To obtain higher accurate position estimates, the stochastic model is estimated by using residual of observations, hence, the stochastic model describes the noise and bias in measurements more realistically. By using ...To obtain higher accurate position estimates, the stochastic model is estimated by using residual of observations, hence, the stochastic model describes the noise and bias in measurements more realistically. By using GPS data and broadcast ephemeris, the numerical results indicating the accurate position estimates at sub-meter level are obtainable.展开更多
A compressed sensing (CS) based channel estimation algorithm is proposed in the fast moving environment. A sparse basis expansion channel model in both time and frequency domain is given.Pilots are placed according ...A compressed sensing (CS) based channel estimation algorithm is proposed in the fast moving environment. A sparse basis expansion channel model in both time and frequency domain is given.Pilots are placed according to a novel random unit pilot matrix (RUPM) to measure the delay- Doppler sparse channel. The sparse channels are recovered by an extension group orthogonal matching pursuit (GOMP) algorithm, enjoying the diversity gain from multi-symbol processing. The relatively nonzero channel coefficients are estimated from a very limited number of pilots at a sampling rate significantly below the Nyquist rate. The simulation results show that the new channel estimator can provide a considerable performance improvement for the fast fading channels. Three significant reductions are achieved in the required number of pilots, memory requirements and computational complexity.展开更多
The possible collapse of different circumstances is derived with the help of the limit analysis theory.Analytical equations related to collapsing mechanisms in deep tunnel with smooth three-centered arc cross sections...The possible collapse of different circumstances is derived with the help of the limit analysis theory.Analytical equations related to collapsing mechanisms in deep tunnel with smooth three-centered arc cross sections are derived on the basis of Hoek-Brown failure criterion and upper bound limit analysis.The pore water pressure is considered in the analysis,as a work rate of external force.Numerical results about the shape of detaching curve and the weight of collapsing block per unit length corresponding to different parameters are obtained with the help of mathematical software.The shapes of collapsing block are drawn with respected to different parameters.Furthermore,the effects of different parameters on the shape of detaching curve and the weight of the collapsing block are discussed.展开更多
In the reform of government organizations and institutions of China, we put forward the establishment of personal account system in occupational pension, and the introduction of the "account" management model of the...In the reform of government organizations and institutions of China, we put forward the establishment of personal account system in occupational pension, and the introduction of the "account" management model of the non real account accumulation. This paper analyzes the current situation of personal accounts in our country, and puts forward that the account rate of bank deposit can not resist inflation, and can not reflect the real return rate of China's pension funds, which is not conducive to the preservation and appreciation of personal account funds. On the basis of the above, the paper puts forward that the account rate should not only consider the level of economic development and inflation, but also to adapt to the financial payment ability, and establish the personal account risk reserve fund system and other improvement measures, and strive to achieve the sustainable development of the personal account system.展开更多
A system for mobile robot localization and navigation was presented.With the proposed system,the robot can be located and navigated by a single landmark in a single image.And the navigation mode may be following-track...A system for mobile robot localization and navigation was presented.With the proposed system,the robot can be located and navigated by a single landmark in a single image.And the navigation mode may be following-track,teaching and playback,or programming.The basic idea is that the system computes the differences between the expected and the recognized position at each time and then controls the robot in a direction to reduce those differences.To minimize the robot sensor equipment,only one omnidirectional camera was used.Experiments in disturbing environments show that the presented algorithm is robust and easy to implement,without camera rectification.The rootmean-square error(RMSE) of localization is 1.4,cm,and the navigation error in teaching and playback is within 10,cm.展开更多
