The comprehensive carrying capacity of urban land can reflect the re- source level, economic scale, social development and environmental pressure of ur- ban land carrying. The assessment indicator system of urban land...The comprehensive carrying capacity of urban land can reflect the re- source level, economic scale, social development and environmental pressure of ur- ban land carrying. The assessment indicator system of urban land comprehensive carrying capacity was constructed from the 4 aspects of resource, economy, society, environment, and principal component analysis and cluster analysis were used to evaluate the urban land comprehensive carrying capacity of Guangxi and the 14 cities in 2005-2014, and analyzed its spatial and temporal characteristics as well as the driving forces, with the aim to provide references for improving the urban land comprehensive carrying capacity. The results showed that, the overall urban land comprehensive carrying capacity in Guangxi increased in 2005-2014, and there were significant differences in the land comprehensive carrying capacities among the cities in Guangxi in 2005-2014, in which Liuzhou, Guilin, Nanning belonged to the regions with the highest carrying capacity, while Beihai, Yulin, Wutong belonged to the regions with high carrying capacity, and the carrying capacities of the other cities changed with the changes of time. The economic development degree was an important factor influencing urban land comprehensive carrying capacity, but could not directly represent the urban land comprehensive carrying capacity level.展开更多
为解决Navi-Trainer Professional 5000型全任务大型船舶操纵模拟器无法识别S-57数据格式,致使最新的官方电子海图(ENC)数据文件无法直接应用的问题,采用Scene Editor软件进行海图数据转换,克服船舶操纵模拟器电子海图数据间不融合的问...为解决Navi-Trainer Professional 5000型全任务大型船舶操纵模拟器无法识别S-57数据格式,致使最新的官方电子海图(ENC)数据文件无法直接应用的问题,采用Scene Editor软件进行海图数据转换,克服船舶操纵模拟器电子海图数据间不融合的问题。以天津港附近水域海图文件转换为例,验证Scene Editor软件进行海图数据转换具有可行性,说明基于ENC数据文件的三维实景建模可广泛应用于船舶操纵的教学、科研和培训。展开更多
The elevation of Qinghai\|Tibetan plateau is a epoch\|making event in the global evolutionary history, which not only constructed the modern magnificent geomorphic feature, but also influenced far\|reachingly the glob...The elevation of Qinghai\|Tibetan plateau is a epoch\|making event in the global evolutionary history, which not only constructed the modern magnificent geomorphic feature, but also influenced far\|reachingly the global climate. The evolutionary models of its uplifting time and scope has been primarily set up, and is waiting to be competed with new discovery and supplement. A comprehensive field geologic excursion on the Cenozoic strata of the Kumukuli basin, Xinjiang, northwest Qinghai\|Tibetan plateau by authors has collected a lot of first\|hand data, and the discovery and dating of the late Pleistocene mammal fossils made an important supplement to the scarcity of late Quaternary fossil recorders in many basins, as well as contributed a great deal to the quantitative study of the researches alike, in the main time, provided new evidences to the uplift of Qinghai\|Tibetan plateau since late pleistocene.Lies in the northwest part of the Qinghai\|Tibetan plateau, and between the Kunlun and Altum Mountain ranges, Kumukuli basin is a intracontinental plateau basin, with a mean elevation about 4000m. Cenozoic strata have a time span from Oligocene to Pleistocene.The stratigraphic and lithologic association displays that the development of Kumukuli basin started at the Oligocene, at the primary uplift stage of the Qinghai\|Tibetan plateau. The Oligocene and Miocene, with a giant thickness and multiple layers of thick conglomerate, is of the products of stronger erosional stage, and a reflection of higher differential in inner geomorphology of the plateau. The aggradation led to the smoothness of the geomorphic feature and fineness of sedimentary particle since Pliocene. Since then, Large scale conglomerate outcroped in the peripheral of the plateau, and differential of geomorphology in the plateau and its peripheral areas became distinct. Kumukuli basin is one of the synchronously developed basin with the plateau, having the most completed Cenozoic sequence with a thickness over 7000m. Its Tertiary sedimentary sequence is basically similar to that of the Ningxia basin, northeastern margin of the Qinghai\|Tibetan plateau, and can be well correlated each other, mutually, they recorded