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Spatial structural characteristics of the Deda ancient landslide in the eastern Tibetan Plateau:Insights from Audio-frequency Magnetotellurics and the Microtremor Survey Method
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作者 Zhen-dong Qiu Chang-bao Guo +5 位作者 Yi-ying Zhang Zhi-hua Yang Rui-an Wu Yi-qiu Yan Wen-kai Chen Feng Jin 《China Geology》 CAS CSCD 2024年第2期188-202,共15页
It is of crucial importance to investigate the spatial structures of ancient landslides in the eastern Tibetan Plateau’s alpine canyons as they could provide valuable insights into the evolutionary history of the lan... It is of crucial importance to investigate the spatial structures of ancient landslides in the eastern Tibetan Plateau’s alpine canyons as they could provide valuable insights into the evolutionary history of the landslides and indicate the potential for future reactivation.This study examines the Deda ancient landslide,situated in the Chalong-ranbu fault zone,where creep deformation suggests a complex underground structure.By integrating remote sensing,field surveys,Audio-frequency Magnetotellurics(AMT),and Microtremor Survey Method(MSM)techniques,along with engineering geological drilling for validation,to uncover the landslide’s spatial feature s.The research indicates that a fault is developed in the upper part of the Deda ancient landslide,and the gully divides it into Deda landslide accumulation zoneⅠand Deda landslide accumulation zoneⅡin space.The distinctive geological characteristics detectable by MSM in the shallow subsurface and by AMT in deeper layers.The findings include the identification of two sliding zones in the Deda I landslide,the shallow sliding zone(DD-I-S1)depth is approximately 20 m,and the deep sliding zone(DD-I-S2)depth is 36.2-49.9 m.The sliding zone(DD-Ⅱ-S1)depth of the DedaⅡlandslide is 37.6-43.1 m.A novel MSM-based method for sliding zone identification is proposed,achieving less than 5%discrepancy in depth determination when compared with drilling data.These results provide a valuable reference for the spatial structural analysis of large-deepseated landslides in geologically complex regions like the eastern Tibetan Plateau. 展开更多
关键词 Ancient landslide Remote sensing Audio-frequency Magnetotellurics(AMT) Microtremor survey method(MSM) Geological drilling engineering Spatial structure Tibetan Plateau Geological hazard survey engineering
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Research on the Testing Methods of Instrumental System in the Marine Magnetic Survey 被引量:1
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作者 边刚 刘雁春 +2 位作者 于波 肖付民 卞光浪 《Marine Science Bulletin》 CAS 2007年第2期1-11,共11页
Testing methods of instrumental system in the marine magnetic survey have been studied in this paper, and the feasibility of each method has been testified by the observed data. The conclusion shows that the method br... Testing methods of instrumental system in the marine magnetic survey have been studied in this paper, and the feasibility of each method has been testified by the observed data. The conclusion shows that the method brought out can effectively eliminate the systematic error caused by the instrumental system, and greatly improve the surveying precision and the reliability of the survey results. 展开更多
关键词 Marine magnetic survey instrumental system testing method
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Application of passive source surface-wave method in site engineering seismic survey 被引量:2
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作者 Chaofan Wang Jian Zhang +2 位作者 Lihui Yan Hui Liu Dong Zhao 《Earthquake Science》 2014年第1期101-106,共6页
Site engineering seismic survey provides basic data for seismic effect analysis. As an important parameter of soil, shear-wave velocity is usually obtained through wave velocity testing in borehole. In this paper, the... Site engineering seismic survey provides basic data for seismic effect analysis. As an important parameter of soil, shear-wave velocity is usually obtained through wave velocity testing in borehole. In this paper, the passive source surface-wave method is introduced into the site engineering seismic survey and practically applied in an engineering site of Shijingshan District. By recording the ubiquitous weak vibration on the earth surface, extract the dispersion curve from the surface-wave components using the SPAC method and obtain the shear-wave velocity structure from inversion. Over the depth of 42 m under- ground, it totally consists of five layers with interface depth of 3.31, 4.50, 7.23, 17.41, and 42.00 m; and shear-wave velocity of 144.0, 198.3, 339.4, 744.2, and 903.7 m/s, respectively. The inversion result is used to evaluate site classification, determine the maximum shear modulus of soil, provide basis for further seismic hazard analysis and site assessment or site zoning, etc. The result shows that the passive source surface-wave method is feasible in the site engineering seismic survey and can replace boreholes,shorten survey period, and reduce engineering cost to some extent. 展开更多
