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881.
882.
针对某些地勘单位干部选拔及用人过程中存在的任人唯亲等不正之风问题,从“考察失真、关系利益、任用随意、责任层次不清”四个方面进行了根源剖析,并着重在“强化责任意识、严格考察程序、规范领导行为、完善监督机制”等方面提出了整改措施。 相似文献
883.
2007年9月26日,中国地震局监测预报司在北京主持召开了“超宽频带观测应用研讨会”。出席研讨会的监测预报司领导有监测预报司司长李克,处长余书明,余书明处长主持会议。中国工程院院士许绍燮到会演讲。会议承办方中国地震局地震研究所所长姚运生到会致词,龚平副所长到会。出席 相似文献
884.
The inherent heterogeneity of geological media often results in anomalous dispersion for solute transport through them, and how to model it has been an interest over the past few decades. One promising approach that has been increasingly used to simulate the anomalous transport in surface and subsurface water is the fractional advection–dispersion equation (FADE), derived as a special case of the more general continuous time random walk or the stochastic continuum model. In FADE, the dispersion is not local and the solutes have appreciable probability to move long distances, and thus reach the boundary faster than predicted by the classical advection–dispersion equation (ADE). How to deal with different boundaries associated with FADE and their consequent impact is an issue that has not been thoroughly explored. In this paper we address this by taking one-dimensional solute movement in soil columns as an example. We show that the commonly used FADE with its fractional derivatives defined by the Riemann–Liouville definition is problematic and could result in unphysical results for solute transport in bounded domains; a modified method with the fractional dispersive flux defined by the Caputo derivatives is presented to overcome this problem. A finite volume approach is given to numerically solve the modified FADE and its associated boundaries. With the numerical model, we analyse the inlet-boundary treatment in displacement experiments in soil columns, and find that, as in ADE, treating the inlet as a prescribed concentration boundary gives rise to mass-balance errors and such errors could be more significant in FADE because of its non-local dispersion. We also discuss a less-documented but important issue in hydrology: how to treat the upstream boundary in analysing the lateral movement of tracer in an aquifer when the tracer is injected as a pulse. It is shown that the use of an infinite domain, as commonly assumed in literature, leads to unphysical backward dispersion, which has a significant impact on data interpretation. To avoid this, the upstream boundary should be flux-prescribed and located at the upstream edge of the injecting point. We apply the model to simulate the movement of Cl− in a tracer experiment conducted in a saturated hillslope, and analyse in details the significance of upstream-boundary treatments in parameter estimation. 相似文献
885.
空间关联规则可以从空间数据库中发现空间对象之间的隐含的、不明确的空间关系。空间数据库中空间关联规则挖掘研究是空间数据挖掘和知识发现(SDMKD)的主要内容,其主要问题是多层,多关系的规则发现问题。本文把元模式与空间关联规则挖掘相结合介绍了挖掘地理信息系统(GIS)中空间数据库关联规则的常用步骤方法。 相似文献
886.
887.
The features of climate change and their effects on glacier snow melting in the past 50 years (1961–2010) in Xinjiang were studied. Regional climate data for 49 meteorological stations in the Tianshan Mountains and the northern and southern areas of Xinjiang were collected with the aid of techniques such as climatological statistical diagnosis, regional climate models, remote sensing, and geographic information system. The annual average temperature displayed a rising trend across the Tianshan mountainous area and both areas of Xinjiang. The trend was particularly apparent in winter and autumn with the rate of increase in the annual average minimum temperature being significantly higher than that of the maximum temperature. Rainfall also tended to increase in all three areas over the 50-year period, with the magnitude of change being highest in the mountainous area followed by northern Xinjiang and then southern Xinjiang. As a result of the rising temperatures, there was a negative material balance among the region's glaciers, of which the year 1982/1983 was the key year for the development of Tianshan mountain glacier snow. After this date, glacial ablation intensified with an annual change increase in average temperature of 1 °C, leading to a glacier material balance change of about 300 mm. To establish rainfall and temperature sequences for three regional climate change scenarios in the 2011–2050 period, we adopted the delta method using actual measurements during the 1961–2000 period against corrected data from rainfall and temperature simulations. All three scenarios indicated that temperatures will continue to increase, that the increase in rainfall may decrease in mountainous regions but will increase in the basin, and that the speed of glacial ablation in Xinjiang will continue to accelerate. 相似文献
888.
889.
当前,中国正处于产业结构调整、升级的关键时期。产业升级的关键在于高端技能型人才的培养,而人才培养的落脚点又在于职业院校的教学质量提升。通过对中、日、德三国工匠精神的研究,得出其本质是精益求精、惟精惟一及专注专业。结合高职工程测量人才培养的特点,将工匠精神导入人才培养方案中,同时积极利用校园文化、校企合作培育工匠精神,探索一条德育、技能协同培养的路径,有利于学生技能的提升及职业精神的养成。 相似文献
890.