水库重力测量检测非牛顿引力的实验数据分析新方法     

汪汉胜  朱灼文  潘显章  仲伟亚 《大地测量与地球动力学》1993,(4)

本文提出水库重力测量检测非牛顿引力的实验数据分析新方法。利用近一天两重力仪的重力差值信号,基于同液面高度变化水体重力信号相等这一具有明显物理意义的准则,建立仪器零漂信号多项式系数矢量的矩阵方程,通过极大似然反演比较严格地计算漂移信号,并从中提取检测信号。实例计算结果表明:(1)当数据充分、漂移多项式阶数取值适当时,该方法完全有效;(2)在现有水库实验的设备和技术条件下,测定万有引力常数G对实验室值的偏离精度可达0.15％,优于矿井实验和先前水库实验的分析结果;若进一步改善水面高度测量,检测精度还可明显提高;(3)Hornberg水库实验重力仪G709在0.4％的精度范围内,未发现G对实验室值的偏离。  相似文献   

The Forming Conditions of and Ore-searching Direction for B, Mg,Pb, Zn and Au Deposits in the Liaoji Proterozoic Rift     

Zhu Yongzheng  Yao Fengliang 《东北亚地学研究》2001,(1)

The Proterozoic was the first of severa1 impor-tant transitional periods in the earth's evolutionaryhistory. Linear .rifts over1apped on the b4se ofArchean granite -- greenstone and high -- grade gneissregimes. Along with the formation and evolution ofthe…  相似文献   

FIRST RECORD OF AN EYE DISEASE IN THE BOWHEAD WHALE (BALAENA MYSTICETUS)     

祝茜 《中国海洋湖沼学报》1997,15(2):192-192

Bowheadwhale(Balaenamysticetus)isahighlyvaluedspecies,andofimportancetotheAlaskancoastEskimoswhoharvestitastheirtraditionalfoodresource.Itisknownastheicewhalebecauseitspendsmuchofitslifeintheice.ItwassurprisingtofindacaseofeyediseaseintheeyespecimensfromthebowheadwhalesharvestedinthecoldenvironmentatBarrow,Alaska,USA.Somebasicinformationispasentedbelow.Bowheadwhale96B14washarvestedbywhalingcaptainJacobAdamsonSeptember16,1996.ThisWhalewasafemalewithbodylengthof8.33m.Thecorneaofbotheyeswas…  相似文献   

南大洋氟的生物地球化学研究——Ⅰ.南极磷虾富氟异常的研究          下载免费PDF全文

张海生  夏卫平  程先豪  朱碧英 《极地研究》1991,3(4):24-30

本文通过对南极磷虾不同部位中氟含量的测定,结合氟在测区环境中的分布特征及南极磷虾体中其它元素的分析资料,讨论了氟在磷虾体内的分布和赋存形式,并对其可能的富集机理及与环境的关系作了初步的探讨。  相似文献   

SEA LEVEL RISE OF THE ZHUJIANG RIVER DELTA AND NEOTECTONICS     

曾昭璇  刘南威  胡男  丘世钧  黄山  李平日  方国祥  黄光庆  祝功武 《中国地理科学(英文版)》1993,3(1):44-50

A linear regression analysis of 28 selected tide-gauge stations of the Zhujiang Estuary shows that there has been a tendency of local sea level rise at a rate of 2.028 mm per year. The origin of the variation is significantly attributed to the local tectonic movement of discrepant fault-block. Based on this, four types of relative local sea level changes are classified. According to calculation, half of the fertile land, or 800 km2 of the delta plain will have been submerged by sea water by about 2040. This will yield a significant influence on the economic construction and human activities.  相似文献   

first record of an eye disease in the bowhead whale ( Balaena mysticetus )     

Zhu Qian 《中国海洋湖沼学报》1997,15(2):192

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A Study on the Meat and Bone Meal or Poultry By-product Meal as Protein Substitutes of Fishmeal in Concentrated Diets for Paralichthys olivaceus   总被引：2，自引：0，他引：2  

ZHU Wei MAI Kangsen ZHANG Baigang HU Yangjiang YU Yu 《中国海洋大学学报(英文版)》2006,5(1):63-66

A study was conducted to evaluate the effects of meat and bone meal （MBM） and poultry by-product meal （PBM） as the replacement of fishmeal in the diets on the growth performance, survival and apparent digestibility coefficient （ADC） of Japanese flounder （Paralichthys olivaceus）. The experimental diets included 0%, 20%, 40%, 60% and 80% MBM or PBM replacement of total fishmeal respectively. All diets were iso-nitrogenous and isocaloric. The results showed that there are no significant differences （P 〉0.05） in growth performance among the treatments fed with 0% -60% MBM replacement of fishmeal, while the percent weight gain （WG, % ）, body length gain （BLG, % ） and ADC significantly decrease when fishmeal is replaced by 80% MBM. The result showed also that there are no significant differences （P 〉0.05） in growth performance and ADC among all treatments fed with the diets with 0% -80% replacements of fishmeal with PBM.  相似文献   

