Recently, integrating Softwaredefined networking(SDN) and network functions virtualization(NFV) are proposed to address the issue that difficulty and cost of hardwarebased and proprietary middleboxes management. Howev...Recently, integrating Softwaredefined networking(SDN) and network functions virtualization(NFV) are proposed to address the issue that difficulty and cost of hardwarebased and proprietary middleboxes management. However, it lacks of a framework that orchestrates network functions to service chain in the network cooperatively. In this paper, we propose a function combination framework that can dynamically adapt the network based on the integration NFV and SDN. There are two main contributions in this paper. First, the function combination framework based on the integration of SDN and NFV is proposed to address the function combination issue, including the architecture of Service Deliver Network, the port types representing traffic directions and the explanation of terms. Second, we formulate the issue of load balance of function combination as the model minimizing the standard deviations of all servers' loads and satisfying the demand of performance and limit of resource. The least busy placement algorithm is introduced to approach optimal solution of the problem. Finally, experimental results demonstrate that the proposed method can combine functions in an efficient and scalable way and ensure the load balance of the network.展开更多
目的:探讨机器人导航辅助置钉在骨盆髋臼骨折改良Stoppa入路手术中的应用效果。方法:本研究采用前瞻性随机对照试验设计,选取2022年11月—2024年4月于南京医科大学康达学院第一附属医院收治的102例骨盆髋臼骨折患者,按照随机数字表法分...目的:探讨机器人导航辅助置钉在骨盆髋臼骨折改良Stoppa入路手术中的应用效果。方法:本研究采用前瞻性随机对照试验设计,选取2022年11月—2024年4月于南京医科大学康达学院第一附属医院收治的102例骨盆髋臼骨折患者,按照随机数字表法分为对照组和研究组,每组51例。两组均进行改良Stoppa入路手术,对照组于C臂X线机透视下徒手完成螺钉固定,研究组在机器人导航下完成螺钉固定。比较两组患者的围手术期指标、应激指标、骨折复位优良率、改良Merle D’Aubigne and Postel评分系统评分及术后并发症情况。结果:研究组手术时间、术中透视次数、术中总出血量、总钻孔次数、住院时间少于对照组(P<0.05)。术后24 h及72 h,研究组应激指标水平低于对照组(P<0.05)。研究组骨折复位优良率高于对照组,且术后3个月、6个月、12个月改良Merle D’Aubigne and Postel评分系统评分高于对照组(P<0.05)。研究组术后并发症发生率低于对照组(P<0.05)。结论:机器人导航辅助置钉技术应用于改良Stoppa入路手术,能提高手术精准性和安全性,减少手术创伤与辐射暴露,有效控制患者围手术期应激反应,促进术后恢复,降低术后并发症发生风险。展开更多
The main objective of this paper is to study the singular natureof the crack-tip stress and electric displacement field in afunctionally gradient piezoelectric medium having materialcoefficients with a discontinuous d...The main objective of this paper is to study the singular natureof the crack-tip stress and electric displacement field in afunctionally gradient piezoelectric medium having materialcoefficients with a discontinuous derivative. The problem isconsidered for the simplest possible loading and geometry, namely,the anti-plane shear stress and electric displacement in -plane oftwo bonded half spaces in which the crack is parallel to theinterface.展开更多
The mathematical model of optimal placement of active members in truss adaptive structures is essentially a nonlinear multi-objective optimization problem with mixed variables. It is usually much difficult and costly ...The mathematical model of optimal placement of active members in truss adaptive structures is essentially a nonlinear multi-objective optimization problem with mixed variables. It is usually much difficult and costly to be solved. In this paper, the optimal location of active members is treated in terms of （0, 1） discrete variables. Structural member sizes, control gains, and （0, 1） placement variables are treated simultaneously as design variables. Then, a succinct and reasonable compromise scalar model, which is transformed from original multi-objective optimization, is established, in which the （0, 1） discrete variables are converted into an equality constraint. Secondly, by penalty function approach, the subsequent scalar mixed variable compromise model can be formulated equivalently as a sequence of continuous variable problems. Thirdly, for each continuous problem in the sequence, by choosing intermediate design variables and temporary critical constraints, the approximation concept is carried out to generate a sequence of explicit approximate problems which enhance the quality of the approximate design problems. Considering the proposed method, a FORTRAN program OPAMTAS2.0 for optimal placement of active members in truss adaptive structures is developed, which is used by the constrained variable metric method with the watchdog technique （CVMW method）. Finally, a typical 18 bar truss adaptive structure as test numerical examples is presented to illustrate that the design methodology set forth is simple, feasible, efficient and stable. The established scalar mixed variable compromise model that can avoid the ill-conditioned possibility caused by the different orders of magnitude of various objective functions in optimization process, therefore, it enables the optimization algorithm to have a good stability. On the other hand, the proposed novel optimization technique can make both discrete and continuous variables be optimized simultaneously.展开更多
The problem of robust L 1 filtering with pole constraint in a disk for linear continuous polytopic uncertain systems is discussed. The attention is focused on design a linear asymptotically stable filter such that th...The problem of robust L 1 filtering with pole constraint in a disk for linear continuous polytopic uncertain systems is discussed. The attention is focused on design a linear asymptotically stable filter such that the filtering error system remains robustly stable, and has a L 1 performance constraint and pole constraint in a disk. The new robust L 1 performance criteria and regional pole placement condition are obtained via parameter-dependent Lyapunov functions method. Upon the proposed multiobjective performance criteria and by means of LMI technique, both full-order and reduced-order robust L 1 filter with suitable dynamic behavior can be obtained from the solution of convex optimization problems. Compared with earlier result in the quadratic framework, this approach turns out to be less conservative. The efficiency of the proposed technique is demonstrated by a numerical example.展开更多
基金supported by the Foundation for Innovative Research Groups of the National Science Foundation of China (Grant No.61521003)The National Basic Research Program of China(973)(Grant No.2012CB315901,2013CB329104)+1 种基金The National Natural Science Foundation of China(Grant No.61372121,61309019,61309020)The National High Technology Research and Development Program of China(863)(Grant No.2015AA016102,2013AA013505)
文摘Recently, integrating Softwaredefined networking(SDN) and network functions virtualization(NFV) are proposed to address the issue that difficulty and cost of hardwarebased and proprietary middleboxes management. However, it lacks of a framework that orchestrates network functions to service chain in the network cooperatively. In this paper, we propose a function combination framework that can dynamically adapt the network based on the integration NFV and SDN. There are two main contributions in this paper. First, the function combination framework based on the integration of SDN and NFV is proposed to address the function combination issue, including the architecture of Service Deliver Network, the port types representing traffic directions and the explanation of terms. Second, we formulate the issue of load balance of function combination as the model minimizing the standard deviations of all servers' loads and satisfying the demand of performance and limit of resource. The least busy placement algorithm is introduced to approach optimal solution of the problem. Finally, experimental results demonstrate that the proposed method can combine functions in an efficient and scalable way and ensure the load balance of the network.
