基于MATLAB的BP神经网络在南通市地下水质量评价中的应用

利用MATLAB的神经网络工具箱,建立了地下水质量的评价模型,并对南通市地下水水质进行了评价,评估结果反映了南通市地下水质量的现状,表明BP神经网络模型具有很强的学习和自适应能力,避免了在权值和阀值确定中人为因素的影响,增加了评价结果的客观性、公正性和精度,具有一定的实用价值。     

南通市地下水开采现状及开发利用研究

近年来,随着地下水开采量的剧增,南通市地下水环境不断恶化,如何科学、高效、合理地利用地下水资源成为我们水利工作者关注的重点,在介绍南通市水文地质概况和地下水开采现状基础上,分析了第Ⅲ承压水位动态变化特征,初步探讨地下水强烈开采引发地面沉降、水质咸化等环境地质问题,提出地下水开发利用规划,并对地下水压采效果进行了简单评估。     

洛阳市地下水环境动态特征分析

洛阳市地下水资源相对缺乏,开展调查研究保护地下水,对地下水资源可持续利用具有一定的意义。通过对洛阳市地下水动态监测,调查市区地下水资源开发利用现状,分析地下水水位、水化学、水温动态特征,进行水环境影响分析,为地下水合理开采利用提供依据。     

辽源市水污染现状及防治措施

辽源市位于东辽河上游河谷平原上,是吉林省重要的工业城市。市区为低山丘陵环绕,地表水系发育,第四纪堆积层4～9米,市区环境容量小,自净功能差。市内大部分厂矿无处理“三废”设施,而且随便排放,使市区地表水、地下水污染严重,一些供水井报废。同时污染已影响到市区下游东辽河沿岸地带的其它城镇。一、水质污染现状市区地表水、地下水,由于强烈的人为活动影响,已基本改变了天然条件下的水质     

南通市水资源开发利用现状及用水变化趋势分析

根据南通市水资源开发利用现状,对地表及地下水资源量进行综合分析,预测南通市未来十年的用水变化趋势。分析结果表明：未来十年用水量急剧增长,涨幅超过50%,水资源量供需矛盾加剧;提出工业上优化产业结构布局、改进工序工艺、提高重复利用率以及农业上城乡管网改造、普及和推广农灌节水设施等措施,保证南通市用水供给。     

基于GIS的磐石市地下水环境质量分析

基于ArcGIS建立了磐石市29个监测点的水质信息数据库,采用灰色聚类法进行地下水环境质量评价。利用GIS的空间分析功能,分析地下水中常规组分的空间分布特征,掌握了地下水质量状况。磐石市大部分地区地下水质量良好,达到、级标准。地下水中化学组分的含量从郊区向市区逐渐增加,市区地下水质量为、级标准。地下水已遭受污染,地下水开采降落漏斗区地下水位的持续下降是市区地下水遭受污染的主要诱发因素。     

许昌市区水资源及水污染问题论评

本文对昌市区地下水资源的赋存、补给条件以及开采现状，地表水和地下水的污染程度都作了较详尽的评述，并指出由于量开采引起的地面沉降正在逐年加剧，由此而给许昌市区今后的工农业发展及人民的生活安全埋下了一个隐患。针对许昌市水资源私有制和严重污染的现状，提出了许多治污、开源节流的合理建议；这不仅对昌市，就是对类似水资源条件的其它中小城市也是一个良好的借鉴。     

贵阳市地下水污染现状评价及防治对策

通过对贵阳市有关地质资料的综合分析以及实现调查、取样,根据地下水质量标准,并运用单项和综合污染指数法对贵阳市地下水进行了污染现状评价。评价结果显示贵阳市广大农村地区地下水水质较好,但人口集中的市区和工矿业密集区地下水污染较为严重。并根据综合评价结果和贵阳市环境地质条件,提出了相应的防治对策。     

安阳市地下水回灌的可行性分析

通过对安阳市区水资源的供需现状和发展趋势分析,提出实施地下水人工回灌的必要性和可行性;在对地质构造、水文地质条件、水源条件、工程效益等进行分析后,认为在安阳市区实施地下水人工回灌是可行的,并提出了4条合理化建议.     

