20个激变变星或相关天体的分光证认   总被引：1，自引：0，他引：1  

李宗云  刘武 《天文学报》1999,40(1):1-15

在２０个研究得很少的激变变星或者曾经被分类为激变变星的相关天体的光谱中,１３个被证实为属于激变变星（６５％）,另外７个似乎应该被排除（表１第８列）,不像其他研究者那样,仅给出非激变变星或热天体,还以更强的证据和更多的光谱特征征认出１个ＤＡ型白矮星,４个双星系统及其子星的光谱型。新的光谱资料不支持ＦＹ Ｐｅｒ的Ｈｅｒｂｉｇ Ａｅ／Ｂｅ分类,它是一个激变变星。对于ＰＧ１７１２＋４９３,不仅给出星和云的  相似文献   

小波多尺度分析在煤厚探测中的应用     

于师建王宗胜  刘延欣 《煤田地质与勘探》2005,33(5):70-72

根据声波反射法探测顶煤厚度中存在的问题,提出了将小波多尺度分析应用到实际煤厚探测信号分析中的信号处理方法。结果表明:小波多尺度分析大大改善了煤层顶板弱反射波的识别能力,提高了煤厚探测的精度。   相似文献   

2002～2003年南极中山站地区风要素变化特征   总被引：5，自引：1，他引：4  

许淙  万军  吕非 《海洋预报》2004,21(4):28-34

利用2002年1月至2003年12月南极中山站24个月的天气观测记录和天气形势图,对中山站地区的风要素特征进行了天气学分析研究,本文较详细地分析了该地区的风向,风速的分布特征以及风向与风速相互间的变化规律,确定了不同季节的盛行风向,初步探讨了风要素变化与大气环流的关系。所得结论对了解该地区的天气变化特点,提高天气预报的准确率以及对中山站发展设计规划的制定都有重要的参考价值。  相似文献   

基于室内路网的跨楼层路径规划技术的设计与实现     

钟耳顺  宋关福  李绍俊  蔡文文  左尧  李少杰  黄科佳 《地理信息世界》2018,(3):91-95

随着室内定位技术、BIM-GIS技术和室内地图研究的发展,室内位置服务需求日益旺盛。作为室内位置服务的关键技术之一,室内路径规划成为研究与应用热点。但是早先的路径规划技术往往基于单层网络拓扑模型而设计,由于模型缺少楼层之间的连通信息,而不能实现跨楼层导航算法分析;而后随着跨楼层导航算法的出现,跨楼层的路径规划、导航及定位得以实现,但这些跨楼层导航算法基于楼层连接通达规则,往往需要多次遍历楼层信息,运算效率低下。针对这一问题,本文利用电梯、扶梯、楼梯等楼层间连接信息,设计、实现了基于楼层连接表的室内多层路网分析模型,并采用逐层分析的方法和多次网络分析,实现室内跨楼层的带有多个途经点路径分析。整个技术框架包括跨楼层路网生成模块、位置点接收模块、网络分析模块、循环控制模块。算法方面,本研究采用双向遍历的A*最短路径分析算法,通过网络路径分析,最终将满足约束条件的规划路径显示在移动设备上,帮助用户实现跨楼层、多途经点的定位与路径导航。  相似文献   

Coupled Responses of Sewol, Twin Barges and Slings During Salvage     

YAO Zong  WANG Wei-ping  JIANG Yan  CHEN Shi-hai 《海洋工程》2018,32(2):226-235

Korean Sewol is successfully lifted up with the strand jack system based on twin barges. During the salvage operation, two barges and Sewol encounter offshore environmental conditions of wave, current and wind. It is inevitable that the relative motions among the three bodies are coupled with the sling tensions, which may cause big dynamic loads for the lifting system. During the project engineering phase and the site operation, it is necessary to build up a simulation model that can precisely generate the coupled responses in order to define a suitable weather window and monitor risks for the salvage operation. A special method for calculating multibody coupled responses is introduced into Sewol salvage project. Each body’s hydrodynamic force and moment in multibody configuration is calculated in the way that one body is treated as freely moving in space, while other bodies are set as fixed globally. The hydrodynamic force and moment are then applied into a numerical simulation model with some calibration coefficients being inserted. These coefficients are calibrated with the model test results. The simulation model built up this way can predict coupled responses with the similar accuracy as the model test and full scale measurement, and particularly generate multibody shielding effects. Site measured responses and the responses only resulted from from the simulation keep project management simultaneously to judge risks of each salvage stage, which are important for success of Sewol salvage.  相似文献   

