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991.
Manpreet Singh UCOE Manjeet Singh Patterh UCOE 《Information Security Journal: A Global Perspective》2013,22(6):332-343
ABSTRACT It is difficult to define reliable security policy components that should be applied to validate a secure computing environment. The job gets further complicated when one has to deal with multiple policies in single computing environment. This paper demonstrates how we can overcome the difficulties of defining reliable security components by using evaluation criteria. In this paper we use common criteria to derive the security functional components for a multipolicy-based network computing environment. In the verification process, the derived policy components are related to the specific security objectives of the network communication environment. The evidence listed in the case study supports the claims that the proposed network security policy interpretation framework is a complete and cohesive set of requirements. 相似文献
992.
Roberto D. Ponce Felipe Vásquez Alejandra Stehr Patrick Debels Carlos Orihuela 《Water Resources Management》2011,25(10):2449-2466
This paper presents a contingent valuation study concerning landscape impacts generated by the construction of one dam (Baker
1) of the HIDROAYSEN hydropower project located in the Chilean Patagonia. A survey was used to collect information about citizens’
opinions towards the hydropower project in four major cities in Chile. Specifically, a One-and-One-Half-Bound (OOHB) willingness
to pay eliciting format was applied to capture citizens’ WTP. The economic loss, associated to the landscape impacts for people
living in urban areas of the country, is found to be approximately US$ 205 million, which is nearly 28% of the total investment.
Our results also show that the cities’ distance from the dam affects citizens’ willingness to pay. 相似文献
993.
Qiang Zhang Ben-De Wang Bin He Yong Peng Ming-Lei Ren 《Water Resources Management》2011,25(11):2683-2703
High accuracy forecasting of medium and long-term hydrological runoff is beneficial to reservoir operation and management.
A hybrid model is proposed for medium and long-term hydrological forecasting in this paper. The hybrid model consists of two
methods, Singular Spectrum Analysis (SSA) and Auto Regressive Integrated Moving Average (ARIMA). In this model, the time series
of annual runoff are first decomposed into several sub-series corresponding to some tendentious and periodic motions by using
SSA and then each sub-series is predicted, respectively, through an appropriate ARIMA model, and lastly a correction procedure
is conducted for the sum of the prediction results to ensure the superposed residual to be a pure random series. The annual
runoff data of two reservoirs in China are analyzed as case studies. The results have been compared with the predictions made
by ARIMA and Singular Spectrum Analysis-Linear Recurrent Formulae (SSA-LRF). It is shown that hybrid model has the best performance. 相似文献
994.
Assessment of Sustainable Yield of Karst Water in Huaibei,China 总被引:2,自引:1,他引:1
Dan Yin Longcang Shu Xunhong Chen Zhenlong Wang Mokhatar Eisa Mohammed 《Water Resources Management》2011,25(1):287-300
This paper presents the assessment of sustainable yield in the Huaibei karst water area of Anhui province, China. A review
of sustainable yield definition is introduced first in this paper, and sustainable development in karst areas is more difficult
due to the complicated hydrogeologic conditions. General hydrogeology of the study area is provided to characterize hydraulic
connections between the karst aquifer and an overlying porous aquifer. Groundwater level declines continuously due to over-exploitation
of the karst groundwater, and two layers of groundwater dropping funnel were formed in Huaibei. These problems not only threaten
the eco-geo-environment, but also compromise the water utilization which depends on the shallow porous water. A “critical
water level” is proposed in this study to assess the sustainable yield, and it is determined by the historical exploitation
data which represent the relationship between the karst water and the shallow porous water uses. A three layer Artificial
Neural Network (ANN) model is used to understand the complex relationship of the karst water level and its influencing factors.