The merger of the pension not only in relation to the social justice, but also the relationship between the construction of social security system, pensions merger is beyond doubt. Pension dual track the biggest drawb...The merger of the pension not only in relation to the social justice, but also the relationship between the construction of social security system, pensions merger is beyond doubt. Pension dual track the biggest drawback is that a significant loss of fairness, the gap between different groups of pension is too wide, causing social conflicts. The merger of the pension has be imperative. Therefore, it is necessary to establish and perfect the system of the civil service pension insurance legal mandatory occupational pension system, strengthen the basic social pension, broaden the channels for pension investment, reform organs and institutions pension system and pension system Retbrm and civil service pay rise, in order to promote the reform of the civil service pension system. The merger of the pension reform is scientific and reasonable, healthy and orderly and can achieve a smooth transition.展开更多
Suction boxes are used in the paper industry to simultaneously drain a pulp suspension and form a fibre mat (or filter cake). This research addresses the modelling of fibre deposition in the forming unit of an indus...Suction boxes are used in the paper industry to simultaneously drain a pulp suspension and form a fibre mat (or filter cake). This research addresses the modelling of fibre deposition in the forming unit of an industrial papermachine, assuming a filtration process, and that of the flowing suspension drained through the building fibre mat and the wire on a suction box. From experimental data of the cumulative drained V volume, per unit surface area, for two vacuum pressures △P and 6 dwell times t, an extension of the classical law (t/V) versus V is proposed, validated and applied. This relation enables determining the average specific filtration resistance of the fibre mat over the box and the mass of solids deposited before and over the suction box. The model obtained is as precise as 1% and can be used to limit and reduce the energy consumption of drainage vacuum assisted devices such as suction boxes in the forming unit of industrial papermachines.展开更多
Equilibrium function in the cerebellum (vestibulo-cerebellar system) can deteriorate under the influence of alcohol. In the Romberg posture, the center of gravity, which was measured every 50 ms by stabilometry, app...Equilibrium function in the cerebellum (vestibulo-cerebellar system) can deteriorate under the influence of alcohol. In the Romberg posture, the center of gravity, which was measured every 50 ms by stabilometry, appeared to shift with alcohol ingestion. In the previous study, a locus in the center of gravity (stabilogram) was converted to values of statistical indices such as area of sway, total locus length, sparse density, and locus length per unit area, although these indices could not always distinguish between the stabilograms sampled from seven healthy young males in sober and intoxicated states. This measurement was made with an AMTI force plate. In this study, "translation error" was estimated in a d-dimensional embedding space in order to compare stabilograms recorded before and after the ingestion of doubly diluted brandy in 30 s (1 ≤ d ≤ 10). The authors succeeded in validating stochastic differential equations as a mathematical model of the body sway. Although the postural control system shows different patterns in the lateral and anterior-posterior directions, the randomness in the model was preserved after alcohol intake and significantly increased in the medial/lateral direction. Visual information referred by the postural conlrol system when standing might be interfered by the effects of intoxication, which was regarded as disturbance. The possibility of detecting alcohol-ingestion-induced reduction of the equilibrium function and its recovery process are also suggested in this paper. This method is considered to be useful to diagnose the disorders of the vestibulo-cerebellar system.展开更多
The random Dirichlet type functions on the unit ball of Cn are studied. Sufficient conditions of the multipliers of Dμ for 0 < μ≤1, if n = 1 or 0 < μ < 2 if n > 1 are given. The smoothness of random Di...The random Dirichlet type functions on the unit ball of Cn are studied. Sufficient conditions of the multipliers of Dμ for 0 < μ≤1, if n = 1 or 0 < μ < 2 if n > 1 are given. The smoothness of random Dirichlet type functions is discussed.展开更多
This paper studies a maintenance model for an one-unit degenerative system with multiple failure states based on the proportional hazards and proportional reversed hazards models. The authors investigate how the varia...This paper studies a maintenance model for an one-unit degenerative system with multiple failure states based on the proportional hazards and proportional reversed hazards models. The authors investigate how the variation of system configuration parameters have an impact on both operating and repair times and hence the system performance. Furthermore, the authors also derive the explicit expression for the long-run average cost per unit time. An algorithm to locate the optimal number of repairs in a renewal cycle is discussed as well.展开更多
