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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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Basic Survey Scheduling for the Wide Field Survey Telescope(WFST)
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作者 Yan-Peng Chen Ji-An Jiang +5 位作者 Wen-Tao Luo Xian-Zhong Zheng Min Fang Chao Yang Yuan-Yu Hong Zong-Fei Lü 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期59-69,共11页
Aiming at improving the survey efficiency of the Wide Field Survey Telescope, we have developed a basic scheduling strategy that takes into account the telescope characteristics, observing conditions, and weather cond... Aiming at improving the survey efficiency of the Wide Field Survey Telescope, we have developed a basic scheduling strategy that takes into account the telescope characteristics, observing conditions, and weather conditions at the Lenghu site. The sky area is divided into rectangular regions, referred to as “tiles,” with a size of2°. 577 × 2°. 634 slightly smaller than the focal area of the mosaic CCDs. These tiles are continuously filled in annulars parallel to the equator. The brightness of the sky background, which varies with the moon phase and distance from the moon, plays a significant role in determining the accessible survey fields. Approximately 50connected tiles are grouped into one block for observation. To optimize the survey schedule, we perform simulations by taking into account the length of exposures, data readout, telescope slewing, and all relevant observing conditions. We utilize the Greedy Algorithm for scheduling optimization. Additionally, we propose a dedicated dithering pattern to cover the gaps between CCDs and the four corners of the mosaic CCD array, which are located outside of the 3° field of view. This dithering pattern helps to achieve relatively uniform exposure maps for the final survey outputs. 展开更多
关键词 telescopes surveys MOON
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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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Enhancing landslide hazards survey and management to reduce the loss of human lives and properties
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作者 Yong-shuang Zhang 《China Geology》 CAS CSCD 2024年第2期169-170,共2页
Landslides are pervasive geohazards that pose a serious threat to human lives,property,and crucial engineering constructions.Annually,landslides lead to tens of thousands of fatalities(see the paper of"List of ty... Landslides are pervasive geohazards that pose a serious threat to human lives,property,and crucial engineering constructions.Annually,landslides lead to tens of thousands of fatalities(see the paper of"List of typical catastrophic landslides from March 2004 to February 2024"in this issue,doi:10.31035/cg2024079)and cause economic damages amounting to billions of dollars around the world,as well as disrupting crucial infrastructures such as railways,highways。 展开更多
关键词 hazards survey DOLLAR
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Survey on performance of vertical slot and nature-like fishways at Angu hydropower station, Southwest China
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作者 Jun-jian Sun Jia-yue Shi +2 位作者 Qi Zhang Xiao-tao Shi Jun-jun Tan 《Water Science and Engineering》 EI CAS CSCD 2024年第1期83-91,共9页
To restore dam-blocked natural fish migratory passages,a growing number of artificial fishways have been built in water conservancy and hydropower projects in China.The Angu hydropower station involved diverse importa... To restore dam-blocked natural fish migratory passages,a growing number of artificial fishways have been built in water conservancy and hydropower projects in China.The Angu hydropower station involved diverse important fish habitats in the lower reaches of the Daduhe River in Southwest China.Therefore,a vertical slot fishway(VSF)and a nature-like fishway(NLF)were built near the backwater area of the reservoir to connect the upstream and downstream habitats.Hydrodynamic and aquatic ecological surveys were conducted after the completion of