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Study on Key Techniques for Multi-scale Expression of Laneway Traverse Data in MGIS 被引量:5
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作者 ZHANG Hai-rong YU Jing-song-di LIU Wei 《Journal of China University of Mining and Technology》 EI 2007年第4期508-512,共5页
The multi-scale expression of enormously complicated laneway data requires differentiation of both contents and the way the contents are expressed. To accomplish multi-scale expression laneway data must support multi-... The multi-scale expression of enormously complicated laneway data requires differentiation of both contents and the way the contents are expressed. To accomplish multi-scale expression laneway data must support multi-scale transformation and have consistent topological relationships. Although the laneway data generated by traverse survey-ing is non-scale data it is still impossible to construct a multi-scale spatial database directly from it. In this paper an al-gorithm is presented to first calculate the laneway mid-line to support multi-scale transformation; then to express topo-logical relationships arising from the data structure; and,finally,a laneway spatial database is built and multi-scale ex-pression is achieved using components GIS-SuperMap Objects. The research result is of great significance for improv-ing the efficiency of laneway data storage and updating,for ensuring consistency of laneway data expression and for extending the potential value of a mine spatial database. 展开更多
关键词 multi-scale expression traverse data MGIS laneway mid-line
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Antarctic Traverses from Zhongshan Station to Dome-A and the Result Analysis for the GPS Points along the Expedition Route 被引量:1
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作者 WANG Qinghua E Dongchen CHEN Chunming 《Geo-Spatial Information Science》 2002年第1期31-36,共6页
Some GPS points were set up and occupied and reoccupied along the traverse route from Zhongshan Station to DomeA.The result analysis for the GPS data processed by GAMIT/GLOBK package was presented in this paper.It was... Some GPS points were set up and occupied and reoccupied along the traverse route from Zhongshan Station to DomeA.The result analysis for the GPS data processed by GAMIT/GLOBK package was presented in this paper.It was indicated that the ice along the traverse route flowed with an 825 m/a velocity to the northwest in the last three years,which was the direction of the edge of the ice sheet.The maximum horizontal flow velocity is about 100 m/a.Moreover,due to the ice flow,a 0.21 m/a sedimentation rate is achieved.Finally,a 15 m/a 2 horizontal acceleration is achieved from the GPS data of the three different stages. 展开更多
关键词 Antarctic inland ice_sheet traverse DOME_A GPS GAMIT/GLOBK ice flow
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Influence of magnetically constricted arc traverse speed (MCATS) on tensile properties and microstructural characteristics of welded Inconel 718 alloy sheets 被引量:1
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作者 Tushar Sonar Visvalingam Balasubramanian +2 位作者 Sudersanan Malarvizhi Thiruvenkatam Venkateswaran Dhenuvakonda Sivakumar 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第4期1395-1413,共19页
The magnetically constricted arc technique was implemented to mitigate the heat input related metallurgical problems in Gas Tungsten Arc Welding(GTAW)of Inconel 718 alloy particularly Nb segregation and subsequent lav... The magnetically constricted arc technique was implemented to mitigate the heat input related metallurgical problems in Gas Tungsten Arc Welding(GTAW)of Inconel 718 alloy particularly Nb segregation and subsequent laves phase evolution in fusion zone.This paper reports the direct effect of magnetically constricted arc traverse speed(MCATS)on bead profile,tensile properties and microstructural evolution of Inconel 718 alloy sheets joined by Gas Tungsten Constricted Arc Welding(GTCAW)process.The mechanism amenable for the microstructural modification and corresponding influence on the tensile properties of joints is investigated both in qualitative and quantitative manner related to the mechanics of arc constriction and pulsing.It is correlated to the solidification conditions during welding.The relationship between MCATS and Arc Constriction Current(ACC)was derived.Its interaction effect on the magnetic arc constriction and joint performance was analysed.Results showed that the joints fabricated using CATS of 70 mm/min exhibited superior tensile properties(98.39% of base metal strength with 31.50% elongation).It is attributed to the grain refinement in fusion zone microstructure leading to the evolution of finer,discrete laves phase in interdendritic areas. 展开更多
