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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

中國之水利問題與農業

HE, Huikun 01 January 1950 (has links)
No description available.
72

Assessing the impact of human behaviour on reservoir system performance using dynamic co-evolution

Shanono, Nura Jafar January 2019 (has links)
A thesis submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Johannesburg, 2019 / Water resource systems management entails the coordination of hydrologic, infrastructural and human activities to plan, develop and supply water efficiently and sustainably. Hydrologic and human behaviour involve high levels of uncertainty and therefore pose unique challenges to water management. In reservoir yield and operation analysis, hydrologic uncertainties are usually incorporated in risk analysis using stochastically generated data but the impacts of human behaviour, although significant, are typically not incorporated. This study was therefore inspired by the need to quantitatively incorporate the impact of human behaviour into reservoir system performance thereby adding value to reservoir operational decision making. Unauthorised water abstraction is a significant human behaviour‐related activity and was therefore selected for this study. A socio‐hydrological model that simulates, couples and dynamically co‐evolves reservoir operation and human behaviour to assess the impact of unauthorised water abstractions on reservoir yield and operation was developed. The model quantitatively and stochastically relates fourstate drivers; hydrological state, users’ compliance, management competence and reservoir performance. Users’ compliance and management competence were modelled statistically by a 3‐parameter skew‐normal distribution and the propensity to unauthorised water abstraction (risk perception) was modelled as a function of users’ compliance, management competence and the hydrological state. The occurrence of unauthorised water abstraction was modelled stochastically by relating a sigmoidal function of risk perception to management competence. To assess the impact of human behaviour, nine scenarios derived from the different combinations of 3 categories of users’ compliance and management competence were developed and tested. The model was applied at a monthly time step to 2 hypothetical but realistic reservoir systems that were based on 90 years of hydrology and configuration of the Elands and the Olifants River reservoir systems in South Africa. Reservoir operation for maximizing yield was optimized by applying a simulation‐optimization approach that used 3 reservoir operating rule curves defined using trigonometric and simple linear functions. Shuffled complex evolution (SCE‐UA) was used for optimisation. The SCE‐UA was effective for the optimisation of the two reservoir systems when simple linear operating rules were applied. When trigonometric rule curves were applied, the SCE‐UA optimized the Elands system effectively but repeatedly terminated at a local optimum with 35% less yield for the larger Olifants system. It was therefore decided to mainly use the results from the linear rule curves to assess the effect of human behaviour on the performance of the two systems. Realistic time series of unauthorised water abstractions whose severity increased as users’ compliance and management competence declined were obtained. The losses in average yield for varying combinations of users’ compliance and management competence ranged from 2.3 to 9.2% and 5.3 to 11.5% for the Elands and Olifants systems respectively. The overall average loss in yield for all the nine scenarios were 5.8% and 8.9% for the Elands and Olifants River systems respectively. The losses in yield in individual years, however, varied considerably and during the drought years of the 90 year simulation period, they were much higher than the average losses. In one year, a 55% reduction in yield resulted from the scenario with the most adverse human behaviour. Optimised reservoir operating rule curves became more restrictive and lower reservoir storage trajectories were obtained as human behaviour declined. The modelling, therefore, revealed that yield reduced as human behaviour deteriorated and the losses obtained were reasonably close to the reported annual water loss due to unlawful uses of 6.4% in South Africa. The sensitive nature of the subject of study makes model verification on real‐life systems challenging. However, the research shows that practical reservoir system modelling that quantitatively incorporate the impact of human behaviour is a future possibility. / PH2020
73