the project to estimate the fish passing effect of the two fishways.The results indicated that both fishways were in effective operation and could maintain the desired hydrodynamic conditions and be used by several local fish species.During the survey,149 fish from 15 species and 111 fish from 17 species were captured by the traps in the VSF and NLF,respectively,while 1263 fish from 27 species were found in the downstream area.Some species captured in the VSF were not found in the NLF,and vice versa,which implied the different preferences of fish.Meanwhile,3789 signals including 2099 upward ones and 1690 downward ones were monitored with an ultrasonic fish detector at the inlet of the VSF.These findings revealed the characteristics of fish species observed in and near the fishways and provided valuable insights into the different fish passing capabilities of VSFandNLF. 展开更多
关键词 Vertical slot fishway Nature-like fishway Aguatic ecological survey Fishwaymonitoring Statistical analysis
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Diagnostic values of questionnaires of Convergence Insufficiency Symptom Survey and College of Optometrists Vision Development Quality of Life in the screening of convergence insufficiency
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作者 Ling Xiong Qian Chen Ye Wu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第5期904-908,共5页
AIM:To compare and analyse the diagnostic efficacy of the College of Optometrists Vision Development Quality of Life Questionnaire(COVD-QOL)and the Convergence Insufficiency Symptom Survey(CISS)in detecting convergenc... AIM:To compare and analyse the diagnostic efficacy of the College of Optometrists Vision Development Quality of Life Questionnaire(COVD-QOL)and the Convergence Insufficiency Symptom Survey(CISS)in detecting convergence insufficiency and to compare their diagnostic value in clinical applications.METHODS:Using the diagnostic test method,62 adult patients with convergence insufficiency(age:24.74±3.75y)and 62 normal participants(age:23.61±3.13y)who visited the Optometry Clinic of West China Hospital of Sichuan University from April 2021 to January 2023 were included.All subjects completed the CISS and COVD-QOL.Statistical analysis of the sensitivity and specificity of the CISS and COVD-QOL and comparison and joint experimental analysis of their diagnostic efficacy were performed.RESULTS:The sensitivity of the CISS and COVD-QOL for convergence insufficiency was 64.5%and 71.0%,respectively,while the specificity was 96.8%and 67.7%,respectively.Compared to the CISS alone,the combination of the CISS and COVD-QOL demonstrated lower sensitivity and specificity.The areas under the receiver operating characteristic curve of CISS,COVD-QOL and CISS combined with COVD-QOL were 0.806,0.694 and 0.782,respectively.CONCLUSION:Considering the low sensitivity of the CISS and the low specificity of the COVD-QOL,it is recommended to supplement these questionnaires with other screening tests for the detection of convergence insufficiency. 展开更多
关键词 convergence insufficiency symptom survey College of Optometrists Vision Development Quality of Life Questionnaire convergence insufficiency ASTHENOPIA
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油茶象甲Curculio chinensis基因组Survey测序分析
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作者 张丽 吴佳茜 +2 位作者 曾萝琦 刘惠 汤小宇 《中国农学通报》 2024年第17期135-141,共7页
油茶象甲Curculio chinensis Chevrolat是危害中国特有木本油料树种——油茶的专性蛀果害虫,也是中国林业危险性有害生物之一,在中国不同油茶产区均有分布,对油茶的为害呈加重趋势。为了深入研究其遗传基础和寄主适应性,确定适合鞘翅目... 油茶象甲Curculio chinensis Chevrolat是危害中国特有木本油料树种——油茶的专性蛀果害虫,也是中国林业危险性有害生物之一,在中国不同油茶产区均有分布,对油茶的为害呈加重趋势。为了深入研究其遗传基础和寄主适应性,确定适合鞘翅目象甲科基因组测序研究策略,首先采取Survey测序,之后做深度基因组测序和大规模种群测序。研究采用二代高通量测序技术(MGISEQ-2000),测定了油茶象甲基因组大小,并估计该物种基因组的杂合度、重复率和GC含量。结果显示:油茶象甲基因组大小约为1356.82 Mb,测序深度达到50×;K-mer分析油茶象甲基因组虽然具有杂合峰,但杂合率较低,为1.20%;基因组重复序列含量约为77%。该研究结果对于揭示油茶象甲适应性进化具有重要意义,可为后续构建完整基因组和多种群基因组测序提供策略选择依据。 展开更多
关键词 油茶象甲 鞘翅目 survey测序 杂合率 GC含量
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Functional Confirmation Using a Medical X-Ray System of a Semiconductor Survey Meter
