An experimental and finite element simulation investigation are conducted to study the deformation patterns of steel targets during the penetration process of tungsten alloy long rods,as well as the influence of stren...An experimental and finite element simulation investigation are conducted to study the deformation patterns of steel targets during the penetration process of tungsten alloy long rods,as well as the influence of strength of the target on the deformation patterns.The experimental results revealed slight mass loss in the first layer of the steel target during the transient entrance phase,with an extremely negligible loss in target mass during the quasi-steady penetration phase.The results of macro-analysis,micro-analysis and simulation show that the eroded target material migrated towards the periphery of the crater,causing an increase in the target's thickness,remained within the target,instead of flowing out of the crater.Therefore,the process of long rods penetrating the metal target is considered as a process of backward extrusion.By combining the backward extrusion theory with energy conservation,a penetration depth model for long rods penetrating a metal target,taking into account both the diameter of the crater and the friction coefficient between the rod and the target,has been established.Although the model is not yet perfect,it innovatively applies the principles of solid mechanics to the study of long rod penetration.Additionally,it takes into account the friction coefficient between the rod and the target during the penetration process.Therefore,this model provides a new research direction for future studies on long rod penetration.展开更多
By applying the ＇theory of synchronization＇ from the science of complexity to studying the regional regularity of ore formation within the Nanling region of southern China, a characteristic targetpattern regional or...By applying the ＇theory of synchronization＇ from the science of complexity to studying the regional regularity of ore formation within the Nanling region of southern China, a characteristic targetpattern regional ore zonality has been discovered. During the early and late Yanshanian epoch （corresponding respectively to the Jurassic and Cretaceous periods）, two centers of ore formation emerged successively in the Nanling region; the former is mainly for rare metals （W, Sn, Mo, Bi, Nb） and one rare-earth element （La） and was generated in the Jurassic period; whereas the latter is mainly for base metals （Cu, Pb, Zn, Sb, Hg）, noble metals （Au, Ag）, and one radioactive element （U） and was generated in the Cretaceous period. Centers of ore formation were brought about by interface dynamics respectively at the Qitianling and Jiuyishan districts in southern Hunan Province. The characteristic giant nonlinear target-pattern regional ore zonality was generated by spatio-temporal synchronization process of the Nanling complex metallogenic system. It induced the collective dynamics and cooperative behavior of the system and displayed the configuration of the regional ore zonality. Then dynamical clustering transformed the configuration into rudimentary ordered coherent structures. Phase dynamics eventually defined the spatio-temporal structures of the target-pattern regional ore zonality and determined their localization and distribution. A new methodology for revealing regional ore zonality is developed, which will encourage further investigation of the formation of deep-seated ore resources and the onset of large-scale mineralization.展开更多
By applying the ＇theory of synchronization＇ from the science of complexity to studying the regional regularity of ore formation within the Nanling region of southern China, a characteristic targetpattern regional or...By applying the ＇theory of synchronization＇ from the science of complexity to studying the regional regularity of ore formation within the Nanling region of southern China, a characteristic targetpattern regional ore zonality has been discovered. During the early and late Yanshanian epoch （corresponding respectively to the Jurassic and Cretaceous periods）, two centers of ore formation emerged successively in the Nanling region; the former is mainly for rare metals （W, Sn, Mo, Bi, Nb） and one rare-earth element （La） and was generated in the Jurassic period; whereas the latter is mainly for base metals （Cu, Pb, Zn, Sb, Hg）, noble metals （Au, Ag）, and one radioactive element （U） and was generated in the Cretaceous period. Centers of ore formation were brought about by interface dynamics respectively at the Qitianling and Jiuyishan districts in southern Hunan province. The characteristic giant nonlinear target-pattern regional ore zonality was generated by spatio-temporal synchronization process of the Nanling complex metallogenic system. It induced the collective dynamics and cooperative behavior of the system and displayed the configuration of the regional ore zonality. Then dynamical clustering transformed the configuration into rudimentary ordered coherent structures. Phase dynamics eventually defined the spatio-temporal structures of the target-pattern regional ore zonality and determined their localization and distribution. A new methodology for revealing regional ore zonality is developed, which will encourage further investigation of the formation of deep-seated ore resources and the onset of laree-scale mineralization.展开更多
