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Different positive end expiratory pressure and tidal volume controls on lung protection and inflammatory factors during surgical anesthesia 被引量:2
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作者 Yu Wang Yi Yang +5 位作者 Ding-Mu Wang Jie Li Quan-Tang Bao Bei-Bei Wang Shu-Jun Zhu Lu Zou 《World Journal of Clinical Cases》 SCIE 2022年第33期12146-12155,共10页
BACKGROUND Mechanical ventilation can lead to the severe impairment of the metabolic pathway of alveolar surfactants,inactivating alveolar surfactants and significantly reducing lung-chest compliance.The cardiopulmona... BACKGROUND Mechanical ventilation can lead to the severe impairment of the metabolic pathway of alveolar surfactants,inactivating alveolar surfactants and significantly reducing lung-chest compliance.The cardiopulmonary function of elderly patients usually reduced to a certain extent,and there are lung complications after surgical anesthesia,just like lung barotrauma caused by mechanical ventilation,atelectasis and postoperative hypoxemia.AIM To investigate the effects of different positive end expiratory pressures(PEEPs)and tidal volumes(VTs)on respiratory function,the degree of the inflammatory response and hemodynamic indexes in patients undergoing surgery under general anesthesia.METHODS A total of 120 patients undergoing surgery for gastric or colon cancer under general anesthesia in Xinghua People's Hospital from January 2017 to January 2021 were randomly divided into Group A and Group B,with 60 cases in each group.The ventilation mode in Group A was VT(6.0 mL/kg)+PEEP(5.0 cmH_(2)O),while that in Group B was VT(6.0 mL/kg)+PEEP(8.0 cmH_(2)O).Blood gas parameters,respiratory mechanical parameters,inflammatory response indicators,hemodynamic indicators and related complications were compared between the two groups.RESULTS There were no significant differences in PaCO_(2),PaO_(2),oxygen or the examined indexes at T0 between group A and group B(P>0.05).The measured PaO_(2) value of patients in group A at T3 was higher than that in group B,and the difference was significant(P<0.05).There were no significant differences in peak airway pressure(P_(peak)),mean airway pressure or dynamic pulmonary compliance(Cdyn)at T0 between group A and group B(P>0.05).The measured P_(peak) value of patients in group A at T1 was higher than that in group B,and the difference was significant(P<0.05).The measured Cdyn value at T1 and T2 was greater than that in group B(P<0.05).Before surgery,there were no significant differences in tumor necrosis factor-α(TNF-α),interleukin(IL)-6 or IL-10 between group A and group B(P>0.05).After 4 h,the measured values of TNF-αand IL-6 in group A were lower than those in group B,and the differences were significant(P<0.05).The IL-10 Level in group A was higher than that in group B(P<0.05).At T0,there were no significant differences in cardiac output,cardiac index(CI),stroke volume index(SVI)or mean arterial pressure between group A and group B(P>0.05).The measured values of CI and SVI at T2 in patients in group A were higher than those in group B,and the differences were significant(P<0.05).CONCLUSION For patients undergoing surgery for gastric or colon cancer under general anesthesia,the VT(6.0 mL/kg)+PEEP(5.0 cmH_(2)O)regimen was more effective than the VT(6.0 mL/kg)+PEEP(8.0 cmH_(2)O)regimen in protecting the lung function and ventilatory function of patients,and it had better effects on maintaining hemodynamic stability and reducing inflammatory reactions. 展开更多
关键词 general anesthesia positive end expiratory pressure Tidal volume Respiratory function Inflammatory reactions HEMODYNAMICS
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Evaluation of Pressure of Arterial Oxygen by Age in Supine Position during General Anesthesia
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作者 Kenichi Satoh Ayako Ohashi +3 位作者 Miho Kumagai Masahito Sato Akiyoshi Kuji Shigeharu Joh 《Open Journal of Anesthesiology》 2015年第3期37-42,共6页
