Based on the similarity of separation time,a similarity law optimization method for high-speed weapon delivery test is derived.The typical separation state under wind load is simulated by the numerical method.The real...Based on the similarity of separation time,a similarity law optimization method for high-speed weapon delivery test is derived.The typical separation state under wind load is simulated by the numerical method.The real separation data of aircraft,separation data of previous test methods,separation data of ideal wind tunnel test of previous methods,and simulation data of the proposed optimization method are obtained.A comparison of the data shows that the method proposed can improve the performance of tracking.Similarity law optimization starts with the development of motion equations and dynamic equations in the windless state to address the problems of mismatching between vertical and horizontal displacement,and to address the problems of separation trajectory distortion caused by insufficient gravity acceleration of the scaling model of existing light model.The ejection velocity of the model is taken as a factor/vector,and is adjusted reasonably to compensate the linear displacement insufficiency caused by the insufficient vertical acceleration of the light model method,so as to ensure the matching of the vertical and horizontal displacement of the projectile,and to improve the consistency between the test results of high-speed projection and the actual separation trajectory.The optimized similarity law is applicable to many existing free-throwing modes of high-speed wind tunnels.The optimized similarity law is not affected by the ejection velocity and hanging mode of the projectile.The optimized similarity law is suitable not only for the launching of the buried ammunition compartment and external stores,but also for the test design of projectile launching and gravity separation.展开更多
The co-operation action mechanism and model of photon-ion catalysis synergy material composed of thallium and valency-variable rare earth elements and semiconductor oxide were proposed. The radiation catalysis reactio...The co-operation action mechanism and model of photon-ion catalysis synergy material composed of thallium and valency-variable rare earth elements and semiconductor oxide were proposed. The radiation catalysis reactions of water and oxygen assisted by the synergy material that could largely increase electron, free radical and negative ion products were discussed. The applications of photon-ion catalysis synergy material in areas of air cleaning material, antibacterial material , healthy material and energy resource material were suggested.展开更多
The effective way of finding the yarn curve shape and tension of OE(open end) yarn inside the rotor is carried out and treated by dividing the yarn curve into two parts, from which the trajectory of the yarn sliding o...The effective way of finding the yarn curve shape and tension of OE(open end) yarn inside the rotor is carried out and treated by dividing the yarn curve into two parts, from which the trajectory of the yarn sliding on the navel surface is also obtained. It is pointed out that the yarn curve shape and tension will both fluctuate with the trajectory's revolving cycle inside the rotor. However, the fluctuation is not too great, so the motion can still be regarded as approximately steady for dynamic analysis.展开更多
Effect of rare earth elements (RE) on erosion resistance of nitrocarburized layer of 38CrMoAl steel was investigated. The results indicate that significant improvement occurs in erosion resistance of nitrocarburized 3...Effect of rare earth elements (RE) on erosion resistance of nitrocarburized layer of 38CrMoAl steel was investigated. The results indicate that significant improvement occurs in erosion resistance of nitrocarburized 38CrMoAl steel by introducing RE during nitrocarburizing processing as compared with conventional nitrocarburizing processing. Results of mechanical testing show that both hardness and impact toughness of RE-nitrocarburizing layer of 38CrMoAl steel increase as compared with the conventional one. Optical microscopy reveals that there is improvement in the nitrocarburized layer attributed to the introduction of RE, which results in improvement in erosion resistance. Surface morphology observation of tested samples reveals that predominantly furrow-like peelings from plastic deformation are observed for RE nitrocarburizied 38CrMoAl steel, while the furrow-like peeling with initial cross crack and large grinding peelings were observed for conventionally nitrocarburized samples.展开更多
Steel structure system of crane deteriorates over time due to environmental effects, material fatigue, and overloading. System structural reliability and remaining service life assessment methods are developed during ...Steel structure system of crane deteriorates over time due to environmental effects, material fatigue, and overloading. System structural reliability and remaining service life assessment methods are developed during the few decades. But until now estimating remaining service life methods of crane steel system by reliability theory begin to develop. Safety assessment of existing steel structure system requires the development of a methodology that allows for an accurate evaluation of reliability and prediction of the remaining life. Steel structures are the supporting elements in the special equipment such as hoisting machinery. Structure reliability and remaining service life safe assessment are important for steel structures. For finding the reason which caused the failure modes （such as fatigue strength failure, stiffness failure and stability failure）, incremental loading method based on possibilistic reliability is applied into dynamic structure failure path research. Through reliability