By applying the ＇theory of synchronization＇ from the science of complexity to studying the regional regularity of ore formation within the Nanling region of South China,a characteristic target-pattern regional ore z...By applying the ＇theory of synchronization＇ from the science of complexity to studying the regional regularity of ore formation within the Nanling region of South China,a characteristic target-pattern regional ore zonality has been discovered.During the early and late Yanshanian epoch （corresponding respectively to the Jurassic and Cretaceous periods）,two centers of ore formation emerged successively in the Nanling region;the former is mainly for rare metals（W,Sn,Mo,Bi,Nb） and one rare-earth element（La） and was generated in the Jurassic period;whereas the latter is mainly for base metals （Cu,Pb,Zn,Sb,Hg）,noble metals（Au,Ag）,and one radioactive element（U） and was generated in the Cretaceous period.Centers of ore formation were brought about by interface dynamics respectively at the Qitianling and Jiuyishan districts in southern Hunan Province.The characteristic giant nonlinear target-pattern regional ore zonality was generated respectively from the two centers of ore formation by the spatio-temporal synchronization process of the Nanling complex metallogenic system.It induced the collective dynamics and cooperative behavior of the system and displayed the configuration of the regional ore zonality.Then dynamical clustering transformed the configuration into rudimentary ordered coherent structures.Phase dynamics eventually defined the spatio-temporal structures of the target-pattern regional ore zonality and determined their localization and distribution.The integral successive processes of synchronization-dynamical clustering-phase dynamics accomplished the regional ore zonality by way of ＂multiple field dynamics＂ of spatio-temporal superposition of multiple coupled pulsatory solitary wave trains of the zonal sequences of different ores.A new methodology for revealing regional ore zonality is developed,which will encourage further investigation of the formation of deep-seated ore resources and the onset of large-scale mineralization.展开更多
In this paper, we study periodic waves in reaction-diffusion systems with limit cycle kinetics and weak diffusion. The results are based on the analysis of a nonlinear partial differential equation which is derived fr...In this paper, we study periodic waves in reaction-diffusion systems with limit cycle kinetics and weak diffusion. The results are based on the analysis of a nonlinear partial differential equation which is derived from singular perturbation techniques. We obtain the first order approximation expression of the dispersion curve for periodic wave trains and then show that in the generic case of limit cycle kinetics there is a one parameter family of target patterns and the rotating spiral waves of Archimedian type exist. Finally, we apply these results to the general λ-ω systems.展开更多
Despite the growing body of work on molecular components required for regenerative repair,we still lack a deep understanding of the ability of some animal species to regenerate their appropriate complex anatomical str...Despite the growing body of work on molecular components required for regenerative repair,we still lack a deep understanding of the ability of some animal species to regenerate their appropriate complex anatomical structure following damage.A key question is how regenerating systems know when to stop growth and remodeling-what mechanisms implement recognition of correct morphology that signals a stop condition？In this work,we review two conceptual models of pattern regeneration that implement a kind of pattern memory.In the first one,all cells communicate with each other and keep the value of the total signal received from the other cells.If a part of the pattern is amputated,the signal distribution changes.The difference fromthe original signal distribution stimulates cell proliferation and leads to pattern regeneration,in effect implementing an error minimization process that uses signaling memory to achieve pattern correction.In the second model,we consider a more complex pattern organization with different cell types.Each tissue contains a central（coordinator）cell that controls the tissue and communicates with the other central cells.Each of them keeps memory about the signals received from other central cells.The values of these signals depend on the mutual cell location,and the memory allows regeneration of the structure when it is modified.The purpose of these models is to suggest possible mechanisms of pattern regeneration operating on the basis of cell memory which are compatible with diverse molecular implementation mechanisms within specific organisms.展开更多
Threat-judgment is a complicated fuzzy inference problem. Up to now no relevant unified theory and measur-ing standard have been developed. It is very difficult to establish a threat-judgment model with high reliabili...Threat-judgment is a complicated fuzzy inference problem. Up to now no relevant unified theory and measur-ing standard have been developed. It is very difficult to establish a threat-judgment model with high reliability in the airdefense system for the naval warships. Air target threat level judgment is an important component in naval warship com-bat command decision-making systems. According to the threat level judgment of air targets during the air defense of sin-gle naval warship, a fuzzy pattern recognition model for judging the threat from air targets is established. Then an algo-rithm for identifying the parameters in the model is presented. The model has an adaptive feature and can dynamicallyupdate its parameters according to the state change of the attacking targets and the environment. The method presentedhere can be used for the air defense system threat judgment in the naval warships.展开更多
