The purpose of this paper is to apply inertial technique to string averaging projection method and block-iterative projection method in order to get two accelerated projection algorithms for solving convex feasibility...The purpose of this paper is to apply inertial technique to string averaging projection method and block-iterative projection method in order to get two accelerated projection algorithms for solving convex feasibility problem.Compared with the existing accelerated methods for solving the problem,the inertial technique employs a parameter sequence and two previous iterations to get the next iteration and hence improves the flexibility of the algorithm.Theoretical asymptotic convergence results are presented under some suitable conditions.Numerical simulations illustrate that the new methods have better convergence than the general projection methods.The presented algorithms are inspired by the inertial proximal point algorithm for finding zeros of a maximal monotone operator.展开更多
An ε-subgradient projection algorithm for solving a convex feasibility problem is presented.Based on the iterative projection methods and the notion of ε-subgradient,a series of special projection hyperplanes is est...An ε-subgradient projection algorithm for solving a convex feasibility problem is presented.Based on the iterative projection methods and the notion of ε-subgradient,a series of special projection hyperplanes is established.Moreover,compared with the existing projection hyperplanes methods with subgradient,the proposed hyperplanes are interactive with ε,and their ranges are more larger.The convergence of the proposed algorithm is given under some mild conditions,and the validity of the algorithm is proved by the numerical test.展开更多
Controlled,guided munitions can reduce dispersion in the shot,while providing the capability of engaging both stationary and maneuvering targets.The Netherlands Organisation for Applied Scientific Research has develop...Controlled,guided munitions can reduce dispersion in the shot,while providing the capability of engaging both stationary and maneuvering targets.The Netherlands Organisation for Applied Scientific Research has developed a fin-less control technology called Stagnation Pressure Reaction Control(SPRC)that takes stagnation pressure air and directs it sideways to control non-spinning projectiles.In a previous study,this technology was demonstrated at Mach 2 wind-tunnel conditions to achieve up to 1.5°controllable angle of incidence for a non-spinning,aerodynamically unstable projectile-like test object.In an operational scenario,the decelerating projectile will experience a decline in control force while the simultaneous forward shift of the center of pressure increases the need for control force.Furthermore,angles of incidence exceeding 1.5°will be experienced under realistic flight conditions,especially against maneuvering targets.This work addresses these challenges and presents an operational feasibility study for a practical application of SPRC in a non-spinning mid-caliber gun-launched projectile,using experiment data on control latency and force of the earlier study.It illustrates the combined effect of the control-and stability dynamics and underlines the potential of an SPRC projectile as a precisionoperation ammunition.This research revealed that SPRC technology can stabilize and control the hypothesized projectile in a direct fire scenario against stationary and maneuvering targets.展开更多
Objective To probe the clinic feasibility of percutaneous coronary intervention(PCI) via transulnar artery approach (PCI TRU).Methods Fourty patients with unstable ischemic manifestation(male 34,female 6;age 59.3 ...Objective To probe the clinic feasibility of percutaneous coronary intervention(PCI) via transulnar artery approach (PCI TRU).Methods Fourty patients with unstable ischemic manifestation(male 34,female 6;age 59.3 ±9.10 years)whose radial artery of right hand was thin with a weak pulse that was not suitable to transradial artery PCI while whose ulnar artery was thick with a strong pulse based on their larger diameter in ulnar artery as compared with those in radial artery ( 3.30 ±0.22mm vs 2.43 ±0.33 mm, P <0.05 ) by the investigation of vessel echography,but revesered Allen’s test for radial and ulnar artery was positive,were selected as the subjects for PCI TRU. The radio of ulnar artery versus radial artery was 1.35:1.00 and the time of Allen’s test in ulnar artery side was shorter than that in radial artery side ( 2.70 ±0.36 s vs 4.68 ±0.52s , P <0.05 ) before PCI. The efficiency of PCI TRU was evaluated. The time of manipulative duration for each procedure of PCI TRU was recorded. The time of Allen’s test, luminal diameter (mm) , cross area of vessel lumin (mm 2), blood velocity (Vs max), blood resistance (RI) in ulnar artery and radial artery and the level of blood oxygen in finger (PaO 2、SatO 2) were measured and recorded , respectively , as well were compared quantitatively before and after 1 month of procedure . Results Fourty eight lesion segments of 42 vessels in all patients were angioplasticized successfully via TRU by 6F guiding catheter including 23 segments of type B1 , 14 segments of type B2 and 11 segments of type C. PCI TRU in all of 40 patients was performed successfully. Fourty eight stents were implanted including 2 lesions of intrastent restenosis angioplasticized with cutting balloon technique before re stenting . The average time of manipulative duration of guiding catheters engaging in osicum of target coronary, crossing the vessel lesions of guidewire, dilatation and implantation of stents,and under X ray fluoroscopy were 4.30 ±0.59 min , 2.52 ±0.40min , 2.66 ±0.40 min ,and 25.9 ±0.49 min , respectively, and the total time of the whole procedure was 56.6 ±14.8 min . When the ulnar introducer was taken off, the access site in ulnar artery was suppressed by tourniquet with no bleeding in the access site and no limitation of physical activation under maintaining infusion of heparin immediately after procedure . There was no significant change in the diameter of ulnar artery and the time of Allen’s test after 1 month of PCI procedure as compared with those before procedure ( 3.22 ±0.48mm vs 3.26 ±0.22 mm , P >0.05 ; 2.96 ±0.98 s vs 2.72 ±0.47 s , P >0.05 ). No significant change was found in the parameters of blood velocity , cross area of vessel lumin, blood resistance and the level of blood oxygen in finger after 1 month of PCI procedure. The average total hospital stay was 5.21 ±0.43 days. Following up 1 month, no complications such as occlusion of ulnar artery, abnormal sensitivity and movement disability were found in right hands in all patients.Conclusions The ulnar artery might be selected as one approach of antebrachial artery for PCI in the patients with coronary heart disease whose radial artery was difficulty as access vessels of PCI, while reversed Allen’s test for radial and ulnar artery are positive and the luminal diameter of ulnar artery was larger than that of radial artery.展开更多
A novel encryption model is proposed. It combines encryption process with compression process, and realizes compression and encryption at the same time. The model's feasibility and security are analyzed in detail. An...A novel encryption model is proposed. It combines encryption process with compression process, and realizes compression and encryption at the same time. The model's feasibility and security are analyzed in detail. And the relationship between its security and compression ratio is also analyzed.展开更多
The basic way and method to apply the equipment s CAD data to a geometry description system(GDS) are presented,and its interface to GDS is set up.The basic function,flow and implementation technique of the interface a...The basic way and method to apply the equipment s CAD data to a geometry description system(GDS) are presented,and its interface to GDS is set up.The basic function,flow and implementation technique of the interface are analyzed.Special computer software is programmed,and an application example is given also.The research results indicate that this interface can assist to derive desired data from the CAD data,and provide powerful technical support for the development of a practical data transferring interface.展开更多
With the development of anti-radiation weapons,the effectiveness evaluation of anti-radiation weapons has been turned from the simple accuracy index to the integrated countermeasure capability.The research priority is...With the development of anti-radiation weapons,the effectiveness evaluation of anti-radiation weapons has been turned from the simple accuracy index to the integrated countermeasure capability.The research priority is how to access the combat effectiveness of anti-radiation weapons in a complex countermeasure environment.For the present situation of range test of anti-radiation weapons,a combat effectiveness assessment model based on non-linear index aggregation is proposed for anti-radiation weapons.And the corresponding index system model,index aggregation methods,index marking method and index weight determination are given.Finally,the simulation results verify the efficiency and feasibility of the proposed method.展开更多
In coordination of the construction of concealed work of levee project, the research on the soil quality of Jingnan levee in Hubei province was carried out through test. The results demonstrate: ① the Jingnan levee e...In coordination of the construction of concealed work of levee project, the research on the soil quality of Jingnan levee in Hubei province was carried out through test. The results demonstrate: ① the Jingnan levee embankment is in bad quality, the compaction degree of most levee sections doesn’t reach 92%; the average compressive coefficient of the levee backfilled soils is about 0.3 MPa; the seepage coefficients are 10\+ -5 ~10\+ -6 cm/s generally; the levee body was compacted unevenly; ② the soil layers of the levee foundation are distributed complicatedly and generally in low density; the void ratios of various soils are mostly in 0.7~1, indicating that the foundation soils are generally in loose state; ③ the pH value of levee body and foundation is 7.05~8.95, attributing to weak alkaline and not producing significant influence on liquid-plastic limit and shear strength of soils, the content of strongly soluble salt of levee foundation soils is 0.01%~0.52% and will not produce great influence on the mechanical behaviours of soils.展开更多
