GIS-Hydrogeochemical Model of the YaoundéFractured Rock Aquifer, Cameroon: Aquifer Setting, Seasonal Variations in Groundwater-Rock Interaction and Water Quality

This study of the gneiss-fractured-rock aquifer in Yaoundé capital of Cameroon determines: the aquifer setting-flow systems, the aquifer type, seasonal variations in rock-water interactions, evolution of the hydrogeochemical processes, physicochemical parameters and the suitability for domestic-agro-industrial use of the groundwater. Physicochemical field tests were carried out on 445 wells during four seasons for EC, pH, TDS, Temperature and static water level from July 2016 to May 2017. 90 well samples were analyzed 45 samples per season: wet/dry. 38 borewell logs were used together with structural data to determine the aquifer setting. The field physico-chemical and laboratory analysis data of well samples were mounted unto various GIS software platforms: Global mapper, AqQa, Aquachem, Rockworks, Logplot7, Surfer and ArcGIS, to get indices/parameters/figures, by use of Durov’s, Piper’s and Gibbs diagrams, Water quality index WQI, USSL ratio, Sodium Absorption ratio SAR, Percent sodium %Na, Kelly Ratio KR, Magnesium Absorption Ratio MAR, Total Hardness TH, Residual Sodium Carbonate RSC and Permeability Index PI that were determined. The process of groundwater ions acquisition is three-fold: by recharge through atmospheric precipitation, by ion exchange/simple dissolution between the rock-groundwater and by groundwater mixing in its flow path. Water types are Ca-HCO3, Mg-HCO3 and Mg-Cl while hydrogeochemical facies are Ca-Mg-HCO3 and Ca-Mg-Cl-SO4. Most water samples are fresh, potable and soft all seasons. The hydrogeological conceptual model is that of a three-layered single phreatic fractured-rock-aquifer while other researchers postulated a two-aquifer, phreatic and semi-confined, two-layered model.

Nonlinear Dynamic Characteristic Analysis of the Shaft System in Water Turbine Generator Set

A 3D finite element vibration model of water turbine generator set is constructed considering the coupling with hydropower house foundation. The method of determining guide bearing dynamic characteristic coefficients according to the swing of the shaft is proposed, which can be used for studying the self-vibration characteristic and stability of the water turbine generator set. The method fully considers the complex supporting boundary and loading conditions; especially the nonlinear variation of guide bearing dynamic characteristic coefficients and the coupling effect of the whole power-house foundation. The swing and critical rotating speed of an actual generator set shaft system are calculated. The simulated results of the generator set indicate that the coupling vibration model and calculation method presented in this paper are suitable for stability analysis of the water turbine generator set.

Study of Interval Type-2 Fuzzy Controller for the Twin-tank Water Level System

For dealing with large static error due to poor immunity of the traditional fuzzy control, a novel interval type-2 fuzzy control system is proposed. By extending the typical membership functions to interval type-2 membership functions, the proposed control system can efficiently reduce the uncertain disturbance from real environment without increasing the design complexity. The simulation results on the water tank level control system showed that the proposed method succeeded in better static and dynamic control with stronger robust performance than the traditional fuzzy control method.

New Methods of Fitting the Membership Function of Oceanic Water Masses

After reviewing the analytical theories of T S curve, some methods of T S relationship, and fuzzy sets for studying water masses, new methods of fitting the membership function of oceanic water masses are presented based on the characteristics of T S curve family of oceanic water masses. The membership functions of oceanic Subsurface Water Mass with high salinity and Intermediate Water Mass with low salinity are fitted and discussed using the new methods. The proposed methods are useful in analyzing the mixing and modifying processes of these water masses, especially in tracing their sources. The principles and formulae of the new methods and examples are given.