The distribution function of the target moving in constant velocity and linear course and its meeting condition to the searcher are analyzed.Another proof method for spiral search pattern is presented and the mathemat...The distribution function of the target moving in constant velocity and linear course and its meeting condition to the searcher are analyzed.Another proof method for spiral search pattern is presented and the mathematic model of the target possible position is established when performing the linear search.Base on them,the wrong idea about the spiral search pattern can be展开更多
An algorithm for detecting moving IR point target in complex background is proposed, which is based on the Reverse Phase Feature of Neighborhood （RPFN） of target in difference between neighbor frame images that two ...An algorithm for detecting moving IR point target in complex background is proposed, which is based on the Reverse Phase Feature of Neighborhood （RPFN） of target in difference between neighbor frame images that two positions of the target in the difference image are near and the gray values of them are close to in absolute value but with inverse sign. Firstly, pairs of points with RPFN are detected in the difference image between neighbor frame images, with which a virtual vector graph is made, and then the moving point target can be detected by the vectors＇ sequence cumulated in vector graphs. In addition, a theorem for the convergence of detection of target contrail by this algorithm is given and proved so as to afford a solid guarantee for practical applications of the algorithm proposed in this paper. Finally, some simulation results with 1000 frames from 10 typical images in complex background show that moving point targets with SNR not lower than 1.5 can be detected effectively.展开更多
A new method of effectiveness evaluation of weapon systems is set up by improving the formula of approaching degree. According to the grey target theory of grey system theory, the patterns of the weapon systems to be ...A new method of effectiveness evaluation of weapon systems is set up by improving the formula of approaching degree. According to the grey target theory of grey system theory, the patterns of the weapon systems to be evaluated are formed with the main tactical and technical performance indices of these weapon systems, thereby the standard pattern of these patterns is determined. By solving the approaching degree of patterns to their standard one and making a comparison among them, the evaluation results can be obtained.展开更多
A novel modified four path method (FPM) is presented for calculating coupling field of super-low altitude aircraft target. Based on the hybrid method PO + MEC (Physical Optics and Method of Equivalent Currents), the a...A novel modified four path method (FPM) is presented for calculating coupling field of super-low altitude aircraft target. Based on the hybrid method PO + MEC (Physical Optics and Method of Equivalent Currents), the antenna radiation pattern is introduced to consider the multipath interference from side lobe of seeker. The modified FPM is used to calculate the coupling field from super-low altitude aircraft target above different terrestrial environments. The curves of scattering coefficient are analyzed. The influences of height of target, root mean square (RMS), and incident angle on coupling field characteristics are discussed. The simulation results can be used for reference in detection for super-low altitude target and optimization for radar system.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.12102201,U2341244).
文摘An experimental and finite element simulation investigation are conducted to study the deformation patterns of steel targets during the penetration process of tungsten alloy long rods,as well as the influence of strength of the target on the deformation patterns.The experimental results revealed slight mass loss in the first layer of the steel target during the transient entrance phase,with an extremely negligible loss in target mass during the quasi-steady penetration phase.The results of macro-analysis,micro-analysis and simulation show that the eroded target material migrated towards the periphery of the crater,causing an increase in the target's thickness,remained within the target,instead of flowing out of the crater.Therefore,the process of long rods penetrating the metal target is considered as a process of backward extrusion.By combining the backward extrusion theory with energy conservation,a penetration depth model for long rods penetrating a metal target,taking into account both the diameter of the crater and the friction coefficient between the rod and the target,has been established.Although the model is not yet perfect,it innovatively applies the principles of solid mechanics to the study of long rod penetration.Additionally,it takes into account the friction coefficient between the rod and the target during the penetration process.Therefore,this model provides a new research direction for future studies on long rod penetration.