江苏南通市地下水主采层水位动态区域演变特征

南通市地下水主采层Ⅲ承压水为赋存于第四系地层中的松散岩类孔隙水,已成为区内广大乡镇水厂的主要供水水源,全区性开采。1998年完成的《南通市地下水资源评价报告(1∶10万)》,为水资源主管部门地下水规划管理的依据。以1997年为基准对比年,阐述1997年以来区内地下水主采层水位动态的演变特征,为加强地下水资源的规划管理,保护地质环境提供一定的依据。     

Unity of the national and the international in the socio-cultural development of the peoples of the USSR

International unity is becoming ever stronger in this country owing to an increasing similarity in the development of the cultural environment. This comprises the provision of all the country's republics with a sufficient number of schools, theatres, and other institutions and cultural information media in accordance with the needs of the population. An important part is played by the rise in ‘the general educational level, as well as the level of professional qualifications and skills. Among all the Soviet nations and nationalities, this rise being more rapid among formerly backward peoples. Prominent among the factors of internationalization is the progressive development of the nationalities’ cultural resources, while professional culture is being increasingly brought within the reach of the masses.The implementation of the nationalities policy promotes the all-round development of all Soviet nations and nationalities, their drawing together, the upsurge of the individual capabilities of every Soviet citizen.     

Report of the restudy of the defined global stratotype of the base of the Silurian System

The Global Stratotype Section and Point （GSSP） for the base of the Silurian System was defined in 1985. Since that time, a number of researchers have suggested that this section has serious deficiencies for use as a GSSP. As a result, in 2000, the Subcommission on Silurian Stratigraphy （SSS） proposed undertaking a formal restu@ of this GSSP, which was subsequently approved by the International Commission of Stratigraphy （ICS）. The result of this restudy was the formal proposal that the current GSSP, at 1.6 m above the base of the Birkhill Shale, at Dob＇s Linn, Scotland, should be maintained as the same locality and stratigraphic level, but the bios- tratigraphical definition of the boundary should be revised. The previously defined, basal Silurian grapto- lite zone, the Parakidograptus acuminatus Zone, should be subdivided into a lower Akidograptus ascensus Zone and a higher E acuminatus Zone. The base of the A. ascensus Zone, marked by the first appearance of A. ascensus, should be regarded as the biostratigraphic mark for the base of the Silurian. This proposal has now been formally approved by the SSS and ICS, and ratified by International Union of Geological Sciences. This is the first GSSP to undergo formal restudy and redefini- tion, and the proposal also included a recommended procedure for restudy of GSSPs.     

Deviation of the major axis of the inertia ellipsoid of the Moon from the direction toward the Earth

It is known from observations that the center of mass of the Moon does not coincide with the geometric center of its figure, and the line connecting these two centers is not aligned with the direction toward the center of the Earth, instead deviating toward the Southeast. This stationary deviation of the axis of the inertia ellipsoid of the Moon to the South of the direction toward the Earth is analyzed. A system of five linear differential equations describing the physical libration of the Moon in latitude is considered, and these equations are derived using a new vector method taking into account perturbations from the Earth and partly from the Sun. The characteristic equation of this system is obtained, and all five oscillation frequencies are found. Special attention is paid to the fifth (zero) frequency, for which the solution of the latitude libration equations are stationary and represents a previously unknown additional motion of the rotational axis of theMoon in a cone with a small opening angle. In contrast to the astronomical precession of the Earth, the rotation of the angular-velocity vector is in the positive direction (counter-clockwise), with the period T ₃ = 27.32 days. On this basis, this phenomenon has been named “quasi-precession.” This quasi-precession leads to a stationary inclination of the major axis of the inertia ellipsoid of theMoon to the South (for an observer on Earth), making it possible to explain one component of the observed deviation of the center of mass of the Moon from the direction toward the Earth. The opening angle of the quasiprecession cone is approximately 0.834″.     

