长江航道三维可视化系统设计与实现          下载免费PDF全文

张建春 《海洋测绘》2017,(3):66-69

为满足航道工程的信息化和可视化需求,采用VPB和OSG相结合的引擎进行长江航道三维可视化系统开发,并从开发平台选取、可视化系统的结构和功能设计、多源数据获取与处理等多个方面,阐述了设计与实现的关键环节,取得了较好的三维可视化效果,研究技术路线将为海洋与内河航道场景三维可视化系统研发提供重要参考。  相似文献   

基于孔喉结构建立致密砂岩储层评价方案——以松南中央坳陷泉四段为例     

蔡来星  卢双舫  张训华  肖国林  吴志强  黄文彪 《吉林大学学报(地球科学版)》2017,(6):1654-1667

致密砂岩储层评价方案是识别储层"甜点"的基础,也是致密油勘探的重点和难点,但目前国内对此尚无统一认识。为此,以松南中央坳陷区泉四段致密砂岩为例,综合常规压汞、恒速压汞、高压压汞等多种资料对致密储层微观孔喉结构进行了精细表征,并以此为基础建立了致密砂岩储层评价方案。结果表明:研究区致密砂岩孔喉小、物性差,储集空间以次生溶孔为主;储层渗透性主要由占小部分体积的最大孔喉半径所控制,喉道半径越大、大喉道所占比例越高,致密储层的渗透率(K)就越高、品质就越好。在此基础上,由孔喉结构的差异性出发,将松南中央坳陷区泉四段致密砂岩储层分类4类,其中,石油能够充注至Ⅰ—Ⅲ类致密储层,且Ⅰ类致密储层(K为(0.1~1.0)×10~(-3)μm~2)品质最高,可视为储层"甜点"。  相似文献   

The changes of pigment contents and their environmental implications in the lake sediments of Ny-(A)lesund, Svalbard, the Arctic     

姜珊  刘晓东  徐利强  孙立广 《极地研究(英文版)》2010,21(1):60-70

According to palaeoclimatic and modern instrumental data, numerous studies have indicated that the Arctic climate has undergone a significant warming during the past 100 years, and this may lead to significant impact on the fragile lake ecosystem. In this study, we collected a lake sediment core from the Ny-(A)lesund of Svalbard and determined the concentrations of four pigments including chlorophyll derivatives, total carotenoids, oscillaxanthin and myxoxanthophyll in the sediments. Combined with other physical and chemical proxies such as calcium carbonate, total organic carbon, biogenic silicon etc., we have reconstructed the historical changes of lacustrine primary productivity in Ny-(A)lesund, especially for the past 100 years. The results showed that during the period of Little Ice Age (LIA), the climate was unfavorable for the growth of the lake algae, and thus the lacustrine productivity declined. This result was supported by the relatively low contents of pigment and biogenic silica in the sediments. In contrast, the contents of total organic carbon (TOC) and sediment pigments increased significantly in the upper 5 cm (~1890AD), reflecting the rapid growth of the lake algae, thus the great increase of lacustrine primary productivity, corresponding to the warming climate after LIA. However, the biogenic silica in the upper sediments still had a relatively low level, and this might be related to the growth competition with other algae species. Over the past 100 years, the ratio of Osc/Myx in the sediments decreased continuously, indicative of durative increase of myxoxanthophyll in blue-green algal pigments, and this might imply that the human activity had enhanced the nutrition level of the lake in the Arctic region.  相似文献   

A coupled regional Arctic sea ice-ocean model: configuration and application     

李群  张璐  吴辉碇 《极地研究(英文版)》2010,21(2):180-192

A regional sea ice-ocean coupled model for the Arctic Ocean was developed, based on the MITgcm ocean circulation model and classical Hibler79 type two categorythermodynamics-dynamics sea ice model. The sea ice dynamics and thermodynamicswere considered based on Viscous-Plastic (VP) and Winton three-layer models, respectively. A detailed configuration of coupled model has been introduced. Special attention has been paid to the model grid setup, subgrid paramerization, ice-ocean coupling and open boundary treatment. The coupled model was then applied and two test run examples were presented. The first model run was a climatology simulation with 10 years (1992?002) averaged NCAR/NCEP reanalysis data as atmospheric forcing. The second model run was a seasonal simulation for the period of 1992?007. The atmospheric forcing was daily NCAR/NCEP reanalysis. The climatology simulation captured the general pattern of the sea ice thickness distribution of the Arctic, i.e., the thickest sea ice is situated around the CanadaArchipelago and the north coast of the Greenland. For the second model run, themodeled September Sea ice extent anomaly from 1992?007 was highly correlated with the observations, with a linear correlation coefficient of 0.88. Theminimum of the Arctic sea ice area in the September of 2007 was unprecedented. The modeled sea ice area and extent for this minimum was overestimated relative to the observations. However, it captured the general pattern of the sea ice retreat.  相似文献   

