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1.
Conclusions  
1.  The off-design operating regime of the Chirkey hydrostation with difficulties in producing electricity and with long periods of high upper pool levels under conditions of seismic activity negatively affects the reliability of the surrounding rock mass and should be brought into correspondence with the design.
2.  Long and nonuniform operation of the Chirkey hydrostation outlet in 1997 showed sufficient reliability and efficiency of the structures, but activated negative processes in the surrounding rocks masses. The rupture of two rock bolts supporting the unstable mass on the left bank and increase of the rate of settlement of the left wall of the canyon are a warning signal. This requires a thorough examination of all support members and development of outlet operating rules.
3.  The consequences of the operation of the outlet for the reliability and stress-strain state of the dam sould be specially and comprehensively studied and analyzed. It is urgently required to determine the forces in the rock bolts supporting the unstable mass, to determine the magnitude and places of maximum stresses in the dam, and to monitor the rate of movement of the left-bank slope.
4.  It is urgently necessary to organize appropriate seismometric monitoring on the dam and to obtain daily (weekly) bulletins of the Dubka seismic station and periodic reports of the OMP DNTs on the seismological situation in the region.
5.  Before organizing seismometric monitoring on the dam or geodynamic test area of the Center of the Geodynamic Observation Service in the Electric Power Industry, it is necessary to use the earthquake prediction method of the Joint Institute of Physics of the Earth with the help of the dam's existing measuring systems. For this purpose it is advisable to automate the reversed plump lines by the “Sibgeoinform” or DIGéS (Diagnosis of Hydraulic, Power, and Other Essential Structures) method and to increase the accuracy and frequency of seepage observation.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 7, pp. 6–10, July, 1998.  相似文献   

2.
Confronted with the problem of overflows from its combined sewer system into the River Seine during rainfall, the Department of the Hauts de Seine (which covers some thirty urban districts on the west side of Paris) has decided to implement the real time control of its sewer system. To initiate this plan, as the town of Boulogne Billancourt seemed to be a particularly favourable site for the use of such techniques, a project to control its sewer system in real time has been implemented within the scope of the SPRINT 226 programme financed by the European Community.The preliminary studies, based on a MOUSE computer model of the sewer system, showed that the real time control of the sewer network under study had a high potential benefit, since it would allow an 80% reduction of the volumes of waste water discharged into the Seine annually in the study zone. Following on from these encouraging results, the installation of a complete real time control system was set in hand. The system, at present undergoing testing and evaluation, consists principally of a MOUSE ON LINE real time model and a system for forecasting rainfall by means of radar images.  相似文献   

3.
1.  The hydraulic projects awarded prizes by the Council of Ministers of the USSR in 1976 solve a set of critical national-economic problems and are distinguished by high cost effectiveness.
2.  Structures distinguished by originality and progressiveness of technical solutions, which ensure their reliable operation, have been constructed as the result of a set of scientific-research and design studies. This was made possible only by the close creative understanding and interaction between the scientific-research, planning, construction, and operating organizations.
3.  In building hydraulic structures, all the more attention is focused on industrial aesthetics. The architectural-planning solutions of the prizewinning projects are new, represent examples of the progressive development of industrial architecture, and have obtained widespread public recognition.
4.  The bold and economic solutions relative to the organization of the passage of flood waters over incomplete structures merit attention; this makes it possible to reduce the volumes of the enclosing foundation pits of the cofferdams, or eliminate them entirely.
5.  The experience gained with the design and construction of the prizewinning projects should be studied in detail and publicized for purposes of utilization in subsequent design and construction.
  相似文献   

4.
The current paper aims at analyzing the behavior of monthly precipitation in the Brazilian and Bolivian parts of the basin of the Madeira river, one of the most important sub-basins of the Amazon basin. Both parts account for 93 % of its total, and studies on this topic are lacking. The research was based on data from 41 rainfall stations considering a historic series from 1978 to 1998, which encompasses two of the largest El Niño events (1982–1983 and 1997–1998), hence its influence on the precipitation of the region was assessed as well. To study precipitation behavior, rainfall was regionalized using data clustering methods (Ward and K-means), with the basin being divided into five regions of homogeneous rainfall. Both methods were applied to the regions and showed similar results, providing a higher reliability for the clusters obtained. The results of the analysis show the homogeneous regions of the basin, the spatial variability of precipitation, seasonality and the influence of the phenomenon on the region.  相似文献   

