A kind of construction truck model is built in Adams based on multi-body dynamic theory. The rigid and elastic wheels of tire-soil contact models are proposed based on the Bekker pressure model and the Jonasi shear so...A kind of construction truck model is built in Adams based on multi-body dynamic theory. The rigid and elastic wheels of tire-soil contact models are proposed based on the Bekker pressure model and the Jonasi shear soil model, and they are described in the form of S-function to enhance the calculation efficiency and simulation accuracy. Finally, the interaction of truck and soil is simulated by Adams-Maflab co-simulation to study the influence of soft terrain on the ride comfort of vehicles. The co-simulation results reveal that the terrain properties have a great influence on the ride comfort of vehicles as well as driving speed, road roughness and cargo weight. This co-simulation model is convenient for adding the factor of terrain deformation to the analysis of vehicle ride comfort. It can also be used to optimize suspension system parameters especially for off-road vehicles.展开更多
Aim To develop an HPLC method with fluorescence detection for the assay ofDL111-IT in rabbit plasma. Methods DL111-IT and internal standard glybenzcyclamide in rabbit plasmawere extracted with chloroform. The determin...Aim To develop an HPLC method with fluorescence detection for the assay ofDL111-IT in rabbit plasma. Methods DL111-IT and internal standard glybenzcyclamide in rabbit plasmawere extracted with chloroform. The determination was performed on a Diamonsil ODS-C_(18) column(150 mm x 4.6 mm, 5 μm) with a mobile phase of acetonitrile and 0.025 mol·L^(-1) diammoniumhydrogen phosphate buffer (pH 5.0, adjusted by phosphoric acid) (60:40, V/V) at a flow-rate of 1.0mL·min^(-1) . Fluorescence detector was operated at excitation wavelength of 250 nm and emissionwavelength of 332 nm. Results The calibration curve in plasma was linear from 1.00 - 20.00ng·mL^(-1) ( r = 0.999 6, n = 5). The method afforded average extracting recoveries of 85.3% ±1.3%, 84.9% ± 2.7% and 85.8% ± 1.8%, and the average method recoveries were 99.5% ±0.4%, 102.1%± 1.8% and 101.3% ± 2.4% for the high (20.00 ng·mL^(-1)) , middle (10.00 ng·mL^(-1)) and low (1.00 ng·mL^(-1)) check samples, respectively. The intra-day (n = 5) and inter-day (n = 5) precisions(RSD) were less than 3.0% and 7.0%, respectively. The limit of detection and quantitation for themethod were 0.3 ng·mL^(-1) (S/N = 3) and 1 ng·mL^(-1) (S/N = 10, RSD<7.0%) plasma sample,respectively. Conclusion The developed method was accurate, sensitive, simple and could be used forpharmacokinetic study of DL111- IT.展开更多
To improve magnetotelluric(MT)nonlinear inversion accuracy and stability,this work introduces the deep belief network(DBN)algorithm.Firstly,a network frame is set up for training in different 2D MT models.The network ...To improve magnetotelluric(MT)nonlinear inversion accuracy and stability,this work introduces the deep belief network(DBN)algorithm.Firstly,a network frame is set up for training in different 2D MT models.The network inputs are the apparent resistivities of known models,and the outputs are the model parameters.The optimal network structure is achieved by determining the numbers of hidden layers and network nodes.Secondly,the learning process of the DBN is implemented to obtain the optimal solution of network connection weights for known geoelectric models.Finally,the trained DBN is verified through inversion tests,in which the network inputs are the apparent resistivities of unknown models,and the outputs are the corresponding model parameters.The experiment results show that the DBN can make full use of the global searching capability of the restricted Boltzmann machine(RBM)unsupervised learning and the local optimization of the back propagation(BP)neural network supervised learning.Comparing to the traditional neural network inversion,the calculation accuracy and stability of the DBN for MT data inversion are improved significantly.And the tests on synthetic data reveal that this method can be applied to MT data inversion and achieve good results compared with the least-square regularization inversion.展开更多
In recent several years,some works have been done on cosmic thermodynamics.The apparent horizonwas regarded as the key characteristic supersurface where thermodynamics can be built on perfectly.However,if theirreversi...In recent several years,some works have been done on cosmic thermodynamics.The apparent horizonwas regarded as the key characteristic supersurface where thermodynamics can be built on perfectly.However,if theirreversible process is considered,the proper position for building thermodynamics will not be the apparent horizonanymore.The new position is related to dark energy state equation and the irreversible process parameters.展开更多
This paper presents a weakly nonlinear water wave model using a mild slope equation and a new explicit formulation which takes into account dispersion of wave phase velocity, approximates Hedges’ (1987) nonlinear dis...This paper presents a weakly nonlinear water wave model using a mild slope equation and a new explicit formulation which takes into account dispersion of wave phase velocity, approximates Hedges’ (1987) nonlinear dispersion relationship, and accords well with the original empirical formula. Comparison of the calculating results with those obtained from the experimental data and those obtained from linear wave theory showed that the present water wave model considering the dispersion of phase velocity is rational and in good agreement with experiment data.展开更多
