DINI-11电子水准仪的使用及评价

本文对DINI－11电子水准仪观测使用的基本情况，抗干扰能力，存在的问题等做了介绍，认为DINI－11电子水准仪完全可以替代Ni002补偿式自动安平水准仪。     

DINI12电子水准仪在台站短水准测量中的应用

主要介绍了DINI12电子水准仪的特性、原理、检测方法及代替原有光学水准仪在台站短水准测量中的应用,并结合电子水准仪的实际观测数据,对该仪器的使用方法和测量精度进行了探讨。     

南通地震台数字水准仪观测效果的分析

从南通地震台短水准背景出发,介绍了DiNi12数字水准仪代替原有光学水准仪在南通地震台应用的效果,论述了数字水准仪在台站形变观测中发挥的作用及注意事项。文章结合实例对数字水准仪与Ni002A仪器观测的资料进行了对比分析,验证了数字水准仪的优点和实用价值。     

DINI11数字水准仪观测资料处理软件

介绍了编制DINI11数字水准仪观测资料后,处理软件的设计思路和实现方法,该软件自动完成观测资料入库、计算、打印手簿、成果表和画时序图等任务。     

数字水准仪与光学水准仪对比观测研究

近年来,在高精度水准测量领域数字水准仪逐渐呈现出取代光学水准仪的趋势。本文通过实际观测实验,对比分析了两类水准仪的优势与不足。结果表明,光学水准仪相对较重,但性能稳定,而数字水准仪轻巧、操作方便,能很好地避免人为读数误差。在实际工作效率上光学水准仪占优,测量精度的稳定性好于数字水准仪。     

数字电子水准仪DiNi10性能实测分析

对蔡司公司的ＤｉＮｉ１０数字电子水准仪,通过主要指标测试、条件试验和６６ｋｍ的实际外业测量,特别是与精密自平水准仪Ｎｉ００２的４０ｋｍ同桩平行测量试验,论述了此种仪器的性能及其作业规律和特点。结果表明该仪器可用于一等水准测量和精密地形变监测。指出了该仪器的不足之处。     

电子水准仪观测资料处理系统的研制

本文着眼于台站水准数字化改造的实际需要，对电子水准仪投入使用前及使用中所涉及的仪器检查项目和观测数据的后续处理工作进行二次开发，研制了“电子水准仪观测资料处理系统”。该系统包括仪器检查、观测成果处理和绘图三部分。使台站水准测量结束了人工读数、手工记录和点图、人工计算的历史，实现了电子水准仪观测资料处理的微机化和自动化。     

数字化水准仪应用于跨断层水准测量的性能分析

跨断层水准观测是一种高精度的测量工作,对水准仪的精度、稳定性等方面提出了较高的要求,因此仪器老化所产生的仪器性能衰减成为行业内普遍关注的问题。本文分析了Trimble DiNi12型数字水准仪在整个生命周期中的第1年、第4年和第7年的产出数据,结果表明这种数字水准仪在使用的前期性能衰减快,中后期可保持相对稳定的状态。Trimble DiNi12型数字水准仪与Leica DNA03型数字水准仪分别投入使用的第1年内测段往返测闭合差表明,Trimble DiNi12型水准仪所能达到的实际精度优于Leica DNA03型水准仪。进一步分析可知,Trimble DiNi12型水准仪在稳定性上也有一定优势,这和实际的使用情况相符。     

DiNi-11数字水准仪在断层形变台站测量中的应用

电子自动数字化水准仪已进入市场 ,并将作为光学水准仪的替代产品被广泛应用。中国地震局在“九五”规划期间 ,为形变台站等有关单位的水准测量配备了一批 Di Ni-1 1数字水准仪。安徽合肥形变台自 2 0 0 0年 1月 1日起正式投入观测。执行“大地形变台站测量规范” (短水准测量 )及“使用电子水准仪的规范中有关条款和附录要求的变化情况”的规定要求 ,分析处理了 1年的观测资料 ,对 Di Ni-1 1数字水准仪的性能和适合台站定点水准测量的工作方法、操作规程进行了分析讨论 ,研究探讨了该仪器用于定点短水准测量的观测精度及测量误差。1　 Di…     

自动安平水准仪磁致误差函数模型与数据分析

利用物理摆原理导出了自动安平水准仪磁致误差的理论函数模型,建立了地磁场中的观测方程。通过实测资料,分析了地磁场对Ｎｉ００２水准仪的影响,并对观测误差和Ｆ值的测定精度进行了讨论。     

Temporal variations and scaling of streamflow and baseflow and their nitrate-nitrogen concentrations and loads