analyzing and calculating for crane, it is demonstrated that fatigue damage is the most common failure mode. Fuzzy fatigue damage accumulation theory is used for basis theory and Paris-Eadogan equations are used for mathematical modeling. All fatigue parameter values of the welding box girder of bridge cranes are determined and fatigue remaining life formulas are deduced. After field test and collecting working parameters of numerous cranes, typical fatigue load spectrum was compiled for the dangerous point of box girders used in the area. Fatigue remaining life is assessed for different types and lifting capacities. Safety for steel structure system of bridge crane is assessed by two quantitative indexs： reliability and remaining life. Therefore, the evaluation means is more comprehensive and reasonable. The example shows that the two quantitative indexs are mutually correlated. Through analyzing the 120 t-22.5 m bridge crane of a certain enterprise, a new methodology to estimate remaining service life of steel structure by possibilistic reliability theory is introduced for safety evaluation of structure system.展开更多
Large quantity of negative ions and hydrogen can be produced continuously by metal ions of tourmaline under the synergy action of light, water and oxygen. In order to promote this effect, the photon-ion-catalyzed rare...Large quantity of negative ions and hydrogen can be produced continuously by metal ions of tourmaline under the synergy action of light, water and oxygen. In order to promote this effect, the photon-ion-catalyzed rare earth functional synergy material was prepared to simulate the nature properties of tourmaline. Its safety was discussed and an interaction model proposed. The investigation results show that the cooperation of sunlight, valency-variable rare earth element thorium includes material and photo-catalyzed TiO_2 can increase the product of free radicals and negative ions. It is safety to use thorium included rare earth or rare earth waste with radiant dose smaller than 1Gy.展开更多
The properties of rare earth materials activated diesel oil such as temperature, density and hydroxylic radical were discussed. Rare earth materials including minim thorium oxide powders which had radioactivity were m...The properties of rare earth materials activated diesel oil such as temperature, density and hydroxylic radical were discussed. Rare earth materials including minim thorium oxide powders which had radioactivity were mainly composed of rare earth waste-residue powders. Under the radiation catalysis of rare earth materials, molecules of diesel oil can be transformed into activated molecules, the collision frequency increases among molecules, and temperature raises a little higher than usual. When temperature is higher, the interaction force between molecules is lessened, distance between molecules is shortened. The volume is increased and the density is decreased. A large amounts electrons and negative ions are produced by rare earth materials, which leads to the signals of hydroxylic radical stronger that means rare earth materials can activate diesel oil and can improve the activity of diesel oil.展开更多
We propose a scheme to achieve a kind of nontrivial multipartite pair-wise controlled phase operation in a cavity QED setup. The operation implemented is of geometrical nature and is not sensitive to the thermal state...We propose a scheme to achieve a kind of nontrivial multipartite pair-wise controlled phase operation in a cavity QED setup. The operation implemented is of geometrical nature and is not sensitive to the thermal state of the cavity. In particular, we have managed to avoid the conventional dispersive coupling so that high speed gate operation is achieved which is very important in view of decoherence. We show that this multipartite pair-wise controlled phase operation makes the generation of two-dimensional cluster states very efficient.展开更多
Aiming at the problems of low-level information sharing, slow transmission and repetitive work in the designing process of product series, the internet-oriented parametric collaborative design method is proposed, in w...Aiming at the problems of low-level information sharing, slow transmission and repetitive work in the designing process of product series, the internet-oriented parametric collaborative design method is proposed, in which the problems of sharing conflict and network heterogeneous in the distributed collaborative design are analyzed, and the construction method of collaborative design platforms based on PDMWorks Workgroup is put forward. Through studying the mechanism of roles distribution and function allocation and data concurrency control, the communication mechanism of internet-oriented collaborative design is formulated. On the basis of structure features of overhead travelling crane, through combining parametric variant design with collaborative design, internet-oriented parametric collaborative design system of overhead travelling crane is developed and verified through main girder design. In the paper, the internet-oriented parametric collaborative design method is proposed, aiming to solve the problems of low-level information sharing, slow transmission and repetitive work in the designing process of product series. The problems of sharing conflict and network heterogeneous in the distributed collaborative design are analyzed. The construction method of collaborative design platforms based on PDMWorks Workgroup is put forward. The communication mechanism of internet-oriented collaborative design is formulated, through studying the mechanism of roles distribution and function allocation and data concurrency control. On the basis of structure features of overhead travelling crane, through combining parametric variant design with collaborative design, internet-oriented parametric collaborative design system of overhead travelling crane is developed and verified through main girder design.展开更多