关键词 GTCA welding Inconel 718 alloy Magnetically constricted arc traverse speed Tensile properties Microstructure Laves phase
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Comprehensive Study on the Estimation of the Variance Components of Traverse Nets
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作者 WANG Zhongfeng 《Geo-Spatial Information Science》 2003年第1期43-48,共6页
This paper advances a new simplified formula for estimating variance components ,sums up the basic law to calculate the weights of observed values and a circulation method using the increaments of weights when estimat... This paper advances a new simplified formula for estimating variance components ,sums up the basic law to calculate the weights of observed values and a circulation method using the increaments of weights when estimating the variance components of traverse nets,advances the charicteristic roots method to estimate the variance components of traveres nets and presents a practical method to make two real and symmetric matrices two diagonal ones. 展开更多
关键词 traverse nets variance component redundant observation component law to calculate weights characteristic roots method
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EFFECTS OF S86019, AN ACTIVE COMPONENT FROM PURALIA LOB AT A, ON CELL DIFFERENTIATION AND CELL CYCLE TRAVERSE OF HL-60 CELLS
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作者 韩锐 焦鹭 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1990年第3期54-56,共3页
The effects of S86019, an active component from Puralia lobata, on the induction of cell differentiation and cell cycle traverse of HL-60 cells were described. It was shown that cell proliferation of HL-60 cells was i... The effects of S86019, an active component from Puralia lobata, on the induction of cell differentiation and cell cycle traverse of HL-60 cells were described. It was shown that cell proliferation of HL-60 cells was inhibited by S86019 in vitro. Under the action of S86019 the HL-60 cells were induced to differentiate into metamyelocytes, myelocytes and much matured cells with banded or segmented nucleus. Flow cytometry demonstrated that the cell population of HL-60 cells was blocked at G1 phase which resulted in the elevation of percentage of G1 cells and decrease of percentage of cells in S phase. Experimental results demonstrated that S86019 is an active inducer of cell differentiation in HL-60 cells. 展开更多
关键词 HL ON CELL DIFFERENTIATION AND CELL CYCLE traverse OF HL-60 CELLS EFFECTS OF S86019 AN ACTIVE COMPONENT FROM PURALIA LOB AT A
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Recent Russian remote sensing investigations in Antarctica within the framework of scientific traverses
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作者 Sergey V.Popov 《Advances in Polar Science》 2015年第2期113-121,共9页
This paper includes a short historical review of Russian and Soviet scientific traverses to study the Antarctic inland. The first traverse left on April 2, 1956. It resulted in the opening of the first Russian inland ... This paper includes a short historical review of Russian and Soviet scientific traverses to study the Antarctic inland. The first traverse left on April 2, 1956. It resulted in the opening of the first Russian inland research station named Pionerskaya and provided the first geophysical and glaciological data on regions inland of the Antarctic coast. By 1965, a number of regional inland scientific traverses had been completed and. the first Atlas of Antarctica was published in 1966. The atlas presented the main achievements of that time. After the discovery of Lake Vostok, Russian scientists commenced remote sensing investigations to study this unique natural phenomenon. The propagation of acoustic and electromagnetic waves in the glacier near Vostok Station were measured to provide important geophysical data. Radio-echo sounding data showed that Lake Vostok is isolated and separated from the rest of the Antarctic subglacial hydrosphere. The total area of the lake is 15 790 km2, excluding 365 km^2 occupied by 11 islands. Reflection seismic soundings of Lake Vostok estimated a total volume of about 6 100 km^3, an average depth of about 400 m, and a maximum depth of 1 200 m. Since 2008, there have been a number of scientific traverses between Mirny and Vostok stations and between Progress and Vostok stations. The data collected during the traverses have provided new insights into sub-ice topography and ice sheet structure, and have led to the discovery of subglacial lakes near Komsomolskaya Station and under Pionerskaya Station. 展开更多
