of its physical properties, the positioning accuracy is seriously limited when using a precision-limited model for correction. In order to reduce the error, we propose to introduce some ionosphere parameter for real-time ionosphere-delay estimation by applying various mapping functions. Through calculation with data from the IGS( International GPS Service) tracking station and comparison among results of using several different models and mapping functions, the feasibility and effectiveness of the new method are verified.
文摘This article focuses on the performance analysis of both real-time and post-mission kinematic precise point positioning(PPP)in challenging marine environments.For this purpose,a real dynamic experiment lasting 6 h was carried out on a lake dam in?orum City of Turkey.While the kinematic test was continuing,the real-time PPP coordinates were obtained for each measurement epoch with a commercial real-time PPP(RT-PPP)service,namely the Trimble Center Point RTX.Then the post-mission PPP(PM-PPP)coordinates were calculated by using Multi-GNSS data and the Multi-GNSS Experiment(MGEX)precise products.The kinematic RT-PPP and PM-PPP results showed that the PPP coordinates were consistent with the relative solution at centimetre and decimetre level in horizontal and height components,respectively.This study implies that PPP technique is a powerful tool for highly accurate positioning in both real-time and post-mission modes,even for dynamic applications in harsh environments.
文摘A computer model for studying the mechanical properties of point - bonded nonwovens is established. The simulation tensile curve of a nonwoven fabric may be obtained based on relaxation procedure when the mechanical properties of fibers, the arrangement of bond points in the fibrous web and specimen size are inputted into the computer. Relaxation method and relevant algorithms of computer simulation are described in detail. The validity of the model is also demonstrated.
文摘By means of programs GTMPAC based- on generalized triangle method,analysis and synthesis of mechanism design in accordance with absolutely graphicalmethod( absolutely germetrical method) are developed.In this paper,we make aspecial study about centering- point curve and circling- point curve and couplercurves based on Ball’s points.
文摘In this paper, first we introduce notions of (α, Ψ)-contractive and (α)-admissible for a pair of map and prove a coupled coincidence point theorem for compatible mappings using these notions. Our work extends and generalizes the results of Mursaleen et al. [1]. At the end, we will provide an example in support of our result.
文摘This article focuses on analyzing the excerpt from The Corrections written by Jonathan Franzen.The analysis shed light on the participating characters(Chip and his father,Alfred)by exploring the point of view of the author and on the peculiarities of their family relationship as well as the emotional change of Chip.
文摘<strong>Objective:</strong> The purpose of this work was to determine the epidemiological, clinical and evolutionary aspects of the pulmonary embolism of the young person in the cardiology department of the University Hospital Center (CHU) Point G in Bamako-Mali. <strong>Methodology:</strong> This was an analytical study from January 01, 2018 to December 31, 2018 in the CHU Point G cardiology department, including all patients hospitalized during this period. <strong>Results:</strong> Of 1379 hospitalized patients, 19 patients were concerned by pulmonary embolism of the young person. The prevalence of pulmonary embolism of the young person was 1.37%. The most affected age group was 21 - 30 (47.4%) of patients. The predominance was female (89.47%) with a gender ratio of 0.11 in favour of women. The average age in the series was 29.79 years with extremes of 16 years and 40 years. Factors predisposing to pulmonary embolism were dominated by peri partum, cardiomyopathy and obesity with 47.3%, 31.57% and 21.1%, respectively. The dominant signs were chest pain and dyspnea in 94.7% and 89.5% of cases respectively. Pulmonary embolism was unlikely in 60.52% according to the Geneva and Wells score simplified. At the thoracic angioscanner, the embolism was bilateral in 52.6% of cases and distal in 36.8% of patients;in 10 patients who performed cardiac ultrasound, pulmonary arterial hypertension (70%), dilation of the right ventricle (20%) and left ventricular dilation (40%). Hyper leucocytosis (47.4%), anemia and low prothrombin rate (TP) (22.2%) were the most found biological abnormalities. More than 2/3 (68.5%) our patients had an intermediate mortality risk according to the PESI (Pulmonary Embolism Severity Index) score. The average hospital stay was 10 days. Hospital mortality was 10.5%. <strong>Conclusion:</strong> The pulmonary embolism of the young person is a frequent, serious and multifactorial pathology and the female sex is most affected especially during peri partum periods, hence the need for preventive measures. Clinical signs are not specific and based on the assessment of clinical probability. Pulmonary angioscanner remains the confirmation review in our context.
基金Supported by the National Natural Science Foundation of China.
文摘We apply a Cross-Correlation (CC) method developed previously for detecting gamma-ray point sources to the WMAP first year data by using the Point-Spread Function of WMAP and obtain a full sky CC coefficient map. We find that the CC method is a powerful tool to examine the WMAP foreground residuals which can be further cleaned accord- ingly. Evident foreground signals are found in the WMAP foreground cleaned maps and the Tegmark cleaned map. In this process 101 point sources are detected, and 26 of them are new sources additional to the originally listed WMAP 208 sources. We estimate the flux of these new sources and verify them by another method. As a result, a revised mask file based on the WMAP first year data is produced by including these new sources.
文摘 CAS 132-2006 formulation background and work courses
Flat panel display technology is maturing alongside the development of science and technology. The prices of flat panel display TV sets are becoming lower and lower. Flat panel display TV sets have begun entering the mainstream and are now the first choice of some consumers when making new TV purchases.Display TV Set Installation Service Point Explanation and AnalysisRepair, Retreat and Change Duty Stipulations. Peculiar use conditions, usage environments, and the practical circumstances of user consumption service requirements, etc., were also taken into account on the basis of extensive investigation, testing, and verification.……