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41.
工程勘察设计信息集成化系统的实施状况及其思考 总被引:1,自引:0,他引:1
国家建设部“全国工程勘察设计行业2000~2005年计算机应用工程及信息化发展规划纲要”发布后,备受工程设计企业关注,但推行情况却不甚理想。本文通过阐述信息集成化系统的主要任务和目标,分析其应用状况,寻求推广受阻原因,提出了开发该系统的思路和改善其实施环境的建议。 相似文献
42.
云南东北部拱王山末次冰期 总被引:1,自引:0,他引:1
1 Introduction The Gongwang mountains constitute one of the few high m ountains of irrefutable late Pleistocene glaciation in eastern China. This area is one of the m ost extensively studied Quaternary geologicallocationsin eastern China and the interpret… 相似文献
43.
Zhu Yu Wei Jun Yang Manjuan Li Hao Liu Hongqing 《中国地质大学学报(英文版)》2005,16(3):277-282
INTRODUCTION Tunnel typeanchoragehasobviousadvantages inbearingcapacityversusinvestment(LiuandHu,1996).However,itisrarelyusedinapracticalpro jectbecauseofitsrequirementofgoodrockcondi tions.Siduhebridge(Fig.1),whichliesintheBa dongmountainsinthewestplatea… 相似文献
44.
2001年,广州海洋地质调查局对“探宝号”船原有震源更新升级为阵列可变的BOLT震源系统。随着更新改造工程的成功,该船已成为具备承担高分辨率、常规、低频深水油气地震勘探的多功能地震调查船。本文介绍了地震勘探震源的基本工作原理以及三种阵列的分布、波形、频谱等特性。 相似文献
45.
Geochemistry and occurrence of inorganic gas accumulations in Chinese sedimentary basins 总被引:15,自引:0,他引:15
Inorganic gases are commonly seen in eastern China and occasionally in southern China from the shallow water columns above hot and cold springs. The gases contain 68% to nearly 100% CO2, with δ13CCO2 and δ13C1 values in the range of −1.18‰ to −6.00‰ and −19.48‰ to −24.94‰, respectively. All of the 34 large inorganic CO2 and one inorganic methane accumulations discovered in China are distributed in eastern parts of the country, from both onshore and continental shelf basins. No commercial inorganic gas accumulation has been found in central and western China. This is a review of the occurrence and geochemical characteristics of inorganic gas accumulations in Chinese sedimentary basins. A detailed study of gas samples collected from four representative inorganic CO2 pools and one possible inorganic methane pool indicates that inorganic alkane gases typically show δ13C1 values greater than −10‰ versus PDB (mostly −30‰), with a positive stable carbon isotope sequence of δ13C1 < δ 13C2 < δ13C3 < δ 13C4. In contrast, the δ13C1 values of biogenic alkane gases are lighter than −30‰, with a negative isotope sequence (i.e. δ13C1 > δ13C2 > δ 13C3 > δ13C4). Inorganic gases also tend to show less negative δ13CCO2 values (−10‰) than biogenic gases (<−10‰). 相似文献
47.
Guo-Wei Ren Hao-Jing Zhang Xiong Zhang Nan Ding Xing Yang Fu-Ting Li Pei-Lin Yan Xiao-Lin Xu 《天文和天体物理学研究(英文版)》2021,(3):243-250
In this work,we have searched for quasi-periodic oscillations(QPOs)in the 15 GHz light curve of the FSRQ PKS J0805-0111 monitored by the Owens Valley Radio Observatory(OVRO)40 m telescope during the period from 2008 January 9 to 2019 May 9,using the weighted wavelet Z-transform(WWZ)and the Lomb-Scargle Periodogram(LSP)techniques.This is the first time to search for a periodic radio signal in the FSRQ PKS J0805-0111 by these two methods.Both methods consistently reveal a repeating signal with a periodicity of 3.38±0.8 yr(>99.7%confidence level).In order to determine the significance of the periods,the false alarm probability method was applied,and a large number of Monte Carlo simulations were performed.As possible explanations,we discuss a number of scenarios including the thermal instability of thin disks scenario,the spiral jet scenario and the binary supermassive black hole scenario.We expect that the binary black hole scenario,where the QPO is caused by the precession of binary black holes,is the most likely explanation.FSRQ PKS J0805-0111 thus could be a good binary black hole candidate.In the binary black hole scenario,the distance between the primary black hole and the secondary black hole is about 1.71×1016 cm. 相似文献
48.
以综合催熟措施和移植精荚手术相结合的技术方法,解决了鱼塭产斑节对虾催熟效应期长,产卵率低,易蜕壳失去精荚等难题。使用 278 尾雌虾,催熟率达90% 以上,在40 d 内共产卵608 尾次,卵量18 530 万粒,孵出无节幼体11 998 万尾,平均孵化率 64.7% ,平均每尾雌虾孵出无节幼体 43.1 万尾,育成商品虾苗 1 028.5 万尾,育苗平均成活率 13.6% ,试养成活率57.1% 相似文献
49.
GUO Mengyao SHE Dunxian ZHANG Liping LI Lingcheng YANG Zong-Liang HONG Si 《地理学报(英文版)》2021,31(8):1123-1139
This study uses two forms of the Palmer Drought Severity Index(PDSI), namely the PDSI_TH(potential evapotranspiration estimated-by the Thornthwaite equation) and the PDSI_PM(potential evapotranspiration estimated by the FAO Penman-Monteith equation), to characterize the meteorological drought trends during 1960–2016 in the Loess Plateau(LP) and its four subregions. By designing a series of numerical experiments, we mainly investigated various climatic factors' contributions to the drought trends at annual, summer, and autumn time scales. Overall, the drying trend in the PDSI_TH is much larger than that in the PDSI_PM. The former is more sensitive to air temperature than precipitation, while the latter is the most sensitive to precipitation among all meteorological factors. Increasing temperature results in a decreasing trend(drying) in the PDSI_TH, which is further aggravated by decreasing precipitation, jointly leading to a relatively severe drying trend. For the PDSI_PM that considers more comprehensive climatic factors, the drying trend is partly counteracted by the declining wind speed and solar radiation. Therefore, the PDSI_PM ultimately shows a much smaller drying trend in the past decades. 相似文献
50.
杨绍勇 《高原山地气象研究》2007,27(1)
雷电破坏性极强,如何防雷避雷,降低雷击损失,一直是人们十分关注的话题.本文根据一次雷击实例,详细分析了701C测风雷达被雷击的根本原因,提出了预防雷击的具体措施. 相似文献