关键词 Russian scientific traverses Lake Vostok ANTARCTICA remote sensing radio-echo sounding seismic
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Gravity Survey along the Mizuho Traverse Routes, East Antarctica: SEAL Seismic Exploration in 1999-2000
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作者 Shigeru Toda Hiroki Miyamachi +2 位作者 Hiroshi Murakami Tomoki Tsutsui Masaki Kanao 《International Journal of Geosciences》 2013年第10期1392-1400,共9页
A gravity survey was conducted along the Mizuho traverse routes in austral summer of 1999-2000 by the 41st Japanese Antarctic Research Expedition (JARE-41). The main purpose of the survey was to obtain detail gravity ... A gravity survey was conducted along the Mizuho traverse routes in austral summer of 1999-2000 by the 41st Japanese Antarctic Research Expedition (JARE-41). The main purpose of the survey was to obtain detail gravity anomaly along the traverse routes, where deep seismic exploration was simultaneously conducted in order to obtain a fine crustal structure of the Mizuho Plateau. By using SCINTREX (CG-3M) gravity meter, the survey was carried out at 160 sites with about 1 km interval in a distance of 190 km from S16 to Z20 on the traverse routes. Free-air and Bouguer anomalies were calculated using precise locations by GPS measurements, by taking into account an effect of the thick icesheet. The furrowed negative Free-air anomalies are identified around H192, where middle points of the whole traverse routes. Two bedrock elevation models derived both by seismic refraction analyses and radio-echo sounding might correspond to the bottom and the top of a mixture layer composed from ice-moraine rocks over the bedrock surface. Thickness of the crust estimated by Bouguer anomalies is 0.5 - 1 km larger toward inland at the terminal point of Z20 along the profile. 展开更多
关键词 GRAVITY Survey Mizuho traverse Routes BEDROCK ELEVATION Bouguer GRAVITY ANOMALY CRUSTAL Structure
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Record on History Traversed by Both Tibet And the Motherland──Speech at the Distribution Ceremony of Full-Length Pictorial 'Treasures'
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作者 NGAPOI NGAWANG JIGMEI 《China's Tibet》 1999年第3期3-6,共4页
关键词 Record on History traversed by Both Tibet And the Motherland Speech at the Distribution Ceremony of Full-Length Pictorial
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The Road Traversed by Lhumao
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作者 CHENG QIANG 《China's Tibet》 1996年第2期23-23,共1页
The Road Traversed by LhumaoTheRoadTraversedbyLhumao¥CHENGQIANGAtfirstsight,IfoundthatLhumaolookedexactlyass... The Road Traversed by LhumaoTheRoadTraversedbyLhumao¥CHENGQIANGAtfirstsight,IfoundthatLhumaolookedexactlyasshehadbeendescribe... 展开更多
关键词 The Road traversed by Lhumao
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Effects of traverse speed on weld formation,microstructure and mechanical properties of ZK60 Mg alloy joint by bobbin tool friction stir welding 被引量:4
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作者 Gaohui LI Li ZHOU +2 位作者 Haifeng ZHANG Sanfeng LUO Ning GUO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2021年第12期238-250,共13页
ZK60B(Mg-6%Zn-0.6%Zr)alloy joints fabricated by bobbin tool friction stir welding(BTFSW)with various traverse speeds were investigated.The sound joint fabricated by the BTFSW was possible under the appropriate welding... ZK60B(Mg-6%Zn-0.6%Zr)alloy joints fabricated by bobbin tool friction stir welding(BTFSW)with various traverse speeds were investigated.The sound joint fabricated by the BTFSW was possible under the appropriate welding parameters.The severe plastic deformation during BTFSW resulted in dispersion and segregation of the Zr-rich particles within the stirred zone(SZ)followed by evolution of a bimodal grain structure with distributed bands of 0.8-1.7μm ultrafine grains and 4.1-7.1μm equiaxed grains.Micro-hardness of SZ is substantially reduced in contrast to that of parent metal(PM)in spite of the finer grain size owing to dissolution of Mg-Zn based precipitates having hardening effects on alpha-Mg matrix.With the decrease in traverse speed,randomization degree of the plasticized metal flow increases,which is evidenced by the randomized arc line pattern at the low traverse speed.Among all defect-free joints,the 200 mm/min joint exhibits the weakest isotropy of texture within SZ and the best tensile properties,which has reduced ultimate tensile strength and yield strength by 5.4% and by 22.2%,respectively,as compared to the PM.The randomized texture hinders the joint fracturing within SZ at low elongation.Therefore,a relatively high elongation of 10.8% was achieved,which corresponded to 72% of the PM value. 