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视差立体图像的生成算法 被引量:7
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作者 汪明霓 《杭州师范学院学报(自然科学版)》 CAS 2004年第5期420-422,共3页
阐述视差立体图像的原理和设计方法,介绍几种特殊的视差立体图像,包括连续∑面视差立体图像、大幅面视差立体图像和可双向观察的视差立体图像.
关键词 视差 立体图像 算法 随机点 连续∑面 双向观察
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Direct-chill semi-continuous casting process of three-layer composite ingot of 4045/3004/4045 aluminum alloys 被引量:5
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作者 蒋会学 张海涛 +1 位作者 秦克 崔建忠 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第8期1692-1697,共6页
Three-layer composite ingot of 4045/3004/4045 aluminum alloys was prepared by direct-chill semi-continuous casting process,the temperature field distribution near the composite interface,macro-morphology,microstructur... Three-layer composite ingot of 4045/3004/4045 aluminum alloys was prepared by direct-chill semi-continuous casting process,the temperature field distribution near the composite interface,macro-morphology,microstructure and composition distribution of the composite interface were investigated.The results show that semi-solid layer with a certain thickness forms near the interface due to the effect of cooling plate,which ensures successful implementation of casting the composite ingot.Two different aluminum alloys are well bonded metallurgically.The mechanical properties of composite interface were measured,the tensile and shearing strengths of composite interface are 105 and 88 MPa,respectively,which proves that the composite interface is a kind of metallurgical bonding. 展开更多
关键词 aluminum alloys three-layer composite ingot direct-chill semi-continuous casting composite interface structures properties
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Critical load position for cavities beneath CRCP slab under vehicle loading 被引量:2
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作者 陈小兵 赵蓉龙 +2 位作者 童金虎 黄晓明 罗瑞林 《Journal of Southeast University(English Edition)》 EI CAS 2016年第1期78-84,共7页
In order to study the critical load position that causes cavities beneath the continuously reinforced concrete pavement( CRCP) slab under vehicle loading, the elliptical load is translated into the square load based... In order to study the critical load position that causes cavities beneath the continuously reinforced concrete pavement( CRCP) slab under vehicle loading, the elliptical load is translated into the square load based on the equivalence principle.The CRCP slab is analyzed to determine the cavity position beneath the slab under vehicle loading. The influences of cavity size on the CRCP slab's stress and vertical displacement are investigated. The study results showthat the formation of the cavity is unavoidable under traffic loading, and the cavity is located at the edge of the longitudinal crack and the slab corner.The cavity size exerts an obvious influence on the largest horizontal tensile stress and vertical displacement. The slab corner is the critical load position of the CRCP slab. The results can be used to assist the design of CRCP in avoiding cavities beneath slabs subject to vehicle loading. 展开更多
关键词 vehicle loading CAVITY continuously reinforced concrete pavement(CRCP) critical load position finite element method(FEM)
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Constructing G^1 interpolation curves on surfaces with Coons surface
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作者 王小平 周儒荣 +1 位作者 王志国 张丽艳 《Journal of Southeast University(English Edition)》 EI CAS 2004年第2期187-190,共4页
Using a bi-cubic Coons surface, a method for G1-continuous interpolation of an arbitrary sequence of points on an implicitly or parametrically defined surface with a specified tangent direction at every point was pres... Using a bi-cubic Coons surface, a method for G1-continuous interpolation of an arbitrary sequence of points on an implicitly or parametrically defined surface with a specified tangent direction at every point was presented. Firstly construct a G1-continuous composite Coons surface patch, and then compute the intersection of the surface patch and the given surface. The desired interpolation curve is the intersection curve. Unlike some existing methods, several free parameters were introduced into the method that can be used in subsequent interactive modification so that the last curve's shape meets the demand. Experiments demonstrate the method is simple, feasible and applicable to computer aided design and computer graphics, etc. 展开更多
关键词 Computer graphics INTERSECTIONS Matrix algebra
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The Order of Approximation by Complex Rational Type Interpolating Operators at Fejer's Points 被引量:1
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作者 王子玉 朱长青 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第3期66-70,共5页
