The dynamic characteristics of three-tower and two-span suspension bridge are analyzed at different global temperatures. An equivalent cable inner force method is proposed to consider temperature effects and to study ...The dynamic characteristics of three-tower and two-span suspension bridge are analyzed at different global temperatures. An equivalent cable inner force method is proposed to consider temperature effects and to study the effects of environmental temperature on dynamic characteristics of Taizhou Yangtze River Bridge. The result demonstrates that the effects of temperature can not be neglected in static or dynamic analysis of Taizhou Yangtze River Bridge. The relationship between temperature and frequency is negative. The effects of temperature should be taken into account in experimental modal analysis of long-span bridges and damage identification.展开更多
Background Whilst the majority of the patients with severe aortic stenosis can be directly addressed to surgical aortic valve replace- ment (AVR) or transcatheter aortic valve implantation (TAVI), in some instance...Background Whilst the majority of the patients with severe aortic stenosis can be directly addressed to surgical aortic valve replace- ment (AVR) or transcatheter aortic valve implantation (TAVI), in some instances additional information may be needed to complete the diagnostic workout. We evaluated the role of balloon aortic valvuloplasty (BAV) as a bridge-to-decision (BTD) in selected high-risk patients. Methods Between 2007 and 2012, the heart team in our Institution required BTD BAV in 202 patients. Very low left ventricular ejection fraction, mitral regurgitation grade 〉 3, frailty, hemodynamic instability, serious comorbidity, or a combination of these factors were the main drivers for this strategy. We evaluated how BAV influenced the final treatment strategy in the whole patient group and in each specific subgroup. Results Mean logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE) was 23.5%±15.3%, age 81 ± 7 years. In-hospital mortality was 4.5%, cerebrovascular accident 1% and overall vascular complications 4% (0.5% major; 3.5% minor). Of the 193 patients with BTD BAV who survived and received a second heart team evaluation, 72.6% were finally deemed eligible for definitive treatment (25.4% for AVR; 47.2% for TAVI): 96.7% of patients with left ventricular ejection fraction recovery; 70.5% of patients with mitral regurgitation reduction; 75.7% of patients who underwent BAV in clinical hemodynamic instability; 69.2% of frail patients and 68% of patients who presented serious comorbidities. Conclusions Balloon aortic valvuloplasty can be considered as bridge-to- decision in high-risk patients with severe aortic stenosis who cannot be immediate candidates for definitive transcatheter or surgical treatment.展开更多
Over the recent three decades, exploration of a large-size Sn-Fe polymetallic ore deposit at the Huanggangliang, the Da Hinggan Mountains, Inner Mongolia, China, has been largely focused on the premise that the minera...Over the recent three decades, exploration of a large-size Sn-Fe polymetallic ore deposit at the Huanggangliang, the Da Hinggan Mountains, Inner Mongolia, China, has been largely focused on the premise that the mineralization represents epigenetic magmatic hydrothermal ore deposit in genetic connection with the Mesozoic magmatism. The Huanggangliang Sn-Fe polymetallic ore deposits occurred in Permian strata, with silt- stone/marble of the Zhesi Formation and spilite/andesite/tuff of the Dashizhai Formation. The characteristics of geological and geochemical data demonstrated that sedimentary hydrothermal mineralization occurred during the basin evolution at the Permian, rather than representing epigenetie magmatic hydrothermal genesis with the following evidences. The ore-bearing skarus are stratiform with underlying metasedimentary rocks and overlying volcanic sedimentary rocks. Sedimentary hydrothermal textures and structures are observed in the stratabound ore-bearing skarn such as bedded-laminated skarn and magnetite ores with small-size folding or soft deforma- tion, synsedimentary breccia of skarn and magnetite ores and concentric shell structure of magnetite ores. So the stratabound ore-bearing skarns associated with magnetite ore and micro-disseminated tin, are peculiar examples of exhalite. The REE contents of the stratabound ore-bearing skarns display ∑LREE-rich (36.91×10^-6) but EHREE-depletion (6. 42 ×10^-6) , with positive Eu anomaly (Eu/Eu * 1.28) and negative Ce anomaly (Ce/ Ce * 0.88 ) , which is totally different from REE pattern of the Huanggang magmatic rocks( with ∑REE 277.73 ×10^-6, ELREE 220.24 ×10^-6, ∑HREE 57.49 ×10^-6, Eu/Eu* 0.06, Ce/Ce* 1.52) , which is comparable with modern sea-floor hydrothermal fluid,sedimentary hydrothermal ore deposit and associated hydrothermal sedimentary rocks. Calcite samples with δ13CPDB from -5. 400 ‰ to -4. 397 ‰ and δ18SOSMOW from 9. 095 ‰ to 9. 364 ‰ in the stratabound ore-bearing skarns show sedimentary hydrothermal genesis of the Huanggangliang deposit. This proposition is useful not only for interpretation of the genesis of the Huanggangliang large Sn-Fe polymetallic ore deposit but also significant for mineral exploration in the area especially for finding large deposits caused by sedimentary exhalative mineralization processes.展开更多