Background: The concentration of supplemental O2 should be measured during general anesthesia to determine whether patients’ pressure of arterial oxygen (PaO2) is correct. Nevertheless, we do not know standard value ... Background: The concentration of supplemental O2 should be measured during general anesthesia to determine whether patients’ pressure of arterial oxygen (PaO2) is correct. Nevertheless, we do not know standard value of PaO2 by age in supine position during general anesthesia. In this study, we evaluated the PaO2 by age at 33% or 40% O2 concentration. Materials and Methods: We retrospectively reviewed the anesthetic charts of 660 patients who were received general anesthesia from January 2001 to December 2013. Patients were divided into two groups by concentration of fraction of inspiratory oxygen: group at 33% or 40%. Second, patients aged 16 - 85 years were classified into 7 groups by age with each group covering one decade. Results: The PaO2 was 185.1 ± 19.2 mmHg (33%) and 209.8 ± 19.8 mmHg (40%) at age 16 - 25 years, 178.7 ± 23.6 mmHg (33%) and 202.7 ± 26.0 mmHg (40%) at age 26 - 35 years, 165.8 ± 30.6 mmHg (33%) and 188.9 ± 22.2 (40%) mmHg at age 36 - 45 years, 154.1 ± 22.8 mmHg (33%) and 181.8 ± 19.2 (40%) mmHg at age 46 - 55 years, 153.7 ± 21.7 mmHg (33%) and 177.5 ± 18.1 mmHg (40%) at age 56 - 65 years, 152.2 ± 24.5 mmHg and 171.0 ± 22.1 mmHg at age 66 - 75 years, and 154.6 ± 24.3 mmHg and 174.1 ± 20.2 mmHg at age 76 - 85 years. Conclusion: The PaO2 tended to decrease with age at both 33% and 40% O2 concentration. 展开更多
关键词 PRESSURE of ARTERIAL OXYGEN SUPINE positION Age general ANESTHESIA
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Existence and Uniqueness of Positive Periodic Solutions for First-order Functional Differential Equations
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作者 HAN Qian-qian ZHAI Cheng-bo 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第3期454-461,共8页
In this paper, we prove the existence and uniqueness of positive periodic solutions for first-order functional differential equation y'(t) = α(t)y(t) + f(t, y(t -τ-(t))) + g(t)by using two fixed poi... In this paper, we prove the existence and uniqueness of positive periodic solutions for first-order functional differential equation y'(t) = α(t)y(t) + f(t, y(t -τ-(t))) + g(t)by using two fixed point theorems of general α-concave operators and homogeneous operators in ordered Banach spaces. 展开更多
关键词 functional differential equation existence and uniqueness positive periodics olution~ general s-concave operator homogeneous operator
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Evaluation of Partial Pressure of Arterial Oxygen in Obese Patients in Supine Position during General Anesthesia
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作者 Kenichi Satoh Mami Chikuda +3 位作者 Ayako Ohashi Miho Kumagai Akiyoshi Kuji Shigeharu Joh 《Open Journal of Anesthesiology》 2015年第5期85-92,共8页
Background: Anesthetists should measure the concentration of supplemental oxygen to determine whether patients’ partial pressure of arterial oxygen (PaO2) is correct during general anesthesia. However, the standard P... Background: Anesthetists should measure the concentration of supplemental oxygen to determine whether patients’ partial pressure of arterial oxygen (PaO2) is correct during general anesthesia. However, the standard PaO2 value in obese patients in the supine position is unknown. We evaluated the PaO2 with respect to the Broca-Katsura obesity index. Materials and Methods: From January 2001 to December 2013, we evaluated 472 patients aged ≥16 years old that underwent general anesthesia in the supine position. The anesthetic charts of 472 patients with an American Society of Anesthesiologists physical status of I or II were retrospectively reviewed to investigate the PaO2. Results: In patients aged 16 to 2 was 165.7 ± 25.6 mmHg at a Broca-Katsura index of 2 was 152.1 ± 23.8 mmHg at a Broca-Katsura index of 2 tended to decrease with age from 16 to 2 tended to decrease with age from 16 to <65 years at a Broca-Katsura index of 20% to <40%. 展开更多
关键词 ARTERIAL Partial Pressure of OXYGEN Broca-Katsura Index general ANESTHESIA OBESITY SUPINE position
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The Dynamic Plateau Monsoon Index and Its Association with General Circulation Anomalies 被引量:18
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作者 荀学义 胡泽勇 马耀明 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2012年第6期1249-1263,共15页