Diesel Particulate Matter (DPM) is regulated in the U.S. for both underground coal and metal/nonmetal mines. Today, many underground mines still face difficulty in compliance with DPM regulations. The DPM research c...Diesel Particulate Matter (DPM) is regulated in the U.S. for both underground coal and metal/nonmetal mines. Today, many underground mines still face difficulty in compliance with DPM regulations. The DPM research carried out in Missouri University of Science and Technology (MST) is to use computational fluid dynamics (CFD) to study the DPM distribution in commonly used face areas. The result is expected to be used for selection of DPM reduction strategies and better working practices, which can help the underground mines to meet regulation limits and improve the working environment for the miners. An experiment was conducted at MST's Experimental Mine to validate CFD simulation. DPM was collected at four locations downstream of a stationary diesel engine. The experiment data were then compared with the CFD simulation results. The comparison shows that CFD simulation can forecast the location of DPM concentration with practical accuracy (less than 0.15 m). CFD can be used to further study DPM distribution in commonly used working faces and give guidance to DPM reduction.展开更多
Geologists can offer key insights in regard to several high profile environmental issues that are faced today. At the same time, like scientists in most other disciplines, many geologists are not naturally adept at co...Geologists can offer key insights in regard to several high profile environmental issues that are faced today. At the same time, like scientists in most other disciplines, many geologists are not naturally adept at communicating in an effective manner with non-geologists. This paper firstly identifies the more subtle facets of topical major issues (the drivers) where geologists can contribute important perspectives. Next, the detractions to effective communication are identified, along with the recommended means to overcome them (the mechanisms). Many topical issues are in fact geologically-underpinned (e.g. obviously, geohazards), so geologists ought to have something meaningful to say. By the same token, if geologists have difficulty communicating with other scientists, how can they possibly hope to communicate with journalists and with the public at large? Proper scientific contextualization is an ideal starting point, but this fundamental framing step does not always suit protagonists who have non-scientific agendas. Thus, geologists not only have to convey their science (geology) in an understandable way, but to do so in a truly effective manner must recognize and take into account possible predispositions that their audience may have.展开更多
The non-coupled charge explosion and geo-mechanical dynamics problem in real air condition is studied in this paper. It analyzes and calculates the problem by using the real air state equations. Through researching on...The non-coupled charge explosion and geo-mechanical dynamics problem in real air condition is studied in this paper. It analyzes and calculates the problem by using the real air state equations. Through researching on the non-coupled charge rock bench blasting with big clearance of air, its result indicates that the borehole wall reflection overpressure is far higher than strength of rock, but much lower than detonation front pressure of the charge. So non-coupled charge explosion blasting engineering is very successful. Furthermore, it introduces the method of shaft forming by blasting once and the new tube room technology. And the non-coupled charge explosion is used successfully in the method of shaft forming by blasting once. As it drills and blasts in the top and removes the broken rock from the bottom tunnel, it increases the construction efficiency significantly. This paper has important reference on the improvement of the large-span underground engineering construction.展开更多
Elimination of human losses is the main and immediate task in the seismic vulnerability problem.The authors suggest the ways of development of seismic research and discussion of defense problems for reducing of seismi...Elimination of human losses is the main and immediate task in the seismic vulnerability problem.The authors suggest the ways of development of seismic research and discussion of defense problems for reducing of seismic vulnerability. It is the ways of nonlinear seismology region. Unconditionally seism zoning and the theory of catastrophes allow reduce human losses and building destruction. But well-known isoseists are the private case of caustic catastrophe theory or seismo-acoustics, so seism zoning can be amounted to 6 elementary catastrophe forms. It will better help to predict seismic actions. The short-time local prediction of seismic events is general method for strong reducing of human losses. This method takes into account chaotic properties of stress fields and waves and the peculiarities of urban area. It bases on the natural seismo-emission phenomenon and is realized by long-time monitoring, which gives statistically and geographically continuous picture (chart) of seismic noise level inside geologic media. The instruments of this strategy are shock and pressure-proofed seismometers for long-time monitoring and control the state of geological media including underwater shelf areas. The authors think that the active protecting for cities and buildings as the best modem form of people safety consists in stress discharge of geologic media. Ultrasonic wave defense includes and bases on strong interaction between powerful waves from earthquake and ultrasonic wave train. The authors want to point out that the technical objects may be used lbr the investigation of earthquakes induced and some reasons of seismic vulnerability. Also reducing of seismic vulnerability contains as component kinetic acting on volcano at the pre-explosive stage. The interesting and important aspect of defense problem is observation of the inharmonic wave processes in the soil and quasi-constant forces as the nearest seismic analogue of radiation forces in nonlinear acoustics under powerful earthquake seismic tremor.展开更多