In this paper, supose Γ be a boundary of a Jordan domain D and Γ satisfied Альпер condition, the order that rational type interpolating operators at Fejer's points of f(z)∈C(Γ) converge to f(z) in the se... In this paper, supose Γ be a boundary of a Jordan domain D and Γ satisfied Альпер condition, the order that rational type interpolating operators at Fejer's points of f(z)∈C(Γ) converge to f(z) in the sense of uniformly convergence is obtained. 展开更多
关键词 rational type interpolation Fejer's points order of approximation Jordan domain
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Design and Realization of CPW Circuits Using EC-ANN Models for CPW Discontinuities
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作者 胡江 孙玲玲 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第12期2320-2329,共10页
Novel accurate and efficient equivalent circuit trained artificial neural-network (EC-ANN) models,which inherit and improve upon EC model and EM-ANN models' advantages,are developed for coplanar waveguide (CPW) d... Novel accurate and efficient equivalent circuit trained artificial neural-network (EC-ANN) models,which inherit and improve upon EC model and EM-ANN models' advantages,are developed for coplanar waveguide (CPW) discontinuities. Modeled discontinuities include : CPW step, interdigital capacitor, symmetric cross junction, and spiral inductor, for which validation tests are performed. These models allow for circuit design, simulation, and optimization within a CAD simulator. Design and realization of a coplanar lumped element band pass filter on GaAs using the developed CPW EC-ANN models are demonstrated. 展开更多
关键词 CPW DISCONTINUITIES MODELS equivalent circuit artificial neural-network band pass filter
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Development of an automated system for continuous monitoring of powered roof support in longwall panel 被引量:1
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作者 ATULKumar DHEERAJKumar +1 位作者 SINGHU.K. GUPTAP.S. 《Journal of Coal Science & Engineering(China)》 2010年第4期337-340,共4页
Described the development of an Intrinsically Safe System for continuous monitoring of load and convergence of powered roof supports installed at Iongwall faces. The system developed for monitoring of behavior of a po... Described the development of an Intrinsically Safe System for continuous monitoring of load and convergence of powered roof supports installed at Iongwall faces. The system developed for monitoring of behavior of a powered support in a mechanized Iongwall sublevel caving face. The logging system can be programmed for logging the data from the sensors at different logging intervals ranging from 16 h to 1 ms for logging variation in hydraulic pressures in legs and convergence of the support during progressive face advance. For recording dynamic loads, the data logger can be programmed to start fast logging, say at 10 ms intervals, when the pressure in a leg reaches a pre-specified threshold value, and continue fast logging until the pressure drops below this threshold value. This fast logging automatically stops when the pressure drops below this threshold value. 展开更多
关键词 data logging system CONVERGENCE leg pressure software analysis
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Reconstruction from contour lines based on bi-cubic Bézier spline surface 被引量:1
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作者 LI Zhong MA Li-zhuang +1 位作者 TAN Wu-zheng ZHAO Ming-xi 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第7期1241-1246,共6页
A novel reconstruction method from contours lines is provided. First, we use a simple method to get rid of redundant points on every contour, then we interpolate them by using cubic Bézier spline curve. For corre... A novel reconstruction method from contours lines is provided. First, we use a simple method to get rid of redundant points on every contour, then we interpolate them by using cubic Bézier spline curve. For corresponding points of different con- tours, we interpolate them by the cubic Bézier spline curve too, so the whole surface can be reconstructed by the bi-cubic Bézier spline surface. The reconstructed surface is smooth because every Bézier surface is patched with G2 continuity, the reconstruction speed is fast because we can use the forward elimination and backward substitution method to solve the system of tridiagonal equations. We give some reconstruction examples at the end of this paper. Experiments showed that our method is applicable and effective. 展开更多
关键词 CONTOUR Surface reconstruction Bi-cubic Bézier surface G^2 continuity
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Temperature field evolution and heat transfer during continual local induction cladding 被引量:3
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作者 LIU Si-yu QIN Xun-peng +1 位作者 ZHANG Jin-peng ZHAN Jun 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第5期1572-1586,共15页