Based on monthly ECMWF reanalysis-Interim (ERA-Interim) reanalysis data, along with monthly precipitation and temperature data, the Dynamic Plateau Monsoon Index (DPMI) is defined. The results of a contrast analys... Based on monthly ECMWF reanalysis-Interim (ERA-Interim) reanalysis data, along with monthly precipitation and temperature data, the Dynamic Plateau Monsoon Index (DPMI) is defined. The results of a contrast analysis of the DPMI versus the Traditional Plateau Monsoon Index (TPMI) are described. The response of general circulation to northern Qinghai-Xizang Plateau summer monsoon anomalies and the correlation of the DPMI with general circulation anomalies are investigated. The results show that, the DPMI reflected meteorological elements better and depicted climate variation more accurately than the TPMI. In years when the plateau summer monsoon is strong, the low over the plateau and the trough near the eastern coast of Asia are deeper and higher than normal over South China. This correlation corresponds to two anomalous cyclones over the plateau and the eastern coast of Asia and an anomalous anticyclone in South China. The plateau and its adjacent regions are affected by anomalous southwesterly winds that transport more moisture to South China and cause more precipitation. The lower reaches of the Yangtze River appear to receive more precipitation by means of the strong westerly water vapor flow transported from the "large triangle affecting the region". In years when the plateau summer monsoon is weak, these are opposite. The plateau monsoon is closely related to the intensity and position of the South Asian high, and the existence of a teleconnection pattern in the mid-upper levels suggests a possible linkage of the East Asian monsoon and the Indian monsoon to the plateau summer monsoon. 展开更多
关键词 Qinghai-Xizang Plateau Dynamic Plateau Monsoon Index center position general circulation
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Effect of Right Supine Tracheal Extubation on Respiratory Complications and Airway Pressure in the Waking Period of General Anesthesia in Pediatric Stomatology 被引量:1
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作者 Zhijun Xin Ning Wang +2 位作者 Huaizhou Wang# Changhui Li Tianfeng Wang 《Open Journal of Anesthesiology》 2021年第12期347-354,共8页
<b>Objective:</b> The purpose of this study was to investigate the effect of right supine endotracheal intubation on respiratory complications and airway pressure of general anesthesia, and to provide guid... <b>Objective:</b> The purpose of this study was to investigate the effect of right supine endotracheal intubation on respiratory complications and airway pressure of general anesthesia, and to provide guidance for clinical application. <b>Methods:</b> Seventy-two children who received oral treatment under general anesthesia from November 2020 to November 2021 in Yantai Stomatological Hospital were randomly divided into three groups, 24 cases in each group. All three groups of children entered the PACU after the surgery. The children in Group I were extubated in the supine position, the children in Group II were immediately changed to the right decubitus after extubation in the horizontal position, and the children in Group III were extubated in the right decubitus. HR, MAP and SpO<sub>2</sub> of T1 (the time point at the beginning of surgery), T2 (the time point at 1 hour after surgery), T3 (the time point after extubation), T4 (the time point at 1 minute after extubation), T5 (the time point at 3 minutes after extubation) in the three groups were observed, t1 (operation time) and t2 (the time of leaving the PACU) were recorded. The airway pressure (P1) in the recumbent position and the airway pressure (P2) in the right decubitus position before extubation were recorded in Group III. The number of sputum suction and complications after extubation were counted. <b>Results:</b> The t2 in Group III was shorter than that in Groups I and II, and the number of sputum suction in Group III was less than that in Groups I and II (P < 0.05). The HR at T3, T4 and T5 in Group III was lower than that in Group I, and the HR at T4 and T5 was lower than that in Group II (P < 0.05). There were significant differences in the incidence of respiratory complications among the three groups (P < 0.05). The incidence of asphyxia, bucking and glossocoma postoperative agitation in Group III was significantly lower than that