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Addressing Japan’s disposal of nuclear-contaminated water from the perspective of international human rights law
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作者 Yen-Chiang Chang Xiaonan Zhao 《Chinese Journal of Population,Resources and Environment》 2024年第1期1-9,共9页
The discharge of nuclear-contaminated water containing radionuclides into the ocean by Japan will lead to its integration into the entire ecosystem through processes of circulation and biomagnification,eventually ente... The discharge of nuclear-contaminated water containing radionuclides into the ocean by Japan will lead to its integration into the entire ecosystem through processes of circulation and biomagnification,eventually entering the human body via the food chain.This poses a substantial risk of irreversible damage to both the ecosystem and human health,a situation that will worsen with the ongoing discharge of such water.The respect and protection of human rights represent an international consensus,and safeguarding fundamental human rights is a substantial obligation that states must undertake in accordance with both international and domestic law.Since the Fukushima nuclear disaster,Japan has continuously violated its international legal obligations to protect human rights in several areas,including the resettlement of disaster victims,the reduction of nuclear radiation levels,and the handling of contaminated water.Such actions have compromised and will continue to compromise the basic human rights of not only its citizens but also those of people worldwide,including environmental rights,the right to life,development rights,and food rights.In the aftermath of the Fukushima meltdown,the public and workers involved in handling nuclear contaminants have been continually exposed to high radiation levels,endangering their rights to life,development,and health.Japan’s inadequate efforts in victim resettlement and environmental restoration have jeopardized the environmental and food rights of its citizens to live healthily and access food in an environment unaffected by nuclear radiation.The release of nuclear-contaminated water poses a risk of Japan’s nuclear pollution to the people of neighboring countries and the global population at large.The principle of human rights underpins the theory of a community with a shared future for humanity,and human rights are a crucial area of China’s active participation in United Nations affairs and global governance.By voicing concerns over Japan’s potential human rights violations globally,China demonstrates its role as a responsible major country.In response to Japan’s breach of legal obligations and human rights violations,China can adopt a reasoned and beneficial approach,including calling on the international community to hold Japan criminally accountable for crimes against humanity under the Rome Statute and advancing scholarly discussions on ecocide and crimes against the marine environment.Furthermore,China should persist in seeking advisory opinions from the International Court of Justice and strive for substantive accountability,utilizing the mechanisms of international human rights organizations to make its voice heard. 展开更多
关键词 Fukushima nuclearcontaminated water Crimes against humanity Remedy for violations of human rights right to environment right to life
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Remaining oil distribution characteristics in an oil reservoir with ultra-high water-cut
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作者 Hongmin Yu Youqi Wang +4 位作者 Li Zhang Qingxin Zhang Zhenhai Guo Benzhe Wang Tao Sun 《Energy Geoscience》 EI 2024年第1期219-223,共5页
An accurate mapping and understanding of remaining oil distribution is very important for water control and stabilize oil production of mature oilfields in ultra-high water-cut stage.Currently,the Tuo-21 Fault Block o... An accurate mapping and understanding of remaining oil distribution is very important for water control and stabilize oil production of mature oilfields in ultra-high water-cut stage.Currently,the Tuo-21 Fault Block of the Shengtuo Oilfield has entered the stage of ultra-high water cut(97.2%).Poor adaptability of the well pattern,ineffective water injection cycle and low efficiency of engineering measures(such as workover,re-perforation and utilization of high-capacity pumps)are the significant problems in the ultra-high water-cut reservoir.In order to accurately describe the oil and water flow characteristics,relative permeability curves at high water injection multiple(injected pore volume)and a semiquantitative method is applied to perform fine reservoir simulation of the Sand group 3e7 in the Block.An accurate reservoir model is built and history matching is performed.The distribution characteristics of remaining oil in lateral and vertical directions are quantitatively simulated and analyzed.The results show that the numerical simulation considering relative permeability at high injection multiple can reflect truly the remaining oil distribution characteristics after water flooding in an ultrahigh water-cut stage.The distribution of remaining oil saturation can be mapped more accurately and quantitatively by using the‘four-points and five-types’classification method,providing a basis for potential tapping of various remaining oil types of oil reservoirs in late-stage of development with high water-cut. 展开更多
