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Technical status and development direction of workover operation of PetroChina 认领
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作者 LEI Qun LI Yiliang +7 位作者 LI Tao LI Hui GUAN Baoshan BI Guoqiang WANG Jialu WENG Dingwei HUANG Shouzhi HAN Weiye 《石油勘探与开发:英文版》 2020年第1期161-170,共10页
Through a comprehensive review of the development status of workover technology of PetroChina Company Limited(PetroChina), this paper presents the connotation of workover operation under the background of the new era,... Through a comprehensive review of the development status of workover technology of PetroChina Company Limited(PetroChina), this paper presents the connotation of workover operation under the background of the new era, the latest progress of workover operation in the respects of equipment, tools, technology and the construction of information and standardization. The gaps between PetroChina and foreign counterpart in workover technology are as follows: the level of automation and intellectualization of tools and equipment is relatively low, the snubbing operation in gas wells characterized by HT/HP and high H2 S is lagged behind;water plugging in the long horizontal wellbore needs to be further developed, coiled tubing and its relevant equipment for ultra-deep well operation has to be optimized;informationization, standardization and big data application of workover operation need to be started. Based on this as well as the development status of workover technology in China and the technical difficulties faced in the future, eight suggestions for future development are put forward:(1) strengthen the dynamic understanding of reservoir and improve the pertinence of workover schemes;(2) develop the general overhaul technology in a systematical way to tackle issues of seriously problematic wells;(3) put more efforts into the research of horizontal well workover operation and develop relevant technology for long horizontal section operation;(4) improve the snubbing technology and extend its applications;(5) expand the capacity of coiled tubing operation and improve the level of special operations;(6) develop automatic workover technology into the field of artificial intelligence;(7) promote clean operation in an all-round way and build green oil and gas fields;(8) perfect the informationization construction to realize the sharing of workover resources. 展开更多
关键词 WORKOVER operation WORKOVER equipment WORKOVER TOOLS WORKOVER TECHNOLOGY DEVELOPMENT STATUS DEVELOPMENT direction
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煤矿区煤层气开发利用新技术现状及发展趋势 认领
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作者 刘见中 孙海涛 +1 位作者 雷毅 曹偈 《煤炭学报》 EI CAS CSCD 北大核心 2020年第1期258-267,共10页
“十二五”以来,我国煤矿区煤层气开发利用技术取得了巨大的进步,虽然我国煤矿数量由近20000对直线下降到了不足5800对,但煤层气产量仍由2010年的88亿m 3提高到了2018年的184亿m 3,利用率亦提升了10%,科技对产业的贡献巨大;但是也出现... “十二五”以来,我国煤矿区煤层气开发利用技术取得了巨大的进步,虽然我国煤矿数量由近20000对直线下降到了不足5800对,但煤层气产量仍由2010年的88亿m 3提高到了2018年的184亿m 3,利用率亦提升了10%,科技对产业的贡献巨大;但是也出现了单井排采产量低、气源分散性高等新的问题。因此,全面梳理了近10 a煤矿区地面抽采技术装备、井下抽采技术装备和煤矿区高、低浓度煤层气利用技术装备的科技创新及应用效果等,阐述了煤矿区煤层气开发利用在三级瓦斯地质分析技术、碎软低渗煤层地面井分段压裂顶板技术、煤层群分层控压联合排采技术、采动区地面L型顶板水平井技术、井下千米定向长钻孔技术、碎软煤层井下护孔钻进技术、智能化钻机远控钻孔技术、井下水力化压裂/割缝增渗技术等煤层气抽采技术及其配套装备最新进展和中高浓度煤层气深冷液化、低浓度煤层气分级压缩提浓、超低浓度煤层气蓄热氧化利用等煤层气利用装备的最新进展及技术指标。在此基础上,针对我国目前面临的深部开采、西部煤炭资源开发及高强度集约化开采等新特点,分类整理了束缚煤层气产业发展的技术瓶颈和发展趋势,提出了煤炭开采与煤层气开发协同规划和联合开发的技术思路等。 展开更多
关键词 煤矿区 煤层气 开发 利用 发展趋势
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国内外集装箱跨运车发展情况及趋势分析 认领
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作者 马超超 赵重年 +2 位作者 王文强 高少杰 邱国权 《起重运输机械》 2020年第1期40-45,共6页
集装箱跨运车在集装箱运输业中发挥着至关重要的作用,广泛应用于港口码头,文中概述了其应用情况,详细介绍了跨运车国内外发展概况及特点,并对其未来的发展趋势进行了分析,为相关专用车辆后续研发提供了理论依据。
关键词 集装箱跨运车 发展情况 特点 发展趋势
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An Empirical Analysis on the Impact of Rural Financial Development on the Income Gap between Urban and Rural Residents in Heilongjiang Province 认领