Water resource decision making in the Western Cape system analysis

Van Zyl, Hugo January 1998 (has links)
Bibliography: pages 138-151. / Water resource decision making in Greater Cape Town is characterised by numerous, often conflicting goals. Among these are ensuring engineering feasibility and flexibility of supply, maximising water yield, minimising costs and minimising negative environmental and social impacts. Furthermore, in the face of ongoing development, decisions on future water supply options can be expected to increase in complexity along with the potential for conflict as natural resources become more scarce. In the present political climate, the need to transform public sector decision making into a democratic and transparent process has been recognised. Stakeholder groups need to be satisfied that their interests are taken into account in decision making and that decision makers are accountable for their actions. This thesis argues the case for the use of a formal framework to improve future decision making between water supply options in light of the above goals. After debating which type of framework would be most appropriate, the possible workings of a future system are briefly outlined.
74

INSTITUTIONAL MODELS FOR WATER RESOURCES ADMINISTRATION IN DEVELOPING COUNTRIES: CASE EXAMPLE, NIGERIA

Ajayi, Owolabi January 1982 (has links)
Assessment of water resources administration in Nigeria reveals gross inadequacies. The present decision-making framework for water resources administration is not expected to contribute much toward national development in the long run. Water institutions which should provide the means for implementing decisions can best be described as non-existent. Evaluation of water institutions found in the United States resulted in the development of three alternative institutional models of water resources administration, any one of which is recommended for adoption by Nigeria depending on the circumstances. Each of these three alternative models is characterized by significant citizen participation at all levels and at all stages of the decision-making process. One of the alternatives organizes water institutions by level of government, where the states are responsible for all aspects of water resources administration, as on the Colorado River Basin. Another alternative organizes water institutions on the basis of regional, basin-wide executive agencies, such as the Tennessee Valley Authority (TVA). A third alternative adopts a mixed strategy. Certain areas would have TVA-type executive agencies, while other areas would have no TVA-type agency, but the states would then be responsible for all aspects of water resources administration and development. This situation prevails throughout the United States. At the user level, the institutional framework of decision making for water resources administration provided by the special water districts found in the United States is recommended for adoption by Nigeria to fill a vacuum created at the interface of the water resources system and the social system. The choice of an overall institutional model for Nigeria will be determined by the final political map of the country in relation to the identified river basins. These alternative institutional models for water resources administration are also recommended for consideration by other developing countries.
75

Fluid boundaries : Southern California, Baja California, and the conflict over the Colorado River, 1848-1944 /

Boime, Eric I. January 2002 (has links)
Thesis (Ph. D.)--University of California, San Diego, 2002. / Vita. Includes bibliographical references (leaves 406-419).
76

The politics of water resource management in the Tucson, Arizona S.M.S.A.

Straayer, John A.,1939- January 1967 (has links)
The City of Tucson and surrounding metropolitan area are located in Pima County's Santa Cruz River Valley in arid Southern Arizona. The U. S. Bureau of Census defines the Tucson S. M. S. A. as including all of Pima County. The Tucson S. M. S. A. has experienced rapid population growth since World War II and, in January, 1967, had an estimated population of 335,000. Precipitation in the Santa Cruz Valley is slight, averaging only ten inches a year. Agricultural irrigation accounts for almost seventy per cent of all water use. The sole source of water in the Santa Cruz Valley, except for a little reuse of sewage effluent for irrigation, is groundwater. In recent decades the rate of groundwater withdrawal has exceeded natural recharge and the water table has steadily declined. It is the opinion of many that unless water is imported soon, a water shortage crisis may develop; but this is not unanimous opinion. Water management in the Santa Cruz Valley is highly decentralized. The City of Tucson, several school districts, an irrigation district, a federal airforce base, several industries, nearly 100 private water companies and hundreds of private individuals "mine" groundwater. Also, several state and local agencies perform regulatory functions related to water use, Many of those involved in Tucson area water management believe this decentralized pattern precludes proper water management and that it frustrates planning for assurance of an adequate, long-term water supply for the community. The study concludes that the Tucson area has a water shortage problem, but not a critical one, and that the pattern of water management is highly decentralized, Major reasons for this decentralization are that (1) water can be readily and easily obtained almost anywhere in the Santa Cruz Basin simply by sinking a well and withdrawing groundwater, and (2) that there is no state or local legislation which prevents individuals, corporations or governmental units from pumping when and where they choose. This decentralization leads to inter-governmental conflict, the unequal funding of research and development of future water sources, and, frequently to a lack of organizational concern about the problem. Water managing agencies tend to be "internally oriented,tt displaying more concern for short-run economic savings than for assurance of adequate, long-term water supply for the community. Several organizations, seeking to obtain water as inexpensively as possible, pump groundwater when and where they please, with no concern as to the impact their pumping may have on the water supply. Many contribute nothing toward research and development of future water sources. Further, organizations tend to blame one another for the water problem. Arizona water law and a lack of water management direction at the state level also frustrate planning for assurance of a long-term water supply for the area. The study suggests that, at both the state and local levels, water management be centralized under the direction of the City of Tucson, Pima County, through creation of a water district, or through institutionalization of inter-governmental cooperation. Changes in. the Arizona water code are urged as is early development of new water sources. A critical examination of the merits of the proposed Central Arizona Project is suggested. It is concluded that the suggestions made in the study are not immediately politically feasible, but that they will be both politically feasible and necessary within a decade or two.
77