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作者 Katsunao Suzuki Toru Negishi +2 位作者 Yoh Kato Yasuhisa Kono Michiharu Sekimoto 《Open Journal of Radiology》 2024年第1期1-13,共13页
In recent years, semiconductor survey meters have been developed and are in increasing demand worldwide. This study determined if it is possible to use the X-ray system installed in each medical facility to calculate ... In recent years, semiconductor survey meters have been developed and are in increasing demand worldwide. This study determined if it is possible to use the X-ray system installed in each medical facility to calculate the time constant of a semiconductor survey meter and confirm the meter’s function. An additional filter was attached to the medical X-ray system to satisfy the standards of N-60 to N-120, more copper plates were added as needed, and the first and second half-value layers were calculated to enable comparisons of the facility’s X-ray system quality with the N-60 to N-120 quality values. Next, we used a medical X-ray system to measure the leakage dose and calculate the time constant of the survey meter. The functionality of the meter was then checked and compared with the energy characteristics of the meter. The experimental results showed that it was possible to use a medical X-ray system to reproduce the N-60 to N-120 radiation quality values and to calculate the time constant from the measured results, assuming actual leakage dosimetry for that radiation quality. We also found that the calibration factor was equivalent to that of the energy characteristics of the survey meter. 展开更多
关键词 Semiconductor survey Meter Functional Confirmation Medical X-Ray System Calibration Factor Time Constant
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Environmental Impact Assessment Follow-Up of Seismic Survey Offshore Activities in Brazil
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作者 Fontes Nuno Eduardo Paulo Marcelo Montaño 《Journal of Environmental Protection》 2024年第2期141-155,共15页
Follow-up of environmental impacts is an integral part of the Environmental Impact Assessment (EIA) process, closely related to the effectiveness of the instrument. EIA follow-up has been receiving a lot of interest f... Follow-up of environmental impacts is an integral part of the Environmental Impact Assessment (EIA) process, closely related to the effectiveness of the instrument. EIA follow-up has been receiving a lot of interest from scientists and practitioners, though it is recognized as one of the weakest points of EIA systems globally. Also, EIA follow-up is influenced by the context, mainly in terms of the types of projects or activities and their related impacts on the environment. Therefore, the present paper is focused on the investigation of the follow-up stage applied to the activity of seismic survey coupled with offshore oil & gas exploitation in Brazil. Research was based on a qualitative approach that included document analysis and semi-structured interviews with analysts involved in EIA processes, and sought to generate evidence of effectiveness of the EIA follow-up as conducted by the Federal Environment Agency (Ibama) in order to situate the practice of follow-up in the broader context of international best practice principles. Based on the findings, it was concluded that, due to the peculiarities of offshore seismic survey, it is necessary to promote adaptations in the procedures for monitoring impacts in order to ensure proper alignment with the principles and conceptual foundations that guide EIA practice. Specifically, the timing of the execution of the activity imposes challenges for its integration into the “conventional” cycle that has guided the monitoring of the impacts in the EIA of projects. 展开更多
关键词 Environmental Impact Assessment Follow-Up Follow-Up Effectiveness Oil and Gas Offshore Seismic survey
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黄鲫的全基因组survey分析与微卫星分布特征
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作者 郑思旭 陈诗逸 +5 位作者 梁旭东 王云鹏 沈豪迪 黄文化 柳意樊 刘炳舰 《浙江海洋大学学报(自然科学版)》 CAS 2024年第2期93-100,共8页