Spectral energy distribution of surface EMG signal is often used but difficultly and effectively control artificial limb, because the spectral energy distribution changes in the process of limb actions. In this paper,...Spectral energy distribution of surface EMG signal is often used but difficultly and effectively control artificial limb, because the spectral energy distribution changes in the process of limb actions. In this paper, the general characteristics of surface EMG signal patterns were firstly characterized by spectral energy change. 13 healthy subjects were instructed to execute forearm supination （FS） and forearm pronation （FP） with their right foreanns when their forearm muscles were ＂fatigue＂ or ＂relaxed＂. All surface EMG signals were recorded from their right forearm flexor during their right forearm actions. Two sets of surface EMG signals were segmented from every surface EMG signal appropriately at preparing stage and acting stage. Relative wavelet packet energy （symbolized by pnp and pna respectively at preparing stage and acting stage, n denotes the nth frequency band） of surface EMG signal firstly was calculated and then, the difference （Pn = Pna-Pnp） were gained. The results showed that Pn from some frequency bands can effectively characterize the general characteristics of surface EMG signal patterns. Compared with Pn in other frequency bands, P4, the spectral energy change from 93.75 to 125 Hz, was more appropriately regarded as the features.展开更多
A conventional Fowler flap is designed to improve the take-off and landing performances of an aircraft. Because the flight states of general aviation aircraft vary significantly. A Fowler flap with a double-sliding tr...A conventional Fowler flap is designed to improve the take-off and landing performances of an aircraft. Because the flight states of general aviation aircraft vary significantly. A Fowler flap with a double-sliding track has been designed, which is ca- pable of changing airfoil camber while cruising and climbing as well as meeting low-speed performance requirements. The aerodynamic characteristics of the variable camber Fowler flap were studied by computational simulation, and cambering was found to be beneficial for improving the lift-to-drag ratio when the lift coefficient was larger than the critical value, below which decambering was more effective; this critical value differed somewhat under different conditions. Taking the mecha- nism into account, the take-off and landing configurations were optimized on the basis of the GA （W）-1 airfoil with a 30% chord Fowler flap. Compared with reference configuration, the maximum lift coefficient of optimized take-off configuration was increased by 6.6% as well as the stalling angle and the lift-to-drag ratio were increased by 1.3° and 7.58%, respectively. Moreover, the maximum lift coefficient of the optimized landing configuration was increased by 6.3%, and the stalling angle was increased by 1.1°; however, the nose-down pitching moment of both configurations increased. Similar results were at- rained on a general aviation aircraft wing/body combination nism was established in a computer-aided design system, achieved by the double-sliding track. A 3D model of the variable-camber Fowler flap driving mecha- and the results showed that all design configurations could be展开更多
基金supported by the Advanced Research Fund for Weapons and Equipment Development of China.
文摘Based on the similarity of separation time,a similarity law optimization method for high-speed weapon delivery test is derived.The typical separation state under wind load is simulated by the numerical method.The real separation data of aircraft,separation data of previous test methods,separation data of ideal wind tunnel test of previous methods,and simulation data of the proposed optimization method are obtained.A comparison of the data shows that the method proposed can improve the performance of tracking.Similarity law optimization starts with the development of motion equations and dynamic equations in the windless state to address the problems of mismatching between vertical and horizontal displacement,and to address the problems of separation trajectory distortion caused by insufficient gravity acceleration of the scaling model of existing light model.The ejection velocity of the model is taken as a factor/vector,and is adjusted reasonably to compensate the linear displacement insufficiency caused by the insufficient vertical acceleration of the light model method,so as to ensure the matching of the vertical and horizontal displacement of the projectile,and to improve the consistency between the test results of high-speed projection and the actual separation trajectory.The optimized similarity law is applicable to many existing free-throwing modes of high-speed wind tunnels.The optimized similarity law is not affected by the ejection velocity and hanging mode of the projectile.The optimized similarity law is suitable not only for the launching of the buried ammunition compartment and external stores,but also for the test design of projectile launching and gravity separation.
基金Project supported by Railroad Ministry Foundation (2004J041)
文摘The co-operation action mechanism and model of photon-ion catalysis synergy material composed of thallium and valency-variable rare earth elements and semiconductor oxide were proposed. The radiation catalysis reactions of water and oxygen assisted by the synergy material that could largely increase electron, free radical and negative ion products were discussed. The applications of photon-ion catalysis synergy material in areas of air cleaning material, antibacterial material , healthy material and energy resource material were suggested.