in Group I, and the incidence of asphyxia and choking was lower than that in Group II (P < 0.05). The incidence of glossoptosis in Group II was significantly lower than that in Group I (P < 0.05). In Group III, the airway pressure P2 in the right decubitus position during endotracheal intubation was higher than that of P1 in the supine position during endotracheal intubation (P < 0.05). The 95% Confidence Interval (CI) of airway pressure difference was 1.416 - 1.834 cmH<sub>2</sub>O. <b>Conclusion:</b> For children undergoing intraoral therapy under general anesthesia, tracheal extubation in the right decubitus position can improve the circulation fluctuation before and after extubation, reducing the number of sputum suction and respiratory tract-related complications, and can shorten the departure time. The body position change during the tracheal intubation will slightly increase the airway pressure, but the supine position after extubation can better ensure the smooth spontaneous breathing of children, which can provide the reference for clinical application. 展开更多
关键词 Lateral Decubitus position Intraoral Therapy for Children general Anesthesia Respiratory Complications Airway Pressure
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SNWPM:A Siamese Network Based Wireless Positioning Model Resilient to Partial Base Stations Unavailable
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作者 Yasong Zhu Jiabao Wang +4 位作者 Yi Sun Bing Xu Peng Liu Zhisong Pan Wangdong Qi 《China Communications》 SCIE CSCD 2023年第9期20-33,共14页
Artificial intelligence(AI)models are promising to improve the accuracy of wireless positioning systems,particularly in indoor environments where unpredictable radio propagation channel is a great challenge.Although g... Artificial intelligence(AI)models are promising to improve the accuracy of wireless positioning systems,particularly in indoor environments where unpredictable radio propagation channel is a great challenge.Although great efforts have been made to explore the effectiveness of different AI models,it is still an open problem whether these models,trained with the data collected from all base stations(BSs),could work when some BSs are unavailable.In this paper,we make the first effort to enhance the generalization ability of AI wireless positioning model to adapt to the scenario where only partial BSs work.Particularly,a Siamese Network based Wireless Positioning Model(SNWPM)is proposed to predict the location of mobile user equipment from channel state information(CSI)collected from 5G BSs.Furthermore,a Feature Aware Attention Module(FAAM)is introduced to reinforce the capability of feature extraction from CSI data.Experiments are conducted on the 2022 Wireless Communication AI Competition(WAIC)dataset.The proposed SNWPM achieves decimeter-level positioning accuracy even if the data of partial BSs are unavailable.Compared with other AI models,the proposed SNWPM can reduce the positioning error by nearly 50%to more than 60%while using less parameters and lower computation resources. 展开更多
关键词 wireless positioning indoor positioning generalization ability AI positioning model ATTENTION
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Remote positioning system based on GPS/GPRS
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作者 李泽明 李锦明 杨燕姣 《Journal of Measurement Science and Instrumentation》 CAS 2013年第3期276-281,共6页
Considering the need of target positioning,a remote positioning system is designed based on global positioning system(GPS)and general packet radio service(GPRS);The data collection terminal is based on microcontroller... Considering the need of target positioning,a remote positioning system is designed based on global positioning system(GPS)and general packet radio service(GPRS);The data collection terminal is based on microcontroller unit(MCU)PIC24FV301.It uses GPRS network to create wireless link and transmits GPS source information which is collected by LEA-5H board to monitor center on the Internet.The monitor center obtains the target information through processing and analysis of the calculated data.Actual operation results indicate that the designed system has excellent performance and achieves the goal of the remote location. 展开更多