5.
In order to raise the reliability of operation of the system of end glands of K-300-240 turbines at the Konakovo State Regional Power Plant (Konakovskaya GRÉS), the system for feeding steam to the end glands of high-pressure and intermediate-pressure cylinders has been updated. The updating included reconstruction of chimneys at the suggestion of the Komtek-Énergoservis Co. and feeding of cooling steam to the zone of the third compartment of the front end gland of the intermediate-pressure cylinder. The measures taken increased the reliability of operation of the system of turbine glands, eliminated oil watering due to steaming, and reduced the temperature deformations of chimney gland yokes.  相似文献   

6.
Abstract

Discharge records originating from 78 rivers within the Asia-Pacific region are used to assess a possible relationship between a temporal El Niño-Southern Oscillation (ENSO) Index and regional discharges of rivers. The rivers selected have long monthly discharge series and are geographically distributed throughout the whole region. Analyses of variance are used to identify the sub-regions most teleconnected to the ENSO signal. Composite analyses show the temporal patterns of the relationships between river discharge and the ENSO signal and the possible presence of a time lagged relationship. The analyses show that the rivers of the Oceania-Pacific region are the most affected and that a majority of rivers show a similar temporal pattern, thus allowing the construction of a regional composite streamflow index. The temporal patterns of the identified relationships demonstrate the possibility of forecasting the occurrence of abnormally high or low flows (floods/droughts) months ahead of time.  相似文献   

7.
This paper describes the use of the dual isotope method involving δ(15)N and δ(18)O measurements of dissolved nitrates to assess the origin and fate of groundwater nitrate at the Klju? groundwater source, Serbia. A sampling campaign was conducted in September 2007 during flow conditions obtaining groundwater from observation wells and river water fed by a shallow aquifer hosted in alluvial (sandy-gravel) sediments. Nitrate isotope ratios ranged from +5.3 to +16.9‰ and δ(18)O(NO(3)) values varied from -2.3 to +5.0‰. Two major contamination sources were identified with isotopic compositions characteristic for nitrate derived from nitrification of soil organic nitrogen (+5.3 to +7.8‰ for δ(15)N) resulting in nitrate concentrations of 33.6 and 78.8 mg/L and nitrate derived from animal wastes or human sewage, e.g. via septic systems, yielding δ(15)N values of +9.9 to +11.9‰ and elevated nitrate concentrations of 31.2-245.8 mg/L. The occurrence of nitrification and denitrification was also revealed based on concentration and isotope data for dissolved nitrate.  相似文献   

8.
1 IntroductionThe Tidal Thames is a well mixed estuary stretching some140 km from Teddington to the North Sea , which provideshabitats for both resident and migrant fish species . With tidalwater enteringfromthe ocean and fresh water flowingfromtheland ,t…  相似文献   

9.
1 StudyAreasandStudyMethodology1.1 SamplingAreasandSampleTypesAllthesampleswerecollectedfrommainstemcross-sectionsandnearshorewatersof 2 2majorcityriverreachesofPanzhihua ,Yibin ,Luzhou ,Chongqing ,Fuling ,Wanx ian ,Yichang ,Shashi,Yueyang ,Wuhan ,Ezhou ,Huang shi,J…  相似文献   

10.
ABSTRACT

It is argued that the establishment of tradable water rights will play an important role in increasing productivity and sustainability of water use in developing countries. Due to economic growth, scarcity is expected to be conducive to water market development. This article presents the potential for and feasibility of markets in water rights in Jordan through a comparative study of Chile, Mexico, and California. Many lessons were learned from the experiences of those countries concerning water markets. The transformation of these lessons to the Jordanian context is faced with some fundamental challenges in terms of water legislation, institutional structure, and data. Water legislation must deal with externalities, dispute, and third-party effect. Adopting a new water act and review of water laws is essential for better water resources management and assured public input and feedback. Market oriented policy should be introduced only on a pilot basis in terms of pricing. Policy makers believe that dealing with future water scarcity in Jordan will be achieved through better management and utilization of water using both conventional and nonconventional sources. Moreover; policy makers and farmers in Jordan expressed strong reservations on intersectoral water transfers because of the importance of water to the Jordanian economy.  相似文献   