The organization of coordinated attack and the selection of aiming point which affect hit probability were analyzed for the countermeasures taken by the hostile submarines at two helicopters' coordinated attack.A ...The organization of coordinated attack and the selection of aiming point which affect hit probability were analyzed for the countermeasures taken by the hostile submarines at two helicopters' coordinated attack.A computational model of coordinated attack parameters,a model of submarine maneuver,and a model of noise jammer were established.Compared to single helicopter' torpedo attack,the coordinated attack of two helicopters can effectively increase the hit probability of torpedo and achieve the higher target detecting probability under counterwork condition.展开更多
With applying the information technology to the military field, the advantages and importance of the networked combat are more and more obvious. In order to make full use of limited battlefield resources and maximally...With applying the information technology to the military field, the advantages and importance of the networked combat are more and more obvious. In order to make full use of limited battlefield resources and maximally destroy enemy targets from arbitrary angle in a limited time, the research on firepower nodes dynamic deployment becomes a key problem of command and control. Considering a variety of tactical indexes and actual constraints in air defense, a mathematical model is formulated to minimize the enemy target penetration probability. Based on characteristics of the mathematical model and demands of the deployment problems, an assistance-based algorithm is put forward which combines the artificial potential field (APF) method with a memetic algorithm. The APF method is employed to solve the constraint handling problem and generate feasible solutions. The constrained optimization problem transforms into an optimization problem of APF parameters adjustment, and the dimension of the problem is reduced greatly. The dynamic deployment is accomplished by generation and refinement of feasible solutions. The simulation results show that the proposed algorithm is effective and feasible in dynamic situation.展开更多
Multidisciplinary feasible method (MDF) is conventional method to multidisciplinary optimization (MDO) and well-understood by users. It reduces the dimensions of the multidisciplinary optimization problem by using the...Multidisciplinary feasible method (MDF) is conventional method to multidisciplinary optimization (MDO) and well-understood by users. It reduces the dimensions of the multidisciplinary optimization problem by using the design variables as independent optimization variables. However, at each iteration of the conventional optimization procedure, multidisciplinary analysis (MDA) is numerously performed that results in extreme expense and low optimization efficiency. The intrinsic weakness of MDF is due to the times that it loop fixed-point iterations in MDA, which drive us to improve MDF by building inexpensive approximations as surrogates for expensive MDA. An simple example is presented to demonstrate the usefulness of the improved MDF. Results show that a significant reduction in the number of multidisciplinary analysis required for optimization is obtained as compared with original MDF and the efficiency of optimization is increased.展开更多
In the world, most of the successes are results of longterm efforts. The reward of success is extremely high, but before that, a long-term investment process is required. People who are “myopic” only value short-ter...In the world, most of the successes are results of longterm efforts. The reward of success is extremely high, but before that, a long-term investment process is required. People who are “myopic” only value short-term rewards and are unwilling to make early-stage investments, so they hardly get the ultimate success and the corresponding high rewards. Similarly, for a reinforcement learning(RL) model with long-delay rewards, the discount rate determines the strength of agent’s “farsightedness”.In order to enable the trained agent to make a chain of correct choices and succeed finally, the feasible region of the discount rate is obtained through mathematical derivation in this paper firstly. It satisfies the “farsightedness” requirement of agent. Afterwards, in order to avoid the complicated problem of solving implicit equations in the process of choosing feasible solutions,a simple method is explored and verified by theoreti cal demonstration and mathematical experiments. Then, a series of RL experiments are designed and implemented to verify the validity of theory. Finally, the model is extended from the finite process to the infinite process. The validity of the extended model is verified by theories and experiments. The whole research not only reveals the significance of the discount rate, but also provides a theoretical basis as well as a practical method for the choice of discount rate in future researches.展开更多