关键词 Passive source surface-wave method Shearwave velocity Dispersion curve Seismic effect Engineering seismic survey
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A method of measuring the [α/Fe] ratios from the spectra of the LAMOST survey 被引量:1
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作者 Ji Li Chen Han +13 位作者 Mao-Sheng Xiang Jian-Rong Shi Jing-Kun Zhao Xiao-Wei Liu Hua-Wei Zhang Hai-Bo Yuan Xuan Ci Xiao-Feng Zhang Yue-Xiang Wang Yang Huang Yong Zhang Yong-Hui Hou Yue-Fei Wang Zi-Huang Cao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第7期83-96,共14页
The [α/Fe] ratios in stars are good tracers to probe the formation history of stellar populations and the chemical evolution of the Galaxy. The spectroscopic survey of LAMOST provides a good opportunity to determine ... The [α/Fe] ratios in stars are good tracers to probe the formation history of stellar populations and the chemical evolution of the Galaxy. The spectroscopic survey of LAMOST provides a good opportunity to determine [α/Fe] of millions of stars in the Galaxy. We present a method of measuring the [α/Fe]ratios from LAMOST spectra using the template-matching technique of the LSP3 pipeline. We use three test samples of stars selected from the ELODIE and MILES libraries, as well as the LEGUE survey to validate our method. Based on the test results, we conclude that our method is valid for measuring [α/Fe]from low-resolution spectra acquired by the LAMOST survey. Within the range of the stellar parameters Teff= [5000, 7500] K, log g = [1.0, 5.0] dex and [Fe/H]= [onsistent with values derived from high-resolution spectra,-1.5, +0.5] dex, our [α/Fe] measurements are c and the accuracy of our [α/Fe] measurements from LAMOST spectra is better than 0.1 dex with spectral signal-to-noise higher than 20. 展开更多
关键词 GALAXY evolution stars abundances stars fundamental parameters techniques spectroscopy surveys methods data analysis
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Are the altitudinal patterns of plant diversity derived from field surveys consistent with those from empirical integrated methods?
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作者 ZHAN Qing-hua FU Zhi-hao +2 位作者 ZHOU Ya-dong YAN Xue WANG Qing-feng 《Journal of Mountain Science》 SCIE CSCD 2023年第5期1307-1315,共9页
Field surveys and empirical integrated methods are commonly used in the ecological research to understand the altitudinal pattern of plant diversity of mountains.However,few studies have compared the differences betwe... Field surveys and empirical integrated methods are commonly used in the ecological research to understand the altitudinal pattern of plant diversity of mountains.However,few studies have compared the differences between the two methods on the same scale.Here,we addressed and compared the altitudinal patterns of species richness(SR),phylogenetic diversity(PD),the standardized effect size of phylogenetic diversity(PDses)and mean phylogenetic distance(MPDses)of about 580 angiosperms growing on Mount Kenya from two independent datasets:one is based on our several times field surveys in this mountain and another one is based on empirical data integrated from literatures.We found that the altitudinal diversity patterns of field surveys dataset were consistent with the empirical integrated dataset.Both SR and PD showed hump-shaped patterns along the altitude,and both PDses and MPDses showed monotonically decreasing patterns along the altitude.The ratio of diversity between field surveys dataset and empirical integrated dataset were gradually increase along the altitude.Our research provides new insight for understanding the altitudinal diversity patterns of plants of a tropical mountain. 展开更多
关键词 Mount Kenya AFRICA surveys Interpolation method TAXONOMIC PHYLOGENETIC
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A NEW METHOD FOR INCREASING PRECISION IN SURVEY SAMPLING
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作者 冯士雍 邹国华 《Acta Mathematica Scientia》 SCIE CSCD 2001年第2期282-288,共7页
This paper proposes a new method for increasing the precision in survey sam- pling, i.e., a method combining sampling with prediction. The two cases where auxiliary information is or not available are considered. A nu... This paper proposes a new method for increasing the precision in survey sam- pling, i.e., a method combining sampling with prediction. The two cases where auxiliary information is or not available are considered. A numerical example is given. 展开更多
关键词 survey sampling prediction method simple random sampling
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Methods for Setting up a Three-Dimensional Industrial Surveying System of “Building Blocks Type”
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作者 FENGWenhao 《Geo-Spatial Information Science》 2004年第3期157-161,共5页
This paper is to advance some relevant techniques to set up a three-dimensional industrial surveying system of “building blocks type”, making use of the electronic theodolite, standard ruler and portable computer.