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作者 Guanghe HAN Jiayu ZHOU +1 位作者 Siqi LI Zhiming SHEN 《亚洲农业研究:英文版》 2020年第2期1-7,10共8页
The high-quality development of rural finance is an important support for rural revitalization.In recent years,it continuously expands the investment in rural finance in Heilongjiang Province,and optimizes the rural f... The high-quality development of rural finance is an important support for rural revitalization.In recent years,it continuously expands the investment in rural finance in Heilongjiang Province,and optimizes the rural financial service system and mechanism.The overall income level and living conditions of rural residents have been significantly improved,but there still exists income gap between urban and rural residents.Therefore,based on analyzing and combing current situation and problems of rural financial development and urban-rural income gap in Heilongjiang Province,multiple linear regression model is used to study the impact of rural financial development on the income gap between urban and rural residents in Heilongjiang Province.The research results show that the scale of rural financial development in Heilongjiang Province will enlarge the income gap between urban and rural residents,while rural financial development efficiency and urbanization level reduce income gap between urban and rural residents in Heilongjiang Province.Based on the above conclusions,some policy suggestions to promote the equalization of urban and rural income in Heilongjiang Province are puts forward in this paper. 展开更多
关键词 RURAL FINANCE INCOME GAP between urban and RURAL areas DEVELOPMENT scale DEVELOPMENT efficiency
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A Study on the Interaction among Financial Development,Industrial Adjustment and Urbanization 认领
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作者 Yang YANG 《亚洲农业研究:英文版》 2020年第4期20-23,共4页
This paper attempts to study the interactive relationship among financial development,industrial structure adjustment and urbanization in China.Based on the data from 1978 to 2018,this paper establishes a VAR model fo... This paper attempts to study the interactive relationship among financial development,industrial structure adjustment and urbanization in China.Based on the data from 1978 to 2018,this paper establishes a VAR model for empirical analysis.The results show that after the impulse response analysis and variance decomposition of the model,industrial structure adjustment and urbanization have a positive impact on financial development in the long run.Financial development and industrial structure adjustment do not play a positive role in the process of urbanization,and there is still room for further development.It is suggested that the state should strengthen the financial support for urbanization so that the two can develop in coordination.At the same time,we should adhere to the simultaneous development of industrial structure adjustment and urbanization to ensure the simultaneous development of financial scale and efficiency. 展开更多
关键词 FINANCIAL DEVELOPMENT Industrial structure adjustment URBANIZATION DEVELOPMENT VAR model INTERACTIVE research
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中国城市绿色发展效率时空演变特征及影响因素 认领
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作者 周亮 周成虎 +1 位作者 车磊 王宝 《地理学报:英文版》 SCIE CSCD 2020年第5期724-742,共19页