Based on the theoretical model of anion coordination polyhedron growth units, the growth mechanism of the basic magnesium chloride whisker was discussed in this paper.It was found that the basic magnesium chloride whi...Based on the theoretical model of anion coordination polyhedron growth units, the growth mechanism of the basic magnesium chloride whisker was discussed in this paper.It was found that the basic magnesium chloride whisker habits were related to the different environments in which anion coordination polyhedra grew. The growth units of basic magnesium chloride whiskers are [Mg - (OH) 4]2 -and [Mg - Cl 4]2 -. The growth process is the incorporation process of growth units. Growth units will have different incorporations and orientations caused by different system characters or heating. Furthermore, the formation mechanism of basic magnesium chloride whiskers was also interpreted using anion coordination polyhedron growth units.展开更多
Lowering the operating temperature of solid oxide fuel cells(SOFCs)has extensively stimulated the development of new oxide ion conductors.Here,inspired by the structural commonalities of oxide ion conductors,the inabi...Lowering the operating temperature of solid oxide fuel cells(SOFCs)has extensively stimulated the development of new oxide ion conductors.Here,inspired by the structural commonalities of oxide ion conductors,the inability to accommodate oxygen vacancies in the rigid,isolated,3-fold tetrahedral rings of SrSi/GeO_(3)-based materials,and the considerable flexibility of BO_(n) polyhedra in terms of coordination number,rotation,deformation,and linkage,we report the first borate-base family of oxide ion conductors,(Gd/Y)_(1−x)Zn_(x)BO_(3−0.5x),through combined computational prediction and experimental verification.The oxygen vacancies in(Gd/Y)BO_(3)can be accommodated by forming B_(3)O_(8)units in isolated,3-fold,tetrahedral rings of B_(3)O_(9)and transported through a cooperative mechanism of oxygen exchange between the B_(3)O_(9)and B_(3)O_(8)units,which is assisted by the intermediate opening and extending of these units.This study opens a new scientific field of the borate system for designing and discovering oxide ion conductors.展开更多
Objective: To investigate stretch-induced electrophysiological changes in chronically infarcted hearts and the effect of streptomycin (SM) on these changes in vivo. Methods: Sixty Wistar rats were divided randomly...Objective: To investigate stretch-induced electrophysiological changes in chronically infarcted hearts and the effect of streptomycin (SM) on these changes in vivo. Methods: Sixty Wistar rats were divided randomly into four groups: a control group (n=15), an SM group (n=15), a myocardial infarction (MI) group (n=15), and an MI+SM group (n=15). Chronic MI was obtained by ligating the left anterior descending branch (LAD) of rat hearts for eight weeks. The in vivo blockade of stretch-activated ion channels (SACs) was achieved by intramuscular injection of SM (180 mg/(kg·d)) for seven days after operation. The hearts were stretched for 5 s by occlusion of the aortic arch. Suction electrodes were placed on the anterior wall of left ventricle to record the monophasic action potential (MAP). The effect of stretching was examined by assessing the 90% monophasic action potential duration (MAPD90), premature ventricular beats (PVBs), and ventricular tachycardia (VT). Results: The MAPD90 decreased during stretching in both the control (from (50.27±5.61) ms to (46.27±4.51) ms, P〈0.05) and MI groups (from (65.47±6.38) ms to (57.47±5.76 ms), P〈0.01 ). SM inhibited the decrease in MAPD90 during inflation ((46.27±4.51) ms vs. (49.53±3.52) ms, P〈0.05 in normal hearts; (57.47±5.76) ms vs. (61.87±5.33) ms, P〈0.05 in MI hearts). The occurrence of PVBs and VT in the MI group increased compared with that in the control group (PVB: 7.93±1.66 vs. 1.80±0.86, P〈0.01; VT: 7 vs. 1, P〈0.05). SM decreased the occurrence of PVBs in both normal and MI hearts (0.93±0.59 vs. 1.80±0.86 in normal hearts, P〈0.05; 5.40±1.18 vs. 7.93±1.66 in MI hearts, P〈0.01). Conclusions: Stretch-induced MAPD90 changes and arrhythmias were observed in chronically infarcted myocardium. The use of SM in vivo decreased the incidence of PVBs but not of VT. This suggests that SACs may be involved in mechanoelectric feedback (MEF), but that there might be other mechanisms involved in causing VT in chronic MI.展开更多
基金Supported by the National 863 Program of China (No.2006AA12Z325) and the National Natural Science Foundation of China (No.40274005).
