5,191 research outputs found
Investigations on the Impacts of China's Rural Water Policies: From Efficiency and Equity Perspectives
China’s water resources are scarce. Given its limited water resource, policies in China have been traditionally focused on meeting sectoral demands for water by increasing the supply rather than managing demand. However, effective water resource policies that focus on demand management and encourage efficient water use remain the main weakness of China’s water policy. Main potential for efficiency gain is the agricultural sector, which accounts for 65 percent of the nation’s total water withdrawals. Due to major inefficiencies in irrigation water systems only about 45 percent of water withdrawals for agriculture are actually used by farmers to irrigate their crops. In addition to inefficiencies, the equity of the agricultural water policies is questionable, That is, existing policies lead to an inequitable allocation across different parts of the basin and within a given irrigation system. Designing policies that are both efficient and equitable is a challenge that has yet to be met. In this paper we explore the potential for an improvement in policies that address water use efficiency and equity in one of China’s rural regions. A spatial water allocation model is employed to maximize water use efficiency at both public water conveyance system and private on-farm water use in one of the irrigation districts in Northwest China’s Shaanxi Province. First-hand data which were collected from our field survey will be used in the water allocation model. Water is provided by a government authority via a public canal to farmers. Water use efficiency is modeled along with efficient and optimal cropping patterns to be endogenously determined by the decision makers in the region. The public water conveyance system has a given efficiency that can be improved with investment to reduce deep percolation. This can be done either by farmers or through cost sharing arrangements between farmers and the government. Pumping water from the canal is not regulated and sequencing of the farmers along the canal dictates the amount of water to be used by each farmer. Under the unregulated case equity may be the lowest, where the upstream users may pump unrestricted amounts and the downstream users may use the remainder. Increased efficiency of the public canal may lead to more available water to the upstream users. In a parallel venue, when on-farm efficiency is improved, less water is returned to the aquifer, leaving less water as a return flow to be available to the downstream users. Hence equity is always an issue whenever efficiency is improved. Specifically in our study area farmers’ lands are covered by one irrigation authority and situated along a canal. All farmers have access to public canal water and groundwater. For those situated at plain area, where winter wheat is grown, they have better access to abundant and cheap public canal water. For those farmers living at hilly, higher elevation area, where apple production is dominating, they get water from public canal with a higher price of about 40% compared with the price their counterparts at the plain area due to an additional (stage 1 station) lift-height pumping cost. At last, water will be delivered to mountainous area where corn is grown. A stage 2 lift-height pumping station lifts the water again to irrigate the corn’s fields. Consequently the water price is doubled as compared to the original water price at the plain area. Corn needs less water than wheat and apple. Farmers may reduce their water costs either by reducing canal water application, and groundwater pumping, or by dry land farming. A canal controller or examiner will be introduced to the canal management. By doing so, the policy impacts of regulated and unregulated cases are analyzed. Our framework includes water use efficiency, water pricing and various policy interventions that are aimed at both increasing total welfare and improve income distribution along the canal. We show how important it is for the public agency and the private users to cooperate in order to achieve water use efficiency and equity within the irrigation network. Policies include various water pricing schemes, the unregulated case, increased monitoring and enforcement of various water allocation methods, cost sharing arrangements, side payments, and trade in water rights (that will be allocated by the government). A General Algebraic Modelling System (GAMS) is employed to achieve the optimization process under the water system constraints and other policy regulation constraints.Water efficiency, Equity, China’s rural water management, Environmental Economics and Policy,
Application of a Spatial Water Model in a Chinese Watershed
China's fast growing economy has brought some environmental problems, especially in water administration. Inefficiencies in irrigation activities have created severe negative effects to the environment of rural communities, and the more serious water shortages hamper food production, too. Major questions at hand are, how to improve water use efficiency, to reduce negative external effects, to optimize water allocation in agriculture, to invest in water saving technologies, and to assure more water for high value added agriculture. This paper investigates the impacts of irrigation technologies and investments in water saving on the rural economy and the environment. By taking into account individual farmers' inclination to adopt modern water-saving technologies and governments willingness to improve public water transit systems, we optimize water use in a Chinese watershed. The main contribution is a model that shows how to optimize spatial allocation and adoption of irrigation technology given farm and investment costs. The paper employs a mathematical, spatial programming model using GAMS for optimization. It shows the importance of water pricing and discusses various policy measures such as pricing and public conveyance. The model results are of value for policy makers and project managers to allocate water more efficiently, to optimize irrigation projects, and to provide references for farmers in applying water conservation technologies.a spatial model, water use efficiency, adoption of irrigation technology, technology, Resource /Energy Economics and Policy, C61, Q25, Q56,
Exploring multi-level factors predicting the role distribution of decision on transportation and destination of family vacations: An East Asian perspective.