To determine the reasonable resource dependent relations between activities for the purpose of exactly computing the total floats and the free floats of activities, correctly identifying critical activities and critic...To determine the reasonable resource dependent relations between activities for the purpose of exactly computing the total floats and the free floats of activities, correctly identifying critical activities and critical sequences in a project schedule with variable resource constraints, the concept of the minimal feasible set (MFS) is proposed and the properties of MFS are discussed. The methods to identify optimal MFSs and resource links are then studied. Furthermore, MFS is generalized to the situation that the preconditions of MFS are not satisfied. Contrastive results show that in establishing resource links and resolving floats, MFS is at least not inferior to other methods in all cases and is superior in most situations.展开更多
基金supported by the National Natural Science Foundation of China (11171221)Shanghai Municipal Committee of Science and Technology (10550500800)+1 种基金Basic and Frontier Research Program of Science and Technology Department of Henan Province (112300410277,082300440150)China Coal Industry Association Scientific and Technical Guidance to Project (MTKJ-2011-403)
文摘The purpose of this paper is to apply inertial technique to string averaging projection method and block-iterative projection method in order to get two accelerated projection algorithms for solving convex feasibility problem.Compared with the existing accelerated methods for solving the problem,the inertial technique employs a parameter sequence and two previous iterations to get the next iteration and hence improves the flexibility of the algorithm.Theoretical asymptotic convergence results are presented under some suitable conditions.Numerical simulations illustrate that the new methods have better convergence than the general projection methods.The presented algorithms are inspired by the inertial proximal point algorithm for finding zeros of a maximal monotone operator.
基金supported by the National Natural Science Foundation of China (10671126)Shanghai Leading Academic Discipline Project(S30501)
文摘An ε-subgradient projection algorithm for solving a convex feasibility problem is presented.Based on the iterative projection methods and the notion of ε-subgradient,a series of special projection hyperplanes is established.Moreover,compared with the existing projection hyperplanes methods with subgradient,the proposed hyperplanes are interactive with ε,and their ranges are more larger.The convergence of the proposed algorithm is given under some mild conditions,and the validity of the algorithm is proved by the numerical test.
文摘Controlled,guided munitions can reduce dispersion in the shot,while providing the capability of engaging both stationary and maneuvering targets.The Netherlands Organisation for Applied Scientific Research has developed a fin-less control technology called Stagnation Pressure Reaction Control(SPRC)that takes stagnation pressure air and directs it sideways to control non-spinning projectiles.In a previous study,this technology was demonstrated at Mach 2 wind-tunnel conditions to achieve up to 1.5°controllable angle of incidence for a non-spinning,aerodynamically unstable projectile-like test object.In an operational scenario,the decelerating projectile will experience a decline in control force while the simultaneous forward shift of the center of pressure increases the need for control force.Furthermore,angles of incidence exceeding 1.5°will be experienced under realistic flight conditions,especially against maneuvering targets.This work addresses these challenges and presents an operational feasibility study for a practical application of SPRC in a non-spinning mid-caliber gun-launched projectile,using experiment data on control latency and force of the earlier study.It illustrates the combined effect of the control-and stability dynamics and underlines the potential of an SPRC projectile as a precisionoperation ammunition.This research revealed that SPRC technology can stabilize and control the hypothesized projectile in a direct fire scenario against stationary and maneuvering targets.