During underground coal gasification (UCG), whereby coal is converted to syngas in situ, a cavity is formed in the coal seam. The cavity growth rate (CGR) or the moving rate of the gasification face is affected by...During underground coal gasification (UCG), whereby coal is converted to syngas in situ, a cavity is formed in the coal seam. The cavity growth rate (CGR) or the moving rate of the gasification face is affected by controllable (operation pressure, gasification time, geometry of UCG panel) and uncontrollable (coal seam properties) factors. The CGR is usually predicted by mathematical models and laboratory experiments, which are time consuming, cumbersome and expensive. In this paper, a new simple model for CGR is developed using non-linear regression analysis, based on data from 1 l UCG field trials. The empirical model compares satisfactorily with Perkins model and can reliably predict CGR.展开更多
Combining the field monitoring results of a deep-buried tunnel in Chongqing,the dynamic characteristics of the surrounding rock system under high in situ stress wasanalyzed by phase space reconstruction, calculating c...Combining the field monitoring results of a deep-buried tunnel in Chongqing,the dynamic characteristics of the surrounding rock system under high in situ stress wasanalyzed by phase space reconstruction, calculating correlation dimension, Kolmogoroventropy and largest Lyapunov exponents.Both the Kolmogorov entropy and largestLyapunov exponents show that the surrounding rock system is a chaotic one.Based onthis, a local model was applied to predict surrounding rock displacement, and a nonlineardynamic model was derived to forecast the interaction of the surrounding rock and supportstructure.The local method was found to have an extremely small total error.Also, thenonlinear dynamic model forecasting curves agree with the monitoring ones very well.It isproved that the nonlinear dynamic characteristic study is very important in analyzing rockstability and predicting the evolution of rock systems.展开更多
Ground motions are significantly influenced by dynamic characteristics of overburden soil layers near ground surface,as thick and soft soil layers would obviously amplify the ground motion strength. The conventional r...Ground motions are significantly influenced by dynamic characteristics of overburden soil layers near ground surface,as thick and soft soil layers would obviously amplify the ground motion strength. The conventional research method on soil nonlinear dynamic characteristics under strong motions is based on experiments in laboratories for the deficiency of observation data,but it is difficult to reliably simulate the complex factors of soils in actual earthquake durations,including loading paths,boundary conditions,and drainage conditions. The incremental data of the vertical downhole observation array,which is comprised of at least one observation point on ground surface and one observation point in a downhole rock base, makes it possible to study soil nonlinear dynamics according to in situ observation data,and provides new basic data and development opportunities to soil nonlinear dynamics studies.展开更多
Over the last 30 years, environmental philosophers and ecological researchers have turned their attention to the possibilities of narratives: the stories people tell about their lives in conjunction with the human an...Over the last 30 years, environmental philosophers and ecological researchers have turned their attention to the possibilities of narratives: the stories people tell about their lives in conjunction with the human and non-human agents they live with. An interest in narrative environmental ethics reflects a re-evaluation of canonical ecophilosophical texts. Works such as Paul W. Taylor's Respect for Nature suggest an essentialist view of environmental ethics in which predetermined principles are imposed on places and situations. On the other hand, Aldo Leopold's A Sand County Almanac combines first-person prose with science-based explanations of the "biotic pyramid" towards the development of a land ethic. Examples, such as Leopold's, of narrative ethics are thought to offer relational, place-based, non-authoritative, and non-anthropocentric models. This article examines three critical components of environmental narratives: self, context, and tradition. In order for environmental narratives to advance ecological ethics, they must be accompanied by the tradition of natural science (geology, ecology, and evolution) to provide the "sponsoring ground" for ethical concern and action. The role of natural science as a tradition--and indeed one of many--in narrative ethics provides the basis for ecological selfhood in the context of place. These assertions will be supported by an analysis of the environmental narratives of Karen Warren and Jim Cheney. However, in the temporally expansive and ecologically conscious poetic narratives of John Kinsella we find an environmental ethics deeply rooted in the material realities of place.展开更多