气象服务需求的理论研究     

黄宗捷  张碧 《成都信息工程学院学报》1999,(3)

气象服务需求是气象经济学中亟待深入研究的问题。从经济学的需求意义上,立足于气象服务实践,提出气象服务需求主体与需求客体,进而把需求主体划分为政府和企业,把需求客体划分为公共产品和服务商品。并在此基础上,重点剖析制约公共气象服务产品的需求因素和制约气象商品的需求因素  相似文献   

Numerical analysis of the forces exerted on offshore structures by ship waves     

G.H. Dong  L. Sun  Z. Zong  Y.P. Zhao 《Ocean Engineering》2009,36(6-7):468-476

Ship-generated waves can contribute to the fatigue of offshore structures. This paper presents a numerical model for evaluating the forces exerted on a nearby fixed structure by ship-generated waves. The ship waves were modeled using Michell's thin-ship theory (Wigley waves), and the forces were computed using a boundary element method in the time domain. The simulation was validated by comparing its results with those of frequency-domain methods reported in the literature. It was then applied to calculate the forces exerted on a hemisphere by ship waves varying with the ship's speed, dimensions and distance from the hemisphere to the ship's path. Our results indicate that the ship waves have enormous effects on offshore structures and are not neglectable.  相似文献   

Interannual variability of SST,SLA and wind waves in the Hawaii area and their responses to ENSO     

Yongcun Cheng  Qing Xu  Yuguang Liu  Chongyin Li  Zengzui Rong  Haibo Zong  Xiu Peng  Xiaobin Yin 《中国海洋大学学报(英文版)》2008,7(4):379-384

Time series of sea surface temperature (SST),wind speed and significant wave height (SWH) from meteorologicalbuoys of the National Data Buoy Center (NDBC) are useful for studying the interannual variability and trend of these quantities at the buoy areas.The measurements from 4 buoys (B51001,B51002,B51003 and B51004) in the Hawaii area are used to study theresponses of the quantities to EI Nino and Southern Oscillation (ENSO).Long-term averages of these data reflect precise seasonaland climatological characteristics of SST,wind speed and SWH around the Hawaii area.Buoy observations from B51001 suggest asignificant warming trend which is,however,not very clear from the other three buoys.Compared with the variability of SST andSWH,the wind speeds from the buoy observations show an increasing trend.The impacts of El Nifio on SST and wind waves arealso shown.Sea level data observed by altimeter during October 1992 to September 2006 are analyzed to investigate the variabilityof sea level in the Hawaii area.The results also show an increasing trend in sea level anomaly (SLA).The low-passed SLA in theHawaii area is consistent with the inverse phase of the low-passed Sol (Southern Oscillation Index).Compared with the low-passedSOl and PDO (Pacific Decadal Oscillation),the low-passed PNA (Pacific-North America Index) has a better correlation with thelow-passed SLA in the Hawaii area.  相似文献   

徐州煤矿地质资料数据库建设及应用     

钱静  纵博  黄阳 《江苏地质》2023,47(2):159-165

通过对徐州煤矿地质资料的标准化整理，归纳并探讨多源数据融合的原则和标准，形成统一的空间坐标参数和数据格式，达到多源数据统一融合的目的。基于ArcGIS平台，建立涵盖基础地质、矿山开发利用、钻孔、采空区、塌陷及已治理区5大专题的煤矿地质资料数据库。项目成果纳入徐州自然资源“一张图”系统中，服务于矿政管理、矿地融合研究、工程建设新项目规划选址、国土空间规划等工作。  相似文献   

大部地区降水偏多冷空气活动频繁-2000年1O月-     

宗志平 《气象》2001,27(1)

10月份，全国大部地区降水量偏多，海南等省的一些地区发生暴雨洪涝灾害；气温接近常年，月内气温起伏较大；南方连阴雨日数多，日照时数偏少。长时间的阴雨寡照给我国秋收、秋种带来不利影响。气温变幅较大华南出现寒露风连阴雨时间长秋收秋播受影响  相似文献