文摘To obtain higher accurate position estimates, the stochastic model is estimated by using residual of observations, hence, the stochastic model describes the noise and bias in measurements more realistically. By using GPS data and broadcast ephemeris, the numerical results indicating the accurate position estimates at sub-meter level are obtainable.
基金Supported by the National Natural Science Foundation of China ( No. 60972056 ), the Innovation Foundation of Shanghai Education Committee ( No. 09ZZ89) and Shanghai Leading Academic Discipline Project and STCSM ( No.S30108, 08DZ2231100 ).
文摘A compressed sensing (CS) based channel estimation algorithm is proposed in the fast moving environment. A sparse basis expansion channel model in both time and frequency domain is given.Pilots are placed according to a novel random unit pilot matrix (RUPM) to measure the delay- Doppler sparse channel. The sparse channels are recovered by an extension group orthogonal matching pursuit (GOMP) algorithm, enjoying the diversity gain from multi-symbol processing. The relatively nonzero channel coefficients are estimated from a very limited number of pilots at a sampling rate significantly below the Nyquist rate. The simulation results show that the new channel estimator can provide a considerable performance improvement for the fast fading channels. Three significant reductions are achieved in the required number of pilots, memory requirements and computational complexity.
基金Project(2013CB036004)supported by Basic Research Program of ChinaProjects(51378510,41302226)supported by National Natural Science Foundation of ChinaProject(2016zzts062)supported by Doctorial Innovation Foundation of Central South University,China
文摘The possible collapse of different circumstances is derived with the help of the limit analysis theory.Analytical equations related to collapsing mechanisms in deep tunnel with smooth three-centered arc cross sections are derived on the basis of Hoek-Brown failure criterion and upper bound limit analysis.The pore water pressure is considered in the analysis,as a work rate of external force.Numerical results about the shape of detaching curve and the weight of collapsing block per unit length corresponding to different parameters are obtained with the help of mathematical software.The shapes of collapsing block are drawn with respected to different parameters.Furthermore,the effects of different parameters on the shape of detaching curve and the weight of the collapsing block are discussed.
文摘In the reform of government organizations and institutions of China, we put forward the establishment of personal account system in occupational pension, and the introduction of the "account" management model of the non real account accumulation. This paper analyzes the current situation of personal accounts in our country, and puts forward that the account rate of bank deposit can not resist inflation, and can not reflect the real return rate of China's pension funds, which is not conducive to the preservation and appreciation of personal account funds. On the basis of the above, the paper puts forward that the account rate should not only consider the level of economic development and inflation, but also to adapt to the financial payment ability, and establish the personal account risk reserve fund system and other improvement measures, and strive to achieve the sustainable development of the personal account system.
基金Supported by National Natural Science Foundation of China (No. 31000422 and No. 61201081)Tianjin Municipal Education Commission(No.20110829)Tianjin Science and Technology Committee(No. 10JCZDJC22800)
文摘A system for mobile robot localization and navigation was presented.With the proposed system,the robot can be located and navigated by a single landmark in a single image.And the navigation mode may be following-track,teaching and playback,or programming.The basic idea is that the system computes the differences between the expected and the recognized position at each time and then controls the robot in a direction to reduce those differences.To minimize the robot sensor equipment,only one omnidirectional camera was used.Experiments in disturbing environments show that the presented algorithm is robust and easy to implement,without camera rectification.The rootmean-square error(RMSE) of localization is 1.4,cm,and the navigation error in teaching and playback is within 10,cm.