青田芝溪头鹤溪群浅变质岩系中发现动物化石     

朱德寿  胡耀华  石关根 《浙江国土资源》1994,(2)

作者于1993年4月在浙江青田芝溪头鹤溪群剖面上采集了白云质大理岩标本样品，送南京地质古生物研究所进行标本浸泡处理。首次获得鱼骨、管状化石及土菱子介等海相化石，经鉴定认为其时代可能属石岩—二叠纪。本文根据以往的同位素资料、沉积环境分析和区域对比，认为这套变质岩系的原岩为二叠纪含煤沉积岩，可与福建的童子岩组中上部层位对比。  相似文献   

Study on Sampling Rule and Simplification of LiDAR Point Cloud Based on Terrain Complexity     

Qian-ning Zhang  Ze-chun Huang  Zhu Xu  Hai-bin Shang 《Journal of the Indian Society of Remote Sensing》2018,46(11):1773-1784

It is difficult to obtain digital elevation model (DEM) in the mountainous regions. As an emerging technology, Light Detection and Ranging (LiDAR) is an enabling technology. However, the amount of points obtained by LiDAR is huge. When processing LiDAR point cloud, huge data will lead to a rapid decline in data processing speed, so it is necessary to thin LiDAR point cloud. In this paper, a new terrain sampling rule had been built based on the integrated terrain complexity, and then based on the rule a LiDAR point cloud simplification method, which was referred as to TCthin, had been proposed. The TCthin method was evaluated by experiments in which XUthin and Lasthin were selected as the TCthin’s comparative methods. The TCthin’s simplification degree was estimated by the simplification rate value, and the TCthin’s simplification quality was evaluated by Root Mean Square Deviation. The experimental results show that the TCthin method can thin LiDAR point cloud effectively and improve the simplification quality, and at 5 m, 10 m, 30 m scale levels, the TCthin method has a good applicability in the areas with different terrain complexity. This study has theoretical and practical value in sampling theory, thinning LiDAR point cloud, building high-precision DEM and so on.  相似文献   

Initial results of centralized autonomous orbit determination of the new-generation BDS satellites with inter-satellite link measurements   总被引：3，自引：0，他引：3  

Chengpan Tang  Xiaogong Hu  Shanshi Zhou  Li Liu  Junyang Pan  Liucheng Chen  Rui Guo  Lingfeng Zhu  Guangming Hu  Xiaojie Li  Feng He  Zhiqiao Chang 《Journal of Geodesy》2018,92(10):1155-1169

Autonomous orbit determination is the ability of navigation satellites to estimate the orbit parameters on-board using inter-satellite link (ISL) measurements. This study mainly focuses on data processing of the ISL measurements as a new measurement type and its application on the centralized autonomous orbit determination of the new-generation Beidou navigation satellite system satellites for the first time. The ISL measurements are dual one-way measurements that follow a time division multiple access (TDMA) structure. The ranging error of the ISL measurements is less than 0.25 ns. This paper proposes a derivation approach to the satellite clock offsets and the geometric distances from TDMA dual one-way measurements without a loss of accuracy. The derived clock offsets are used for time synchronization, and the derived geometry distances are used for autonomous orbit determination. The clock offsets from the ISL measurements are consistent with the L-band two-way satellite, and time–frequency transfer clock measurements and the detrended residuals vary within 0.5 ns. The centralized autonomous orbit determination is conducted in a batch mode on a ground-capable server for the feasibility study. Constant hardware delays are present in the geometric distances and become the largest source of error in the autonomous orbit determination. Therefore, the hardware delays are estimated simultaneously with the satellite orbits. To avoid uncertainties in the constellation orientation, a ground anchor station that “observes” the satellites with on-board ISL payloads is introduced into the orbit determination. The root-mean-square values of orbit determination residuals are within 10.0 cm, and the standard deviation of the estimated ISL hardware delays is within 0.2 ns. The accuracy of the autonomous orbits is evaluated by analysis of overlap comparison and the satellite laser ranging (SLR) residuals and is compared with the accuracy of the L-band orbits. The results indicate that the radial overlap differences between the autonomous orbits are less than 15.0 cm for the inclined geosynchronous orbit (IGSO) satellites and less than 10.0 cm for the MEO satellites. The SLR residuals are approximately 15.0 cm for the IGSO satellites and approximately 10.0 cm for the MEO satellites, representing an improvement over the L-band orbits.  相似文献