DISCUSSION OF SOME CONCEPTIONS OF A WATER MASS BASED ON THE THEORY OF FUZZY SETS

The fundamental principle for differentiating water masses is a strict consideration of their relative "interior homogeneity" and obvious "exterior differences" with others in characteristics. The conceptions of water type, water mass and water system are dealt with on the basis of the theory of fuzzy sets. A proposal to apply the theory of fuzzy sets to define the water mass and its core, independent area, boundary and mixing area is put forward.As an example, the membership function of the surface water masses in the Yellow Sea and East China Sea in August, 1979, are considered. Their cores, independent areas, boundaries, mixing areas and the approximation degrees between different water masses are calculated respectively. The water masses are ranged according to their fuzzy degrees.

INVESTIGATION ON MAKING MEMBERSHIP FUNCTION OF WATER MASS FROM MIXING MODIFIED PROCESS

A water mass in the sea area under investigation is defined as a fuzzy subset in the discourse universe. Possible forms of membership function of water masses in the mixing modified process are discussed with the mixing theory for conservative concentration of sea water. It may provide bases for making membership functions. Results in this paper may be extended and applied to shallow water. Examples and discussion are given in this paper.

Leaf Water Status and Its Relationship with Reproductive Responses of Common Bean (<i>Phaseolus vulgaris</i>L.) Genotypes under Water Stress

Two tolerant (BB24 and BB43) and two susceptible (BARI busbean-2 and BB04) genotypes of common bean (Phaseolus vulgaris L.) were evaluated for their water status and its relationship with reproductive responses under continuous water stress (50% field capacity) and control (80% field capacity) conditions in a net house covered with polyethylene sheet at the Bangabandhu Sheikh Mujibur Rahman Agricultural University, Bangladesh. Under water stress condition, the susceptible genotype namely BB04 exhibited more negative leaf water potential (LWP) which was followed by that of BARI bushbean-2 in all the time of the day except at noon. The tolerant genotype namely BB24 exhibited less negative LWP at noon. The tolerant genotypes maintained higher relative water content (WRC) than the susceptible ones from dawn to dusk. The relationship between RWC and LWP was examined separately for four genotypes under water stress condition. The genotype BB24 showed a smaller decrease in RWC with more negative LWP than BB04. Water stress reduced pod setting ratio. The relationship between the leaf water status and reproductive responses showed that the genotype with a little reduction in mid-day drop of RWC or with high mid-day RWC displayed a high pod setting ratio.

How to Investigate the Setting Kinetics of Refractory Castables——A Review of Methods and Their Relevancy for Technical Use

This article contributes to a meaningful interpretation of results gathered by in-situ measurements of sonic velocity, electrical conductivity and the change of temperature during setting and curing of LC refractory castables. All said monitoring techniques are well known in the refractory community and are well documented in the literature. However, the time dependent changes of the said properties are not well correlated to mineralogical and in consequence technological changes of the material during setting and curing. The basic interest of refractory users of course is to define the time at which the installation or the pre-shape construction element can be demoulded. This is in principle possible with the methods listed above. However, after water addition the time de- pendent changes of sonic velocity, electrical conductivity and temperature are diverse as there are possible combi- nations of cements, microfines and surface-active additives. In further the ambient conditions, temperature and relative humidity have a strong influence on these properties and this does not only mean a simple time-shift. Up to now the results are more confusing than helpful to determine the best time for demoulding pre-shapes and refractory linings. Recent research at Koblenz University of Applied Science contributes to a deeper understanding of the setting behaviour, because besides the physical evolution of the said parameters the time dependent formation of hydrate phases is also investigated by means of gravi-metric method. The proposed presentation will show detailed insights in the evolution of refractory castables during setting and curing.