Let A and B be two factor von Neumann algebras. For A, B ∈ A, define by [A, B]_*= AB-BA~*the skew Lie product of A and B. In this article, it is proved that a bijective map Φ : A → B satisfies Φ([[A, B]_*, C]_*) =...Let A and B be two factor von Neumann algebras. For A, B ∈ A, define by [A, B]_*= AB-BA~*the skew Lie product of A and B. In this article, it is proved that a bijective map Φ : A → B satisfies Φ([[A, B]_*, C]_*) = [[Φ(A), Φ(B)]_*, Φ(C)]_*for all A, B, C ∈ A if and only if Φ is a linear *-isomorphism, or a conjugate linear *-isomorphism, or the negative of a linear *-isomorphism, or the negative of a conjugate linear *-isomorphism.展开更多
In situ stress state becomes more and more significant with in-depth research on geodynamics and energy development.However,there has not been an economic and effective method developed to determine deep three-dimensi...In situ stress state becomes more and more significant with in-depth research on geodynamics and energy development.However,there has not been an economic and effective method developed to determine deep three-dimensional in situ stress.The Anelastic Strain Recovery(ASR)method is a newly developed technique that can determine three-dimensional in situ stresses.After the 12 May 2008 Ms8.0 Wenchuan earthquake,the ASR method was used for the first time in China's Mainland to measure the in situ stresses in the WFSD scientific boreholes in Sichuan Province,China.In this paper,the basic procedure of the ASR method is introduced in detail and the compliances of ASR for boring cores are investigated.The results show that the maximum principal stress direction was NW64°at a measured depth(MD)of 1173 m(vertical depth 1151 m)in WFSD-1.The ratio of shear mode to the volume mode compliance of ASR was 2.9.And the three principal stresses at 1173 m MD in WFSD-1are 43,28 and 25 MPa.Combined with stress measurement results determined using other in situ measurement methods along the Longmenshan fault zone,the directions of the maximum horizontal principal stress changes from E-W to NEE-SWW to NWW-SEE when moving from NE to SW along the Longmenshan fault zone.This change is in agreement with the stress regime of the Longmenshan fault zone of the Wenchuan Earthquake,which supports a stress regime consisting predominantly of thrusts in the southwest and strike-slip in the northeast.展开更多
A nonlinear mathematical model is proposed and analyzed to study the dynamics of 2009 HIN1 flu epidemic in a homogeneous population with constant immigration of susceptibles. The effect of contact tracing and quaranti...A nonlinear mathematical model is proposed and analyzed to study the dynamics of 2009 HIN1 flu epidemic in a homogeneous population with constant immigration of susceptibles. The effect of contact tracing and quarantine (isolation) strategies in reduc- ing the spread of H1N1 flu is incorporated. The model monitors the dynamics of five sub-populations (classes), namely susceptible with high infection risk, susceptible with reduction of infection risk, infective, quarantined and recovered individuals. The model analysis includes the determination of equilibrium points and carrying out their stability analysis in terms of the threshold parameter R0. Moreover, the numerical simulation of the proposed model is also performed by using fourth order Runge-Kutta method along with the sensitivity analysis of the endemic equilibrium point. The analysis and numeri- cal simulation results demonstrate that the maximum implementation of contact tracing and quarantine strategies help in reducing endemic infective class size and hence act as effective intervention strategy to control the disease. This gives a theoretical interpreta- tion to the practical experiences that the early contact tracing and quarantine strategies are criticMly important to control the outbreak of epidemics.展开更多
East Africa is a biodiversity hotspot. Haplocarpha rueppelii (Sch.Bip.) Beauverd is mainly distributed in the alpine grassland of East Africa. Here we sampled 65 individuals of eight populations/locations of H. ruep...East Africa is a biodiversity hotspot. Haplocarpha rueppelii (Sch.Bip.) Beauverd is mainly distributed in the alpine grassland of East Africa. Here we sampled 65 individuals of eight populations/locations of H. rueppelii including hairy and glabrous forms from Mts. Elgon, Aberdare, Kenya, Kilimanjaro and Bale Mountains. We then sequenced one nuclear and three chloroplast DNA fragments and conducted phylogeographic analyses to test the taxonomic rank of the two forms and causes for the differentiation (intrinsic reproductive isolation and geographic barrier). The results demonstrate that the species consists of two major groups, one includes the populations from Mts. Elgon, Aberdare and Bale, while the other includes Mts. Kenya and Kilimanjaro. The species has established in Mts. Kenya and Aberdare during the Pleistocene. However, migration rate for individuals between the two mountains was low as showed by gene flow analysis. A barrier for plant dispersal and gene flow would have existed between Mts. Aberdare and Kenya since at least Pleistocene. No change of the taxonomic concept of this species is needed. This study reveals a potential geographic barrier in East Africa. We hope it will arouse more scientists' interests in phylogeography and biodiversity of East Africa.展开更多