关键词 three-dimensional industrial surveying system initial direction innertarget collimator method standard ruler accuracy
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Problems and Recommendations for Rural Statistics and Survey Methods
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作者 Chengjun ZHANG 《Asian Agricultural Research》 2014年第8期5-7,共3页
With constant deepening of the reform and opening-up,national economic system has changed from planned economy to market economy,and rural survey and statistics remain in a difficult transition period. In this period,... With constant deepening of the reform and opening-up,national economic system has changed from planned economy to market economy,and rural survey and statistics remain in a difficult transition period. In this period,China needs transforming original statistical mode according to market economic system. All levels of government should report and submit a lot and increasing statistical information. Besides,in this period,townships,villages and counties are faced with old and new conflicts. These conflicts perplex implementation of rural statistics and survey and development of rural statistical undertaking,and also cause researches and thinking of reform of rural statistical and survey methods. 展开更多
关键词 RURAL areas STATISTICS survey methodS PROBLEMS and
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Application of Sampling Methods to Geological Survey
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《Journal of Earth Science》 SCIE CAS CSCD 2000年第2期103-104,共2页
关键词 WORK Application of Sampling methods to Geological survey
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Agile Software Development Methodologies: Survey of Surveys
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作者 Malek Al-Zewairi Mariam Biltawi +1 位作者 Wael Etaiwi Adnan Shaout 《Journal of Computer and Communications》 2017年第5期74-97,共24页
Agile software design and development methodologies have been gaining rigorous attention in the software engineering research community since their early introduction in the mid-nineties in addition to being highly ad... Agile software design and development methodologies have been gaining rigorous attention in the software engineering research community since their early introduction in the mid-nineties in addition to being highly adopted by the software development industry. In the last 15 years, an excessive number of research studies have been conducted on agile methods, a great number of notable methods have been proposed and various surveys have been presented by many researchers. In this study, the authors intend to conduct a literature survey study of the surveys of the different agile methodologies ranging from January 2000 to December 2015 using an intuitive research methodology called “Compare and Review” (CR). Furthermore, these survey papers were classified into four major categories according to their area of study. Additionally, the newly proposed agile methodologies that have not been addressed yet in any other literature review were reviewed and compared in terms of where the changes that they proposed lay on the SDLC. 展开更多
关键词 AGILE Software methods survey COMPARE and REVIEW Research methodOLOGY
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Assessment of Domestic Water Sources Safety: Application of the Micro Biological Survey Method and Microbiological Profile of the Contaminating Bacteria
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作者 Sali Ben Béchir Adogaye Mabvouna Biguioh Rodrigue +5 位作者 Nkamedjie Pete Patrick Martial Andrillene Laure Deutou Wondeu Sanou Sobze Martin Jean Blaise Kemogne Carla Montesano Colizzi Vittorio 《Journal of Water Resource and Protection》 2021年第5期350-361,共12页
Water is essential for human life and it’s expected to be clean and safe. In Cameroon, government efforts to improve access to drinking water are mitigated. Many households are suffering from chronic water shortages ... Water is essential for human life and it’s expected to be clean and safe. In Cameroon, government efforts to improve access to drinking water are mitigated. Many households are suffering from chronic water shortages leading to the majority of people using doubtful water sources. This study was carried out in accordance with guidelines produced by the STARBIOS2-EU funded project on Responsible Research and Innovation and aimed to assess the microbiological quality of water samples collected from domestic water sources in 3 divisions of the West region of Cameroon. 