The peculiarities of calculating isolated structures with spherical bearings are analyzed in this paper. Some of peculiarities are caused by the lack of data at the moment when engineering solutions had to be made, Ot...The peculiarities of calculating isolated structures with spherical bearings are analyzed in this paper. Some of peculiarities are caused by the lack of data at the moment when engineering solutions had to be made, Other peculiarities are connected with physical peculiarities of the device behaviour. To provide the analysis of structure hehaviour under the condition of the lack of input information, two types of design models of seismic protection devices were considered. They are the dampers linearization and the modelling of real dampers by dry friction ones. The dampers linearization makes it possible to use the existing software for calculating linear strongly-damped systems. To calculate structures with dry friction dampers, a new software was worked out. In this case, the structure is described as a piecewise-linear system of a relay-type. The investigations of the structure oscillations take into account both horizontal and vertical components of earthquake input. Under this condition, horizontal oscillation equations of structures are the MaRie-Hill ones. The input and structure parameters which caused the structure instability are estimated. To exclude the structure instability, high damping devices should be used. These methods were used for seismic resistant analysis of bridges with spherical bearings and hydraulic dampers applied in Sochi.展开更多
A real-time,long-round global positioning system (GPS) bridge-deformation monitoring technology was proposed,which processes the carrier phase of multiple GPS receivers in an operation center.It was demon- strated an ...A real-time,long-round global positioning system (GPS) bridge-deformation monitoring technology was proposed,which processes the carrier phase of multiple GPS receivers in an operation center.It was demon- strated an extended Kalman filter with triple differential ionospheric-free measurement (EKF-TIF) which can eliminate the ionospheric delay,whiten the TIF noise and optimize the results of EKF,consequently,achieves a better performance than existing real time kinematic (RTK) solution.An experiment,which takes an active ionosphere condition into consideration,proves the feasibility of this system by comparing its records to that of a traditional RTK solution,practically,the system installed on the Donghai Bridge has survived a non-break running for five months.The analysis to the monitoring records shows the system achieves the designed accu- racy and reliability.展开更多
Construction progress of long-span bridge is complicated and the quality control is strict. Any disadvantage during construction may potentially affect the internal forces and deck alignments after it is open to traff...Construction progress of long-span bridge is complicated and the quality control is strict. Any disadvantage during construction may potentially affect the internal forces and deck alignments after it is open to traffic. To exactly evaluate the periodic alignments, internal forces and safety, geometrical and physical monitoring are needed during construction. This study aims at the requirement of dynamic geometric monitoring during Sutong Bridge construction, and introduces the realization and observing schemes of the self-developed GPS real-time dynamic geometrical deformation monitoring system. Affected by wind load and construction circumstance, GPS (global positioning system) monitoring signal contains a variety of noise. And the useful signal can be extracted from the signal after de-noising the noises. A de-noising method based on EMD (empirical mode decomposition) model is introduced here to process the bridge dynamic monitoring data, and with the wavelet threshold de-noising method are compared. The result shows that the EMD method has good adaptability, is free from the choice of wavelet bases and the number of decomposition layer. The method is an effective de-noising method for dynamic deformation monitoring to large-span bridges.展开更多
A theoretical model of focused acoustic field for a multi-annular phased array on concave spherical surface is proposed. In this model, the source boundary conditions of the spheroidal beam equation (SBE) for multi-...A theoretical model of focused acoustic field for a multi-annular phased array on concave spherical surface is proposed. In this model, the source boundary conditions of the spheroidal beam equation (SBE) for multi-annular phased elements are studied. Acoustic field calculated by the dynamic focusing model of SBE is compared with numerical results of the O'Neil and Khokhlov-Zabolotskaya-Kuznetsov (KZK) model, respectively. Axia/dynamic focusing and the harmonic effects are presented. The results demonstrate that the dynamic focusing model of SBE is good valid for a concave multi-annular phased array with a large aperture angle in the linear or nonlinear field.展开更多
Using the vector diffraction theory and the phenomenological model, this paper investigates the second harmonic tion (SHG) of a single centrosymmetric nanosphere excited by focused doughnut beams (DBs) with differ...Using the vector diffraction theory and the phenomenological model, this paper investigates the second harmonic tion (SHG) of a single centrosymmetric nanosphere excited by focused doughnut beams (DBs) with different topological charges. The results show that strong backward SHG (BSHG) appears when the particle is excited by focused DBs with topological charges of ±1. The backward second harmonic radiation can be caused by the depolarized effect of high numerical aperture (NA) objectives due to the strong longitudinal components.展开更多
基金National Science and Technology Support Program of China ( No. 2009BAG15B03)National Sci-ence Foundation Support Project( No. 51078080)
文摘The dynamic characteristics of three-tower and two-span suspension bridge are analyzed at different global temperatures. An equivalent cable inner force method is proposed to consider temperature effects and to study the effects of environmental temperature on dynamic characteristics of Taizhou Yangtze River Bridge. The result demonstrates that the effects of temperature can not be neglected in static or dynamic analysis of Taizhou Yangtze River Bridge. The relationship between temperature and frequency is negative. The effects of temperature should be taken into account in experimental modal analysis of long-span bridges and damage identification.