文摘Objective To probe the clinic feasibility of percutaneous coronary intervention(PCI) via transulnar artery approach (PCI TRU).Methods Fourty patients with unstable ischemic manifestation(male 34,female 6;age 59.3 ±9.10 years)whose radial artery of right hand was thin with a weak pulse that was not suitable to transradial artery PCI while whose ulnar artery was thick with a strong pulse based on their larger diameter in ulnar artery as compared with those in radial artery ( 3.30 ±0.22mm vs 2.43 ±0.33 mm, P <0.05 ) by the investigation of vessel echography,but revesered Allen’s test for radial and ulnar artery was positive,were selected as the subjects for PCI TRU. The radio of ulnar artery versus radial artery was 1.35:1.00 and the time of Allen’s test in ulnar artery side was shorter than that in radial artery side ( 2.70 ±0.36 s vs 4.68 ±0.52s , P <0.05 ) before PCI. The efficiency of PCI TRU was evaluated. The time of manipulative duration for each procedure of PCI TRU was recorded. The time of Allen’s test, luminal diameter (mm) , cross area of vessel lumin (mm 2), blood velocity (Vs max), blood resistance (RI) in ulnar artery and radial artery and the level of blood oxygen in finger (PaO 2、SatO 2) were measured and recorded , respectively , as well were compared quantitatively before and after 1 month of procedure . Results Fourty eight lesion segments of 42 vessels in all patients were angioplasticized successfully via TRU by 6F guiding catheter including 23 segments of type B1 , 14 segments of type B2 and 11 segments of type C. PCI TRU in all of 40 patients was performed successfully. Fourty eight stents were implanted including 2 lesions of intrastent restenosis angioplasticized with cutting balloon technique before re stenting . The average time of manipulative duration of guiding catheters engaging in osicum of target coronary, crossing the vessel lesions of guidewire, dilatation and implantation of stents,and under X ray fluoroscopy were 4.30 ±0.59 min , 2.52 ±0.40min , 2.66 ±0.40 min ,and 25.9 ±0.49 min , respectively, and the total time of the whole procedure was 56.6 ±14.8 min . When the ulnar introducer was taken off, the access site in ulnar artery was suppressed by tourniquet with no bleeding in the access site and no limitation of physical activation under maintaining infusion of heparin immediately after procedure . There was no significant change in the diameter of ulnar artery and the time of Allen’s test after 1 month of PCI procedure as compared with those before procedure ( 3.22 ±0.48mm vs 3.26 ±0.22 mm , P >0.05 ; 2.96 ±0.98 s vs 2.72 ±0.47 s , P >0.05 ). No significant change was found in the parameters of blood velocity , cross area of vessel lumin, blood resistance and the level of blood oxygen in finger after 1 month of PCI procedure. The average total hospital stay was 5.21 ±0.43 days. Following up 1 month, no complications such as occlusion of ulnar artery, abnormal sensitivity and movement disability were found in right hands in all patients.Conclusions The ulnar artery might be selected as one approach of antebrachial artery for PCI in the patients with coronary heart disease whose radial artery was difficulty as access vessels of PCI, while reversed Allen’s test for radial and ulnar artery are positive and the luminal diameter of ulnar artery was larger than that of radial artery.
基金supported by the National Natural Science Foundation of China(60903197)the Major State Basic Research Development Program of China(2007CB310800)+1 种基金the Major Research Plan of the National Natural Science Foundation of China (90718006)the Foundation of Key Laboratory of Aerospace Information Security and Trust Computing Ministry of Education.
文摘A novel encryption model is proposed. It combines encryption process with compression process, and realizes compression and encryption at the same time. The model's feasibility and security are analyzed in detail. And the relationship between its security and compression ratio is also analyzed.
文摘The basic way and method to apply the equipment s CAD data to a geometry description system(GDS) are presented,and its interface to GDS is set up.The basic function,flow and implementation technique of the interface are analyzed.Special computer software is programmed,and an application example is given also.The research results indicate that this interface can assist to derive desired data from the CAD data,and provide powerful technical support for the development of a practical data transferring interface.
文摘With the development of anti-radiation weapons,the effectiveness evaluation of anti-radiation weapons has been turned from the simple accuracy index to the integrated countermeasure capability.The research priority is how to access the combat effectiveness of anti-radiation weapons in a complex countermeasure environment.For the present situation of range test of anti-radiation weapons,a combat effectiveness assessment model based on non-linear index aggregation is proposed for anti-radiation weapons.And the corresponding index system model,index aggregation methods,index marking method and index weight determination are given.Finally,the simulation results verify the efficiency and feasibility of the proposed method.
文摘In coordination of the construction of concealed work of levee project, the research on the soil quality of Jingnan levee in Hubei province was carried out through test. The results demonstrate: ① the Jingnan levee embankment is in bad quality, the compaction degree of most levee sections doesn’t reach 92%; the average compressive coefficient of the levee backfilled soils is about 0.3 MPa; the seepage coefficients are 10\+ -5 ~10\+ -6 cm/s generally; the levee body was compacted unevenly; ② the soil layers of the levee foundation are distributed complicatedly and generally in low density; the void ratios of various soils are mostly in 0.7~1, indicating that the foundation soils are generally in loose state; ③ the pH value of levee body and foundation is 7.05~8.95, attributing to weak alkaline and not producing significant influence on liquid-plastic limit and shear strength of soils, the content of strongly soluble salt of levee foundation soils is 0.01%~0.52% and will not produce great influence on the mechanical behaviours of soils.