基金supported by China Geological Survey Grants No. 1212010561603(2005)
文摘By applying the ＇theory of synchronization＇ from the science of complexity to studying the regional regularity of ore formation within the Nanling region of southern China, a characteristic targetpattern regional ore zonality has been discovered. During the early and late Yanshanian epoch （corresponding respectively to the Jurassic and Cretaceous periods）, two centers of ore formation emerged successively in the Nanling region; the former is mainly for rare metals （W, Sn, Mo, Bi, Nb） and one rare-earth element （La） and was generated in the Jurassic period; whereas the latter is mainly for base metals （Cu, Pb, Zn, Sb, Hg）, noble metals （Au, Ag）, and one radioactive element （U） and was generated in the Cretaceous period. Centers of ore formation were brought about by interface dynamics respectively at the Qitianling and Jiuyishan districts in southern Hunan Province. The characteristic giant nonlinear target-pattern regional ore zonality was generated by spatio-temporal synchronization process of the Nanling complex metallogenic system. It induced the collective dynamics and cooperative behavior of the system and displayed the configuration of the regional ore zonality. Then dynamical clustering transformed the configuration into rudimentary ordered coherent structures. Phase dynamics eventually defined the spatio-temporal structures of the target-pattern regional ore zonality and determined their localization and distribution. A new methodology for revealing regional ore zonality is developed, which will encourage further investigation of the formation of deep-seated ore resources and the onset of large-scale mineralization.
基金supported by China Geological Survey grants 1212010561603(2005)
文摘By applying the ＇theory of synchronization＇ from the science of complexity to studying the regional regularity of ore formation within the Nanling region of southern China, a characteristic targetpattern regional ore zonality has been discovered. During the early and late Yanshanian epoch （corresponding respectively to the Jurassic and Cretaceous periods）, two centers of ore formation emerged successively in the Nanling region; the former is mainly for rare metals （W, Sn, Mo, Bi, Nb） and one rare-earth element （La） and was generated in the Jurassic period; whereas the latter is mainly for base metals （Cu, Pb, Zn, Sb, Hg）, noble metals （Au, Ag）, and one radioactive element （U） and was generated in the Cretaceous period. Centers of ore formation were brought about by interface dynamics respectively at the Qitianling and Jiuyishan districts in southern Hunan province. The characteristic giant nonlinear target-pattern regional ore zonality was generated by spatio-temporal synchronization process of the Nanling complex metallogenic system. It induced the collective dynamics and cooperative behavior of the system and displayed the configuration of the regional ore zonality. Then dynamical clustering transformed the configuration into rudimentary ordered coherent structures. Phase dynamics eventually defined the spatio-temporal structures of the target-pattern regional ore zonality and determined their localization and distribution. A new methodology for revealing regional ore zonality is developed, which will encourage further investigation of the formation of deep-seated ore resources and the onset of laree-scale mineralization.
基金supported by China Geological Survey grant nos 1212010561603 and 1212011121101(2005)
文摘By applying the ＇theory of synchronization＇ from the science of complexity to studying the regional regularity of ore formation within the Nanling region of South China,a characteristic target-pattern regional ore zonality has been discovered.During the early and late Yanshanian epoch （corresponding respectively to the Jurassic and Cretaceous periods）,two centers of ore formation emerged successively in the Nanling region;the former is mainly for rare metals（W,Sn,Mo,Bi,Nb） and one rare-earth element（La） and was generated in the Jurassic period;whereas the latter is mainly for base metals （Cu,Pb,Zn,Sb,Hg）,noble metals（Au,Ag）,and one radioactive element（U） and was generated in the Cretaceous period.Centers of ore formation were brought about by interface dynamics respectively at the Qitianling and Jiuyishan districts in southern Hunan Province.The characteristic giant nonlinear target-pattern regional ore zonality was generated respectively from the two centers of ore formation by the spatio-temporal synchronization process of the Nanling complex metallogenic system.It induced the collective dynamics and cooperative behavior of the system and displayed the configuration of the regional ore zonality.Then dynamical clustering transformed the configuration into rudimentary ordered coherent structures.Phase dynamics eventually defined the spatio-temporal structures of the target-pattern regional ore zonality and determined their localization and distribution.The integral successive processes of synchronization-dynamical clustering-phase dynamics accomplished the regional ore zonality by way of ＂multiple field dynamics＂ of spatio-temporal superposition of multiple coupled pulsatory solitary wave trains of the zonal sequences of different ores.A new methodology for revealing regional ore zonality is developed,which will encourage further investigation of the formation of deep-seated ore resources and the onset of large-scale mineralization.