Wave Height Transformation and Set-up Between A Submerged Permeable Breakwater and A Seawall

In this study, we investigated wave transformation and wave set-up between a submerged permeable breakwater and a seawall. Modified time-dependent mild-slope equations, which involve parameters of the porous medium, were used to calculate the wave height transformation and the mean water level change around a submerged breakwater. The numerical solution is verified with experimental data. The simulated results show that modulations of the wave profile and wave set-up are clearly observed between the submerged breakwater and the seawall. In contrast to cases without a seawall, the node or pseudo-node of wave height evolution can be found between the submerged breakwater and the seawall. Higher wave set-up occurs if the nodal or pseudo-nodal point appears near the submerged breakwater. We also examined the influence of the porosity and friction factor of the submerged permeable breakwater on wave transformation and set-up.

Fenlong Cultivation-the Fourth Set of Farming Methods Invented in China

The basic theory and effect of the new farming method of ＂Fenlong＂ cultivation which has been included in the main extension technology of Ministry of Agriculture of the People＇s Republic of China is fully illustrated for the first time, and it is the fourth set （generation） of farming modes and methods following manpower, animal and mechanical （tractor） farming. It follows the natural law to achieve soil activation, water saving, oxygen increase, warming and desalination through the active use of natural resources like soil, rainfall and solar energy, thereby promoting a new round of natural agricultural production and quality improvement and water con- servation, which has crop yield increase by 10%-30%, quality improvement of 5%, natural precipitation retaining increase by100%. The characteristics and mechanism are the use of spiral drill for one-time completion of the land preparation by drilling vertically to 30-50 cm of soil layer through high speed peeling. After instant high temperature and many fierce impacts, mechanical frictions, it could achieve the multiplication of the number of loose soil, soil physical modification and expansion of the soil nutrients, reservoirs, oxygen, microorganisms （＂Four pools＂）. Fenlong cultivation can give birth to new farming culture and civilization, and it can achieve the physical ＂desalinized＂ transformation and utilization of saline soil. The formation of Fenlong green farming technology system makes it possible to invent the farming tools of ＂serf-propelled Fenlong machinery＂ that has got the patent, and it is the method for farmland （dry land, paddy field） Fenlong cultivation, saline-alkali soil smash-ridging cultivation and for the abundance of grass ecology on degraded grassland. The application of Fenlong ＂4＋1＂ （arable, saline-alkali soil, grasslands, Sponge City＋rivers） green development in China can achieve the ＂double safety＂ of food and living space.

低装载液箱晃荡砰击载荷的CLSVOF数值模拟(英文)

应用CLSVOF数值方法模拟并计算液箱剧烈晃荡的砰击载荷。该方法由level-set方程获得网格内自由液面法向量,并由PLICVOF方法重构自由液面,然后在重构后的自由液面上进行level-set方程的重新初始化。应用该方法,模拟了横摇以及横荡共振激励作用下低装载液箱的晃荡砰击载荷,并与实验结果进行了对比,计算结果与实验结果较为一致。

宿迁市服务业用水定额编制与思考

服务业是现代经济的主要组成部分,也是城市用水的重要方面。结合相关政策以及节约用水管理需要,制定宿迁市服务业用水定额。针对宿迁市《服务业用水定额》制定过程中的编制原则、现状分析、编制方法以及研制过程,进行深入分析和探讨并提出实施建议,以期为服务业节水管理工作提供参考。

水电机组轴系—分数阶基础的非线性耦合动力学研究

为研究不同基础动力特性对水电机组振动的影响,将分数阶理论引入到水电机组—基础的耦合动力学建模与分析中。首先,对比分析了单自由度等效基础体系在整数阶和分数阶下的中高频特征,研究了不同阻尼项分数阶对基础宽频特性的影响。然后,对比分析了基础不同分数阶次与整数阶的非线性耦合动力效应。结果表明,基础的分数阶阻尼特性对机组的振动具有明显的影响,与传统的整数阶系统相比,考虑分数阶基础的耦合效应能够更全面、更丰富地反映机组的振动。