文摘The organization of coordinated attack and the selection of aiming point which affect hit probability were analyzed for the countermeasures taken by the hostile submarines at two helicopters' coordinated attack.A computational model of coordinated attack parameters,a model of submarine maneuver,and a model of noise jammer were established.Compared to single helicopter' torpedo attack,the coordinated attack of two helicopters can effectively increase the hit probability of torpedo and achieve the higher target detecting probability under counterwork condition.
基金supported by the National Outstanding Youth Science Foundation (60925011)the National Natural Science Foundation of China (61203181)
文摘With applying the information technology to the military field, the advantages and importance of the networked combat are more and more obvious. In order to make full use of limited battlefield resources and maximally destroy enemy targets from arbitrary angle in a limited time, the research on firepower nodes dynamic deployment becomes a key problem of command and control. Considering a variety of tactical indexes and actual constraints in air defense, a mathematical model is formulated to minimize the enemy target penetration probability. Based on characteristics of the mathematical model and demands of the deployment problems, an assistance-based algorithm is put forward which combines the artificial potential field (APF) method with a memetic algorithm. The APF method is employed to solve the constraint handling problem and generate feasible solutions. The constrained optimization problem transforms into an optimization problem of APF parameters adjustment, and the dimension of the problem is reduced greatly. The dynamic deployment is accomplished by generation and refinement of feasible solutions. The simulation results show that the proposed algorithm is effective and feasible in dynamic situation.
文摘Multidisciplinary feasible method (MDF) is conventional method to multidisciplinary optimization (MDO) and well-understood by users. It reduces the dimensions of the multidisciplinary optimization problem by using the design variables as independent optimization variables. However, at each iteration of the conventional optimization procedure, multidisciplinary analysis (MDA) is numerously performed that results in extreme expense and low optimization efficiency. The intrinsic weakness of MDF is due to the times that it loop fixed-point iterations in MDA, which drive us to improve MDF by building inexpensive approximations as surrogates for expensive MDA. An simple example is presented to demonstrate the usefulness of the improved MDF. Results show that a significant reduction in the number of multidisciplinary analysis required for optimization is obtained as compared with original MDF and the efficiency of optimization is increased.
基金supported by the National Natural Science Foundation of China (717712167170120972001214)。
文摘In the world, most of the successes are results of longterm efforts. The reward of success is extremely high, but before that, a long-term investment process is required. People who are “myopic” only value short-term rewards and are unwilling to make early-stage investments, so they hardly get the ultimate success and the corresponding high rewards. Similarly, for a reinforcement learning(RL) model with long-delay rewards, the discount rate determines the strength of agent’s “farsightedness”.In order to enable the trained agent to make a chain of correct choices and succeed finally, the feasible region of the discount rate is obtained through mathematical derivation in this paper firstly. It satisfies the “farsightedness” requirement of agent. Afterwards, in order to avoid the complicated problem of solving implicit equations in the process of choosing feasible solutions,a simple method is explored and verified by theoreti cal demonstration and mathematical experiments. Then, a series of RL experiments are designed and implemented to verify the validity of theory. Finally, the model is extended from the finite process to the infinite process. The validity of the extended model is verified by theories and experiments. The whole research not only reveals the significance of the discount rate, but also provides a theoretical basis as well as a practical method for the choice of discount rate in future researches.
基金supported partly by the Postdoctoral Science Foundation of China(2007042-0922)the Program of Educational Commission of Guangxi Zhuang Minority Autonomous Region(200712LX128)the Scientific Research Foundation of Guangxi University for Nationalities for Talent Introduction(200702YZ01).
文摘To determine the reasonable resource dependent relations between activities for the purpose of exactly computing the total floats and the free floats of activities, correctly identifying critical activities and critical sequences in a project schedule with variable resource constraints, the concept of the minimal feasible set (MFS) is proposed and the properties of MFS are discussed. The methods to identify optimal MFSs and resource links are then studied. Furthermore, MFS is generalized to the situation that the preconditions of MFS are not satisfied. Contrastive results show that in establishing resource links and resolving floats, MFS is at least not inferior to other methods in all cases and is superior in most situations.