Precipitation, exploitation and water level of latest period are chosen as the input nodes, seasonal records of water level
are simulated by the ANN model. The sustainable yield is calculated by the trail-and-error adjusting method, and is equal
to the pumping rate when the “critical water level” is maintained. The rate of 30.05 MCM/a is the sustainable yield for the
Huaibei karst area in 2008, and it is less than the real pumping rate of 35.92 MCM/a. This assessment is meaningful to the
management for the Huaibei karst water. 相似文献
995.
Optimizing Safe Yield Policy Implementation 总被引:1,自引:1,他引:0
The presented method enhances groundwater-mandated safe yield management. It is useful for settings that prevent sustained
yield or integrated management. To protect hydraulically connected surface water rights, the Utah government’s Cache Valley
groundwater management plan proposes that total pumping increase not exceed 84,431 m3/day. To determine how best to spatially distribute additional allowable pumping, stakeholders quantified limits defining
acceptable impacts on selected water resource indicators. A new simulation–optimization (S–O) algorithm used these limits
while computing optimal spatially distributed perennial yield or safe yield groundwater pumping extraction strategies. The
limits prevent unacceptable decreases in: head and net flow between aquifer and surface waters (rivers, surface/subsurface
drains, springs, lakes). The optimization objective function maximizes weighted pumping to provide water for 18 growing municipalities.
For 16 perennial yield scenarios, computed optimal pumping increases differ in protectiveness toward senior water rights,
and range from 16% to 103% of the state plan-proposed increase. Implementing a protective strategy would achieve 90% of the
storage changes needed to reach equilibrium within 23 years. Indicator potentiometric heads would reach equilibrium within
10–40 years. At equilibrium, an optimal Cache Valley perennial yield strategy acceptably minimizes net annual non-pumping
discharges. By comparison, multi-period 20-year transient groundwater mining optimizations allow more pumping in early years.
Pumping then must decline to satisfy seepage and head constraints through year 20. Adverse seepage impact would increase for
years thereafter. For situations governed by safe or perennial yield policy, equilibrium-based (steady-state) optimization
is very useful. It effectively develops optimal perennial yield strategies. 相似文献
996.
Design of Barrages with Genetic Algorithm Based Embedded Simulation Optimization Approach 总被引:2,自引:2,他引:0
Raj Mohan Singh 《Water Resources Management》2011,25(2):409-429
Barrages are hydraulic structures constructed across rivers to divert flow into irrigation canals or power generation channels.
The most of these structures are founded on permeable foundation. The optimum cost of these structures is nonlinear function
of factors that cause the seepage forces under the structure. There is, however, no procedure to ascertain the basic barrage
parameters such as depth of sheet piles or cutoffs and the length and thickness of floor in a cost–effective manner. In this
paper, a nonlinear optimization formulation (NLOF), which consists of an objective function of minimizing total cost, is solved
using genetic algorithm (GA). The mathematical model that represents the subsurface flow is embedded in the NLOF. The applicability
of the approach has been illustrated with a typical example of barrage profile. The results obtained in this study shows drastic
cost savings when the proposed NLOF is solved using GA than that of using classical optimization technique and conventional
method. A parametric analysis has also been performed to study the effect of varying soil and hydrological conditions on design
parameters and on over all cost. 相似文献
997.
Naizhuo Zhao Tilottama Ghosh Nathan Allen Currit Christopher D. Elvidge 《Water Resources Management》2011,25(9):2241-2250
Global water resources are vulnerable to depletion due to the increasing demand of an ever-increasing human population. A
country’s water footprint is a measure of the total volume of water needed to produce the goods and services consumed by the
country, including water originating beyond its own borders. The water footprint can be a critical indicator of global water
resource use, but its practical application is hindered by a lack of comparable data across national boundaries. The purpose
of this article is to test the applicability of the nighttime imagery products produced by the Defense Meteorological Satellite
Program’s Operational Linescan System (DMSP-OLS) for the assessment of the global water footprint. To accomplish this purpose,
the average areal extent of nighttime lighting (lit area) is calculated from 1997 to 2001. Next, lit area is regressed on
the total water footprint for each country, as indicated by the Water Footprint Network (WFN), to estimate that country’s
total water footprint using nighttime imagery. Model residuals are analyzed at the national scale to understand the appropriateness
of nighttime imagery for assessing water consumption. Results indicate strong positive correlations between lit area and total
water footprint (TWF), domestic water withdrawal (DWW), and industrial water consumption (IWC) at the national scale. Overall,
the analyses reveal that the rate of agricultural water consumption to total water footprint (AWCR) and population density
can affect the precision of estimates when lit area is selected as a proxy to estimate water footprints. 相似文献
998.