关键词 Ultra-high water-cut High water injection multiple Four-points and five-types Numerical simulation Remaining oil distribution
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Root distribution and influencing factors of dry-sowing and wet-growing cotton plants under different water conditions
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作者 DING Yu ZHANG Jianghui +4 位作者 BAI Yungang LIU Hongbo ZHENG Ming ZHAO Jinghua XIAO Jun 《排灌机械工程学报》 CSCD 北大核心 2023年第10期1073-1080,共8页
To study the effect of soil water and salt environment factors on the root growth of cotton under different moisture control,three different emergence water volumes(60,105,and 150 m^(3)/hm^(2)),two different frequenci... To study the effect of soil water and salt environment factors on the root growth of cotton under different moisture control,three different emergence water volumes(60,105,and 150 m^(3)/hm^(2)),two different frequencies(high frequency and low frequency)and one double film cover winter irrigation control treatment(CK:2250 m^(3)/hm^(2))were set up to analyze the spatial distribution patterns of soil water and salt environment and root density in dry sown and wet emerged cotton fields under diffe-rent moisture control conditions.The results show that the soil water content and water infiltration range gradually become larger with the increase of seedling water quantity,and the larger the seedling water quantity,the higher the soil water content.With the same seedling water quantity,the soil water content of the high-frequency(HF)treatment becomes obviously larger.The soil conductivity of each treatment tends to decrease gradually with the increase of seedling water and drip frequency,among which the distribution of soil conductivity of S6 treatment is closest to that of CK.With the increase in soil depth,the soil conductivity tends to increase first and then decrease.Compared with the low-frequency(LF)treatment,the high-frequency treatment shows a significantly deeper soil salt accumulation layer.The root length density(RLD)of cotton gradually increases with the amount of seedling water and the frequency of dripping.The soil layer of root distribution gradually deepens with the amount of seedling water in the vertical direction,and the RLD value in the horizontal direction is significantly greater in the mulched area than that in the bare area between films.This research can serve as a solid scientific foundation for the use of dry sowing and wet emergence techniques in cotton fields in southern Xinjiang. 展开更多
关键词 COTTON double film mulching dry sowing and wet germination moisture regulation water and salt distribution root distribution cotton double film mulching dry sowing and wet germination moisture regulation water and salt distribution root distribution
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Effect of droplet characteristics on liquid-phase distribution in spray zone of internal mixing air-mist nozzle
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作者 Wei-li Wu Chang-gui Cheng +2 位作者 Yang Li Shi-fa Wei De-li Chen 《China Foundry》 SCIE EI CAS CSCD 2024年第2期185-196,共12页
In continuous casting production,droplet characteristics are important parameters for evaluating the nozzle atomization quality,and have a significant impact on the secondary cooling effect and the slab quality.In ord... In continuous casting production,droplet characteristics are important parameters for evaluating the nozzle atomization quality,and have a significant impact on the secondary cooling effect and the slab quality.In order to study the behavior of atomized droplets after reaching the slab surface and to optimize the spray cooling effect,the influence of droplet diameter and droplet velocity on the migration behavior of droplets in the secondary cooling zone was analyzed by FLUENT software.Results show that the droplets in the spray zone and on the slab surface are mainly concentrated in the center,thus,the liquid volume fraction in the center is higher than that of either side.As the droplet diameter increases,the region of high liquid volume fraction on the slab surface becomes wider,and the liquid phase distribution in the slab width direction becomes uneven.Although increasing the droplet velocity at the nozzle exit has little effect on droplet diffusion in the spray zone,the distribution becomes more uneven due to more liquid reaches the slab surface per unit time.A prediction formula of the maximum water flow rate on the slab surface for specific droplet characteristics was proposed based on dimensionless analysis and validated by simulated data.A nozzle spacing of 210 mm was recommended under the working conditions in this study,which ensures effective coverage of the spray water over the slab surface and enhances the distribution uniformity of water flow rate in the transverse direction. 展开更多
关键词 continuous casting secondary cooling zone internal mixing air-mist nozzle droplet characteristics liquid phase distribution water flow rate
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Effects on Sucrose Metabolism,Dry Matter Distribution and Fruit Quality of Tomato Under Water Deficit 被引量:20
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作者 QI Hong-yan, LI Tian-lai, ZHANG Jie, WANG Lei and CHEN Yuan-hong(Horticultural College, Shenyang Agricultural University, Shenyang 110161 , P.R.China) 《Agricultural Sciences in China》 CAS CSCD 2003年第11期1253-1258,共6页