学习《廉政准则》争做廉政楷模——贯彻落实《中国共产党党员领导干部廉洁从政若干准则》学习体会集锦     

《黑龙江国土资源》2010,(4):27-34

一、用心学习,在思想认识上求深 《廉政准则》有三个突出特点。一是党中央对党员领导干部廉洁从政的关注日益突显。针对新形势、新情况、新问题,修改和完善的《廉政准则》,作为正式的党内法规予以施行,表明党中央对廉洁从政的重视已经上升为事关党和国家生死存亡的战略高度。二是依靠制度反腐的方向更加明确。中央正在积极构建形成用制度规范从政行为、按制度办事、靠制度管人的新机制,教育、监督、  相似文献   

强令央企退市是因噎废食     

吴其伦 《国土资源导刊(湖南)》2010,7(4):53-54

<正>在笔者看来,国资委此举纯属无奈,从这一事件的因果关系来看,央企退出房地产是国有经济体的悲哀。3月18日,国资委召开新闻发布会,公布了央企地产业务的具体情况。国资  相似文献   

两个宣言验证中国     

倪艳 《地球》2010,(1):40-43

2009年11月17日至21日,江西省委、省政府以首届“世界低碳与生态经济大会暨技术博览会”的召开为契机,竭诚邀请中央企业共商扩大战略合作大计,促进央企和江西省企业优势互补．携手合作、共同发展。站在全局的高度,江西省这个革命老区以战略的思维和长远的眼光采认识低碳经济,紧紧抓住世界产业转移、企业重组、结构调整的机遇,按照在全国范围内推进国有资产、资源的优化重组的战略要求,  相似文献   

地磁变化之探     

王国方 《地球》2010,(5):69-69

近日,美国《科学》杂志的一篇文章报道：近150年来,地球南北极磁场正在急剧地衰减,如果这种衰减持续下去,地球磁场可能在下个千年的某个时期消失。但更多的专家认为,地磁场并不会真正消失,地球磁场的衰减只是地球南北两个磁极倒转中的过渡而已。  相似文献   

秋季北极海冰与欧亚冬季气温在年代际和年际尺度上的不同联系          下载免费PDF全文

何金海  武丰民  祁莉 《地球物理学报》2015,58(4):1089-1102

北极海冰的急剧消融在近年来欧亚大陆频发的低温事件中扮演着关键角色.秋季北极海冰的偏少对应着冬季欧亚大陆的低温天气,然而二者的联系在年代际和年际两种时间尺度上存在显著区别.本文运用1979—2012年哈德莱中心第一套海冰覆盖率(HadISST1)、欧洲中心(ERA_Interim)的2m温度、风场、海平面气压场、高度场等资料,分别研究了年代际和年际时间尺度上前期秋季北极海冰与欧亚冬季气温的联系.结果表明,欧亚和北极地区(0°—160°E,15°N—90°N)的冬季气温具有显著的年代际和年际变化.在年代际尺度上,温度异常分布在21世纪初由北极冷-大陆暖转为北极暖-大陆冷.这一年代际转折与前期秋季整个北极地区的海冰年代际减少联系密切.秋季北极全区海冰年代际偏少对应冬季欧亚大陆中高纬地区的高压异常,有利于北大西洋的暖湿气流北上和北极的冷空气南侵,造成北极暖-大陆冷的温度分布;在年际时间尺度上,温度异常分布主要由第一模态的年际变化部分和第二模态组成,且第一模态包含的年际变率信号也存在显著的年代际变化.年际尺度上全区北极海冰对欧亚冬季气温的影响远不及位于北冰洋西南边缘的巴伦支海、喀拉海和拉普捷夫海西部(30°E—120°E,75°N—85°N)的关键区海冰影响显著.关键区内海冰的偏少会引发冬季的北大西洋涛动负位相,导致北大西洋吹往欧亚大陆的暖湿气流减弱和欧亚大陆中高纬地区的气温偏低.  相似文献   

长江干线北斗CORS建设的若干思考     

张国平 《测绘通报》2015,(7):5

从CORS技术发展现状和长江经济带发展战略、国家空间信息安全等角度论述了长江干线北斗CORS建设发展的必要性和战略意义,并进一步论述了长江干线北斗CORS的建设原则、关键点,以及对应用规划的发展建议。长江干线北斗CORS建设应引起相关部门的高度重视,建议尽快将建设纳入规划,并研究立项和实施等相关事宜,顺应国家依托黄金水道建设长江经济带的国家战略,并加强长江干线北斗CORS的推广应用,支援沿江经济建设和社会发展,全面推动测绘技术和经济发展的转型升级。  相似文献