Streamflow Simulation by SWAT Using Different Precipitation Sources in Large Arid Basins with Scarce Raingauges 总被引:2,自引:1,他引:1
Meiyan Yu Xi Chen Lanhai Li Anming Bao Mupenzi Jean de la Paix 《Water Resources Management》2011,25(11):2669-2681
Streamflow from the mountains is the main source of water for the lower plain in arid regions. Accurate simulation of streamflow
is of great importance to the arid ecosystem. However, many large arid drainage basins in northwestern China have low density
of precipitation stations, which makes the streamflow modeling and prediction very difficult. Based on raingauge data and
Tropical Rainfall Measuring Mission (TRMM) data combined with raingauge data, different approaches were explored for spatializing
precipitation in large area with scarce raingauges. Spatialized precipitation was then input into Soil and Water Assessment
Tool (SWAT), a semi-distributed hydrological model, to simulate streamflow. Results from a case study in the Manas river basin
showed that simulated hydrographs using both the approaches are able to reproduce the watershed hydrological behavior. Moreover,
statistical assessment indicated that hydrological model driven by the spatialized precipitation based on radar combined with
raingauge data performed better than that based on gauge data. Radar precipitation estimator can provide a practical data
source for hydrological modeling at a basin scale where the raingauge network is sparse. 相似文献
999.
Gajanan Kisan Khadse Moromi D. Kalita S. N. Pimpalkar Pawan K. Labhasetwar 《Water Resources Management》2011,25(13):3321-3342
To ascertain the quality of drinking water being supplied and maintained, it is necessary to conduct water quality surveillance
for evolving suitable strategy for future planning. In the present investigation, water quality was monitored in treatment
plants, service reservoirs, and at consumer ends in three seasons to assess the baseline water quality status at Shillong
in Meghalaya. There are three water treatment plants at Shillong namely Umkhen, Mawlai and GSWS with design capacities of
1.5, 3.4 and 34 Million liter per day (MLD) respectively. Each treatment plant is having rapid sand filtration followed by
disinfection. The study reveals that the physico-chemical parameters of water quality at consumer end meets Indian drinking
water quality standards (BIS 1991) after conventional treatment followed by disinfection, whereas the bacteriological parameters for raw water sources exceed
the permissible limit indicating the treatment need for drinking purposes. Throughout year the average feacal coliform contamination
at service reservoir and to consumer end were found as 44 to 156 CFU/100 ml which may be attributed to the general management
practices for maintenance of service reservoirs and the possibility of en route contamination. 相似文献
1000.
The effects of bed-load movement on mean flow characteristics were experimentally investigated using particle image velocimetry
(PIV). The gravel beds associated with open-channel flow are hydraulically rough, and two types of grain with different median
diameters were used. The flow field and bed load motion images were simultaneously obtained via the particular experimental
setup. The mass of sediment particles instantaneously moving on the bed, i.e., the sand-wave, was observed in the experiment.
It was found that the sand-waves have an average friction angle of 11.2° and heights ranging from 2.2 d
50 to 3.8 d
50. The mean velocity profiles on the mobile bed can also be represented with logarithmic distribution with deviations occurred
in the near wall region. Based on the Schultz–Grunow formula, a modified equation is developed in this study to better express
the flow resistance factor in terms of the Reynolds number and the ratio of flow depth to roughness height. 相似文献