22 water samples from well water, stream, water pump and river were aseptically collected. At each sampling point, 50 mL of sample was taken aseptically and immediately transported to the laboratory for analysis. The detection of Coliforms bacteria was done using Micro Biological Survey (MBS) method. 1 mL of each sample was inoculated in the Coliforms MBS (Coli MBS) vial initially rehydrated with 10 mL of sterile distilled water. The Coli MBS vials were closed, shaken for homogenization, and then incubated at 37<span style="white-space:nowrap;">&deg;</span>C. From the initial red color of the Coli MBS vials, changes in color to yellow of the reaction vials were monitored at three different time intervals (12 h, 19 h and 24 h), corresponding to three levels of bacterial concentration. All positives samples on MBS method were selected to determine the presence of <em>E. coli</em> Loop full broths of Coli MBS vials were taken;streaked into the eosin methylene blue (EMB) agar plate and incubated at 37°C for 24 hours. <em>E. coli</em> was confirmed by observing green metallic sheen on EMB agar plate. The biochemical indole, methyl red, Voges-Proskauer and citrate (IMViC) test was performed to determine the complete microbiological profile of the water samples. Almost all the water samples were contaminated with Total Coliforms (TC). A high concentration of TC (>10<sup>3</sup> CFU/mL) was found in 8 samples (36.4%), a medium concentration (10 < x < 10<sup>3</sup> CFU/mL) was observed in 10 samples (45.5%) and 2 samples (9.1%) were low concentrated (1 < x < 10 CFU/mL). 8 samples were positive for the presence of <em>E. coli</em> by observing the green metallic sheen on EMB agar plates. The IMViC test confirmed the presences of 5 bacteria species: <em>Enterobacter spp., Klebsiella spp., E. coli spp., Salmonella spp.</em> and Shigella spp. We recommend integrating sanitary assessment in the design and implementation of water supply projects. Regular water purification using proper methods and maintenances of the water point. Regular microbiological quality assessment of water intended for human consumption should be planned and carried out. 展开更多
关键词 Water Assessment Micro Biological survey method Biochemical IMViC Test West Cameroon
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Risk assessment of coastal flooding disaster by storm surge based on Elevation-Area method and hydrodynamic models:Taking Bohai Bay as an example
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作者 Fu Wang Xue-zheng Liu +3 位作者 Yong Li Heng Yu Ming-zheng Wen Yun-zhuang Hu 《China Geology》 CAS CSCD 2024年第3期494-504,共11页
The future inundation by storm surge on coastal areas are currently ill-defined.With increasing global sealevel due to climate change,the coastal flooding by storm surge is more and more frequently,especially in coast... The future inundation by storm surge on coastal areas are currently ill-defined.With increasing global sealevel due to climate change,the coastal flooding by storm surge is more and more frequently,especially in coastal lowland with land subsidence.Therefore,the risk assessment of such inundation for these areas is of great significance for the sustainable socio-economic development.In this paper,the authors use Elevation-Area method and Regional Ocean Model System(ROMS)model to assess the risk of the inundation of Bohai Bay by storm surge.The simulation results of Elevation-Area method show that either a 50-year or 100-year storm surge can inundate coastal areas exceeding 8000 km^(2);the numerical simulation results based on hydrodynamics,considering ground friction and duration of the storm surge high water,show that a 50-year or 100-year storm surge can only inundate an area of over 2000 km^(2),which is far less than 8000 km^(2);while,when taking into account the land subsidence and sea level rise,the very inundation range will rapidly increase by 2050 and 2100.The storm surge will greatly impact the coastal area within about 10-30 km of the Bohai Bay,in where almost all major coastal projects are located.The prompt response to flood disaster due to storm surge is urgently needed,for which five suggestions have been proposed based on the geological background of Bohai Bay.This study may offer insight into the development of the response and adaptive plans for flooding disasters caused by storm surge. 展开更多
关键词 Storm surge ROMS Elevation-Area method Numerical simulation Land subsidence Flooding disaster Sea level rise Marine geological survey engineering Geological disaster survey engineering Bohai Bay