the uplift process of the Qinghai\|Tibetan plateau, and their difference may represent the contrast evolution of the plateau and inhomogeneous differential in geomorphic feature of the plateau and its perimeter respectively. Being two sedimentary basins in separately tectonic units, the former has much thicker strata and coarser particles, for instance, the Oligocene is over 3000m in thickness in Kumukuli basin, however, only about 100m in Ningxia basin. Several uncomformities occurring in Kumukuli basin, namely, between the Quarternary and the Pliocene, the Pliocene and the Middle\|Upper Miocene, as well as the Middle\|Upper Miocene and the Lower Miocene, are the direct effects of horizontal movement accompanied with the process of the uplift of the Qinghai\|Tibetan plateau. Maybe those data imply that the western part of the plateau much stronger in uplift and distinct in horizontal movement than that of the east.展开更多
Chaotic vibrations of flexible non-linear Euler-Bernoulli beams subjected to harmonic load and with various boundary conditions（symmetric and non-symmetric）are studied in this work.Reliability of the obtained result...Chaotic vibrations of flexible non-linear Euler-Bernoulli beams subjected to harmonic load and with various boundary conditions（symmetric and non-symmetric）are studied in this work.Reliability of the obtained results is verified by the finite difference method（FDM）and the finite element method（FEM）with the Bubnov-Galerkin approximation for various boundary conditions and various dynamic regimes（regular and non-regular）.The influence of boundary conditions on the Euler-Bernoulli beams dynamics is studied mainly,dynamic behavior vs.control parameters { ωp,q0 } is reported,and scenarios of the system transition into chaos are illustrated.展开更多
The correlated spectroscopy revamped by asymmetric Z-gradient echo detection （CRAZED） sequence is modified to investigate intermolecular double-quantum coherence nuclear magnetic resonance signal dips in highly pola...The correlated spectroscopy revamped by asymmetric Z-gradient echo detection （CRAZED） sequence is modified to investigate intermolecular double-quantum coherence nuclear magnetic resonance signal dips in highly polarized spin systems. It is found that the occurrence of intermolecular double-quantum coherence signal dips is related to sample geometry, field inhomogeneity and dipolar correlation distance. If the field inhomogeneity is refocused, the signal dip occurs at a fixed position whenever the dipolar correlation distance approaches the sample dimension. However, the position is shifted when the field inhomogeneity exists. Experiments and simulations are performed to validate our theoretic analysis. These signal features may offer a unique way to investigate porous structures and may find applications in biomedicine and material science.展开更多
基金Supported by the Open Bidding Projects of the Office of Land and Resources of the Guangxi Zhuang Autonomous Region(GXZC2015-G3-0575-GTZB)~~
文摘The comprehensive carrying capacity of urban land can reflect the re- source level, economic scale, social development and environmental pressure of ur- ban land carrying. The assessment indicator system of urban land comprehensive carrying capacity was constructed from the 4 aspects of resource, economy, society, environment, and principal component analysis and cluster analysis were used to evaluate the urban land comprehensive carrying capacity of Guangxi and the 14 cities in 2005-2014, and analyzed its spatial and temporal characteristics as well as the driving forces, with the aim to provide references for improving the urban land comprehensive carrying capacity. The results showed that, the overall urban land comprehensive carrying capacity in Guangxi increased in 2005-2014, and there were significant differences in the land comprehensive carrying capacities among the cities in Guangxi in 2005-2014, in which Liuzhou, Guilin, Nanning belonged to the regions with the highest carrying capacity, while Beihai, Yulin, Wutong belonged to the regions with high carrying capacity, and the carrying capacities of the other cities changed with the changes of time. The economic development degree was an important factor influencing urban land comprehensive carrying capacity, but could not directly represent the urban land comprehensive carrying capacity level.