Target-mediated drug disposition (TMDD)model is one of the main modeling theories for studying nonlinear pharmacokinetics (PK)ofmonoclonal antibodies.However,there are too many parameters in full TMDD model to be esti...Target-mediated drug disposition (TMDD)model is one of the main modeling theories for studying nonlinear pharmacokinetics (PK)ofmonoclonal antibodies.However,there are too many parameters in full TMDD model to be estimated based on limited clinical data,leading to instability of the final model.In the present study,we analyzed the predictive ability and applicability of a simplified quasi-steady state (QSS)model with the assumption that the total target concentration was a constant parameter during treatment with monoelonal antibody in clinical data modeling.Based on the parameters of a published TMDD model of denosumab,simulations were performed at population and individual levels.Then,a simplified TMDD model,QSS model, was used to examine the effects of hypotheses,in which the total receptor concentration was constant or variable on model fit and stability of parameter estimation.Both simulations at the population level and model fit results of simulated individual data showed that at the therapeutic doses,the total receptor concentration had little influence on changes in drug concentration,and the model with constant total receptor concentration had the same predictive power.The validated hypothesis could be applied to clinical trial design and selection of the optimal PK model in the development of monoclonal antibodies.展开更多
基金The National Natural Science Foundation of China(No.50575040)the Natural Science Foundation of Jiangsu Province(No.BK2007112)
文摘A kind of construction truck model is built in Adams based on multi-body dynamic theory. The rigid and elastic wheels of tire-soil contact models are proposed based on the Bekker pressure model and the Jonasi shear soil model, and they are described in the form of S-function to enhance the calculation efficiency and simulation accuracy. Finally, the interaction of truck and soil is simulated by Adams-Maflab co-simulation to study the influence of soft terrain on the ride comfort of vehicles. The co-simulation results reveal that the terrain properties have a great influence on the ride comfort of vehicles as well as driving speed, road roughness and cargo weight. This co-simulation model is convenient for adding the factor of terrain deformation to the analysis of vehicle ride comfort. It can also be used to optimize suspension system parameters especially for off-road vehicles.
文摘Aim To develop an HPLC method with fluorescence detection for the assay ofDL111-IT in rabbit plasma. Methods DL111-IT and internal standard glybenzcyclamide in rabbit plasmawere extracted with chloroform. The determination was performed on a Diamonsil ODS-C_(18) column(150 mm x 4.6 mm, 5 μm) with a mobile phase of acetonitrile and 0.025 mol·L^(-1) diammoniumhydrogen phosphate buffer (pH 5.0, adjusted by phosphoric acid) (60:40, V/V) at a flow-rate of 1.0mL·min^(-1) . Fluorescence detector was operated at excitation wavelength of 250 nm and emissionwavelength of 332 nm. Results The calibration curve in plasma was linear from 1.00 - 20.00ng·mL^(-1) ( r = 0.999 6, n = 5). The method afforded average extracting recoveries of 85.3% ±1.3%, 84.9% ± 2.7% and 85.8% ± 1.8%, and the average method recoveries were 99.5% ±0.4%, 102.1%± 1.8% and 101.3% ± 2.4% for the high (20.00 ng·mL^(-1)) , middle (10.00 ng·mL^(-1)) and low (1.00 ng·mL^(-1)) check samples, respectively. The intra-day (n = 5) and inter-day (n = 5) precisions(RSD) were less than 3.0% and 7.0%, respectively. The limit of detection and quantitation for themethod were 0.3 ng·mL^(-1) (S/N = 3) and 1 ng·mL^(-1) (S/N = 10, RSD<7.0%) plasma sample,respectively. Conclusion The developed method was accurate, sensitive, simple and could be used forpharmacokinetic study of DL111- IT.
基金Project(41304090)supported by the National Natural Science Foundation of ChinaProject(2016YFC0303104)supported by the National Key Research and Development Project of ChinaProject(DY135-S1-1-07)supported by Ocean 13th Five-Year International Marine Resources Survey and Development of China
文摘To improve magnetotelluric(MT)nonlinear inversion accuracy and stability,this work introduces the deep belief network(DBN)algorithm.Firstly,a network frame is set up for training in different 2D MT models.The network inputs are the apparent resistivities of known models,and the outputs are the model parameters.The optimal network structure is achieved by determining the numbers of hidden layers and network nodes.Secondly,the learning process of the DBN is implemented to obtain the optimal solution of network connection weights for known geoelectric models.Finally,the trained DBN is verified through inversion tests,in which the network inputs are the apparent resistivities of unknown models,and the outputs are the corresponding model parameters.The experiment results show that the DBN can make full use of the global searching capability of the restricted Boltzmann machine(RBM)unsupervised learning and the local optimization of the back propagation(BP)neural network supervised learning.Comparing to the traditional neural network inversion,the calculation accuracy and stability of the DBN for MT data inversion are improved significantly.And the tests on synthetic data reveal that this method can be applied to MT data inversion and achieve good results compared with the least-square regularization inversion.