文摘Background Whilst the majority of the patients with severe aortic stenosis can be directly addressed to surgical aortic valve replace- ment (AVR) or transcatheter aortic valve implantation (TAVI), in some instances additional information may be needed to complete the diagnostic workout. We evaluated the role of balloon aortic valvuloplasty (BAV) as a bridge-to-decision (BTD) in selected high-risk patients. Methods Between 2007 and 2012, the heart team in our Institution required BTD BAV in 202 patients. Very low left ventricular ejection fraction, mitral regurgitation grade 〉 3, frailty, hemodynamic instability, serious comorbidity, or a combination of these factors were the main drivers for this strategy. We evaluated how BAV influenced the final treatment strategy in the whole patient group and in each specific subgroup. Results Mean logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE) was 23.5%±15.3%, age 81 ± 7 years. In-hospital mortality was 4.5%, cerebrovascular accident 1% and overall vascular complications 4% (0.5% major; 3.5% minor). Of the 193 patients with BTD BAV who survived and received a second heart team evaluation, 72.6% were finally deemed eligible for definitive treatment (25.4% for AVR; 47.2% for TAVI): 96.7% of patients with left ventricular ejection fraction recovery; 70.5% of patients with mitral regurgitation reduction; 75.7% of patients who underwent BAV in clinical hemodynamic instability; 69.2% of frail patients and 68% of patients who presented serious comorbidities. Conclusions Balloon aortic valvuloplasty can be considered as bridge-to- decision in high-risk patients with severe aortic stenosis who cannot be immediate candidates for definitive transcatheter or surgical treatment.
基金Project supported by the National Basic Research Program(2009CB421008)Program for Changjiang Scholars and Innovative Research Teamin University (IRT0755)+1 种基金the 111 Project (B07011)China Postdoctoral Science Foundation funded project (20090460400)
文摘Over the recent three decades, exploration of a large-size Sn-Fe polymetallic ore deposit at the Huanggangliang, the Da Hinggan Mountains, Inner Mongolia, China, has been largely focused on the premise that the mineralization represents epigenetic magmatic hydrothermal ore deposit in genetic connection with the Mesozoic magmatism. The Huanggangliang Sn-Fe polymetallic ore deposits occurred in Permian strata, with silt- stone/marble of the Zhesi Formation and spilite/andesite/tuff of the Dashizhai Formation. The characteristics of geological and geochemical data demonstrated that sedimentary hydrothermal mineralization occurred during the basin evolution at the Permian, rather than representing epigenetie magmatic hydrothermal genesis with the following evidences. The ore-bearing skarus are stratiform with underlying metasedimentary rocks and overlying volcanic sedimentary rocks. Sedimentary hydrothermal textures and structures are observed in the stratabound ore-bearing skarn such as bedded-laminated skarn and magnetite ores with small-size folding or soft deforma- tion, synsedimentary breccia of skarn and magnetite ores and concentric shell structure of magnetite ores. So the stratabound ore-bearing skarns associated with magnetite ore and micro-disseminated tin, are peculiar examples of exhalite. The REE contents of the stratabound ore-bearing skarns display ∑LREE-rich (36.91×10^-6) but EHREE-depletion (6. 42 ×10^-6) , with positive Eu anomaly (Eu/Eu * 1.28) and negative Ce anomaly (Ce/ Ce * 0.88 ) , which is totally different from REE pattern of the Huanggang magmatic rocks( with ∑REE 277.73 ×10^-6, ELREE 220.24 ×10^-6, ∑HREE 57.49 ×10^-6, Eu/Eu* 0.06, Ce/Ce* 1.52) , which is comparable with modern sea-floor hydrothermal fluid,sedimentary hydrothermal ore deposit and associated hydrothermal sedimentary rocks. Calcite samples with δ13CPDB from -5. 400 ‰ to -4. 397 ‰ and δ18SOSMOW from 9. 095 ‰ to 9. 364 ‰ in the stratabound ore-bearing skarns show sedimentary hydrothermal genesis of the Huanggangliang deposit. This proposition is useful not only for interpretation of the genesis of the Huanggangliang large Sn-Fe polymetallic ore deposit but also significant for mineral exploration in the area especially for finding large deposits caused by sedimentary exhalative mineralization processes.