The evolution of temperature field of the continual motion induction cladding and the depth of heat affected zone are studied in this study.A three-dimensional finite element model for the point type continual inducti... The evolution of temperature field of the continual motion induction cladding and the depth of heat affected zone are studied in this study.A three-dimensional finite element model for the point type continual induction cladding is established to investigate temperature distributions of fixed and motion induction cladding modes.The novel inductor is designed for cladding of curved surfaces.The modeling reliability is verified by the temperature measurements.The influence of process parameters on the maximum temperature and the generation and transfer of heat are studied.Quantitative calculation is performed to its melting rate to verify the temperature distribution and microstructures.The results show that a good metallurgical bond can be formed between the cladding layer and substrate.The melting rate gradually falls from the top of the cladding layer to the substrate,and the grain size in the substrate gradually rises.The heat affected zone is relatively small compared to integral heating. 展开更多
关键词 profile repair induction cladding continual motion temperature field evolution heat transfer
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A New Approach to Plane Failure of Rock Slope Stability Based on Water Flow Velocity in Discontinuities for the Latian Dam Reservoir Landslide 被引量:3
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作者 Morteza AHMADI Majid ESLAMI 《Journal of Mountain Science》 SCIE CSCD 2011年第2期124-130,共7页
The stability of slopes is always of great concern in the field of rock engineering. The geometry and orientation of pre-existing discontinuities show a larger impact on the behavior of slopes that is often used to de... The stability of slopes is always of great concern in the field of rock engineering. The geometry and orientation of pre-existing discontinuities show a larger impact on the behavior of slopes that is often used to describe the measurement of the steepness, incline, gradient, or grade of a straight line. One of the structurally controlled modes of failure in jointed rock slopes is plane failure. There are numerous analytical methods for the rock slope stability including limit equilibrium, stress analysis and stereographic methods. The limiting equilibrium methods for slopes under various conditions against plane failure have been previously proposed by several investigators. However, these methods do not involve water pressure on sliding surfaces assessments due to water velocity and have not yet been validated by case study results. This paper has tried to explore the effects of forces due to water pressure on discontinuity surfaces in plane failure through applying the improved equations. It has studied the effect of water flow velocity on sliding surfaces in safety factor, as well. New equations for considering water velocity (fluid dynamics) are presented. To check the validity of the suggested equations, safety factor for a case study has been determined. Results show that velocity of water flow had significant effect on the amount of safety factor. Also, the suggested equations have higher validity rate compared to the current equations. 展开更多
关键词 Plane Failure Limit Equilibrium Safety Factor Water Velocity
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Dynamic Instability of Tunnel in Blocky Rock Mass
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作者 戚承志 陈灿寿 +1 位作者 钱七虎 罗健 《Transactions of Tianjin University》 EI CAS 2008年第6期457-463,共7页
The displacements and geometry of the rock blocks and the properties of the rock struc-ture play an important role in the stability of tunnels.Based on the key block model,the dynamic instability analysis of undergrou... The displacements and geometry of the rock blocks and the properties of the rock struc-ture play an important role in the stability of tunnels.Based on the key block model,the dynamic instability analysis of underground tunnel subjected to intensive short-time compressional wave was conducted.The instability of the tunnel caused by the spallation and the inertial effect was distin-guished.And the influence of the roof contour curvature of tunnel was also determined. 展开更多
关键词 blocky rock mass dynamic instability discontinuity surfaces key block
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3-D reconstruction of coastal bathymetry from AIRSAR/POLSAR data 被引量:1
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作者 Maged MARGHANY Mazlan HASHIM Arthur P. CRACKNELL 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第1期117-123,共7页