基金Supported by the National Natural Science Foundation of China under Grant Nos.10773002 and 10875012the National Basic Research Program of China under Grant No.2003CB716302
文摘In recent several years,some works have been done on cosmic thermodynamics.The apparent horizonwas regarded as the key characteristic supersurface where thermodynamics can be built on perfectly.However,if theirreversible process is considered,the proper position for building thermodynamics will not be the apparent horizonanymore.The new position is related to dark energy state equation and the irreversible process parameters.
文摘This paper presents a weakly nonlinear water wave model using a mild slope equation and a new explicit formulation which takes into account dispersion of wave phase velocity, approximates Hedges’ (1987) nonlinear dispersion relationship, and accords well with the original empirical formula. Comparison of the calculating results with those obtained from the experimental data and those obtained from linear wave theory showed that the present water wave model considering the dispersion of phase velocity is rational and in good agreement with experiment data.
文摘Diesel Particulate Matter (DPM) is regulated in the U.S. for both underground coal and metal/nonmetal mines. Today, many underground mines still face difficulty in compliance with DPM regulations. The DPM research carried out in Missouri University of Science and Technology (MST) is to use computational fluid dynamics (CFD) to study the DPM distribution in commonly used face areas. The result is expected to be used for selection of DPM reduction strategies and better working practices, which can help the underground mines to meet regulation limits and improve the working environment for the miners. An experiment was conducted at MST's Experimental Mine to validate CFD simulation. DPM was collected at four locations downstream of a stationary diesel engine. The experiment data were then compared with the CFD simulation results. The comparison shows that CFD simulation can forecast the location of DPM concentration with practical accuracy (less than 0.15 m). CFD can be used to further study DPM distribution in commonly used working faces and give guidance to DPM reduction.
文摘Geologists can offer key insights in regard to several high profile environmental issues that are faced today. At the same time, like scientists in most other disciplines, many geologists are not naturally adept at communicating in an effective manner with non-geologists. This paper firstly identifies the more subtle facets of topical major issues (the drivers) where geologists can contribute important perspectives. Next, the detractions to effective communication are identified, along with the recommended means to overcome them (the mechanisms). Many topical issues are in fact geologically-underpinned (e.g. obviously, geohazards), so geologists ought to have something meaningful to say. By the same token, if geologists have difficulty communicating with other scientists, how can they possibly hope to communicate with journalists and with the public at large? Proper scientific contextualization is an ideal starting point, but this fundamental framing step does not always suit protagonists who have non-scientific agendas. Thus, geologists not only have to convey their science (geology) in an understandable way, but to do so in a truly effective manner must recognize and take into account possible predispositions that their audience may have.
文摘The non-coupled charge explosion and geo-mechanical dynamics problem in real air condition is studied in this paper. It analyzes and calculates the problem by using the real air state equations. Through researching on the non-coupled charge rock bench blasting with big clearance of air, its result indicates that the borehole wall reflection overpressure is far higher than strength of rock, but much lower than detonation front pressure of the charge. So non-coupled charge explosion blasting engineering is very successful. Furthermore, it introduces the method of shaft forming by blasting once and the new tube room technology. And the non-coupled charge explosion is used successfully in the method of shaft forming by blasting once. As it drills and blasts in the top and removes the broken rock from the bottom tunnel, it increases the construction efficiency significantly. This paper has important reference on the improvement of the large-span underground engineering construction.
文摘Elimination of human losses is the main and immediate task in the seismic vulnerability problem.The authors suggest the ways of development of seismic research and discussion of defense problems for reducing of seismic vulnerability. It is the ways of nonlinear seismology region. Unconditionally seism zoning and the theory of catastrophes allow reduce human losses and building destruction. But well-known isoseists are the private case of caustic catastrophe theory or seismo-acoustics, so seism zoning can be amounted to 6 elementary catastrophe forms. It will better help to predict seismic actions. The short-time local prediction of seismic events is general method for strong reducing of human losses. This method takes into account chaotic properties of stress fields and waves and the peculiarities of urban area. It bases on the natural seismo-emission phenomenon and is realized by long-time monitoring, which gives statistically and geographically continuous picture (chart) of seismic noise level inside geologic media. The instruments of this strategy are shock and pressure-proofed seismometers for long-time monitoring and control the state of geological media including underwater shelf areas. The authors think that the active protecting for cities and buildings as the best modem form of people safety consists in stress discharge of geologic media. Ultrasonic wave defense includes and bases on strong interaction between powerful waves from earthquake and ultrasonic wave train. The authors want to point out that the technical objects may be used lbr the investigation of earthquakes induced and some reasons of seismic vulnerability. Also reducing of seismic vulnerability contains as component kinetic acting on volcano at the pre-explosive stage. The interesting and important aspect of defense problem is observation of the inharmonic wave processes in the soil and quasi-constant forces as the nearest seismic analogue of radiation forces in nonlinear acoustics under powerful earthquake seismic tremor.