To resolve conflicts between development and the preservation of the natural environment,enable economic transformation,and achieve the global sustainable development goals(SDGs),green development(GD)is gradually beco... To resolve conflicts between development and the preservation of the natural environment,enable economic transformation,and achieve the global sustainable development goals(SDGs),green development(GD)is gradually becoming a major strategy in the construction of an ecological civilization and the ideal of building a"beautiful China",alongside the transformation and reconstruction of the global economy.Based on a combination of the concept and implications of GD,we first used the Slacks Based Model with undesirable outputs(SBM-Undesirable),the Theil index,and the spatial Markov chain to measure the spatial patterns,regional differences,and spatio-temporal evolution of urban green development efficiency(UGDE)in China from 2005 to 2015.Second,by coupling natural and human factors,the mechanism influencing UGDE was quantitatively investigated under the framework of the human-environment interaction.The results showed that:(1)from 2005 to 2015,the UGDE increased from 0.475 to 0.523,i.e.,an overall increase of 10%.In terms of temporal variation,there was a staged increase,with its evolution having the characteristics of a"W-shaped"pattern.(2)The regional differences in UGDE followed a pattern of eastern>central>western.For different types of urban agglomeration,the UGDE had inverted pyramid cluster growth characteristics that followed a pattern of"national level>regional level>local level",forming a stable hierarchical scale structure of"super cities>mega cities>big cities>medium cities>small cities".(3)UGDE in China has developed with significant spatial agglomeration characteristics.High-efficiency type cities have positive spillover effects,while low-efficiency cities have negative effects.Different types of urban evolution processes have a path dependence,and a spatial club convergence phenomenon exists,in which areas with high UGDE are concentrated and drive low UGDE elsewhere.(4)Under the framework of regional human-environment interaction,the degree of human and social influence on UGDE is greater than that of th 展开更多
关键词 green development EFFICIENCY green city green economy spatial scale sustainable development goals(SDGs)
低渗透油田开发的难点和主要对策 认领
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作者 黄鑫鹏 王晓双 《云南化工》 CAS 2020年第4期150-151,共2页
近年来,低渗透油田已经成为我国重要的石油资源,但低渗透油田开发存在着许多困难,本文根据多年在油田从事井下工作的经验,对低渗透油田开发存在的困难提出一些对策。
关键词 低渗透油田 开发 难点 对策 发展趋势
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Designing a spatial pattern to rebalance the orientation of development and protection in Wuhan 认领
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作者 JIN Gui SHI Xin +3 位作者 HE Dawei GUO Baishu LI Zhaohua SHI Xianbin 《地理学报:英文版》 SCIE CSCD 2020年第4期569-582,共14页
Patterns of spatial development and protection form a basic category of geoscience,and redesigning them is a popular subject of research in regional sustainable development that is important for ecological civilizatio... Patterns of spatial development and protection form a basic category of geoscience,and redesigning them is a popular subject of research in regional sustainable development that is important for ecological civilization construction.The authors here report a case study of Wuhan city using the circuit theory model and minimum cumulative resistance(MCR)model to rebalance its spatial protection and development.The results show the following:(1)Using the density of the gross domestic product(GDP),density of population,rate of urbanization,and access to transportation as evaluation indicators,seven core areas of development in Wuhan were identified,accounting for 59%of the total number of streets,that exhibited a “circular-satellite”spatial structure.(2)According to the importance of ecosystem services,ecological sensitivity,land use type,and slope of the terrain,the resistance surface of spatial development in Wuhan had a stereoscopic spatial form of an“inverted pyramid,”with high surroundings and a low center.The area of low resistance accounted for 6.64%of the total area of Wuhan.