展开更多
关键词 Bobbin tool Friction stir welding(FSW) Magnesium alloys Mechanical properties Microstructure evolution traverse speed
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REFLECTION OF OBLIQUE INCIDENT WAVES BY PERFORATED CAISSONS WITH TRAVERSE WALL 被引量:2
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作者 LIYu-cheng LIUHong-jie DONGGuo-hai 《Journal of Hydrodynamics》 SCIE EI CSCD 2005年第3期257-268,共12页
The interaction of oblique incident waves with infinite number of perforated caissons is investigated. The fluid domain is divided into infinite sub-domains by the caissons, and eigen-function expansion is applied to ... The interaction of oblique incident waves with infinite number of perforated caissons is investigated. The fluid domain is divided into infinite sub-domains by the caissons, and eigen-function expansion is applied to expand velocity potentials in each domain. A phase relation is introduced for wave oscillation in each caisson, and the structure geometry is considered in constructing the models of reflection waves. The reflected waves with the present analysis include all of the waves traveling in different directions when incident wave period is short. Numerical examinations show that velocities at the inner and outer sides of the front walls of caissons ase close to each other, and reflection coefficients satisfy the energy conservation relation very well when porous effect parameter is infinite. Numerical results show that the reflection coefficients of oblique incident waves are smaller for shorter caissons at low frequency, and decrease with the increase of wave incident angle. 展开更多
关键词 wave reflection oblique incident wave traverse wall perforated caisson eigen-function expansion
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Macroscopic Traversable Wormholes: Minimum Requirements
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作者 Peter K. F. Kuhfittig 《International Journal of Astronomy and Astrophysics》 2024年第3期230-243,共14页
While wormholes are just as good a prediction of Einstein’s theory as black holes, they are subject to severe restrictions from quantum field theory. To allow for the possibility of interstellar travel, a macroscopic... While wormholes are just as good a prediction of Einstein’s theory as black holes, they are subject to severe restrictions from quantum field theory. To allow for the possibility of interstellar travel, a macroscopic wormhole would need to maintain sufficiently low radial tidal forces. It is proposed in this paper that the assumption of zero tidal forces, i.e., the limiting case, is sufficient for overcoming the restrictions from quantum field theory. The feasibility of this approach is subsequently discussed by 1) introducing the additional conditions needed to ensure that the radial tidal forces can indeed be sufficiently low and 2) by viewing traversable wormholes as emergent phenomena, thereby increasing the likelihood of their existence. 展开更多
关键词 Morris-Thorne Wormholes Traversability Minimum Requirements STABILITY Compatibility with Quantum Field Theory
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Noncommutative-Geometry Wormholes Based on the Casimir Effect 被引量:1
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作者 Peter K. F. Kuhfittig 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第1期295-300,共6页
