节理扩展煤层应力场的联合反演分析

考虑地应力作用下节理扩展引起的煤岩物理力学性质改变,进而导致煤层应力、变形的重新分布,给出了煤岩单元节理扩展的计算方法,并分析了节理扩展与应力的相互作用关系。应用小波神经网络方法及逐级加载算法,提出节理扩展煤储层应力场的联合反演方法,并对沁水盆地晋城区块煤储层应力场分布规律进行分析。结果表明：晋城区块最大主应力为8～13 MPa,由西北向东南呈逐渐增大趋势;最小主应力为5～9 MPa,应力低值区集中在晋城南部区域。通过对比关键点的现场实测值与模拟计算结果,得知主应力大小与实测值最大误差仅为3%,方位误差小于1.3°,满足工程计算精度要求。利用联合反演分析煤储层应力场,具有计算精度高、速度快、建模简单等优点,适合于软件集成快速计算。     

Ecological footprint and vulnerability of marine capture fisheries in China

China(herein referred as China’s mainland,and excluding Hong Kong,Macao and Taiwan)ranks as the world’s leading fishing nation,with approximately 11.1 million tons of domestic marine catch acquired in 2017.Marine fisheries resources in China are mainly exploited by its 11 coastal provinces and municipalities,and the development of fishing industry varies among them.However,few studies have examined the exploitation history of the 11 coastal provinces and municipalities.In this paper,we systematically quantified the exploitation history of marine fishery resources in China and then measured the vulnerability of the 11 coastal provinces and municipalities of China to a reduction in marine catches.Our analysis suggested that Chinese marine fisheries experienced rapid growth from the mid-1980 s to the end of the 20 th century,and this rapid increase in marine catches were mainly promoted by increased fishing effort.The total primary production required level amounted to approximately 80%of the average primary productivity in 2017,and Zhejiang,Fujian,Shandong,Hainan and Guangdong provinces were the main fishing provinces in China.By assessing three dimensions of vulnerability(exposure,sensitivity and adaptive capacity)to the impacts of a reduction in marine catches in the 11 coastal provinces and municipalities,we found that Hainan,Guangxi,Zhejiang and Fujian provinces had high or very high vulnerability,while the municipalities of Shanghai and Tianjin had low vulnerability.Identifying suitable adaptation policies and management plans based on the differences in vulnerability among coastal provinces is important in sustainable fisheries management.     

Three-stage tectonic subsidence and its implications for the evolution of conjugate margins of the southwest subbasin,South China Sea

To reveal the tectonic characteristics of the continental margins in the southwest subbasin (SWB) of the South China Sea, a long high-resolution seismic profile...     

烟台市船舶与海工装备产业高质量发展研究

为促进烟台市船舶与海工装备产业的发展,文章基于其发展现状,分析其高质量发展的总体思路、空间布局和攻坚方向,并提出政策建议。研究结果表明：目前烟台市船舶与海工装备产业发展空间快速拓展、市场主体规模不断扩大、“双创”平台体系化发展、产业规模和层级稳步提升,但仍存在产业发展层级较低、创新支撑能力整体较弱、人才队伍建设亟须加强...     

渤海经济无脊椎动物群落的年代变动

With the decline of fish stocks, the proportions of economically important invertebrates like crustaceans and cephalopods have increased in the Bohai Sea. The community structure and trophic level of economically important invertebrates were analyzed using the bottom trawl survey data collected by the Yellow Sea Fisheries Research Institute in the Bohai Sea in May and August of 1958–1959, 1982, 1992–1993, 2004, 2009 and 2015. A total of 37 species of economically important invertebrates, belonging to 5 orders, 24 families, were captured. The biomass densities of economically important invertebrates in the Bohai Sea displayed an overall downward trend from 1982 to 2015. Oratosquilla oratoria and Loligo spp. were the most dominant species in the past 30 years, the biomass proportion of O. oratoria increased gradually in both May and August from 1982 to 2015. Moreover,biodiversity indices of economically important invertebrates in the Bohai Sea appeared to decline from 1982 to2004 and then increased in 2015. Similarly, the mean trophic level of economically important invertebrates declined from 1982 to 2004 and increased slightly in 2015. Overall, although the proportions of invertebrates have increased, the biomass densities in the Bohai Sea have displayed an overall downward trend from 1982 to 2015.The increases in the biodiversity and trophic level of economically important invertebrates after the 2000 s,possibly benefit from stock enhancement projects implemented by governments at different levels and national fishery management measures such as the "double-control" of the total number and engine power of fishing vessels and summer moratorium of fishing.     

透水与隔水夹层对粉质土液化影响试验研究

黄河三角洲沉积物以粉质土为主,循环荷载作用下隔水夹层与透水夹层的存在对粉质土孔压累积、消散及液化的影响如何,目前尚不清楚。本文针对4种隔水夹层与透水夹层的组合情况,利用现场原位振动和室内土样振动试验,研究隔水夹层与透水夹层的存在对循环荷载作用下黄河口粉质海床土液化过程影响,发现循环荷载导致黄河三角洲粉质土孔隙水压力、粒度成分、密度、含水量及孔隙比等物性指标发生的变化,因夹层的不同有明显的差异,并且其液化性能因夹层结构的不同而不同,有透水夹层时,相对提高了粉土的抗液化性能,隔水夹层则相反。     

雷达波偏移方法研究

为了解决由于点状体的绕射和倾斜界面造成的失真现象,本文从探地雷达偏移处理的基本原理出发,分别介绍了以射线理论为基础的绕射扫描偏移和以波动方程为出发点的克希霍夫积分偏移、有限差分偏移以及有限元偏移．随着计算机的高速发展,运算速度得到了明显提高,目前,以波动方程为基础的偏移方法逐渐占据了主导地位,由于它的高精度等很多优点受到了人们的欢迎．总结了各种偏移方法的优缺点和适用范围,为探地雷达进一步的偏移研究奠定了理论基础．     

地震波形数据处理软件研发

通过分析地震数据EDAS Event格式与SEED格式在文件头与数据部分存储的特点与规律,利用Visual Basic语言研发地震波形数据处理软件.利用此软件,可以完成地震记录数据的格式转换,以及数据的抽取与合并,保证数据记录的连续与衔接,提高数据的连续性和利用价值.     

中国海洋生物研究70年

随着中国“海洋强国”战略的提出,加快建设海洋类学科的发展成为历史必然,海洋生物是海洋不可分割的一部分,海洋环境和生物相互依存,相互作用,海洋生物研究重要性日益凸显。为纪念中国科学家在海洋生物领域的突出贡献,本文回顾了建国以来中国海洋生物相关的重要研究进展,梳理了中国科学家在海洋生物领域的突出贡献,系统总结并讨论了未来研究方向,抛砖引玉,希望籍此助推中国海洋生物研究的新高潮。