This paper introduces a new method for reconstructing three-dimensional (3D) coastal bathymetry changes from Airborne AIRSAR/POLSAR synthetic aperture data. The new method is based on integration between fuzzy B-spl... This paper introduces a new method for reconstructing three-dimensional (3D) coastal bathymetry changes from Airborne AIRSAR/POLSAR synthetic aperture data. The new method is based on integration between fuzzy B-spline and Volterra algorithm. Volterra algorithm is used to simulate the ocean surface current from AIRSAR/POLSAR data. Then, the ocean surface current information used as input for continuity equation to estimate the water depths from AIRSAR/POLSAR data. This study shows that 3D ocean bathymetry can be reconstructed from AIRSAR/POLSAR data with root mean square error of ±0.03 m. 展开更多
关键词 AIRSAR/POLSAR data Volterra algorithm Fuzzy B-spline 3D bathymetry
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One-dimensional nonlinear consolidation analysis of soil with continuous drainage boundary 被引量:7
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作者 ZONG Meng-fan TIAN Yi +3 位作者 LIANG Rong-zhu WUWen-bing XU Mei-juan MEI Guo-xiong 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第1期270-281,共12页
Following the assumptions proposed by MESRI and ROKHSAR,the one-dimensional nonlinear consolidation problem of soil under constant loading is studied by introducing continuous drainage boundary.The numerical solution ... Following the assumptions proposed by MESRI and ROKHSAR,the one-dimensional nonlinear consolidation problem of soil under constant loading is studied by introducing continuous drainage boundary.The numerical solution is derived by using finite difference method and its correctness is assessed by comparing with existing analytical and numerical solutions.Based on the present solution,the effects of interface parameters,stress ratios(i.e.,final effective stress over initial effective stress,N_(σ))and the ratio c_(c)/c_(k)of compression index to permeability index on the consolidation behavior of soil are studied in detail.The results show that,the characteristics of one-dimensional nonlinear consolidation of soil are not only related to c_(c)/c_(k)and N_(σ),but also related to boundary conditions.In the engineering practice,the soil drainage rate of consolidation process can be designed by adjusting the values of interface parameters. 展开更多
关键词 one-dimensional nonlinear consolidation continuous drainage boundary finite difference method interface parameter
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Optimal air-supply mode of hybrid system with radiant cooling and dedicated outdoor air 被引量:5
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作者 丁研 田喆 朱能 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第2期735-746,共12页
The hybrid system with radiant cooling and dedicated outdoor air not only possesses high energy efficiency, but also creates a healthy and comfortable indoor environment. Indoor air quality will be improved by the ded... The hybrid system with radiant cooling and dedicated outdoor air not only possesses high energy efficiency, but also creates a healthy and comfortable indoor environment. Indoor air quality will be improved by the dedicated outdoor air system(DOAS) and indoor thermal comfort can be enhanced by the radiant cooling system(RCS). The optimal air-supply mode of the hybrid system and the corresponding design approach were investigated. A full-scale experimental chamber with various air outlets and the ceiling radiant cooling panels(CRCP) was designed and established. The performances of different air-supply modes along with CRCPs were analyzed by multi-index evaluations. Preliminary investigations were also conducted on the humidity stratification and the control effect of different airflow modes to prevent condensation on CRCP. The overhead supply air is recommended as the best combination mode for the hybrid system after comprehensive comparison of the experiment results. The optimal proportion of CRCP accounting for the total cooling capacities in accord with specific cooling loads is found, which may provide valuable reference for the design and operation of the hybrid system. 展开更多
关键词 air-supply mode hybrid system radiant cooling humidity stratification
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Nonlinear Waves in Two-Dimensional (2D) Square Lattice Frenkel-Kontorova (FK) System
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作者 WANG Cang-Long HAN Jiu-Ning GAO Xiu-Yun DUAN Wen-Shant 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第1期90-96,共7页
A 2D square lattice is studied. By using the continuum approximation, we set up the differential equations of motion for an arbitrary particle in the square lattice which subjects to an external periodic substrate pot... A 2D square lattice is studied. By using the continuum approximation, we set up the differential equations of motion for an arbitrary particle in the square lattice which subjects to an external periodic substrate potential. The exact solitary waves of the system are found for special cases. We conclude that the adhesive force f and the angle between propagation directions of upper and lower layers can affect these waves. 展开更多