文摘目的:探讨机器人导航辅助置钉在骨盆髋臼骨折改良Stoppa入路手术中的应用效果。方法:本研究采用前瞻性随机对照试验设计,选取2022年11月—2024年4月于南京医科大学康达学院第一附属医院收治的102例骨盆髋臼骨折患者,按照随机数字表法分为对照组和研究组,每组51例。两组均进行改良Stoppa入路手术,对照组于C臂X线机透视下徒手完成螺钉固定,研究组在机器人导航下完成螺钉固定。比较两组患者的围手术期指标、应激指标、骨折复位优良率、改良Merle D’Aubigne and Postel评分系统评分及术后并发症情况。结果:研究组手术时间、术中透视次数、术中总出血量、总钻孔次数、住院时间少于对照组(P<0.05)。术后24 h及72 h,研究组应激指标水平低于对照组(P<0.05)。研究组骨折复位优良率高于对照组,且术后3个月、6个月、12个月改良Merle D’Aubigne and Postel评分系统评分高于对照组(P<0.05)。研究组术后并发症发生率低于对照组(P<0.05)。结论:机器人导航辅助置钉技术应用于改良Stoppa入路手术,能提高手术精准性和安全性,减少手术创伤与辐射暴露,有效控制患者围手术期应激反应,促进术后恢复,降低术后并发症发生风险。
基金the National Natural Science Foundation of China (No.10072041)the National Excellent Young Scholar Fund of China (No.10125209)the Teaching and Research Award Program for Outstanding Young Teachers in Higher Education Institutions of MOE,P.R.C..
文摘The main objective of this paper is to study the singular natureof the crack-tip stress and electric displacement field in afunctionally gradient piezoelectric medium having materialcoefficients with a discontinuous derivative. The problem isconsidered for the simplest possible loading and geometry, namely,the anti-plane shear stress and electric displacement in -plane oftwo bonded half spaces in which the crack is parallel to theinterface.
基金supported by National Natural Science Foundation of China(Grant No.10472007)
文摘The mathematical model of optimal placement of active members in truss adaptive structures is essentially a nonlinear multi-objective optimization problem with mixed variables. It is usually much difficult and costly to be solved. In this paper, the optimal location of active members is treated in terms of （0, 1） discrete variables. Structural member sizes, control gains, and （0, 1） placement variables are treated simultaneously as design variables. Then, a succinct and reasonable compromise scalar model, which is transformed from original multi-objective optimization, is established, in which the （0, 1） discrete variables are converted into an equality constraint. Secondly, by penalty function approach, the subsequent scalar mixed variable compromise model can be formulated equivalently as a sequence of continuous variable problems. Thirdly, for each continuous problem in the sequence, by choosing intermediate design variables and temporary critical constraints, the approximation concept is carried out to generate a sequence of explicit approximate problems which enhance the quality of the approximate design problems. Considering the proposed method, a FORTRAN program OPAMTAS2.0 for optimal placement of active members in truss adaptive structures is developed, which is used by the constrained variable metric method with the watchdog technique （CVMW method）. Finally, a typical 18 bar truss adaptive structure as test numerical examples is presented to illustrate that the design methodology set forth is simple, feasible, efficient and stable. The established scalar mixed variable compromise model that can avoid the ill-conditioned possibility caused by the different orders of magnitude of various objective functions in optimization process, therefore, it enables the optimization algorithm to have a good stability. On the other hand, the proposed novel optimization technique can make both discrete and continuous variables be optimized simultaneously.
文摘The problem of robust L 1 filtering with pole constraint in a disk for linear continuous polytopic uncertain systems is discussed. The attention is focused on design a linear asymptotically stable filter such that the filtering error system remains robustly stable, and has a L 1 performance constraint and pole constraint in a disk. The new robust L 1 performance criteria and regional pole placement condition are obtained via parameter-dependent Lyapunov functions method. Upon the proposed multiobjective performance criteria and by means of LMI technique, both full-order and reduced-order robust L 1 filter with suitable dynamic behavior can be obtained from the solution of convex optimization problems. Compared with earlier result in the quadratic framework, this approach turns out to be less conservative. The efficiency of the proposed technique is demonstrated by a numerical example.