Genetic algorithms in timetabling and scheduling
Thio thesis investigates the use of genetic algorithms (GAs) for solving a range of
timetabling and scheduling problems. Such problems arc very hard in general, and
GAs offer a useful and successful alternative to existing techniques.A framework is presented for GAs to solve modular timetabling problems in edu¬
cational institutions. The approach involves three components: declaring problemspecific
constraints, constructing a problem specific evaluation function and using a
problem-independent GA to attempt to solve the problem. Successful results are
demonstrated and a general analysis of the reliability and robustness of the approach is
conducted. The basic approach can readily handle a wide variety of general timetabling
problem constraints, and is therefore likely to be of great practical usefulness (indeed,
an earlier version is already in use). The approach rclicG for its success on the use of
specially designed mutation operators which greatly improve upon the performance of
a GA with standard operators.A framework for GAs in job shop and open shop scheduling is also presented. One
of the key aspects of this approach is the use of specially designed representations
for such scheduling problems. The representations implicitly encode a schedule by
encoding instructions for a schedule builder. The general robustness of this approach
is demonstrated with respect to experiments on a range of widely-used benchmark
problems involving many different schedule quality criteria. When compared against
a variety of common heuristic search approaches, the GA approach is clearly the most
successful method overall. An extension to the representation, in which choices of
heuristic for the schedule builder arc also incorporated in the chromosome, iG found to
lead to new best results on the makespan for some well known benchmark open shop
scheduling problems. The general approach is also shown to be readily extendable to
rescheduling and dynamic scheduling
Using Creative Methodology to Explore Life-time LGBTQ+ Love and Relationship Experiences:Towards Positive Intergenerational Exchange
Bis(quinolin-8-ol)silver(I) 2-hydroxy-3,5-dinitrobenzoate
The title compound, [Ag(C9H7NO)2](C7H3N2O7), was prepared from 3,5-dinitrosalicylic acid (DNS), quinolin-8-ol and AgNO3. The AgI atom is coordinated by two N atoms and two O atoms from two quinolin-8-ols in a roughly planar [maximum deviation = 0.223 (2) Å] environment. The two quinolin-8-ol ligands are bent slightly with respect to each other, making a dihedral angle of 9.55 (9)°. The DNS anion interacts with the silver complex through O—H⋯O hydrogen bond
2-(1H-Benzotriazol-1-yl)-1-(4-ethylbenzoyl)ethyl 2-chlorobenzoate
In the crystal structure of the title compound, C24H20ClN3O3, weak intermolecular C—H⋯O hydrogen bonds link the molecules into chains extended along the a axis. The crystal studied was found to be an inversion twin
2-(1H-Benzotriazol-1-yl)-1-(2-fluorobenzoyl)ethyl 4-methylbenzoate
In the crystal structure of the title compound, C23H18FN3O3, intermolecular C—H⋯N hydrogen bonds link the molecules into chains extended along the c axis. The packing is further stabilized by weak C—H⋯O and C—H⋯F interactions. The F atom is disordered over two equally occupied 1- and 5-positions of the benzene ring
5-(2-Fluorobenzylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione
The title compound, C13H11FO4, was prepared by the reaction of 2,2-dimethyl-1,3-dioxane-4,6-dione and 2-fluorobenzaldehyde in ethanol. In the crystal structure, molecules are linked into chains by weak intermolecular C—H⋯O hydrogen bonds
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