文摘During underground coal gasification (UCG), whereby coal is converted to syngas in situ, a cavity is formed in the coal seam. The cavity growth rate (CGR) or the moving rate of the gasification face is affected by controllable (operation pressure, gasification time, geometry of UCG panel) and uncontrollable (coal seam properties) factors. The CGR is usually predicted by mathematical models and laboratory experiments, which are time consuming, cumbersome and expensive. In this paper, a new simple model for CGR is developed using non-linear regression analysis, based on data from 1 l UCG field trials. The empirical model compares satisfactorily with Perkins model and can reliably predict CGR.
基金Supported by the New Century Excellent Talent Foundation from MOE of China(NCET-09-0844)the National Natural Science Foundation of China(50804060,50621403)
文摘Combining the field monitoring results of a deep-buried tunnel in Chongqing,the dynamic characteristics of the surrounding rock system under high in situ stress wasanalyzed by phase space reconstruction, calculating correlation dimension, Kolmogoroventropy and largest Lyapunov exponents.Both the Kolmogorov entropy and largestLyapunov exponents show that the surrounding rock system is a chaotic one.Based onthis, a local model was applied to predict surrounding rock displacement, and a nonlineardynamic model was derived to forecast the interaction of the surrounding rock and supportstructure.The local method was found to have an extremely small total error.Also, thenonlinear dynamic model forecasting curves agree with the monitoring ones very well.It isproved that the nonlinear dynamic characteristic study is very important in analyzing rockstability and predicting the evolution of rock systems.
基金funded by the Special Research Fund for Seismology(201408020)the Natural Science Foundation of China (51578514,U1434210)
文摘Ground motions are significantly influenced by dynamic characteristics of overburden soil layers near ground surface,as thick and soft soil layers would obviously amplify the ground motion strength. The conventional research method on soil nonlinear dynamic characteristics under strong motions is based on experiments in laboratories for the deficiency of observation data,but it is difficult to reliably simulate the complex factors of soils in actual earthquake durations,including loading paths,boundary conditions,and drainage conditions. The incremental data of the vertical downhole observation array,which is comprised of at least one observation point on ground surface and one observation point in a downhole rock base, makes it possible to study soil nonlinear dynamics according to in situ observation data,and provides new basic data and development opportunities to soil nonlinear dynamics studies.
文摘Over the last 30 years, environmental philosophers and ecological researchers have turned their attention to the possibilities of narratives: the stories people tell about their lives in conjunction with the human and non-human agents they live with. An interest in narrative environmental ethics reflects a re-evaluation of canonical ecophilosophical texts. Works such as Paul W. Taylor's Respect for Nature suggest an essentialist view of environmental ethics in which predetermined principles are imposed on places and situations. On the other hand, Aldo Leopold's A Sand County Almanac combines first-person prose with science-based explanations of the "biotic pyramid" towards the development of a land ethic. Examples, such as Leopold's, of narrative ethics are thought to offer relational, place-based, non-authoritative, and non-anthropocentric models. This article examines three critical components of environmental narratives: self, context, and tradition. In order for environmental narratives to advance ecological ethics, they must be accompanied by the tradition of natural science (geology, ecology, and evolution) to provide the "sponsoring ground" for ethical concern and action. The role of natural science as a tradition--and indeed one of many--in narrative ethics provides the basis for ecological selfhood in the context of place. These assertions will be supported by an analysis of the environmental narratives of Karen Warren and Jim Cheney. However, in the temporally expansive and ecologically conscious poetic narratives of John Kinsella we find an environmental ethics deeply rooted in the material realities of place.
基金supported by the National Natural Science Foundation of China(No.11526123,No.11401273)the Natural Science Foundation of Shandong Province of China(No.ZR2015PA010)
文摘Let A and B be two factor von Neumann algebras. For A, B ∈ A, define by [A, B]_*= AB-BA~*the skew Lie product of A and B. In this article, it is proved that a bijective map Φ : A → B satisfies Φ([[A, B]_*, C]_*) = [[Φ(A), Φ(B)]_*, Φ(C)]_*for all A, B, C ∈ A if and only if Φ is a linear *-isomorphism, or a conjugate linear *-isomorphism, or the negative of a linear *-isomorphism, or the negative of a conjugate linear *-isomorphism.