The patterns of temporal variations of precipitation (P), streamflow (SF) and baseflow (BF) as well as their nitrate-nitrogen (nitrate) concentrations (C) and loads (L) from a long-term record (28 years) in the Raccoon River, Iowa, were analyzed using variogram and spectral analyses. The daily P is random but scaling may exist in the daily SF and BF with a possible break point in the scaling at about 18 days and 45 days, respectively. The nitrate concentrations and loads are shown to have a half-year cycle while daily P, SF, and BF have a one-year cycle. Furthermore, there may be a low-frequency cycle of 6–8 years in C. The power spectra of C and L in both SF and BF exhibit fractal 1/f scaling with two characteristic frequencies of half-year and one-year, and are fitted well with the spectrum of the gamma distribution. The nitrate input to SF and BF at the Raccoon watershed seems likely to be a white noise process superimposed on another process with a half-year and one-year cycle.     

燕郊等测点迁移优化与地磁观测研究

为优化地磁观测条件，开展了燕郊、夏垫等测点迁移工作；按照测眯迁移原则与实施技术方案，完整地收集并整理了地质构造与地球物理等方面的基本资料；进行了野外实地勘察，磁场梯度的测量，确定了新测点，在新老测点上进行了较长时间的地磁场对比观测；应用多种方法分析研究了地磁对比观测资料，结果表明，新老测点与有关测点的地磁变化具有良好的一致性，并得到了新老测点之间的地磁数据的按点差。     

东、南洞庭湖的径流、泥沙特征及冲淤规律

通过实地调查并对1957年以来水文、泥沙观测资料做系统分析和计算,探讨东、南洞庭湖出、入湖水量、沙量的年际和年内变化特征,以及长江下荆江段裁弯对湖区径流和泥沙的影响。提出了湖区泥沙汛淤枯冲的变化规律及水位升降与湖区泥沙冲淤的关系;论证了丰、平、枯年湖区淤积严重,面积日益缩小对径流的调节作用正在减弱。     

GIS与防灾减灾

地理信息系统(GIS)在我国已得到广泛的应用。在简要介绍G1S的发展历程、特点和发展趋势的基础上，重点从防灾减灾的角度介绍了GIS在气象灾害、地震灾害、地质灾害等领域的应用成果。     

Seismics and optics: hyperbolae and curvatures

We rederive and generalize hyperbolic moveout formulae for the common-midpoint (CMP) gather and for the zero-offset (ZO) section that can be efficiently used for macro-model-independent reflection imaging in two-dimensional media. The hyperbolic moveout formulae for the common-midpoint gather are obtained from different Taylor series expansions of a particular parametric moveout surface defined in the multicoverage data space. Such a moveout surface involves three kinematic wave-field attributes of two hypothetical waves, which have to be determined by a coherency analysis. By using hyperbolic moveout curves in the CMP gather and in the ZO section one can determine these attributes in two steps. The relationships between the local shapes of the interfaces and the attributes of the hypothetical wave-fields attributes are considered by means of geometrical optics. The determination of these attributes allows to perform a macro-model-independent ZO simulation and a subsequent inversion.     

Assessing Groundwater Depletion and Dynamics Using GRACE and InSAR: Potential and Limitations

In the last decade, remote sensing of the temporal variation of ground level and gravity has improved our understanding of groundwater dynamics and storage. Mass changes are measured by GRACE (Gravity Recovery and Climate Experiment) satellites, whereas ground deformation is measured by processing synthetic aperture radar satellites data using the InSAR (Interferometry of Synthetic Aperture Radar) techniques. Both methods are complementary and offer different sensitivities to aquifer system processes. GRACE is sensitive to mass changes over large spatial scales (more than 100,000 km²). As such, it fails in providing groundwater storage change estimates at local or regional scales relevant to most aquifer systems, and at which most groundwater management schemes are applied. However, InSAR measures ground displacement due to aquifer response to fluid‐pressure changes. InSAR applications to groundwater depletion assessments are limited to aquifer systems susceptible to measurable deformation. Furthermore, the inversion of InSAR‐derived displacement maps into volume of depleted groundwater storage (both reversible and largely irreversible) is confounded by vertical and horizontal variability of sediment compressibility. During the last decade, both techniques have shown increasing interest in the scientific community to complement available in situ observations where they are insufficient. In this review, we present the theoretical and conceptual bases of each method, and present idealized scenarios to highlight the potential benefits and challenges of combining these techniques to remotely assess groundwater storage changes and other aspects of the dynamics of aquifer systems.