文摘为解决Navi-Trainer Professional 5000型全任务大型船舶操纵模拟器无法识别S-57数据格式,致使最新的官方电子海图(ENC)数据文件无法直接应用的问题,采用Scene Editor软件进行海图数据转换,克服船舶操纵模拟器电子海图数据间不融合的问题。以天津港附近水域海图文件转换为例,验证Scene Editor软件进行海图数据转换具有可行性,说明基于ENC数据文件的三维实景建模可广泛应用于船舶操纵的教学、科研和培训。
文摘The elevation of Qinghai\|Tibetan plateau is a epoch\|making event in the global evolutionary history, which not only constructed the modern magnificent geomorphic feature, but also influenced far\|reachingly the global climate. The evolutionary models of its uplifting time and scope has been primarily set up, and is waiting to be competed with new discovery and supplement. A comprehensive field geologic excursion on the Cenozoic strata of the Kumukuli basin, Xinjiang, northwest Qinghai\|Tibetan plateau by authors has collected a lot of first\|hand data, and the discovery and dating of the late Pleistocene mammal fossils made an important supplement to the scarcity of late Quaternary fossil recorders in many basins, as well as contributed a great deal to the quantitative study of the researches alike, in the main time, provided new evidences to the uplift of Qinghai\|Tibetan plateau since late pleistocene.Lies in the northwest part of the Qinghai\|Tibetan plateau, and between the Kunlun and Altum Mountain ranges, Kumukuli basin is a intracontinental plateau basin, with a mean elevation about 4000m. Cenozoic strata have a time span from Oligocene to Pleistocene.The stratigraphic and lithologic association displays that the development of Kumukuli basin started at the Oligocene, at the primary uplift stage of the Qinghai\|Tibetan plateau. The Oligocene and Miocene, with a giant thickness and multiple layers of thick conglomerate, is of the products of stronger erosional stage, and a reflection of higher differential in inner geomorphology of the plateau. The aggradation led to the smoothness of the geomorphic feature and fineness of sedimentary particle since Pliocene. Since then, Large scale conglomerate outcroped in the peripheral of the plateau, and differential of geomorphology in the plateau and its peripheral areas became distinct. Kumukuli basin is one of the synchronously developed basin with the plateau, having the most completed Cenozoic sequence with a thickness over 7000m. Its Tertiary sedimentary sequence is basically similar to that of the Ningxia basin, northeastern margin of the Qinghai\|Tibetan plateau, and can be well correlated each other, mutually, they recorded the uplift process of the Qinghai\|Tibetan plateau, and their difference may represent the contrast evolution of the plateau and inhomogeneous differential in geomorphic feature of the plateau and its perimeter respectively. Being two sedimentary basins in separately tectonic units, the former has much thicker strata and coarser particles, for instance, the Oligocene is over 3000m in thickness in Kumukuli basin, however, only about 100m in Ningxia basin. Several uncomformities occurring in Kumukuli basin, namely, between the Quarternary and the Pliocene, the Pliocene and the Middle\|Upper Miocene, as well as the Middle\|Upper Miocene and the Lower Miocene, are the direct effects of horizontal movement accompanied with the process of the uplift of the Qinghai\|Tibetan plateau. Maybe those data imply that the western part of the plateau much stronger in uplift and distinct in horizontal movement than that of the east.
文摘Chaotic vibrations of flexible non-linear Euler-Bernoulli beams subjected to harmonic load and with various boundary conditions（symmetric and non-symmetric）are studied in this work.Reliability of the obtained results is verified by the finite difference method（FDM）and the finite element method（FEM）with the Bubnov-Galerkin approximation for various boundary conditions and various dynamic regimes（regular and non-regular）.The influence of boundary conditions on the Euler-Bernoulli beams dynamics is studied mainly,dynamic behavior vs.control parameters { ωp,q0 } is reported,and scenarios of the system transition into chaos are illustrated.
基金supported by the National Natural Science Foundation of China (Grant Nos. 10875101 and 11074209)the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20090121110030)
文摘The correlated spectroscopy revamped by asymmetric Z-gradient echo detection （CRAZED） sequence is modified to investigate intermolecular double-quantum coherence nuclear magnetic resonance signal dips in highly polarized spin systems. It is found that the occurrence of intermolecular double-quantum coherence signal dips is related to sample geometry, field inhomogeneity and dipolar correlation distance. If the field inhomogeneity is refocused, the signal dip occurs at a fixed position whenever the dipolar correlation distance approaches the sample dimension. However, the position is shifted when the field inhomogeneity exists. Experiments and simulations are performed to validate our theoretic analysis. These signal features may offer a unique way to investigate porous structures and may find applications in biomedicine and material science.