对黄鲫进行了全基因组测序,并进行了survey分析和微卫星特征研究,旨在评估其基因组基本信息并为进一步研究该物种的遗传多样性和进化提供重要信息。研究表明,黄鲫基因组大小约为815Mb,重复序列比例为39.69%,杂合率为1.77%;通过初步组装... 对黄鲫进行了全基因组测序,并进行了survey分析和微卫星特征研究,旨在评估其基因组基本信息并为进一步研究该物种的遗传多样性和进化提供重要信息。研究表明,黄鲫基因组大小约为815Mb,重复序列比例为39.69%,杂合率为1.77%;通过初步组装,得到的ContigN50为35836bp,ScaffoldN50为107605bp。此外,在全基因组范围内,检测出了14.562379个微卫星位点,相对丰度约1713个·Mb^(-1);其中,二碱基重复最常见(90.64%),其次为单碱基重复(5.52%),6碱基重复较少(0.24%)。微卫星重复拷贝数主要分布在6~15次之间,AC/GT和AG/CT是最常见的2碱基重复类型。这些研究结果为黄鲫的遗传学及进化生物学研究提供了重要的信息,并且为黄鲫的遗传多样性保护提供了有用的分子标记。 展开更多
关键词 黄鲫 高通量测序 全基因组survey 微卫星标记
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Analysis of GPS Technology in Surveying and Mapping Engineering Technology
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作者 Hanyu Zhao 《Journal of World Architecture》 2024年第2期84-89,共6页
With the rapid advancement of digital and information technology,global positioning system(GPS)technology has seen increasing utilization in surveying and mapping engineering,extending its application across land,ocea... With the rapid advancement of digital and information technology,global positioning system(GPS)technology has seen increasing utilization in surveying and mapping engineering,extending its application across land,ocean,and various other domains.By analyzing the technical means of GPS in surveying and mapping engineering,understanding the characteristics and key technologies in different application environments,and exploring the application process and key technical means,accurate control can be effectively realized.Based on this,this paper mainly analyzes the specific application of GPS technology in surveying and mapping engineering technology for reference. 展开更多
关键词 surveying and mapping engineering technology GPS technology
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Insync Surveys图书馆用户满意度调查分析 被引量:8
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作者 张为杰 杨广锋 周婕 《图书情报知识》 CSSCI 北大核心 2009年第6期34-38,86,共6页
Insync Surveys,原名Ambit Insights/Rodski Survey Research,是澳大利亚一家调查服务公司。其用户满意度调查自1998年在墨尔本大学图书馆实施以来,影响不断扩大,并与CAUL建立了稳定的合作关系。Insync Surveys以关注度-满意度为方法基... Insync Surveys,原名Ambit Insights/Rodski Survey Research,是澳大利亚一家调查服务公司。其用户满意度调查自1998年在墨尔本大学图书馆实施以来,影响不断扩大,并与CAUL建立了稳定的合作关系。Insync Surveys以关注度-满意度为方法基础,指标体系灵活调整,并提供基本调查和全面调查两种服务模式,取得了良好的实践效果。 展开更多
关键词 Insync surveys Rodski 满意度调查 服务质量评估
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黑壳楠染色体核型分析及基因组Survey预测
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作者 逯久幸 刘燕 +3 位作者 许朵朵 陈鹏 李永华 刘红利 《河南农业大学学报》 CAS CSCD 2023年第6期967-974,共8页
【目的】明确黑壳楠(Lindera megaphylla)染色体形态结构特征和基因组基本信息。【方法】以野生黑壳楠为材料,采用荧光原位杂交法,对染色体进行核型分析,并通过基因组survey预测了黑壳楠基因组的基本信息。【结果】黑壳楠染色体数目为2n... 【目的】明确黑壳楠(Lindera megaphylla)染色体形态结构特征和基因组基本信息。【方法】以野生黑壳楠为材料,采用荧光原位杂交法,对染色体进行核型分析,并通过基因组survey预测了黑壳楠基因组的基本信息。【结果】黑壳楠染色体数目为2n=24,核型公式为2n=2X=24=18m(2SAT)+6sm,9号染色体存在1对随体,属于2B型染色体。染色体组绝对长度变异范围为2.92~5.83,相对长度的变化范围为5.33%~11.11%,核型不对称系数为59.49%。研究还发现,存在1对5S rDNA杂交位点和1对18S rDNA杂交位点,分别位于5号和9号染色体。18S rDNA杂交位点2个杂交信号位置相同、强度近似。基因组survey结果显示,黑壳楠基因大小为1.38 Gb,杂合率为0.8%,重复序列比例为70%。【结论】黑壳楠为2倍体,染色体数目为24条,核型相对对称。黑壳楠在樟科的进化中属于较为原始的物种,且染色体未发生重组、变异或者种内杂交等现象。黑壳楠为大基因组,杂合率较高,重复序列多的物种。 展开更多
关键词 黑壳楠 核型分析 荧光原位杂交 基因组survey
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Analysis of the Results of Two Nationwide Surveys on Clonorchis sinensis Infection in China 被引量:22
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作者 CHEN Ying Dan ZHOU Chang Hai XU Long Qi 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2012年第2期163-166,共4页
Objective To examine Clonorchis sinensis infection in China and evaluate the effectiveness of efforts to prevent and control it,two nationwide surveys were undertaken in 31 provinces,autonomous regions,and municipalit... Objective To examine Clonorchis sinensis infection in China and evaluate the effectiveness of efforts to prevent and control it,two nationwide surveys were undertaken in 31 provinces,autonomous regions,and municipalities(PAMs) during 1988-92(the 1990 survey) and during 2001-04(the 2003 survey).Methods During the period 2001-04,two sampling methods were applied.The first method repeated the stratified cluster random sampling used in the 1990 survey;the second method applied two-characteristic stratified cluster random sampling in 27 PAMs—the 2003 endemic area(EA) survey.The