The Tendencies of the Development of the Mineral-Resources Sector at the Turn of the Century

Important tendencies in development of the world mineral-resources sector at the beginning of the 21st century were an increase in production and consumption of mineral materials differentiated by types of metals and nonmetallic mineral raw materials, by countries and regions, as well as the concentration of the production of mineral raw materials in a small number of countries, and a reduction in industrial reserves of minerals in the world economy, even at the current stage of their extraction. These tendencies should be taken into account in working out a strategy for development of the Russian mineral raw-material base.     

Causes of the famine among the rural population of the Sahelian zone of the Sudan

Taking the example of W Sudan, an analysis of the climatic incidents leading to the two recent famine disasters is made. On this natural background, the human side is investigated. Focus is directed towards the fragile economic structure of the famine-prone population groups. An early-warning system for famine in the Sahelian Zone is proposed taking grain production and storage, livestock development and the relationship between the prices of livestock and grain as major indicators.     

东濮凹陷北部沙河街组三段中亚段沉积环境分析

东濮凹陷北部沙三中亚段广泛发育盐岩和烃源岩,这两个看似不能共存的物质却在这里互层共生。该时期研究区沉积特征为多盐韵律与多层烃源岩互层共生、连续沉积,单个盐韵律厚度从几米到十几米,烃源岩有机质丰度高、类型好。平面上,两者在湖盆沉积沉降中心共生;垂向上,高有机质丰度、好干酪根类型与高盐度地层具有较好的对应关系。因而成为恢复古气候和古环境的重要研究对象。通过岩石学、古生物学以及Sr/Ba、B/Ga、(V+Ni+Mn)、Fe/Mn、Sr/Cu、Mg/Ca、V/(V+Ni)、稀土元素含量和氯同位素等方法对凹陷北部沙三中亚段的沉积环境进行研究。结果表明,凹陷北部沙三中亚段为深水沉积的还原环境,古盐度较高,达到半咸水-咸水沉积;微量元素和孢粉化石特征表明研究区沙三中亚段为温暖潮湿的环境。     

郯庐断裂南段研究进展与断裂性质讨论

据1：5万区域地质调查和专题研究资料，就郯庐断裂带是否南延与消失的原因，其与大别—苏鲁造山带交截形成的假位错效应，以及与中新生代沉积盆地形成演化的关系等作了新的阐述。在此基础上，讨论了郯庐断裂带是否为巨大的左行平移断层或转换断层。认为郯庐断裂带可能是在“古郯庐带”的基础上于早侏罗世重新活动、白垩纪强烈活动的地堑型枢纽断裂带。     

The Importance of the Precipitation and the Susceptibility of the Slopes for the Triggering of Landslides Along the Roads

In order to characterise the influence of the heavyrains on the observed landslides during the 1996–1997hydrological cycle, rainfall records for the last 100years are analysed from 104 stations in easternAndalusia. Regarding the amounts of rain recordedbetween October 1996 and March 1997 in the 104stations studied, 31 presented new all-time records;15 presented values that were 80–100% of thepre-1995 record; 49 stations, 80–50%; and 9stations, < 50%. A map has been devised of thesusceptibility of the materials through which thesouth-eastern Andalusian road network crosses,together with an inventory of the damage caused byinstability phenomena on banks and cuttings of theroad network during the winter of 1996–1997. Therelationships between the rainfall during the studyperiod, the damage caused to the road network and thesusceptibility of the materials affected are analysed.The results indicate that there is a clearcorrespondence between the rainfall recorded and thesusceptibility of the materials with the inventorieddamage. It is concluded that the widespread seriousdamage caused in early 1997 to the roads andsurrounding areas in the Alpujarra region and thecoast of the Province of Granada was mainly caused bythe extraordinarily heavy rains. However, considerablyless damage was observed where the susceptibility ofthe terrain is low, thus highlighting the extremeusefulness of terrain-susceptibility maps for riskprevention and territorial planning.