文摘The peculiarities of calculating isolated structures with spherical bearings are analyzed in this paper. Some of peculiarities are caused by the lack of data at the moment when engineering solutions had to be made, Other peculiarities are connected with physical peculiarities of the device behaviour. To provide the analysis of structure hehaviour under the condition of the lack of input information, two types of design models of seismic protection devices were considered. They are the dampers linearization and the modelling of real dampers by dry friction ones. The dampers linearization makes it possible to use the existing software for calculating linear strongly-damped systems. To calculate structures with dry friction dampers, a new software was worked out. In this case, the structure is described as a piecewise-linear system of a relay-type. The investigations of the structure oscillations take into account both horizontal and vertical components of earthquake input. Under this condition, horizontal oscillation equations of structures are the MaRie-Hill ones. The input and structure parameters which caused the structure instability are estimated. To exclude the structure instability, high damping devices should be used. These methods were used for seismic resistant analysis of bridges with spherical bearings and hydraulic dampers applied in Sochi.
文摘A real-time,long-round global positioning system (GPS) bridge-deformation monitoring technology was proposed,which processes the carrier phase of multiple GPS receivers in an operation center.It was demon- strated an extended Kalman filter with triple differential ionospheric-free measurement (EKF-TIF) which can eliminate the ionospheric delay,whiten the TIF noise and optimize the results of EKF,consequently,achieves a better performance than existing real time kinematic (RTK) solution.An experiment,which takes an active ionosphere condition into consideration,proves the feasibility of this system by comparing its records to that of a traditional RTK solution,practically,the system installed on the Donghai Bridge has survived a non-break running for five months.The analysis to the monitoring records shows the system achieves the designed accu- racy and reliability.
文摘Construction progress of long-span bridge is complicated and the quality control is strict. Any disadvantage during construction may potentially affect the internal forces and deck alignments after it is open to traffic. To exactly evaluate the periodic alignments, internal forces and safety, geometrical and physical monitoring are needed during construction. This study aims at the requirement of dynamic geometric monitoring during Sutong Bridge construction, and introduces the realization and observing schemes of the self-developed GPS real-time dynamic geometrical deformation monitoring system. Affected by wind load and construction circumstance, GPS (global positioning system) monitoring signal contains a variety of noise. And the useful signal can be extracted from the signal after de-noising the noises. A de-noising method based on EMD (empirical mode decomposition) model is introduced here to process the bridge dynamic monitoring data, and with the wavelet threshold de-noising method are compared. The result shows that the EMD method has good adaptability, is free from the choice of wavelet bases and the number of decomposition layer. The method is an effective de-noising method for dynamic deformation monitoring to large-span bridges.
基金Supported by the National Natural Science Foundation of China under Grant Nos. 39970209 and 30772072
文摘A theoretical model of focused acoustic field for a multi-annular phased array on concave spherical surface is proposed. In this model, the source boundary conditions of the spheroidal beam equation (SBE) for multi-annular phased elements are studied. Acoustic field calculated by the dynamic focusing model of SBE is compared with numerical results of the O'Neil and Khokhlov-Zabolotskaya-Kuznetsov (KZK) model, respectively. Axia/dynamic focusing and the harmonic effects are presented. The results demonstrate that the dynamic focusing model of SBE is good valid for a concave multi-annular phased array with a large aperture angle in the linear or nonlinear field.
基金supported by the National High Technology Research and Development Program of China (No.2011AA010205)the National Natural Science Foundation of China (Nos.10704043 and 61171027)+1 种基金the Key Program of the Applied Basic Research of Tianjin (No.10JCZDJC15200)the Specialized Research Fund for the Doctoral Program of Higher Education of China (No.20090031110033)
文摘Using the vector diffraction theory and the phenomenological model, this paper investigates the second harmonic tion (SHG) of a single centrosymmetric nanosphere excited by focused doughnut beams (DBs) with different topological charges. The results show that strong backward SHG (BSHG) appears when the particle is excited by focused DBs with topological charges of ±1. The backward second harmonic radiation can be caused by the depolarized effect of high numerical aperture (NA) objectives due to the strong longitudinal components.