文摘The effective way of finding the yarn curve shape and tension of OE(open end) yarn inside the rotor is carried out and treated by dividing the yarn curve into two parts, from which the trajectory of the yarn sliding on the navel surface is also obtained. It is pointed out that the yarn curve shape and tension will both fluctuate with the trajectory's revolving cycle inside the rotor. However, the fluctuation is not too great, so the motion can still be regarded as approximately steady for dynamic analysis.
文摘Effect of rare earth elements (RE) on erosion resistance of nitrocarburized layer of 38CrMoAl steel was investigated. The results indicate that significant improvement occurs in erosion resistance of nitrocarburized 38CrMoAl steel by introducing RE during nitrocarburizing processing as compared with conventional nitrocarburizing processing. Results of mechanical testing show that both hardness and impact toughness of RE-nitrocarburizing layer of 38CrMoAl steel increase as compared with the conventional one. Optical microscopy reveals that there is improvement in the nitrocarburized layer attributed to the introduction of RE, which results in improvement in erosion resistance. Surface morphology observation of tested samples reveals that predominantly furrow-like peelings from plastic deformation are observed for RE nitrocarburizied 38CrMoAl steel, while the furrow-like peeling with initial cross crack and large grinding peelings were observed for conventionally nitrocarburized samples.
基金supported by National Scientific and Technological Support Projects during the 11th Five-Year Plan Period (Grant No. 2006BAK02B04)Shanxi Provincial Youth Science and Technology Research Fund of China (Grant No. 2006021029)+2 种基金Shanxi Provincial Natural Science Foundation of China (Grant No. 2008011043-1)Shanxi Provincial High-tech Industrialization Project of China (Grant No20090020)Doctor Fund of Taiyuan University of Science and Technology of China (Grant No. 20092005)
文摘Steel structure system of crane deteriorates over time due to environmental effects, material fatigue, and overloading. System structural reliability and remaining service life assessment methods are developed during the few decades. But until now estimating remaining service life methods of crane steel system by reliability theory begin to develop. Safety assessment of existing steel structure system requires the development of a methodology that allows for an accurate evaluation of reliability and prediction of the remaining life. Steel structures are the supporting elements in the special equipment such as hoisting machinery. Structure reliability and remaining service life safe assessment are important for steel structures. For finding the reason which caused the failure modes （such as fatigue strength failure, stiffness failure and stability failure）, incremental loading method based on possibilistic reliability is applied into dynamic structure failure path research. Through reliability analyzing and calculating for crane, it is demonstrated that fatigue damage is the most common failure mode. Fuzzy fatigue damage accumulation theory is used for basis theory and Paris-Eadogan equations are used for mathematical modeling. All fatigue parameter values of the welding box girder of bridge cranes are determined and fatigue remaining life formulas are deduced. After field test and collecting working parameters of numerous cranes, typical fatigue load spectrum was compiled for the dangerous point of box girders used in the area. Fatigue remaining life is assessed for different types and lifting capacities. Safety for steel structure system of bridge crane is assessed by two quantitative indexs： reliability and remaining life. Therefore, the evaluation means is more comprehensive and reasonable. The example shows that the two quantitative indexs are mutually correlated. Through analyzing the 120 t-22.5 m bridge crane of a certain enterprise, a new methodology to estimate remaining service life of steel structure by possibilistic reliability theory is introduced for safety evaluation of structure system.
文摘Large quantity of negative ions and hydrogen can be produced continuously by metal ions of tourmaline under the synergy action of light, water and oxygen. In order to promote this effect, the photon-ion-catalyzed rare earth functional synergy material was prepared to simulate the nature properties of tourmaline. Its safety was discussed and an interaction model proposed. The investigation results show that the cooperation of sunlight, valency-variable rare earth element thorium includes material and photo-catalyzed TiO_2 can increase the product of free radicals and negative ions. It is safety to use thorium included rare earth or rare earth waste with radiant dose smaller than 1Gy.
文摘The properties of rare earth materials activated diesel oil such as temperature, density and hydroxylic radical were discussed. Rare earth materials including minim thorium oxide powders which had radioactivity were mainly composed of rare earth waste-residue powders. Under the radiation catalysis of rare earth materials, molecules of diesel oil can be transformed into activated molecules, the collision frequency increases among molecules, and temperature raises a little higher than usual. When temperature is higher, the interaction force between molecules is lessened, distance between molecules is shortened. The volume is increased and the density is decreased. A large amounts electrons and negative ions are produced by rare earth materials, which leads to the signals of hydroxylic radical stronger that means rare earth materials can activate diesel oil and can improve the activity of diesel oil.