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Application of geophysical methods in fine detection of urban concealed karst:A case study of Wuhan City,China
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作者 Dao-han Liu Lei Wang +3 位作者 Lei Liu Jun-jie Xu Jian-qiang Wu Pan Liu 《China Geology》 CAS CSCD 2024年第3期517-532,共16页
The construction of modern livable cities faces challenges in karst areas,including ground collapse and engineering problems.Wuhan,with a population of 13.74×10^(6) and approximately 1161 km^(2)of soluble rocks i... The construction of modern livable cities faces challenges in karst areas,including ground collapse and engineering problems.Wuhan,with a population of 13.74×10^(6) and approximately 1161 km^(2)of soluble rocks in the urban area of 8569.15 km^(2),predominantly consists of concealed karst areas where occasional ground collapse events occur,posing significant threats to underground engineering projects.To address these challenges,a comprehensive geological survey was conducted in Wuhan,focusing on major karstrelated issues.Geophysical methods offer advantages over drilling in detecting concealed karst areas due to their efficiency,non-destructiveness,and flexibility.This paper reviewed the karst geological characteristics in Wuhan and the geophysical exploration methods for karst,selected eight effective geophysical methods for field experimentation,evaluated their suitability,and proposed method combinations for different karst scenarios.The results show that different geophysical methods have varying applicability for karst detection in Wuhan,and combining multiple methods enhances detection effectiveness.The specific recommendations for method combinations provided in this study serve as a valuable reference for karst detection in Wuhan. 展开更多
关键词 Ground Penetrating Radar(GPR) Electric Resistivity Tomography(ERT) Opposing-coils Transient Electromagnetic method(OCTEM) Microtremor Array Measurements(MAM) Multi-channel Analysis of surface wave(MASW) Multi-source surface wave exploration(MSSW) Electromagnetic wave CT(EM CT) Surface Nuclear Magnetic Resonance(SNMR) Concealed karst Urban geological survey engineering
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Study on the applicability of frequency spectrum of micro-tremor and dynamic characteristics of surface ground in Asia area 被引量:5
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作者 CHE Ai-lan IWATATE Takahiro +1 位作者 ODA Yoshiya GE Xiu-run 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第11期1856-1863,共8页
The dynamic characteristics of ground soil using micro-tremor observation in Asia (Zushi and Ogasawara (Japan), Xi’an (China), Manila (Philippines), and Gujarat (India)) are studied. Ground micro-tremor signals were ... The dynamic characteristics of ground soil using micro-tremor observation in Asia (Zushi and Ogasawara (Japan), Xi’an (China), Manila (Philippines), and Gujarat (India)) are studied. Ground micro-tremor signals were observed and analyzed by fast Fourier transform method (FFT). The response of ground soil to frequency of ground micro-tremor is revealed, and func- tions with frequency-dependence and frequency-selection of micro-tremor for different foundation soil strata are also researched. The horizontal to vertical spectral ratio (H/V, Nakamura technique) of micro-tremor observed at the surface ground was used to evaluate the site’s predominant period. This paper also discusses the application of micro-tremor on site safety evaluation, and gives the observed calculation results obtained at multiple points. The experimental foundation and the deduction process of the method are described in detail. Some problems of the method are pointed out. Potential use of the technique’s good expandable nature makes it a useable means for preventing and reducing disaster’s harmful effects. 展开更多
关键词 micro-tremor observation Nakamura method Predominant period Earthquake observation Spectral analysis
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Mapping the Milky Way with LAMOSTⅠ:method and overview 被引量:5
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作者 Chao Liu Yan Xu +8 位作者 Jun-Chen Wan Hai-Feng Wang Jeffrey L.Carlin Li-Cai Deng Heidi Jo Newberg Zi-Huang Cao Yong-Hui Hou Yue-Fei Wang Yong Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第9期81-100,共20页