关键词 FK model square lattice solitary waves
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Antioxidant activity of phytosynthesized biomatrix-loaded noble metallic nanoparticles 被引量:1
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作者 Preeti Dauthal Mausumi Mukhopadhyay 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第5期1200-1208,共9页
Biofabrication of noble monometallic platinum nanoparticles(Pt-NPs) and bimetallic gold–silver nanoparticles(Au Ag-NPs) using aqueous extract of Delonix regia is presented here. Antioxidant activity of biomatrix-load... Biofabrication of noble monometallic platinum nanoparticles(Pt-NPs) and bimetallic gold–silver nanoparticles(Au Ag-NPs) using aqueous extract of Delonix regia is presented here. Antioxidant activity of biomatrix-loaded metallic nanoparticles is estimated for scavenging of two model radicals i.e., 2,2′-Azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt and 1,1′-Diphenyl-2-picrylhydrazyl. Broad spectral continuum spanning from visible to ultra-violet region(Pt-NPs: 30 min) and broad high intensity absorption peak around at 500 nm(Au Ag-NPs: 10 min) in two different UV–Visible spectra confirmed the biofabrication. Nanoparticles fabricated with distorted spherical shape and crystalline face-centred-cubic geometry. Strong signal around at 2.10 ke V(pure-phase platinum) and typical X-ray peaks observed at 2.20 and 3 ke V suggested, co-existence and alloying interaction of Au and Ag in Au Ag-NPs. ζ potential(-15.2 mV: Pt-NPs and -13.9 mV: Au Ag-NPs) values suggested surface adsorption of polyphenolic compounds to provide stability. Nanoparticles exhibited pronounced antioxidant activity against free radicals through their electron/hydrogen transfer ability. 展开更多
关键词 PLATINUM Gold-silver Nanopartides ANTIOXIDANT Free radical
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3eta Diversity of Mbuna in Lake Malawi
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作者 L.G. Kanyumba W.J. Changadeya +2 位作者 A.J.D. Ambali L.A. Kamwanja E.K.W. Kaunda 《Journal of Environmental Science and Engineering》 2011年第11期1496-1506,共11页
Molecular and field studies suggest that Mbuna have limited migration range and are restricted by habitat discontinuities especially in areas where rocky habitats are separated by stretches of sand. This study estimat... Molecular and field studies suggest that Mbuna have limited migration range and are restricted by habitat discontinuities especially in areas where rocky habitats are separated by stretches of sand. This study estimated regional diversity of Mbuna in Lake Malawi. The estimated fl-diversity for all sites was 114.5 Mbuna suggesting that there was high level of allopatrism for the species complex. Sympatric index was low in the two regions of southern and northern lake and the observed high-end richness strongly correlated with minimum species richness. The sympatric index for the whole lake was 0.8, with non-monotypic species complexes showing declining values of sympatric index and the decline was dependent on the geographical scale of the area covered. The northern region sites had mean habitat ranking of 84.5% while the southern sites had habitat ranking of 56.7% supporting the observation that there are more rocky habitats in the northern part of the lake than in the southern. Implications of habitat ranking are discussed in terms of species abundance and richness. 展开更多
关键词 Mbuna beta diversity species richness species abundance
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Michel Houellebecq: The Era of Emptiness
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作者 Ruth Amar 《Journalism and Mass Communication》 2016年第3期158-165,共8页
Michel Houellebecq is perhaps the most successful, the most famous and controversial of all current novelists writing in French. He has become a global publishing phenomenon: His books have been translated worldwide,... Michel Houellebecq is perhaps the most successful, the most famous and controversial of all current novelists writing in French. He has become a global publishing phenomenon: His books have been translated worldwide, film adaptations of his novels have been produced, and the author is the subject of a million-euro publishing deals and successive media scandals in France. The novels depict surprising forms of imaginary resources, a radiating end of the world, a post-nuclear anxiety, and depressive characters. Houellebecq shocks us leaving us in a world where the feelings of love, tenderness and goodwill have disappeared. The purpose of Houellebecq's novels is to alert about the real problems of the human society in the twenty-first century. Indeed, in the books we can easily recognize the essential features of contemporary society and the fact that the individual assumes a dehumanization process in which one has to cope with his solitude in a world of emptiness. This socio-cultural dimension is indeed the background of Houellebecq's novels, novels in which the protagonists seem to be wedged in a mechanism from which it is difficult to escape: reification and dehumanization on the one hand, "robotization" of love on the other. This article focuses on the analysis of the texts revealing the poignant characteristics of"L'Ere du vide" ("The Era of Emptiness") as described by Gilles Lipovetsky: Loneliness, the lack of love and its replacement by sexual relations. 