11.
In 2007, the six riparian countries of the Volta Basin adopted the Convention on the Status of the Volta River and the Establishment of Volta Basin Authority (Volta Basin Convention). This legal framework is strongly inspired by the United Nations Convention on the Law of Non-navigational Uses of International Watercourses (UNWC). However, the Volta Basin Convention merely states the major international river management principles without specifying either the terms or the procedures for their implementation. This article examines the potential contribution of the UNWC provisions to the development of a water charter.  相似文献   

12.
Conclusions An experimental check of various low specific-speed pumps showed that on changing the geometry of the vaning of the impeller, in conformity with the recommendations [1], the main feature of which is an increase of the outlet angles of the vanes to values 90°2130° and installation of short intermediate vanes in the passages between the main vanes, the head increases considerably without a decrease of pump efficiency.For centrifugal pumps with a volute and diffuser whose impellers have a different number of main vanes, the most rational is the installation of three intermediate vanes in each vane passage with a change in the direction of the flow by the main vane toward an increase of the outlet angle on diameter D2=0.5–0.65D3 for fecal pumps and pumps with short vanes.The use of the new impeller design is especially effective for high rotative-speed pumps. For multistage submersible pumps with a guide-vane apparatus at the inlet and axial outlet, the optimal variant is the installation of one intermediate vane with a start of the change in the flow direction D3=0.63D2.In conclusion, it is necessary to note that all tests were conducted without modifying the casing and branch pipes, which leaves room for a further increase of the head developed by pumps with the new type of impeller.Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 5, pp. 21–25, May, 1982.  相似文献   

13.
The 3-D flow fields and power consumption in a vessel stirred by multistage Scaba 6SRGT impeller have been investigated. The Xanthan gum solutions in water were used, which have a shear thinning behavior with yield stress. This study was carried out with the help of a CFD package(CFX 13.0, Ansys Inc.) which is based on the finite volume method to solve the momentum equations. The effects of stirring rate, fluid rheology, impeller number, impeller location and vessel size on the performance of such stirred system are presented. To validate the CFD model, our predicted results have been compared with other literature data and a satisfactory agreement has been found.  相似文献   

14.
Integrating seasonal patterns of water availability and land-use/land-cover change is crucial in watershed planning. Often, these are not considered under hydrological extremes affecting decision making. This article presents results from a multi-site, nested catchment experiment carried out during a dry period in the Cantareira Water Supply System, South-East Brazil, linking quali-quantitative freshwater monitoring to land-use/land-cover change. Results from 17 catchments show regional behaviour for nitrate loads and drainage areas (0.66–925 km2). An inverse correlation between forest cover and water yield was observed. Despite forest growth in spatial extent, nutrient loads showed potential hazards for water security.  相似文献   

15.
Results of the use of automatic hydrogen-content meter for controlling the parameter of hydrogen in the primary coolant circuit of the Kola nuclear power plant are presented. It is shown that the correlation between the hydrogen parameter in the coolant and the hydrazine parameter in the makeup water can be used for controlling the water chemistry of the primary coolant system, which should make it possible to optimize the water chemistry at different power levelsTranslated from Élektricheskie Stantsii, No. 12, December 2004, pp. 31 – 33.  相似文献   