While wormholes are as good a prediction of Einstein’s theory as black holes, they are subject to severe restrictions from quantum field theory. In particular, holding a wormhole open requires a violation of the null... While wormholes are as good a prediction of Einstein’s theory as black holes, they are subject to severe restrictions from quantum field theory. In particular, holding a wormhole open requires a violation of the null energy condition, calling for the existence of exotic matter. The Casimir effect has shown that this physical requirement can be met on a small scale, thereby solving a key conceptual problem. The Casimir effect does not, however, guarantee that the small-scale violation is sufficient for supporting a macroscopic wormhole. The purpose of this paper is to connect the Casimir effect to noncommutative geometry, which also aims to accommodate small-scale effects, the difference being that these can now be viewed as intrinsic properties of spacetime. As a result, the noncommutative effects can be implemented by modifying only the energy momentum tensor in the Einstein field equations, while leaving the Einstein tensor unchanged. The wormhole can therefore be macroscopic in spite of the small Casimir effect. 展开更多
关键词 Traversable Wormholes Noncommutative Geometry Casimir Effect
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轿车尾流移测试验研究 被引量:1
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作者 张群锋 王望予 +1 位作者 傅立敏 蔡国华 《兵工学报》 EI CAS CSCD 北大核心 2000年第1期57-60,共4页
轿车的尾流结构与其空气阻力、升力与安全性有密切联系 ,为进一步研究轿车尾流结构及验证尾流场数值模拟结果的精确性提供依据 ,需通过试验得到较为全面地反映尾流结构的定量信息。为此 ,进行了红旗CA774轿车 1 10模型的七孔探针尾流移... 轿车的尾流结构与其空气阻力、升力与安全性有密切联系 ,为进一步研究轿车尾流结构及验证尾流场数值模拟结果的精确性提供依据 ,需通过试验得到较为全面地反映尾流结构的定量信息。为此 ,进行了红旗CA774轿车 1 10模型的七孔探针尾流移测试验 。 展开更多
关键词 尾流结构 尾流移测 七孔探针 A WAKE traverse SURVEY ON PASSENGER CARS Zhang Qunfeng Wang Wangyu FU Limin
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陀螺控制导线精度的正确评定 被引量:2
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作者 冯仲科 陈于恒 《有色金属》 CSCD 1992年第1期1-5,9,共6页
本文推证了陀螺控制导线精度评定的严密公式,并讨论了用误差椭圆来表示最弱点点位精度的方法。所有评定精度的公式均依据最小二乘矩阵平差原理得出,这些公式对正确进行误差预计很有意义。
关键词 EVALUATION Gyro-control traverse PRECISION Error ellipse
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Exploration of Traversable Wormholes Sustained by an Extra Spatial Dimension
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作者 Peter K. F. Kuhfittig 《International Journal of Astronomy and Astrophysics》 2023年第3期141-153,共13页
The main goal of this paper is to determine the effect of an extra dimension on a traversable wormhole. Here an earlier study by the author [Phys. Rev. D 98, 064041 (2018)] is extended in several significant ways. To ... The main goal of this paper is to determine the effect of an extra dimension on a traversable wormhole. Here an earlier study by the author [Phys. Rev. D 98, 064041 (2018)] is extended in several significant ways. To begin with, the extra spatial dimension is assumed to be time dependent, while the redshift and shape functions, as well as the extra dimension, are functions of both r and l, the respective radial and extra coordinates;the last of these is therefore a function of r, l, and t. The main objective is to determine the conditions that allow the throat of the wormhole to be threaded with ordinary matter (by respecting the null energy condition) and that the same conditions lead to a violation of the null energy condition in the fifth dimension, which is therefore responsible for sustaining the wormhole. The dependence of the extra dimension on l and t is subject to additional conditions that are subsequently analyzed in this paper. Finally, the extra dimension may be extremely small or even curled up. 展开更多
关键词 Traversable Wormholes Extra Spatial Dimension Time Dependence
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CASIO fx-4500P计算器在建筑工程测量中的应用(下)
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作者 莫南明 《旅游研究》 1997年第1期53-58,68,共7页
9.1 计算导线转折角和 计算器全清零后,找到文件名“GZJH”,进行如下操作:
关键词 Computer APPLICATION TRIANGULATION Chain Of APPLICATION Adjustment Adjustment of traverse Calculating PROGRAMME
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Optimization of RDF link traversal based query execution 被引量:2
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作者 朱艳琴 花岭 《Journal of Southeast University(English Edition)》 EI CAS 2013年第1期27-32,共6页