展开更多
关键词 REIFICATION DEHUMANIZATION "robotization" "L'Ere du vide" LONELINESS lack of love sexual relations
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Primary Discussion of a Carbon Sink in the Oceans 被引量:1
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作者 MA Caihua YOU Kui +2 位作者 JI Dechun MA Weiwei LI Fengqi 《Journal of Ocean University of China》 SCIE CAS 2015年第2期284-292,共9页
As a consequence of global warming and rising sea levels, the oceans are becoming a matter of concern for more and more people because these changes will impact the growth of living organisms as well as people's livi... As a consequence of global warming and rising sea levels, the oceans are becoming a matter of concern for more and more people because these changes will impact the growth of living organisms as well as people's living standards. In particular, it is extremely important that the oceans absorb massive amounts of carbon dioxide. This paper takes a pragmatic approach to analyzing the oceans with respect to the causes of discontinuities in oceanic variables of carbon dioxide sinks. We report on an application of chemical, physical and biological methods to analyze the changes of carbon dioxide in oceans. Based on the relationships among the oceans, land, atmosphere and sediment with respect to carbon dioxide, the foundation of carbon dioxide in shell-building and ocean acidification, the changes in carbon dioxide in the oceans and their impact on climate change, and so on, a vital conclusion can be drawn from this study. Specifically, under the condition that the oceans are not disturbed by external forces, the oceans are a large carbon dioxide sink. The result can also be inferred by the formula: C=A-B and G=E+F when the marine ecosystem can keep a natural balance and the amount of carbon dioxide emission is limited within the calrying capacity of the oceans. 展开更多
关键词 biological ecosystems Carbon Dioxide sinks marine carrying capacity
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Top coal flows in an excavation disturbed zone of high section top coal caving of an extremely steep and thick seam 被引量:8
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作者 Miao Shengjun Lai Xingping Cui Feng 《Mining Science and Technology》 EI CAS 2011年第1期99-105,共7页
Compared with gentle dip long-wall caving,the length of a working face in fully-mechanized top-coal caving for extremely steep and thick seams is short,while its horizontal section is high with increasing production.B... Compared with gentle dip long-wall caving,the length of a working face in fully-mechanized top-coal caving for extremely steep and thick seams is short,while its horizontal section is high with increasing production.But the caving ratio is low,which might result in some disasters,such as roof falls,induced by local and large area collapse of the top coal in a working face and dangers induced by gas accumulation. After the development of cracks and weakening of the coal body,the tall,broken section of the top coal(a granular medium)of an extremely steep seam(over 60°)shows clear characteristics of nonlinear movement.We have thoroughly analyzed the geological environment and mining conditions of an excavation disturbed zone.Based on the results from a physical experiment of large-scale 3D modeling and coupling simulation of top coal-water-gas,we conclude that the weakened top coal can be regarded as a non-continuous medium.We used a particle flow code program to compare and analyze migration processes and the movements of a 30 m high section top coal over time before and after weakening of an extremely steep seam in the Weihuliang coal mine.The results of our simulation, experiment and monitoring show that pre-injection of water and pre-splitting blasting improve caving ability and symmetrical caving,relieve space for large area dynamic collapse of top coal,prolong migration time of noxious gases and release them from the mined out area and so achieve safety in mining. 展开更多
关键词 Top coal flowsExtremely steep and thick coal seamHigh section top coal caving (HSTCC)Particle flow
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