16.
Aggradation of channel on the lower reaches of the Yellow River is mainly governed by the regimen of river discharge and sediment delivered from upstream. In the long run, channel accretion exhibits alternate increase and decrease, somewhat periodic in nature.The long-term average annual deposition is something like 300 million tons. Besides the aforesaid factor affecting scouring and depositing along the river channel along the lower reaches, there are also the following factors of influence: fluvial processes and changes in river bed in previous stages, operation of Sanmenxia Reservoir in regulating floodwater and sediment delivery, as well as conditions at the river mouth. After undergoing 3 consecutive periods of accretion-degradation-accretion, and being subjected to different measures to cope with the problem at different times, adapting to the actual condition, there is now only accretion to limited extent above Jiahetan and .below Aishan, most of the deposits being laid in the intermedite section. The distribution of the deposits in the crosswise direction is related to overflowing onto the floodplains, the duration, and the condition of levees there (to protect the farmland on the floodplains from ordinary floods). During the period from 1950 to 1983, a total of about 5 biIlion tons of sediment deposited on the floodplains on the lower reaches, comprising 70% of the entire volume of deposition, distributed unevenly though, mainly outside the area sheltered by the levees, effecting in an increase in transverse slope of the channel. In some sections, "suspended river" was formed within the already "suspended" river (river bed lying above the land surface behind the dykes).Sequence of years of observation in the fifties was chosen and the regulating effect of the Longyangxia, Liujiaxia and Sanmenxia and other reservoirs is also taken into account. In the 12 years from 1984 to 1995, average annual runoff on the lower reaches of the Yellow River will be 38.8 billion m~3, carrying 1.61 billion tons of sediment each year. Through comprehensive analysis of the observed data, it has been found that the avergae yearly deposition on the lower reaches of the Yellow River will be something like 400 million tons for the same period, mostly in the reaches between Jiahetan and Aishan. Channel accretion in the reaches from Aishan to Lijin will be somewhat on the ascent.  相似文献   

17.
General Thoughts on Water Resources Devel-opment In Western Regions In order to realize the objective of having abreakthrough in construction of infrastructure facilitiesand ecological environment, Ministry of Water Re-sources has proposed the Guiding Principles of WaterResources Development in West Regions as follows:  相似文献   

18.
This study applies input-output analysis to evaluate and trace Saudi Arabia’s virtual water exports arising from exports of agricultural products. Saudi Arabia’s total virtual exports in 2011 were around 2.42 km3, mainly to neighbouring Arab countries. This amount is enough to meet the water demand of the country’s entire population. Agricultural exports seem economically beneficial only because they rely on groundwater; however, since the indirect cost of desalinating equivalent amounts of water for domestic purposes is much higher, a better strategy would have been to direct those water resources towards domestic needs.  相似文献   

19.
The hydraulic projects, such as reservoirs, ponds, and paddy fields, have a marked influence on the generation of floods, causing a number of difficulties where hydrological forecasting is concerned. To consider the influence of the hydraulic projects in hydrological forecasting, a modified TOPMODEL is presented in the paper, based on the simulation rules of the aggregate reservoir’s retaining and discharging (ARRD). In the new purposed model, termed as ARRD-TOPMODEL, the hydraulic projects are first aggregated as an equivalent reservoir, then the simulation rules of the aggregate reservoir’s retaining and discharging are determined, finally, the simulation rules are combined with an original TOPMODEL model calibrated using the floods not influenced by the hydraulic projects for flood forecasting. The ARRD-TOPMODEL was tested on the upstream of Wudaogou station basin in Northeast China. The results show that compared to the original model, the qualified rate (i.e., the ratio of the number of floods that meet acceptable criteria and the total number of floods) of runoff forecasting was increased from 73% to 100%. The problems that the overestimation of the runoff at beginning of flood season and after a long drought, as well as that the underestimation of the large flood in middle flood season are both solved, and the flood processes predicted by the new model are more consistent with the observed ones. All of these demonstrate that the newly developed model is superior to the original one and the simulation rules of the aggregate reservoir’s retaining and discharging are capable of accurately accounting for the influence of the hydraulic projects on the floods.  相似文献   

20.
1.  Alteration of the follow-up circuit of the SC in the type ÉGR-M SG during operation of the units in a group control system provides the possibility of smooth transfer of the unit out of the APGC system, which increases the operating reliability of the APGC system in an overcurrent control regime and in eliminating emergency situations.
2.  After an additional check, the alteration of the follow-up circuit of the SC can be used for a second modification of the type ÉGR-2M governors of turbines.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 1, pp. 33–35, January, 1989.  相似文献   

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