Aiming at the problem that only some types of SPARQL ( simple protocal and resource description framework query language) queries can be answered by using the current resource description framework link traversal ba... Aiming at the problem that only some types of SPARQL ( simple protocal and resource description framework query language) queries can be answered by using the current resource description framework link traversal based query execution (RDF-LTE) approach, this paper discusses how the execution order of the triple pattern affects the query results and cost based on concrete SPARQL queries, and analyzes two properties of the web of linked data, missing backward links and missing contingency solution. Then three heuristic principles for logic query plan optimization, namely, the filtered basic graph pattern (FBGP) principle, the triple pattern chain principle and the seed URIs principle, are proposed. The three principles contribute to decrease the intermediate solutions and increase the types of queries that can be answered. The effectiveness and feasibility of the proposed approach is evaluated. The experimental results show that more query results can be returned with less cost, thus enabling users to develop the full potential of the web of linked data. 展开更多
关键词 web of linked data resource description framework link traversal based query execution (RDF-LTE) SPARQL query query optimization
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Science and exploration in the high interior of East Antarctica in the twentieth century 被引量:1
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作者 Irina Gan David Drewry +1 位作者 Ian Allison Vladimir Kotlyakov 《Advances in Polar Science》 2016年第2期65-77,共13页
The highest part of the East Antarctic Ice Sheet, more than 4000 m above sea level, has been an area that has seen a considerable scientific research effort undertaken by the Chinese National Antarctic Research Expedi... The highest part of the East Antarctic Ice Sheet, more than 4000 m above sea level, has been an area that has seen a considerable scientific research effort undertaken by the Chinese National Antarctic Research Expedition, and its international collaborators, since January 2005. That includes the establishment of the most remote Of the Chinese Antarctic stations, Kunlun, at Dome A in 2009. However, the exploration and mapping of this region had been commenced many decades earlier, most notably by inland traverses of the Union of Soviet Socialist Republics during the 1957-1958 International Geophysical Year 0GY) and later; and the extensive surveys of Antarctic surface and sub-ice topography by airborne radio-echo sounding made by the US National Science Foundation-Scott Polar Research Institute-Technical University of Denmark (NSF-SPRI-TUD) in the late-1960s and the 1970s. Here we provide a history of the activities and achievements of these earlier programs. Recent topographic maps of the ice sheet surface in the Dome A region, produced using Chinese GPS data and satellite altimetry, have shown the maps compiled from the earlier data were remarkably accurate. 展开更多
关键词 East Antarctica Dome A Gamburtsev Mountains traverse sub-glacial mapping seismic radio-echosounding (RES)
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Application of Electrical Resistivity Imaging in Investigating Groundwater Pollution in Sapele Area, Nigeria 被引量:1
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作者 Okezie Uchegbulam Elijah A. Ayolabi 《Journal of Water Resource and Protection》 2014年第14期1369-1379,共11页
Sixty-four multi-electrode Lund imaging system coupled with ABEM SAS 4000 Terrameter was used for the electrical imaging of the study area. Wenner and Gradient arrays with 2 m minimum electrode spacing were employed w... Sixty-four multi-electrode Lund imaging system coupled with ABEM SAS 4000 Terrameter was used for the electrical imaging of the study area. Wenner and Gradient arrays with 2 m minimum electrode spacing were employed which revealed resistivity changes in the vertical and horizontal directions along the survey lines. Earth imager software was employed for?the processing and the iteration of the 2-D resistivity data. The subsurface is characterized with soil material with resistivity ranging from 42 - 15,000 Ohm-m, reflective of varying degree of conductivity associated with changing lithology and fluid type. Correlation with borehole data shows that the first 10 m is composed of laterite. While sand materials occupy 10 to about 60 m beneath the surface, with anomalously high resistivity ≤15,000 Ohm-m in most parts. These high resistivity formations can be attributed to the presence of hydrocarbon within the subsurface, which is an indication that shallow aquifer in the study area has been polluted. The water level in the study area is close to the surface, between 4 - 5 m. As a result of the high resistivity formations in most parts, deep wells of about 45 m are recommended after geophysical investigations. 展开更多
关键词 Electrical RESISTIVITY IMAGING POLLUTION traverse LINES
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