文摘In this paper, we study periodic waves in reaction-diffusion systems with limit cycle kinetics and weak diffusion. The results are based on the analysis of a nonlinear partial differential equation which is derived from singular perturbation techniques. We obtain the first order approximation expression of the dispersion curve for periodic wave trains and then show that in the generic case of limit cycle kinetics there is a one parameter family of target patterns and the rotating spiral waves of Archimedian type exist. Finally, we apply these results to the general λ-ω systems.
基金support of the G.Harold and Leila Y.Mathers Charitable Foundationthe Templeton World Charity Foundation(TWCF0089/AB55)the W.M.Keck Foundation
文摘Despite the growing body of work on molecular components required for regenerative repair,we still lack a deep understanding of the ability of some animal species to regenerate their appropriate complex anatomical structure following damage.A key question is how regenerating systems know when to stop growth and remodeling-what mechanisms implement recognition of correct morphology that signals a stop condition？In this work,we review two conceptual models of pattern regeneration that implement a kind of pattern memory.In the first one,all cells communicate with each other and keep the value of the total signal received from the other cells.If a part of the pattern is amputated,the signal distribution changes.The difference fromthe original signal distribution stimulates cell proliferation and leads to pattern regeneration,in effect implementing an error minimization process that uses signaling memory to achieve pattern correction.In the second model,we consider a more complex pattern organization with different cell types.Each tissue contains a central（coordinator）cell that controls the tissue and communicates with the other central cells.Each of them keeps memory about the signals received from other central cells.The values of these signals depend on the mutual cell location,and the memory allows regeneration of the structure when it is modified.The purpose of these models is to suggest possible mechanisms of pattern regeneration operating on the basis of cell memory which are compatible with diverse molecular implementation mechanisms within specific organisms.
基金This project was supported by the National Defense Foundation of China(40108070103)
文摘Threat-judgment is a complicated fuzzy inference problem. Up to now no relevant unified theory and measur-ing standard have been developed. It is very difficult to establish a threat-judgment model with high reliability in the airdefense system for the naval warships. Air target threat level judgment is an important component in naval warship com-bat command decision-making systems. According to the threat level judgment of air targets during the air defense of sin-gle naval warship, a fuzzy pattern recognition model for judging the threat from air targets is established. Then an algo-rithm for identifying the parameters in the model is presented. The model has an adaptive feature and can dynamicallyupdate its parameters according to the state change of the attacking targets and the environment. The method presentedhere can be used for the air defense system threat judgment in the naval warships.
文摘The distribution function of the target moving in constant velocity and linear course and its meeting condition to the searcher are analyzed.Another proof method for spiral search pattern is presented and the mathematic model of the target possible position is established when performing the linear search.Base on them,the wrong idea about the spiral search pattern can be
文摘An algorithm for detecting moving IR point target in complex background is proposed, which is based on the Reverse Phase Feature of Neighborhood （RPFN） of target in difference between neighbor frame images that two positions of the target in the difference image are near and the gray values of them are close to in absolute value but with inverse sign. Firstly, pairs of points with RPFN are detected in the difference image between neighbor frame images, with which a virtual vector graph is made, and then the moving point target can be detected by the vectors＇ sequence cumulated in vector graphs. In addition, a theorem for the convergence of detection of target contrail by this algorithm is given and proved so as to afford a solid guarantee for practical applications of the algorithm proposed in this paper. Finally, some simulation results with 1000 frames from 10 typical images in complex background show that moving point targets with SNR not lower than 1.5 can be detected effectively.
文摘A new method of effectiveness evaluation of weapon systems is set up by improving the formula of approaching degree. According to the grey target theory of grey system theory, the patterns of the weapon systems to be evaluated are formed with the main tactical and technical performance indices of these weapon systems, thereby the standard pattern of these patterns is determined. By solving the approaching degree of patterns to their standard one and making a comparison among them, the evaluation results can be obtained.
文摘A novel modified four path method (FPM) is presented for calculating coupling field of super-low altitude aircraft target. Based on the hybrid method PO + MEC (Physical Optics and Method of Equivalent Currents), the antenna radiation pattern is introduced to consider the multipath interference from side lobe of seeker. The modified FPM is used to calculate the coupling field from super-low altitude aircraft target above different terrestrial environments. The curves of scattering coefficient are analyzed. The influences of height of target, root mean square (RMS), and incident angle on coupling field characteristics are discussed. The simulation results can be used for reference in detection for super-low altitude target and optimization for radar system.