(3)Based on coupling analysis using the MCR and spatial morphological characteristics of current,nine axes of spatial development with a total area of 427.27 km2 and eight key strategic points with a total area of 40.02 km2 were identified.Streets that were prioritized for development accounted for 9.63%of Wuhan's total area.(4)By combining the characterization of the development axis with the structure of the three-level core area,we extracted the structure of spatial development of "one heart,two wings,and three belts" in Wuhan.The research framework and empirical results can provide scientific guidance for the urban spatial layout,the development of regional linkages,and ecological environmental protection in China. 展开更多
关键词 spatial development and protection circuit theory model minimum cumulative resistance model core area development axis WUHAN
Research on the Development of Rural Collective Economy in Shandong Province 认领
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作者 Xiaoyan ZHANG Jingxue HE +1 位作者 Lili WANG Feng LIU 《亚洲农业研究:英文版》 2020年第3期15-19,共5页
The 19th National Congress of the Communist Party of China proposed a strategy for rural revitalization and made a scientific deployment.In this context,how to pursue the development of rural collective economy is of ... The 19th National Congress of the Communist Party of China proposed a strategy for rural revitalization and made a scientific deployment.In this context,how to pursue the development of rural collective economy is of great significance.Analysis on the status of the development of rural collective economy in Shandong Province showed that decentralized small farmers had a wide range of wealth,poor income-generating capacity,and weak income growth.The development models of rural collective economy in Shandong mainly included the follows:property leasing to explore the way to make money on the spot;relying on resources to build advantageous industries;creating a livable living environment led by capable persons;cooperative management to sound agricultural production and management system;and reform of property rights system to develop the collective economy.In addition,it also found that the rural collective economy in Shandong Province had weak economic foundations,uneven development,financing difficulties,debt resolution difficulties,lack of scientific support policies,and limited innovation and development of leadership team.In response to these problems,countermeasures and suggestions were put forward in this article. 展开更多
关键词 SHANDONG Province Rural COLLECTIVE economy DEVELOPMENT status DEVELOPMENT model Existing problem COUNTERMEASURE and SUGGESTION
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Development Imbalances in China:An Integrated Analysis with the Tsinghua China Balanced Development Index 认领
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作者 许宪春 郑正喜 张钟文 《中国经济学人:英文版》 2020年第3期2-17,共16页
The principal contradiction facing the Chinese society has evolved to be that between imbalanced and inadequate development and the people’s ever-growing needs for a better life.Given China’s vision for achieving mo... The principal contradiction facing the Chinese society has evolved to be that between imbalanced and inadequate development and the people’s ever-growing needs for a better life.Given China’s vision for achieving moderate prosperity,it is relevant to conduct theoretical and empirical studies on the nation’s development imbalances.As a quantitative index,the Tsinghua China Balanced Development Index measures the extent to which development is uneven and insuf ficient across regions,re flecting the progress and shortfalls in China’s efforts to promote balanced development.Our findings provide implications for how policymakers may help people’s expectations for a better life materialize by spurring balanced economic,social,environmental and livelihood development across regions. 展开更多
关键词 Balanced Development Index principal social contradictions needs for a better life imbalanced and inadequate development