基金Project supported by the National Fundamental Research Program of China (Grant No. 2013CB921804)the National Natural Science Foundation of China(Grant No. 11004065)+1 种基金the Natural Science Foundation of Guangdong Province of China (Grant Nos. 10451063101006312 and S2011040000403)the Funds of the Education Department of Anhui Province of China (Grant Nos. KJ2010A323, 2010SQRL187, and KJ2012B075)
文摘We propose a scheme to achieve a kind of nontrivial multipartite pair-wise controlled phase operation in a cavity QED setup. The operation implemented is of geometrical nature and is not sensitive to the thermal state of the cavity. In particular, we have managed to avoid the conventional dispersive coupling so that high speed gate operation is achieved which is very important in view of decoherence. We show that this multipartite pair-wise controlled phase operation makes the generation of two-dimensional cluster states very efficient.
基金supported by the Natural Science Foundation in Shanxi under Grant No. 2008012007Tackle Key Problem Program of Shanxi under Grant No. 20090321024
文摘Aiming at the problems of low-level information sharing, slow transmission and repetitive work in the designing process of product series, the internet-oriented parametric collaborative design method is proposed, in which the problems of sharing conflict and network heterogeneous in the distributed collaborative design are analyzed, and the construction method of collaborative design platforms based on PDMWorks Workgroup is put forward. Through studying the mechanism of roles distribution and function allocation and data concurrency control, the communication mechanism of internet-oriented collaborative design is formulated. On the basis of structure features of overhead travelling crane, through combining parametric variant design with collaborative design, internet-oriented parametric collaborative design system of overhead travelling crane is developed and verified through main girder design. In the paper, the internet-oriented parametric collaborative design method is proposed, aiming to solve the problems of low-level information sharing, slow transmission and repetitive work in the designing process of product series. The problems of sharing conflict and network heterogeneous in the distributed collaborative design are analyzed. The construction method of collaborative design platforms based on PDMWorks Workgroup is put forward. The communication mechanism of internet-oriented collaborative design is formulated, through studying the mechanism of roles distribution and function allocation and data concurrency control. On the basis of structure features of overhead travelling crane, through combining parametric variant design with collaborative design, internet-oriented parametric collaborative design system of overhead travelling crane is developed and verified through main girder design.
基金China 973 Project,Grant number:2005CB724303Yunnan Education Department Project,Grant number:03Y3081
文摘Spectral energy distribution of surface EMG signal is often used but difficultly and effectively control artificial limb, because the spectral energy distribution changes in the process of limb actions. In this paper, the general characteristics of surface EMG signal patterns were firstly characterized by spectral energy change. 13 healthy subjects were instructed to execute forearm supination （FS） and forearm pronation （FP） with their right foreanns when their forearm muscles were ＂fatigue＂ or ＂relaxed＂. All surface EMG signals were recorded from their right forearm flexor during their right forearm actions. Two sets of surface EMG signals were segmented from every surface EMG signal appropriately at preparing stage and acting stage. Relative wavelet packet energy （symbolized by pnp and pna respectively at preparing stage and acting stage, n denotes the nth frequency band） of surface EMG signal firstly was calculated and then, the difference （Pn = Pna-Pnp） were gained. The results showed that Pn from some frequency bands can effectively characterize the general characteristics of surface EMG signal patterns. Compared with Pn in other frequency bands, P4, the spectral energy change from 93.75 to 125 Hz, was more appropriately regarded as the features.
文摘A conventional Fowler flap is designed to improve the take-off and landing performances of an aircraft. Because the flight states of general aviation aircraft vary significantly. A Fowler flap with a double-sliding track has been designed, which is ca- pable of changing airfoil camber while cruising and climbing as well as meeting low-speed performance requirements. The aerodynamic characteristics of the variable camber Fowler flap were studied by computational simulation, and cambering was found to be beneficial for improving the lift-to-drag ratio when the lift coefficient was larger than the critical value, below which decambering was more effective; this critical value differed somewhat under different conditions. Taking the mecha- nism into account, the take-off and landing configurations were optimized on the basis of the GA （W）-1 airfoil with a 30% chord Fowler flap. Compared with reference configuration, the maximum lift coefficient of optimized take-off configuration was increased by 6.6% as well as the stalling angle and the lift-to-drag ratio were increased by 1.3° and 7.58%, respectively. Moreover, the maximum lift coefficient of the optimized landing configuration was increased by 6.3%, and the stalling angle was increased by 1.1°; however, the nose-down pitching moment of both configurations increased. Similar results were at- rained on a general aviation aircraft wing/body combination nism was established in a computer-aided design system, achieved by the double-sliding track. A 3D model of the variable-camber Fowler flap driving mecha- and the results showed that all design configurations could be