关键词 global positioning system (GPS) general packet radio service (GPRS) microcontroller unit (MCU) remote target positioningCLC number:TN927+.23 Document code:AArticle ID:1674-8042(2013)03-0276-06
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Integration system research and development for three-dimensional laser scanning information visualization in goaf 被引量:1
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作者 罗周全 黄俊杰 +2 位作者 罗贞焱 汪伟 秦亚光 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第7期1985-1994,共10页
An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, clo... An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, cloud data de-noising optimization, construction, display and operation of three-dimensional model, model editing, profile generation, calculation of goaf volume and roof area, Boolean calculation among models and interaction with the third party soft ware. Concerning this system with a concise interface, plentiful data input/output interfaces, it is featured with high integration, simple and convenient operations of applications. According to practice, in addition to being well-adapted, this system is favorably reliable and stable. 展开更多
关键词 GOAF laser scanning visualization integration system 1 Introduction The goaf formed through underground mining of mineral resources is one of the main disaster sources threatening mine safety production [1 2]. Effective implementation of goaf detection and accurate acquisition of its spatial characteristics including the three-dimensional morphology the spatial position as well as the actual boundary and volume are important basis to analyze predict and control disasters caused by goaf. In recent years three-dimensional laser scanning technology has been effectively applied in goaf detection [3 4]. Large quantities of point cloud data that are acquired for goaf by means of the three-dimensional laser scanning system are processed relying on relevant engineering software to generate a three-dimensional model for goaf. Then a general modeling analysis and processing instrument are introduced to perform subsequent three-dimensional analysis and calculation [5 6]. Moreover related development is also carried out in fields such as three-dimensional detection and visualization of hazardous goaf detection and analysis of unstable failures in goaf extraction boundary acquisition in stope visualized computation of damage index aided design for pillar recovery and three-dimensional detection
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A Second Main Theorem of Nevanlinna Theory for Closed Subschemes in Subgeneral Position 被引量:1
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作者 Guangsheng YU 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2022年第4期567-584,共18页
In this paper,by using Seshadri constants for subschemes,the author establishes a second main theorem of Nevanlinna theory for holomorphic curves intersecting closed subschemes in(weak)subgeneral position.As an applic... In this paper,by using Seshadri constants for subschemes,the author establishes a second main theorem of Nevanlinna theory for holomorphic curves intersecting closed subschemes in(weak)subgeneral position.As an application of his second main theorem,he obtain a Brody hyperbolicity result for the complement of nef effective divisors.He also give the corresponding Schmidt’s subspace theorem and arithmetic hyperbolicity result in Diophantine approximation. 展开更多
关键词 Second main theorem In general position Closed subscheme Seshadri constant Schmidt’s subspace theorem HYPERBOLICITY
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CRITERION OF POSITIVE DEFINITENESS OF MATRICES AND SOLUTION OF INVERSE PROBLEM FOR SYSTEM OF LINEAR EQUATIONS
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作者 郭忠 《Chinese Science Bulletin》 SCIE EI CAS 1989年第2期89-94,共6页
The class of symmetric definitely positive matrices is extremely important in the matrix theory. At present, positive definiteness of a symmetric matrix can be shown by determining the signs of its all ordered princip... The class of symmetric definitely positive matrices is extremely important in the matrix theory. At present, positive definiteness of a symmetric matrix can be shown by determining the signs of its all ordered principal minors or the signs 展开更多
关键词 cneralized positively definite MATRIX INVERSE problem general solution.