We present a statistical method to derive the stellar density profiles of the Milky Way from spectroscopic survey data, taking into account selection effects. We assume the selection function, which can be altered dur... We present a statistical method to derive the stellar density profiles of the Milky Way from spectroscopic survey data, taking into account selection effects. We assume the selection function, which can be altered during observations and data reductions, of the spectroscopic survey is based on photometric colors and magnitude. Then the underlying selection function for a line-of-sight can be recovered well by comparing the distribution of the spectroscopic stars in a color-magnitude plane with that of the photometric dataset. Subsequently, the stellar density profile along a line-of-sight can be derived from the spectroscopically measured stellar density profile multiplied by the selection function. The method is validated using Galaxia mock data with two different selection functions. We demonstrate that the derived stellar density profiles reconstruct the true ones well not only for the full set of targets, but also for sub-populations selected from the full dataset. Finally, the method is applied to map the density pro- files for the Galactic disk and halo, using the LAMOST RGB stars. The Galactic disk extends to about R = 19 kpc, where the disk still contributes about 10% to the total stellar surface density. Beyond this radius, the disk smoothly transitions to the halo without any truncation, bending or breaking. Moreover, no over-density corresponding to the Monoceros ring is found in the Galactic anti-center direction. The disk shows moderate north-south asymmetry at radii larger than 12 kpc. On the other hand, the R-Z tomographic map directly shows that the stellar halo is substantially oblate within a Galactocentric radius of 20 kpc and gradually becomes nearly spherical beyond 30 kpc. 展开更多
关键词 methods: statistical -- Galaxy structure -- Galaxy disk - Galaxy halo - surveys LAMOST
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Influence of Atmospheric Refraction on Horizontal Angle Surveying 被引量:3
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作者 ZHANG Zhenglu DENG Yong LUO Changlin MEI Wensheng 《Geo-Spatial Information Science》 2006年第3期157-161,共5页
Side-refraction is the main error source of horizontal angle surveying, but it has little influence on the sides by analyzing the influence of atmospheric-infraction on the ultrahigh-precision side and angle surveying... Side-refraction is the main error source of horizontal angle surveying, but it has little influence on the sides by analyzing the influence of atmospheric-infraction on the ultrahigh-precision side and angle surveying. Choosing oriented direction is crucial to distance and angle measurement in triangulateration network. How to select the oriented direction during angle measurement is presented, and the means to check the quality of auto-surveying with Georobot is brought forward as well. At last some solutions to reduce the influence of side-refraction while disposing and surveying ultrahigh-precision triangulateration network are put forward. 展开更多
关键词 atmospheric refraction horizontal angle surveying GEOROBOT interchanging method optimal oriented direction
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A Literature Review of Wind Forecasting Methods 被引量:7
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作者 Wen-Yeau Chang 《Journal of Power and Energy Engineering》 2014年第4期161-168,共8页
In this paper, an overview of new and current developments in wind forecasting is given where the focus lies upon principles and practical implementations. High penetration of wind power in the electricity system prov... In this paper, an overview of new and current developments in wind forecasting is given where the focus lies upon principles and practical implementations. High penetration of wind power in the electricity system provides many challenges to the power system operators, mainly due to the unpredictability and variability of wind power generation. Although wind energy may not be dispatched, an accurate forecasting method of wind speed and power generation can help the power system operators reduce the risk of unreliability of electricity supply. This paper gives a literature survey on the categories and major methods of wind forecasting. Based on the assessment of wind speed and power forecasting methods, the future development direction of wind forecasting is proposed. 展开更多
关键词 LITERATURE survey WIND Forecasting CATEGORIES WIND SPEED and Power Forecasting methodS
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Test area of the SAGE survey 被引量:2
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作者 Jie Zheng Gang Zhao +4 位作者 Wei Wang Zhou Fan Ke-Feng Tan Chun Li Fang Zuo 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第1期29-34,共6页