Water for weststate, U.S.A.: the association in the politics of water resource development.

Eiselein, E. B.(Eddie Bill),1942- January 1969 (has links)
Water resource development in the American West is partially dependent upon a political process of decision-making. Within Weststate, U.S.A., this political process is viewed as a system composed of various social units and it is examined through the activities of one type of social unit--the formal voluntary association. Eight associations were studied over a period of eighteen months. Each of the associations was examined with regard to its activities in seven issues of water resource development, the internal organization of the association, the relationship of the association with the water-oriented power structure of the state, the interrelationships with the other social units of the system, the problems of associational success and failure, and function of the association in the internal maintenance of the system and its output. It was found that the associations were not totally independent of one another nor of the other social units in the system. Rather, they were observed to be connected in varying degrees of elasticity through the sharing of personnel, interlocking directorates, the role-positions of expert and observer, and indirect ties via intermediary social units. Within the system one of the basic functions of the associations was conflict reduction. Associations were found to decrease the potential for cooperation. The associations also served as conflict creators by acting as autonomous bases of countervailance. The distribution of power throughout the system, and particularly between the "public" and "private" sectors, was another function of the association. This was usually done in three ways: (1) coordinate, usually related to a task-specific division of power, (2) subordinate, usually tied to the need for grassroots support for agency programs, and (3) superordinate, which usually involved a clientele's control of a service agency. Another power distributing function of the associations was to act as a "drain" to draw power away from the system by arousing the masses and having them rescind the proxies of power which they had given de facto to the System. The association also functioned as change inducers by providing an informal and nonpublic setting for compromise and decision-making, by reducing conflict, and by distributing power. Conversely, the associations also functioned to prevent changes by acting as independent bases of countervailance and by draining power from the system.
78

A decision-aiding model for planning optimal resource allocation of water basins.

Bartlett, Ellsworth Thomas,1943- January 1974 (has links)
Because of increasing and often conflicting and changing demands, natural resource managers must decide what products to produce, what quantity of each to produce, and how to allocate the resources to produce those products. It is a nearly impossible task for a manager to quantify, analyze, and compare all the alternatives. Decision-aiding models, such as the water basin model, provide a mechanism capable of handling extremely complex problems, while at the same time giving the resource manager a quantified basis on which to make decisions. The water basin model employs two methods of system analysis for developing optimal management plans. These two methods, linear programming and dynamic programming, are used in a hierarchial combination for comparing alternatives on water basins. The model links both on- and off-site uses of basins in a rational combination of levels. The multilevel model considers the initial condition and potential of vegetation, climate, and soils at the lowest level and proceeds through a hierarchial scheme to arrive at allocation of budgetary resources among response units and subwatersheds. For an array of basin investment levels, the guide indicates how water should be allocated among onand off-site uses using a dynamic program, how the investment should be allocated among subwatersheds using a dynamic program, and how the investment should be allocated among development alternatives on each subwatershed using a linear program. A test run of the model was made on an existing basin in northern Arizona using forage grazing as the on-site use and water for irrigation as the off-site use. Basic inventory data obtained from the Bureau of Land Management provided input for determining ecologic and hydrologic response to on-site management. The sensitivity of plans to onsite benefits from forage harvest was examined and showed that direct benefits to the federal government do not justify development expense. However, on-site development was indicated when benefits were based on the corresponding value that private firms give for grazing forage. Even though the water basin model is confined to a single objective function or goal, it provides a rational method for aiding the decision process that is necessary for the efficient and proper use of our natural resources. The model serves three useful functions: (1) provides preliminary guides for managers, (2) brings to light future research needs, and (3) provides impetus for developing better models. In the use of this model, it must be remembered that models can only serve as management tools. Models, no matter how complex and detailed, will always be abstractions of the real world on which human managers must make the final decisions.
79