整体偏联系数与随机模拟耦合的水资源承载力评价方法

为定量评价区域水资源承载力、挖掘区域水资源承载力评价过程中的不确定性信息、合理构造集对分析联系数分量的迁移率矩阵,提出采用基于同异反总关系程度“a+b+c”度量的整体偏联系数方法计算得到修正联系数分量,再结合三角模糊数随机模拟方法,构建了基于整体偏联系数与随机模拟耦合的水资源承载力评价方法。文中模型在宿州市2011—2019年的应用结果表明:宿州市水资源承载能力总体偏低,除2018年以外,其余年份水资源承载力评价等级均在2级以上,但是评价等级有逐年下降趋势,水资源承载力呈现正向改善的趋势;水资源承载力级别特征值全部落在本文方法计算出的评价区间内,认为该方法合理,与基于偏联系数原理构造的迁移率矩阵计算的评级等级基本一致且误差更小,说明该方法在联系数分量迁移转化时更合理,可为判别区域水资源承载力评价等级、合理调控区域水资源承载力提供有效途径。

基于集对分析的新疆喀什地区水资源可持续利用评价

为了分析新疆喀什地区水资源可持续利用现状及其影响因素,基于“驱动力-压力-状态-影响-响应”(driving-pressure-state-impact-response,DPSIR)模型选取17项评价指标构建水资源可持续利用评价指标体系,分别采用能够较好揭示不确定性系统内在规律的集对分析法与偏联系数法建立切实适用于本区域的可持续评价模型,对新疆喀什地区2010—2019年水资源可持续利用状况进行了综合评价,并结合三元半偏减法集对势诊断该区域发展态势,识别影响其可持续发展的脆弱性指标.结果表明:新疆喀什地区各年水资源可持续利用状况不一,其中,2010—2013年与2017年水资源可持续利用情况较好,区域内水资源得到了较好的开发与利用,2014—2016年、2018—2019年区域内政策规划基本合理,水资源综合可持续能力一般;集对分析法对喀什地区水资源可持续评价具有较好的适用性;影响喀什地区水资源可持续利用发展较为脆弱的指标包括人口密度、人均GDP、生活用水量与生态用水量.研究结果可为促进新疆喀什地区水资源可持续利用发展提供一定的科学依据.

STUDY ON A PRECISE ON-SPOT CALIBRATION METHOD FOR DISTRIBUTED STEREO REFERENCE POSITION-SETTING

A high precision method used for on-spot calibration of distributed stereoreference position setting is presented. The high measuring accuracy in stereo reference calibrationis derived from using a high precision water level instrument and an accurate height verniercaliper. It settles the problem of reference calibration effectively and accurately, without usinglarge coordinate measuring machines (CMM). It is more adaptable and precise than traditionalcalibration methods applying theodolites or autocollimators. The error sources of this method areanalyzed in detail and several methods are developed to eliminate the calibration error.Anoptimizing swallowtail-like anchor target is developed. Experiments show that the calibrationaccuracy can be limited within 0.06 mm in the range of 3～5 m and 0.03 mm with optimizing anchortarget. This method can be widely used in on-spot calibration.

水性高粘喷涂速凝橡胶沥青防水涂料的研发与应用

制备了一种双组分水性高粘喷涂速凝橡胶沥青防水涂料,主剂A组分为阴离子乳化沥青、阴离子氯丁胶乳和阴离子丁苯胶乳,固化剂B组分为硫酸锌水溶液,两个组分通过专用喷涂设备喷出后雾化析水成膜。探讨了各组分配比对涂料性能的影响以及涂料与不同自粘防水卷材复合应用的效果,结果表明,200#乳化沥青∶90#乳化沥青质量比1∶3、氯丁胶乳含量为20%、丁苯胶乳含量为12%制得的涂料性能最佳。该涂料可与不同类型的自粘防水卷材复合应用,粘结效果均较好。

Coal and gas outburst prevention using new high water content cement slurry for injection into the coal seam