Kato-Katz thick smear method was used for the nationwide survey.Results The infection rates of Clonorchis sinensis in the 1990 and 2003 surveys were 0.311% and 0.579%,respectively.The infection rate was 2.40% in the 2003 EA survey,and it was estimated that 12.49 million people in China were infected with Clonorchis sinensis.Conclusion The 2003 survey showed that the standardized infection rate of Clonorchis sinensis increased by 74.85% compared with the 1990 survey.The infection rate in males was higher than in females;the infection rate among people eating raw fish or eating out frequently was higher than among those who did not. 展开更多
关键词 Clonorchis sinensis Two nationwide surveys The status of infection in China
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Using seismic surveys to investigate sediment distribution and to estimate burial fluxes of OC, N, and P in a canyon reservoir 被引量:4
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作者 Ningxiao Yu Yong Qin +2 位作者 Feng Hao Yunchao Lang Fushun Wang 《Acta Geochimica》 EI CAS CSCD 2019年第6期785-795,共11页
As a high-precision survey method,seismic surveying has been increasingly applied to inland water research,although its application to artificial reservoirs has remained limited.As a special artificial water body,rese... As a high-precision survey method,seismic surveying has been increasingly applied to inland water research,although its application to artificial reservoirs has remained limited.As a special artificial water body,reservoirs have important effects on the fluvial transport of material from land to ocean,and inevitably have complex terrain which can complicate and distort the results of seismic surveys.Therefore,there are still some problems need to be resolved in the application of seismic surveys in reservoirs with complex terrain.For this study,the Dongfeng Reservoir located in the upper reaches of the Wujiang River was chosen as an example to test the seismic survey method.Our testing showed that(1)because of the complex underwater terrain,the signal-to-noise ratio of the echo signal in canyon reservoir is low,making it difficult to determine sediment layers thicknesses in some areas;and(2)due to the large spatial heterogeneity of sediment distribution,insufficient density of cross-sections can lead to inaccurate interpolation results.To improve the accuracy of calculations,a mathematical method was used.Ultimately,the total burial mass of sediment was estimated at 2.85 x 107 tons,and the average burial rates of total organic carbon,total phosphorus,and total nitrogen were estimated at 0.194,0.011,and 0.014 g cm-2 year-1,respectively.These values were close to the results of previous studies and hydrographic station data,indicating that seismic survey can be a reliable and efficient method for the mapping of reservoirs. 展开更多
关键词 Dongfeng Reservoir Seismic survey SEDIMENTATION Nutrients burial fluxes
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Taxonomy is the cornerstone of biodiversity conservation SEABRI reports on biological surveys in Southeast Asia 被引量:3
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作者 Shu-Qiang Li Rui-Chang Quan 《Zoological Research》 CAS CSCD 2017年第5期213-213,共1页
The Southeast Asia Biodiversity Research Institute (SEABRI) is an international scientific research and education organization affiliated directly to the Chinese Academy of Sciences (CAS) and managed by the Xishua... The Southeast Asia Biodiversity Research Institute (SEABRI) is an international scientific research and education organization affiliated directly to the Chinese Academy of Sciences (CAS) and managed by the Xishuangbanna Tropical Botanical Garden (XTBG). By harnessing its connections with all CAS institutes, local institutes and international agencies and leveraging on their resources, it seeks to make a significant contribution to biodiversity conservation in Southeast Asia. 展开更多
关键词 In SEABRI reports on biological surveys in Southeast Asia Taxonomy is the cornerstone of biodiversity conservation
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Preface: The LAMOST Galactic surveys and early results 被引量:4