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Solutions for Sustainable Economic Development inHo Chi Minh City 认领
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作者 Bui Ngoc Hien 《管理研究:英文版》 2020年第1期74-83,共10页
Sustainable urban development is becoming the top concern of the nations in making and implementing the development policy systems.Sustainable urban development is a harmonious,effective development process with three... Sustainable urban development is becoming the top concern of the nations in making and implementing the development policy systems.Sustainable urban development is a harmonious,effective development process with three pillars:economic development,social inclusion,and environmental management effectively.Vietnam is a rapidly urbanizing country.This process makes Vietnam’s cities face many major problems and challenges,especially sustainable economic development.Ho Chi Minh City is Vietnam’s largest city.It is the dynamic city with the fastest socio-economic development rate of Vietnam.The development of Ho Chi Minh City plays an important role in the overall development of the whole country.However,in the assessments of the authorities and experts,Ho Chi Minh City is growing slowly and facing many big problems.Based on the analysis of the City’s potentials and advantages as well as the difficulties and challenges of the new development context,this paper recommends groups of solutions for sustainable economic development in Ho Chi Minh City in the next decades. 展开更多
关键词 SUSTAINABLE urban DEVELOPMENT SUSTAINABLE ECONOMIC DEVELOPMENT HO CHI Minh CITY
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Dynamical Control of Asymmetrically Oblique Tidal Currents to the Sedimentary Characteristics and Development of Linear Sand Ridges in the Liaodong Shoal, East Bohai Sea 认领
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作者 ZHANG Lianjie ZHU Longhai +3 位作者 WU Jianzheng HU Rijun WANG Peng ZHANG Pan 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2020年第1期101-112,共12页
The Liaodong Shoal is a group of linear sand ridges located in the east Bohai Sea of China.In this study,54 surface sediment samples have been collected,current measurements at 4 stations have been carried out and bat... The Liaodong Shoal is a group of linear sand ridges located in the east Bohai Sea of China.In this study,54 surface sediment samples have been collected,current measurements at 4 stations have been carried out and bathymetric data were obtained.The current directions are rightward deflected relative to the strikes of the sand ridges.Affected by the narrowing effect of the ridge,the current velocities exhibited an anti-‘C’type vertical profile.The velocities of the lower currents linearly correlate with the water depths.The near-bed current velocities over the troughs are estimated to be higher than those over the ridges,and this feature could be explained by the loss of kinetic energy together with the conversion between kinetic energy and gravitational potential energy.The sedimentary characteristics that are compatible with the tidal dynamics are developed across the ridges and troughs,including grain size compositions,grain size parameters,mineral compositions and Dhm indexes.The existence of the angles between the current directions and the strikes of the sand ridges is the key factor for the growth of the sand ridges.The asymmetric hydrodynamic features between the flood and ebb currents lead to the differences in the topographical and sedimentary characteristics on both sides of a sand ridge.Insufficient material supply led to the degradation of the sand ridges,and the reduction of the tidal current intensity has led to the development of the subordinate sand ridges in the troughs.Sand ridges are migrating. 展开更多
关键词 LIAODONG SHOAL tidal current RIDGE heavy minerals sedimentary characteristic DEVELOPMENT and evolution