Sky surveys represent one of the most important efforts to improve developments in astrophysics,especially when using new photometric bands. We are performing the Stellar Abundance and Galactic Evolution(SAGE) survey ... Sky surveys represent one of the most important efforts to improve developments in astrophysics,especially when using new photometric bands. We are performing the Stellar Abundance and Galactic Evolution(SAGE) survey with a self-designed SAGE photometric system, which is composed of eight photometric bands. The project mainly aims to study the stellar atmospheric parameters of ~0.5 billion stars in ~12 000 deg2 of the northern sky, which mainly focuses on Galactic astronomy, as well as some aspects of extragalactic astronomy. This work introduces the detailed data reduction process of the test field NGC 6791, including the data reduction of single-exposure images and stacked multi-exposure images, and properties of the final catalog. 展开更多
关键词 methods:observational techniques:photometric surveys ASTROMETRY catalogs
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A Survey of Steel Arch Bridges in China 被引量:4
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作者 Baochun Chen Kangming Chen +1 位作者 Shozo Nakamura Qiu Zhao 《Journal of Civil Engineering and Architecture》 2011年第9期799-808,共10页
A review of the current status and progress of steel arch bridges in China is presented in this paper. The existing steel arch bridges in China were analyzed in terms of steel material, span, structure type, main arch... A review of the current status and progress of steel arch bridges in China is presented in this paper. The existing steel arch bridges in China were analyzed in terms of steel material, span, structure type, main arch rib form and construction method. The comparison with CFST arch bridges and RC arch bridges is also conducted. It is shown that steel arch bridge has gain rapid development in China since 2000, characterized by long main spans. As for the span, most of the steel arch bridges have a span less than 250 m, while when the span exceeds 350 m, steel arch bridges are strongly competitive against CFST or RC arch bridges. Over 80% of the bridges are through and half-through bridge types, and the arch ribs are hingeless structures. The rise-to-span ratios of the arches are mainly between 1:4 and 1: 5. Most of the arches use solid box ribs, and a small portion of arches use truss ribs in which box sections are mostly adopted for the truss members. The cantilever method and scaffolding method are the two main construction methods used, but some other construction methods have also been developed. 展开更多
关键词 Steel arch bridge survey bridge type RIB construction method China
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The SAGE photometric survey: technical description 被引量:1
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作者 Jie Zheng Gang Zhao +4 位作者 Wei Wang Zhou Fan Ke-Feng Tan Chun Li Fang Zuo 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第12期29-42,共14页
To investigate a huge sample of data related to the Stellar Abundance and Galactic Evolution(SAGE) survey in more detail, we are performing a northern sky photometric survey named SAGES with the SAGE photometric syste... To investigate a huge sample of data related to the Stellar Abundance and Galactic Evolution(SAGE) survey in more detail, we are performing a northern sky photometric survey named SAGES with the SAGE photometric system.This system consists of eight filters: Str?mgren-u, SAGE-v, SDSS g, r, i, DDO-51, Hαwideand Hαnarrow, including three Sloan broadband filters, three intermediateband filters, two narrow-band filters and one newly-designed narrow-band filter.SAGES covers~12 000 square degrees of the northern sky with δ >-5°, excluding the Galactic disk(|b| < 10°) and the sky area 12 h <RA <18 h.The photometric detection limit depth at signal-to-noise ratio 5σ can be as deep as V~20 mag.SAGES will produce a photometric catalog with uniform depth for~500 million stars with atmospheric parameters including effective temperature Teff, surface gravity log g and metallicity[Fe/H], as well as interstellar extinction to each individual target.In this work, we will briefly introduce the SAGE photometric system, the SAGE survey and a preliminary test field of the open cluster NGC 6791 and its surroundings. 展开更多
关键词 methods:observational techniques:photometric surveys ASTROMETRY catalogs
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