As coal and gas outburst is one of the most serious mine disasters, it is very important to at least control it if not prevent it from occurring. Injecting cement slurry or grouting into the coal seam can strengthen the seam, increase its rigidity coefficient(f), and reduce the volumetric expansion due to gas energy release.This paper reports the results of laboratory experiments on cement-based high water content slurry having different water-cement ratios(W/C) to be used for coal injection. The results show that as the W/C increases, the mobility of the slurry and its setting time increase. The compressive strength and rupture strength, however, are reduced. Furthermore, high W/C grout shows early strength after 7 days, which can be 80% of its 14-day compressive strength. To achieve rapid setting and early strength, the addition of Na_2SiO_3has proven to give the best result, when the concentration of the additive is 3%. The initial and final setting times are 13 and 21 min shorter than samples without Na_2SiO_3, while the compressive strength is more than double. As a retarder, the initial setting time can be extended to 83 min when tartaric acid of 0.4% concentration is added. Through the orthogonal experiment, the optimum recipe of the new high water content slurry has been determined to be: W/C = 2, tartaric acid = 0.2%, Na_2SiO_3= 3%, and12% bentonite. Reinforcement by injection simulation experiments show that the grouting radius of the new slurry mix is 250 mm when the applied grouting pressure is 60 k Pa, 7-day rupture strength and compressive strength are 5.2 and 6.4 MPa, respectively, and are 37% and 88% higher than ordinary cement grout. It can be concluded that the newly developed slurry mix is more effective than the ordinary mix for reinforcing coal and controlling gas outburst.

Evolution algorithm for water storage forecasting response to climate change with little data sets:the Wolonghu Wetland,China

An attempt of applying a novel genetic programming(GP) technique,a new member of evolution algorithms,has been made to predict the water storage of Wolonghu wetland response to the climate change in northeastern part of China with little data set.Fourteen years(1993-2006) of annual water storage and climatic data set of the wetland were taken for model training and testing.The results of simulations and predictions illustrated a good fit between calculated water storage and observed values(MAPE=9.47,r=0.99).By comparison,a multilayer perceptron(MLP)(a popular artificial neural network model) method and a grey model(GM) with the same data set were applied for performances estimation.It was found that GP technique had better performances than the other two methods both in the simulation step and predicting phase and the results were analyzed and discussed.The case study confirmed that GP method is a promising way for wetland managers to make a quick estimation of fluctuations of water storage in some wetlands under condition of little data set.

Predicting Rainfall Using the Principles of Fuzzy Set Theory and Reliability Analysis

The paper presents occurrence of rainfall using principles of fuzzy set theory and principles of reliability analysis. Both the abstract and the rest of the paper are discussed from these two points of view. First, a fuzzy inference model for predicting rainfall using scan data from the USDA Soil Climate Analysis Network Station at Alabama Agricultural and Mechanical University (AAMU) campus for the year 2004 is presented. The model further reflects how an expert would perceive weather conditions and apply this knowledge before inferring a rainfall. Fuzzy variables were selected based on judging patterns in individual monthly graphs for 2003 and 2004 and the influence of different variables that caused rainfall. A decrease in temperature (TP) and an increase in wind speed (WS) when compared between the ith and (i ? 1)th day were found to have a positive relation with a rainfall (RF) occurrence in most cases. Therefore, TP and WS were used in the antecedent part of the production rules to predict rainfall (RF). Results of the model showed better performance when threshold values for 1) Relative Humidity (RH) of ith day;2) Humidity Increase (HI) between the ith and (i ? 1)th day;and 3) Product (P) of decrease in temperature (TP) and an increase in wind speed (WS) were introduced. The percentage of error was 12.35 when compared the calculated amount of rainfall with actual amount of rainfall. This is followed by prediction of rainfall using principles of reliability analysis. This is done by comparing theoretical probabilities with experimental probabilities for the occurrence of two main events, namely, Relative Humidity (RH) and Humidity Increase (HI) being in between specified threshold values. The experimental values of probability are falling in between μ ? σ and μ + σ for both RH and HI parameters, where μ is the mean value and σ is the standard deviation.