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作者 Xiao-Wei Liu Gang Zhao Jin-Liang Hou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第8期1089-1094,共6页
By the time of this writing, the ongoing LAMOST Galactic surveys have collected approximately 4.5 million stellar spectra with signal-to-noise ratios better than 10 per pixel. This special issue is devoted to early re... By the time of this writing, the ongoing LAMOST Galactic surveys have collected approximately 4.5 million stellar spectra with signal-to-noise ratios better than 10 per pixel. This special issue is devoted to early results from the surveys, mostly based on the LAMOST Data Release 1 (DR1; Luo et al., this volume) that contains data secured by May 2013, the end of the first year of regular surveys, al- though a few studies have made use of data collected in the second year of regular surveys. LAMOST DR1 was released to the Chinese astronomical community and international partners in August 2013 and made public to the whole world in March 2015. Here we briefly review the scope and motivation, data reduction and release, as well as early results of the surveys. As the project advances, one can expect that these surveys will yield an exquisite description of the distribution, kinematics and chemistry of Galactic stellar populations, especially those within a few kpc of the Sun, a robust measurement of the local dark matter density, and, consequently, shed light on how our Galaxy, and other galaxies in general, form and evolve. 展开更多
关键词 Telescope: LAMOST -- Milky Way general -- Spectroscopy survey
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The usability of GNSS mass-market receivers for cadastral surveys considering RTK and NRTK techniques 被引量:2
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作者 Paolo Dabove 《Geodesy and Geodynamics》 2019年第4期282-289,共8页
Nowadays many positioning techniques and methods are applied to the cadastral surveys. Starting from last decade, GPS/GNSS positioning had become one of the most used methodology thanks to the rapid development of sat... Nowadays many positioning techniques and methods are applied to the cadastral surveys. Starting from last decade, GPS/GNSS positioning had become one of the most used methodology thanks to the rapid development of satellite-based positioning and to the appearance of GNSS mass-market receivers and antennas. Methods based on these instruments are more affordable than the conventional ones even if their use for precise positioning is not so intuitive. This study is aimed to evaluate the use of singlefrequency GPS/GNSS mass-market receivers for cadastral surveys, considering both single-base RealTime Kinematic(RTK) and Network Real-Time Kinematic(NRTK) methodologies. Furthermore, a particular tool for predicting and estimating the occurrence of false fix of the phase ambiguities has been considered, in order to improve the accuracy and precision of the solutions. Considering the single-base positioning, the research results showed the difference of a few centimetres between the reference coordinates and the estimated ones if the distance between master and rover is less than 3 km, while considering the network positioning and the Virtual Reference Station correction, the difference are about a couple of centimetres for East and North component, and about 5 cm for the Up. 展开更多
关键词 GNSS CADASTRAL surveying RTK NRTK positioning Mass-market RECEIVERS
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The Uses and Benefits of Big Data for Geological Surveys 被引量:1
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作者 Michael H.STEPHENSON 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第S01期64-65,共2页
’Long tail’data is the difficult-to-get-at data that sits in libraries,institutes and on the computers of individual scientists.Informatics specialists like to contrast it with the smaller number of large,more acces... ’Long tail’data is the difficult-to-get-at data that sits in libraries,institutes and on the computers of individual scientists.Informatics specialists like to contrast it with the smaller number of large,more accessible data sets(e.g.Sinha et al.,2013).The name’long tail’derives from graphs drawn of the size of data sets against their number:there are relatively few large datasets and a lot of smaller ones. 展开更多