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EXISTENCE AND UNIQUENESS OF POSITIVE SOLUTIONS TO FRACTIONAL BOUNDARY VALUE PROBLEMS
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作者 Li Xu Chengbo Zhai 《Annals of Differential Equations》 2014年第3期352-358,共7页
In this paper, using fixed point theorems of general β-concave operators in ordered Banach space, we obtain the existence and uniqueness of positive solutions to a class of fractional boundary problem. In the end, an... In this paper, using fixed point theorems of general β-concave operators in ordered Banach space, we obtain the existence and uniqueness of positive solutions to a class of fractional boundary problem. In the end, an example is given to illustrate our main result. 展开更多
关键词 fractional order derivative positive solution general β-concave operator fractional boundary value problem
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On the ErdÖs Distance Conjecture in Geometry
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作者 Amir Jafari Amin Najafi Amin 《Open Journal of Discrete Mathematics》 2016年第3期109-160,共52页
Erd&#214;s asks if it is possible to have n points in general position in the plane (no three on a line or four on a circle) such that for every i (1≤i≤n-1 ) there is a distance determined by the points that occ... Erd&#214;s asks if it is possible to have n points in general position in the plane (no three on a line or four on a circle) such that for every i (1≤i≤n-1 ) there is a distance determined by the points that occur exactly i times. So far some examples have been discovered for 2≤n≤8 [1] [2]. A solution for the 8 point is provided by I. Palasti [3]. Here two other possible solutions for the 8 point case as well as all possible answers to 4 - 7 point cases are provided and finally a brief discussion on the generalization of the problem to higher dimensions is given. 展开更多
关键词 ErdÖs Distance Problem general position Graph Pattern Distance Distribution
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A two-step weighted least-squares method for joint estimation of source and sensor locations: A general framework 被引量:10
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作者 Ding WANG Jiexin YIN +2 位作者 Tao TANG Ruirui LIU Zhidong WU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第2期417-443,共27页
It is well known that the Two-step Weighted Least-Squares(TWLS) is a widely used method for source localization and sensor position refinement. For this reason, we propose a unified framework of the TWLS method for jo... It is well known that the Two-step Weighted Least-Squares(TWLS) is a widely used method for source localization and sensor position refinement. For this reason, we propose a unified framework of the TWLS method for joint estimation of multiple disjoint sources and sensor locations in this paper. Unlike some existing works, the presented method is based on more general measurement model, and therefore it can be applied to many different localization scenarios.Besides, it does not have the initialization and local convergence problem. The closed-form expression for the covariance matrix of the proposed TWLS estimator is also derived by exploiting the first-order perturbation analysis. Moreover, the estimation accuracy of the TWLS method is shown analytically to achieve the Cramér-Rao Bound(CRB) before the threshold effect takes place. The theoretical analysis is also performed in a common mathematical framework, rather than aiming at some specific signal metrics. Finally, two numerical experiments are performed to support the theoretical development in this paper. 展开更多
关键词 Cramér-Rao Bound(CRB) DISJOINT sources general framework Performance analysis Sensor position refinement SOURCE localization WEIGHTED LEAST-SQUARES
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A New Quasi-local Mass and Positivity
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作者 Xiao ZHANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2008年第6期881-890,共10页
A new definition of quasi-local mass is proposed and its positivity is proved under certain conditions.
关键词 general relativity quasi-local mass positIVITY
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STABILITY OF GENERALIZED JACKSON NETWORKS WITH INFINITE SUPPLY OF WORK
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作者 Yongjiang GUO 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2008年第2期283-295,共13页
A general Jackson network (GJN) with infinite supply of work is considered. By fluid limit model, the author finds that the Markov process describing the dynamics of the GJN with infinite supply of work is positive ... A general Jackson network (GJN) with infinite supply of work is considered. By fluid limit model, the author finds that the Markov process describing the dynamics of the GJN with infinite supply of work is positive Harris recurrent if the corresponding fluid model is stable. Furthermore, the author proves that the fluid model is stable if the usual traffic condition holds. 展开更多
关键词 Fluid limit model general Jackson network (GJN) infinite supply positive Harris recurrent stability.