文摘The merger of the pension not only in relation to the social justice, but also the relationship between the construction of social security system, pensions merger is beyond doubt. Pension dual track the biggest drawback is that a significant loss of fairness, the gap between different groups of pension is too wide, causing social conflicts. The merger of the pension has be imperative. Therefore, it is necessary to establish and perfect the system of the civil service pension insurance legal mandatory occupational pension system, strengthen the basic social pension, broaden the channels for pension investment, reform organs and institutions pension system and pension system Retbrm and civil service pay rise, in order to promote the reform of the civil service pension system. The merger of the pension reform is scientific and reasonable, healthy and orderly and can achieve a smooth transition.
文摘Suction boxes are used in the paper industry to simultaneously drain a pulp suspension and form a fibre mat (or filter cake). This research addresses the modelling of fibre deposition in the forming unit of an industrial papermachine, assuming a filtration process, and that of the flowing suspension drained through the building fibre mat and the wire on a suction box. From experimental data of the cumulative drained V volume, per unit surface area, for two vacuum pressures △P and 6 dwell times t, an extension of the classical law (t/V) versus V is proposed, validated and applied. This relation enables determining the average specific filtration resistance of the fibre mat over the box and the mass of solids deposited before and over the suction box. The model obtained is as precise as 1% and can be used to limit and reduce the energy consumption of drainage vacuum assisted devices such as suction boxes in the forming unit of industrial papermachines.
文摘Equilibrium function in the cerebellum (vestibulo-cerebellar system) can deteriorate under the influence of alcohol. In the Romberg posture, the center of gravity, which was measured every 50 ms by stabilometry, appeared to shift with alcohol ingestion. In the previous study, a locus in the center of gravity (stabilogram) was converted to values of statistical indices such as area of sway, total locus length, sparse density, and locus length per unit area, although these indices could not always distinguish between the stabilograms sampled from seven healthy young males in sober and intoxicated states. This measurement was made with an AMTI force plate. In this study, "translation error" was estimated in a d-dimensional embedding space in order to compare stabilograms recorded before and after the ingestion of doubly diluted brandy in 30 s (1 ≤ d ≤ 10). The authors succeeded in validating stochastic differential equations as a mathematical model of the body sway. Although the postural control system shows different patterns in the lateral and anterior-posterior directions, the randomness in the model was preserved after alcohol intake and significantly increased in the medial/lateral direction. Visual information referred by the postural conlrol system when standing might be interfered by the effects of intoxication, which was regarded as disturbance. The possibility of detecting alcohol-ingestion-induced reduction of the equilibrium function and its recovery process are also suggested in this paper. This method is considered to be useful to diagnose the disorders of the vestibulo-cerebellar system.
文摘The random Dirichlet type functions on the unit ball of Cn are studied. Sufficient conditions of the multipliers of Dμ for 0 < μ≤1, if n = 1 or 0 < μ < 2 if n > 1 are given. The smoothness of random Dirichlet type functions is discussed.
基金supported by the National Natural Science Foundation of China under Grant No.11422109
文摘This paper studies a maintenance model for an one-unit degenerative system with multiple failure states based on the proportional hazards and proportional reversed hazards models. The authors investigate how the variation of system configuration parameters have an impact on both operating and repair times and hence the system performance. Furthermore, the authors also derive the explicit expression for the long-run average cost per unit time. An algorithm to locate the optimal number of repairs in a renewal cycle is discussed as well.
基金supported by the National Natural Science Foundation of China (Grant Nos. 40776071, 40976074)
文摘Based on the theoretical model of anion coordination polyhedron growth units, the growth mechanism of the basic magnesium chloride whisker was discussed in this paper.It was found that the basic magnesium chloride whisker habits were related to the different environments in which anion coordination polyhedra grew. The growth units of basic magnesium chloride whiskers are [Mg - (OH) 4]2 -and [Mg - Cl 4]2 -. The growth process is the incorporation process of growth units. Growth units will have different incorporations and orientations caused by different system characters or heating. Furthermore, the formation mechanism of basic magnesium chloride whiskers was also interpreted using anion coordination polyhedron growth units.