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清末民初湖南图书馆的创建与发展(1904-1919) 认领
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作者 王蓉 《齐齐哈尔师范高等专科学校学报》 2020年第1期97-99,共3页
鸦片战争后,西方“图书馆”思想传入我国,掀起一股兴办图书馆的热潮。1904年,湖南图书馆兼教育博物馆开馆,次年更名为“湖南图书馆”。其以“保存国粹,输入文明,开通智识”为宗旨,开中国图书馆事业之先河,其后逐渐步入正轨。然而,民国... 鸦片战争后,西方“图书馆”思想传入我国,掀起一股兴办图书馆的热潮。1904年,湖南图书馆兼教育博物馆开馆,次年更名为“湖南图书馆”。其以“保存国粹,输入文明,开通智识”为宗旨,开中国图书馆事业之先河,其后逐渐步入正轨。然而,民国初期社会动荡,政治干预文化,湖南图书馆的局限性暴露无遗,但其作为社会教育的一次有效尝试并发展至今,从办馆理念到馆舍建设、制度管理、读者服务等方面都具有非凡的意义,极大推动了我国图书馆事业的发展。 展开更多
关键词 清末民初 湖南图书馆 创建 发展
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我国大型铸锻件行业发展回顾与展望 认领
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作者 李骏骋 《大型铸锻件》 2020年第3期1-4,11共5页
总结和回顾了我国大型铸锻件行业在生产能力、极限制造技术、产品结构调整、科技创新方面取得的成就,分析了行业面临的发展形势和挑战,对行业未来发展提出了建议。
关键词 大型铸锻件 行业 发展 总结
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浅谈汉元素在现代服装中的应用与发展 认领
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作者 王一如 苏悦 王依乐 《纺织报告》 2020年第2期111-112,共2页
汉服是中华文化的一个重要载体,有着悠久的历史和深厚的文化底蕴,在社会的不断变迁和发展下,汉元素成为一种新型的时尚潮流。在遵循传统文化的前提下,汉元素的分解与重组可以将传统的服装元素融合到现代服装中。以汉元素的复兴为依据,... 汉服是中华文化的一个重要载体,有着悠久的历史和深厚的文化底蕴,在社会的不断变迁和发展下,汉元素成为一种新型的时尚潮流。在遵循传统文化的前提下,汉元素的分解与重组可以将传统的服装元素融合到现代服装中。以汉元素的复兴为依据,传承传统文化的过程中也是探索汉元素在现代服装中全新的发展领域和未来道路。 展开更多
关键词 汉元素 汉服文化 现代服装 应用 发展
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阳山鸡出生后早期左卵巢组织结构发育的变化 认领
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作者 罗来福 郑淑欣 +3 位作者 刘为民 赵海全 张晖 叶亚琼 《解剖学杂志》 CAS 2020年第1期26-30,共5页
目的:观察阳山鸡卵巢生后早期发育。方法:采用常规组织学方法,比较1~7 d龄阳山鸡左卵巢组织结构的发育变化过程。结果:出生时双侧卵巢已经显示左右明显的不对称,右侧卵巢于5 d龄开始退化,而左侧卵巢持续发育,形状为扁椭圆形,分为2叶;颜... 目的:观察阳山鸡卵巢生后早期发育。方法:采用常规组织学方法,比较1~7 d龄阳山鸡左卵巢组织结构的发育变化过程。结果:出生时双侧卵巢已经显示左右明显的不对称,右侧卵巢于5 d龄开始退化,而左侧卵巢持续发育,形状为扁椭圆形,分为2叶;颜色为灰白色。切片观察可见,出生时鸡左侧卵巢实质由皮质、外髓质和内髓质构成。皮质主要由处于减数分裂前期的卵母细胞构成,3 d龄时卵母细胞的染色体进一步凝缩;5 d龄时皮质的卵母细胞全部消失,外髓质已开始有成形的卵泡出现;大约7 d龄时,外髓质的卵泡大而清晰,皮质几乎完全消失,外髓质最终成为真正的皮质。结论:在生后1周内,阳山鸡左卵巢皮质发生明显衰退、崩解和丢失,外髓质最终成为真正的皮质。 展开更多
关键词 阳山鸡 卵巢 发育 皮质 孵化后
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Looking Back on 2019 认领
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《中国对外贸易:英文版》 2020年第1期2-13,共12页
The last 12 months mark a historic 2019 for China.With innovation continuing to power the world’s second largest economy,China has made countless advances.In April,Beijing played host to two international events that... The last 12 months mark a historic 2019 for China.With innovation continuing to power the world’s second largest economy,China has made countless advances.In April,Beijing played host to two international events that focused on two different but interdependent elements of development. 展开更多
关键词 China. development. CONTINUING
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商周球铃装饰的起源与流向 认领
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作者 韩金秋 杨丙君 《中原文物》 北大核心 2020年第1期96-101,共6页
本文探讨了商周时期球铃装饰的起源和流向,从发生动因、社会背景、参考原型等三个方面讨论了球铃装饰的起源,并指出在东周时期,球铃装饰衰落,球铃转而成为一种独立的装饰品,用来缝缀在服饰上。
关键词 商周 球铃装饰 来源 流向
海洋侧扫声呐探测技术的现状及发展 认领
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作者 何勇光 《工程建设与设计》 2020年第4期275-276,共2页
海洋侧扫声呐探测技术是探测海洋底部形貌的一种主要技术手段,具有经济效益高、分辨率高的特点,经常应用于近岸海洋工程测量、港口河道测量等工作中,同时也能够对海底的沉船、礁石、电缆、管道以及其他水下目标等进行有效的探测。基于此... 海洋侧扫声呐探测技术是探测海洋底部形貌的一种主要技术手段,具有经济效益高、分辨率高的特点,经常应用于近岸海洋工程测量、港口河道测量等工作中,同时也能够对海底的沉船、礁石、电缆、管道以及其他水下目标等进行有效的探测。基于此,论文主要对海洋侧扫声呐探测技术的测扫声呐结构和原理进行简单的介绍,分析现阶段国内外侧扫声呐的发展现状,最后展望海洋侧扫声呐的未来发展趋势,希望能够为相关人士提供帮助。 展开更多
关键词 海洋探测 侧扫声呐探测技术 现状 发展
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基桩反射波理论和测试方法的发展与其核心思路 认领
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作者 荣垂强 《工程质量》 2020年第4期78-80,85,共4页
基桩低应变测试的理论基础是一维纵波理论,该理论简单易懂且已被广泛接受,但因无法解释三维条件下产生的高频三维干扰信号而将其误判为缺陷信号。现阶段,基桩三维理论主要从波场和振动两个角度研究并解释了三维干扰信号的成因,进而提出... 基桩低应变测试的理论基础是一维纵波理论,该理论简单易懂且已被广泛接受,但因无法解释三维条件下产生的高频三维干扰信号而将其误判为缺陷信号。现阶段,基桩三维理论主要从波场和振动两个角度研究并解释了三维干扰信号的成因,进而提出了单点采样法和双速度采样法,它们可以实现在采样阶段便能较好地消除三维干扰信号而主要保留纵波信号,从而达到继续使用一维理论的目的。 展开更多
关键词 基桩反射波法 理论 采样方法 发展 核心思路
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