关键词 LONG TAIL data informatics BIOSTRATIGRAPHY GEOLOGICAL survey
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Research achievements of the Qinghai-Tibet Plateau based on 60 years of aeromagnetic surveys 被引量:3
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作者 Sheng-qing Xiong 《China Geology》 2021年第1期147-177,共31页
The Qinghai-Tibet Plateau(also referred to as the Plateau)has long received much attention from the community of geoscience due to its unique geographical location and rich mineral resources.This paper reviews the aer... The Qinghai-Tibet Plateau(also referred to as the Plateau)has long received much attention from the community of geoscience due to its unique geographical location and rich mineral resources.This paper reviews the aeromagnetic surveys in the Plateau in the past 60 years and summarizes relevant research achievements,which mainly include the followings.(1)The boundaries between the Plateau and its surrounding regions have been clarified.In detail,its western boundary is restricted by West Kunlun-Altyn Tagh arc-shaped magnetic anomaly zone forming due to the arc-shaped connection of the Altyn Tagh and Kangxiwa faults and its eastern boundary consists of the boundaries among different magnetic fields along the Longnan(Wudu)-Kangding Fault.Meanwhile,the fault on the northern margin of the Northern Qilian Mountains serves as its northern boundary.(2)The Plateau is mainly composed of four orogens that were stitched together,namely East Kunlun-Qilian,Hoh-Xil-Songpan,Chamdo-Southwestern Sanjiang(Nujiang,Lancang,and Jinsha rivers in southeastern China),and Gangdese-Himalaya orogens.(3)The basement of the Plateau is dominated by weakly magnetic Proterozoic metamorphic rocks and lacks strongly magnetic Archean crystalline basement of stable continents such as the Tarim and Sichuan blocks.Therefore,it exhibits the characteristics of unstable orogenic basement.(4)The Yarlung-Zangbo suture zone forming due to continent-continent collisions since the Cenozoic shows double aeromagnetic anomaly zones.Therefore,it can be inferred that the Yarlung-Zangbo suture zone formed from the Indian Plate subducting towards and colliding with the Eurasian Plate twice.(5)A huge negative aeromagnetic anomaly in nearly SN trending has been discovered in the middle part of the Plateau,indicating a giant deep thermal-tectonic zone.(6)A dual-layer magnetic structure has been revealed in the Plateau.It consists of shallow magnetic anomaly zones in nearly EW and NW trending and deep magnetic anomaly zones in nearly SN trending.They overlap vertically and cross horizontally,showing the flyover-type geological structure of the Plateau.(7)A group of NW-trending faults occur in eastern Tibet,which is intersected rather than connected by the nearly EW trending that develop in middle-west Tibet.(8)As for the central uplift zone that occurs through the Qiangtang Basin,its metamorphic basement tends to gradually descend from west to east,showing the form of steps.The Qiangtang Basin is divided into the northern and southern part by the central uplift zone in it.The basement in the Qiangtang Basin is deep in the north and west and shallow in the south and west.The basement in the northern Qiangtang Basin is deep and relatively stable and thus is more favorable for the generation and preservation of oil and gas.Up to now,19 favorable tectonic regions of oil and gas have been determined in the Qiangtang Basin.(9)A total of 21 prospecting areas of mineral resources have been delineated and thousands of ore-bearing(or mineralization)anomalies have been discovered.Additionally,the formation and uplift mechanism of the Plateau are briefly discussed in this paper. 展开更多
关键词 Aeromagnetic survey Tectonic framework Suture zone FAULT Magnetic rocks UPLIFT Oil and gas resource assessment Ore prospecting Qinghai-Tibet Plateau
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