基金the National Natural Science Foundation of China(22090043 and 21622101)Guangxi Natural Science Foundation(2019GXNSFGA245006)for financial support+2 种基金the National Natural Science Foundation of China(21527803 and 21621061)the Ministry of Science and Technology of China(2016YFA0301004)for financial supportthe funding from China Postdoctoral Science Foundation(8206300392)。
文摘Lowering the operating temperature of solid oxide fuel cells(SOFCs)has extensively stimulated the development of new oxide ion conductors.Here,inspired by the structural commonalities of oxide ion conductors,the inability to accommodate oxygen vacancies in the rigid,isolated,3-fold tetrahedral rings of SrSi/GeO_(3)-based materials,and the considerable flexibility of BO_(n) polyhedra in terms of coordination number,rotation,deformation,and linkage,we report the first borate-base family of oxide ion conductors,(Gd/Y)_(1−x)Zn_(x)BO_(3−0.5x),through combined computational prediction and experimental verification.The oxygen vacancies in(Gd/Y)BO_(3)can be accommodated by forming B_(3)O_(8)units in isolated,3-fold,tetrahedral rings of B_(3)O_(9)and transported through a cooperative mechanism of oxygen exchange between the B_(3)O_(9)and B_(3)O_(8)units,which is assisted by the intermediate opening and extending of these units.This study opens a new scientific field of the borate system for designing and discovering oxide ion conductors.
基金Project supported by the National Natural Science Foundation of China(No.81301343)
文摘Objective: To investigate stretch-induced electrophysiological changes in chronically infarcted hearts and the effect of streptomycin (SM) on these changes in vivo. Methods: Sixty Wistar rats were divided randomly into four groups: a control group (n=15), an SM group (n=15), a myocardial infarction (MI) group (n=15), and an MI+SM group (n=15). Chronic MI was obtained by ligating the left anterior descending branch (LAD) of rat hearts for eight weeks. The in vivo blockade of stretch-activated ion channels (SACs) was achieved by intramuscular injection of SM (180 mg/(kg·d)) for seven days after operation. The hearts were stretched for 5 s by occlusion of the aortic arch. Suction electrodes were placed on the anterior wall of left ventricle to record the monophasic action potential (MAP). The effect of stretching was examined by assessing the 90% monophasic action potential duration (MAPD90), premature ventricular beats (PVBs), and ventricular tachycardia (VT). Results: The MAPD90 decreased during stretching in both the control (from (50.27±5.61) ms to (46.27±4.51) ms, P〈0.05) and MI groups (from (65.47±6.38) ms to (57.47±5.76 ms), P〈0.01 ). SM inhibited the decrease in MAPD90 during inflation ((46.27±4.51) ms vs. (49.53±3.52) ms, P〈0.05 in normal hearts; (57.47±5.76) ms vs. (61.87±5.33) ms, P〈0.05 in MI hearts). The occurrence of PVBs and VT in the MI group increased compared with that in the control group (PVB: 7.93±1.66 vs. 1.80±0.86, P〈0.01; VT: 7 vs. 1, P〈0.05). SM decreased the occurrence of PVBs in both normal and MI hearts (0.93±0.59 vs. 1.80±0.86 in normal hearts, P〈0.05; 5.40±1.18 vs. 7.93±1.66 in MI hearts, P〈0.01). Conclusions: Stretch-induced MAPD90 changes and arrhythmias were observed in chronically infarcted myocardium. The use of SM in vivo decreased the incidence of PVBs but not of VT. This suggests that SACs may be involved in mechanoelectric feedback (MEF), but that there might be other mechanisms involved in causing VT in chronic MI.