基金financially supported by the"Wenchuan Earthquake Fault Scientific Drilling"of the National Science and Technology Planning Project,Sinoprobe Deep Exploration in China Project(Grant No.SinoProbe-07)Fundamental Research Fund for Chinese Academy of Geological Sciences(Grant No.SYS1301)+1 种基金Grant-in-Aid for Scientific Research of Japan Society for the Promotion of Science(JSPS)(Grant No.25287134)Ministry of Education,Culture,Sports,Science and Technology(MEXT),Japan(Grant No.21107006)
文摘In situ stress state becomes more and more significant with in-depth research on geodynamics and energy development.However,there has not been an economic and effective method developed to determine deep three-dimensional in situ stress.The Anelastic Strain Recovery(ASR)method is a newly developed technique that can determine three-dimensional in situ stresses.After the 12 May 2008 Ms8.0 Wenchuan earthquake,the ASR method was used for the first time in China's Mainland to measure the in situ stresses in the WFSD scientific boreholes in Sichuan Province,China.In this paper,the basic procedure of the ASR method is introduced in detail and the compliances of ASR for boring cores are investigated.The results show that the maximum principal stress direction was NW64°at a measured depth(MD)of 1173 m(vertical depth 1151 m)in WFSD-1.The ratio of shear mode to the volume mode compliance of ASR was 2.9.And the three principal stresses at 1173 m MD in WFSD-1are 43,28 and 25 MPa.Combined with stress measurement results determined using other in situ measurement methods along the Longmenshan fault zone,the directions of the maximum horizontal principal stress changes from E-W to NEE-SWW to NWW-SEE when moving from NE to SW along the Longmenshan fault zone.This change is in agreement with the stress regime of the Longmenshan fault zone of the Wenchuan Earthquake,which supports a stress regime consisting predominantly of thrusts in the southwest and strike-slip in the northeast.
文摘A nonlinear mathematical model is proposed and analyzed to study the dynamics of 2009 HIN1 flu epidemic in a homogeneous population with constant immigration of susceptibles. The effect of contact tracing and quarantine (isolation) strategies in reduc- ing the spread of H1N1 flu is incorporated. The model monitors the dynamics of five sub-populations (classes), namely susceptible with high infection risk, susceptible with reduction of infection risk, infective, quarantined and recovered individuals. The model analysis includes the determination of equilibrium points and carrying out their stability analysis in terms of the threshold parameter R0. Moreover, the numerical simulation of the proposed model is also performed by using fourth order Runge-Kutta method along with the sensitivity analysis of the endemic equilibrium point. The analysis and numeri- cal simulation results demonstrate that the maximum implementation of contact tracing and quarantine strategies help in reducing endemic infective class size and hence act as effective intervention strategy to control the disease. This gives a theoretical interpreta- tion to the practical experiences that the early contact tracing and quarantine strategies are criticMly important to control the outbreak of epidemics.
基金supported by Sino-Africa Joint Research Center(Y323771W07,SAJC201322)the National Natural Science Foundation of China(31300182)
文摘East Africa is a biodiversity hotspot. Haplocarpha rueppelii (Sch.Bip.) Beauverd is mainly distributed in the alpine grassland of East Africa. Here we sampled 65 individuals of eight populations/locations of H. rueppelii including hairy and glabrous forms from Mts. Elgon, Aberdare, Kenya, Kilimanjaro and Bale Mountains. We then sequenced one nuclear and three chloroplast DNA fragments and conducted phylogeographic analyses to test the taxonomic rank of the two forms and causes for the differentiation (intrinsic reproductive isolation and geographic barrier). The results demonstrate that the species consists of two major groups, one includes the populations from Mts. Elgon, Aberdare and Bale, while the other includes Mts. Kenya and Kilimanjaro. The species has established in Mts. Kenya and Aberdare during the Pleistocene. However, migration rate for individuals between the two mountains was low as showed by gene flow analysis. A barrier for plant dispersal and gene flow would have existed between Mts. Aberdare and Kenya since at least Pleistocene. No change of the taxonomic concept of this species is needed. This study reveals a potential geographic barrier in East Africa. We hope it will arouse more scientists' interests in phylogeography and biodiversity of East Africa.
文摘Target-mediated drug disposition (TMDD)model is one of the main modeling theories for studying nonlinear pharmacokinetics (PK)ofmonoclonal antibodies.However,there are too many parameters in full TMDD model to be estimated based on limited clinical data,leading to instability of the final model.In the present study,we analyzed the predictive ability and applicability of a simplified quasi-steady state (QSS)model with the assumption that the total target concentration was a constant parameter during treatment with monoelonal antibody in clinical data modeling.Based on the parameters of a published TMDD model of denosumab,simulations were performed at population and individual levels.Then,a simplified TMDD model,QSS model, was used to examine the effects of hypotheses,in which the total receptor concentration was constant or variable on model fit and stability of parameter estimation.Both simulations at the population level and model fit results of simulated individual data showed that at the therapeutic doses,the total receptor concentration had little influence on changes in drug concentration,and the model with constant total receptor concentration had the same predictive power.The validated hypothesis could be applied to clinical trial design and selection of the optimal PK model in the development of monoclonal antibodies.