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Finite sample breakdown point of Tukey's halfspace median 被引量:3
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作者 LIU XiaoHui ZUO YiJuna WANG QiHua 《Science China Mathematics》 SCIE CSCD 2017年第5期861-874,共14页
Tukey's halfspace median(HM), servicing as the multivariate counterpart of the univariate median,has been introduced and extensively studied in the literature. It is supposed and expected to preserve robustness pr... Tukey's halfspace median(HM), servicing as the multivariate counterpart of the univariate median,has been introduced and extensively studied in the literature. It is supposed and expected to preserve robustness property(the most outstanding property) of the univariate median. One of prevalent quantitative assessments of robustness is finite sample breakdown point(FSBP). Indeed, the FSBP of many multivariate medians have been identified, except for the most prevailing one—the Tukey's halfspace median. This paper presents a precise result on FSBP for Tukey's halfspace median. The result here depicts the complete prospect of the global robustness of HM in the finite sample practical scenario, revealing the dimension effect on the breakdown point robustness and complimenting the existing asymptotic breakdown point result. 展开更多
关键词 Tukey depth Tukey median breakdown point in general position
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A quasi-local mass for 2-spheres with negative Gauss curvature 被引量:3
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作者 ZHANG Xiao Institute of Mathematics, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100080, China 《Science China Mathematics》 SCIE 2008年第9期1644-1650,共7页
We extend our previous definition of quasi-local mass to 2-spheres whose Gauss curvature is negative, and prove its positivity.
关键词 general relativity quasi-local mass positIVITY 53C27 53C50 83C60
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A study on volunteer augmentation navigation technology 被引量:1
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作者 WU HaiTao 1,2,LU XiaoChun 1,2,ZOU DeCai 1,2 & HAN Tao 1,2 1 National Time Service Center,Chinese Academy of Sciences,Xi’an 710600,China 2 Key Laboratory of Precision Navigation and Timing Technology,Chinese Academy of Sciences,Xi’an 710600,China 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第6期1029-1034,共6页
Navigation augmentation technology is one of the most common methods to increase the continuity,reliability and integrity of the global satellite navigation system.The concept of volunteer augmentation navigation (VNA... Navigation augmentation technology is one of the most common methods to increase the continuity,reliability and integrity of the global satellite navigation system.The concept of volunteer augmentation navigation (VNA) is proposed and the elements and topological structure of VNA are also analyzed in this paper.The study focuses on the neural network model that volunteers and ordinary users use modern communication information network to exchange self-organizing information.The neural cell model of Volunteer Augmentation Navigation using shared information is built.Thus interactive general relative positioning is realized.Then basic theories and methods of volunteer augmentation navigation are formed on the basis of the above-mentioned study.This study of realization mechanism of volunteer augmentation technology helps to form a relatively integral architecture of volunteer augmentation navigation.A user self-service satellite navigation augmentation which combines information exchange and navigation services may strengthen the continuity,reliability and integrity of the navigation system.The volunteer augmentation navigation theory proposed in this paper improves the traditional satellite navigation application model and expands the connotation and denotation of satellite navigation augmentation methods. 展开更多
关键词 VOLUNTEER augmentation NAVIGATION self-organizing information exchange interactive general relative positioning
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BOUNDEDNESS OF A CLASS OF NONLINEAR SECONDORDER FUNCTIONAL DIFFERENTIAL EQUATIONS
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作者 冯祐和 《Chinese Science Bulletin》 SCIE EI CAS 1987年第15期1075-1077,共3页
In his article 'Boundedness of a Class of Second-order Ordinary Differential Equations With Delay', Wen Lizhi has demonstrated the criterion of the boundedness of solutions of the equation (r(t)y’)’+a(t)y+b(... In his article 'Boundedness of a Class of Second-order Ordinary Differential Equations With Delay', Wen Lizhi has demonstrated the criterion of the boundedness of solutions of the equation (r(t)y’)’+a(t)y+b(t)f(y(t-ι(t)))=p(t) (cf. Kexue Tongbao,30(1985), 1045). In this letter, we discuss the boundedness of solutions of the secondorder nonlinear functional differential 展开更多
关键词 BOUNDEDNESS LETTER CLASS CRITERION generalIZATION verified positively
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