Cognitive strawman : public input to a water resource planning system

Judge, Robert Michael,1941- January 1975 (has links)
The purpose of this research is to develop an information system to input public values into the planning and evaluation process. A hierarchy of goals is developed and disaggregated until terms meaningful to the general public, and describing the state of the world, can be input to the disaggregation. The relationship between the planning process and the public values expressed by the terms describing the state of the world is discussed. A function is hypothesized to quantify one measure of perceived well-being. The application of the quantifying function to the general public and to sub-groups of the general public is discussed. The conventional scaling techniques of ranking and rating are discussed and compared with a general allocation technique and other psychologic scaling methods to estimate the parameters of the quantifying function. A power function is tested against the satisfaction ratings given a group of samples of water of varying clarity. The parameters thus estimated are significantly greater than zero. The general allocation technique was used to recover the parameters of the quantifying function and compared to the parameters estimated by the regression analysis. The general allocation technique showed promise as a means of recovering the public values. The general allocation technique was then applied to determine the goal and sub-goal preferences of subjects in Arizona and the Rio Grande Valley of New Mexico. The research indicates that community values can be input to the planning process by use of the disaggregated goal structure and the quantifying function. The general allocation technique, used in a mail survey, shows promise as a means of recovering community preferences. The disaggregation of community goals may provide a means of linking the technical criteria of the professional and the values and goals of the general public. The development of a hierarchy of goals may provide an additional tool for decision makers and professionals in their analysis of public values.
80

Computerized water distribution management for the Upper Pampanga River Project, Philippines

Aldovino, Lino Pineda,1945- January 1977 (has links)
This study is concerned with the development of a model for realtime water distribution management for rice crop production in the Upper Pampanga River Project (Philippines). The model utilizes a management technique which considers water distribution at the farm level on a system-wide basis under the constraints of the present users and the physical system situations. The intent of the project is to rely as much as possible on the available uncontrolled streamflows and rainfall during the wet season in order to minimize releases from the Pantabangan reservoir, and thus conserve most of the impounded water for irrigation during the dry season. A computerized model which incorporates a parameter prediction-correction technique is developed for calculating the daily water scheduling for the entire canal network of the UPRP. To determine how much water is needed, a daily water budget at each of the 2,216 rotation areas is performed in conjunction with the daily predicted uncontrolled streamflows, rainfall, varying water requirement, and water status at the farm level. Subsequent delivery correction schedules are determined based on the degree of the prediction error. Studies were conducted for the determination of the appropriate rainfall prediction scheme used in the scheduling model. Selection of the scheme was done through simulation of field operations at the farm level and by the application of the rainfall-use efficiency criterion. Time lags along the Pampanga River and the canal network were analyzed to determine the possibility of supplying the entire network from the Pantabangan Dam within 24 hours. The idealized solution of the problem of inequitable distribution of water within a rotation unit is also presented. The ability of the model to provide situation-and-user-oriented guidelines for water distribution activities is demonstrated.

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