Four irrigation treatments were designed with 2,4,6 and 8 d intervals to irrigate, respectively. Watering was stopped when the reading of the moisture tension sensor reached zero. The results indicated that glucose an... Four irrigation treatments were designed with 2,4,6 and 8 d intervals to irrigate, respectively. Watering was stopped when the reading of the moisture tension sensor reached zero. The results indicated that glucose and fructose content of tomato's fruit were increased but sucrose content was decreased with fruit growth and development. In different stages, carbohydrate content of tomato fruit in the treatment 3 was the highest, in the treatment 2 was higher, and in the other treatments was the lowest. SS(sucrose synthase)activity was decreased but SPS(sucrose phosphate synthase)activity was increased with development of tomato. SS and SPS activity were increased but acid invertase and neutral invertase activity of ripe stage were decreased under deficit irrigation. Glucose and fructose content were increased in leaves of tomato under water deficit. Soluble sugars, organic acid and the ratio of sugar/acid in tomato fruits were increased and dry matter accumulation of plant was enhanced under water deficit. But the growth of fruits upside the plant and its dry matter accumulation were badly affected under water stress. 展开更多
关键词 water deficit Tomato(Lycopersicon esculentum Mill.) Sucrose metabolism Dry matter distribution Fruit quality
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Modeling of residual chlorine in water distribution system 被引量:4
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作者 LIXin M.Ukita 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第1期136-144,共9页
Water quality within water distribution system may vary with both location and time. Water quality models are used to predict the spatial and temporal variation of water quality throughout water system. A model of res... Water quality within water distribution system may vary with both location and time. Water quality models are used to predict the spatial and temporal variation of water quality throughout water system. A model of residual chlorine decay in water pipe has been developed, given the consumption of chlorine in reactions with chemicals in bulk water, bio films on pipe wall, in corrosion process, and the mass transport of chlorine from bulk water to pipe wall. Analytical methods of the flow path from water sources to the observed point and the water age of every observed node were proposed. Model is used to predict the decay of residual chlorine in an actual distribution system. Good agreement between calculated and measured values was obtained. 展开更多
关键词 residual chlorine bulk water CORROSION bio film water quality water distribution system flow path water age
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Temporal and spatial distribution characteristics of water resources in Guangdong Province based on a cloud model 被引量:9
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作者 Qi Zhou Wei Wang +2 位作者 Yong Pang Zhi-yong Zhou Hui-ping Luo 《Water Science and Engineering》 EI CAS CSCD 2015年第4期263-272,共10页
With a focus on the difficulty of quantitatively describing the degree of nonuniformity of temporal and spatial distributions of water resources, quantitative research was carried out on the temporal and spatial distr... With a focus on the difficulty of quantitatively describing the degree of nonuniformity of temporal and spatial distributions of water resources, quantitative research was carried out on the temporal and spatial distribution characteristics of water resources in Guangdong Province from 1956 to 2000 based on a cloud model. The spatial variation of the temporal distribution characteristics and the temporal variation of the spatial distribution characteristics were both analyzed. In addition, the relationships between the numerical characteristics of the cloud model of temporal and spatial distributions of water resources and precipitation were also studied. The results show that, using a cloud model, it is possible to intuitively describe the temporal and spatial distribution characteristics of water resources in cloud images. Water resources in Guangdong Province and their temporal and spatial distribution characteristics are differentiated by their geographic locations. Downstream and coastal areas have a larger amount of water resources with greater uniformity and stronger stability in terms of temporal distribution. Regions with more precipitation possess larger amounts of water resources, and years with more precipitation show greater nonuniformity in the spatial distribution of water resources. The correlation between the nonuniformity of the temporal distribution and local precipitation is small, and no correlation is found between the stability of the nonuniformity of the temporal and spatial distributions of water resources and precipitation. The amount of water resources in Guangdong Province shows an increasing trend from 1956 to 2000, the nonuniformity of the spatial distribution of water resources declines, and the stability of the nonuniformity of the spatial distribution of water resources is enhanced. 展开更多
关键词 water resources Temporal and spatial distribution characteristics Cloud model Guangdong Province
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Interactions between wind and water erosion change sediment yield and particle distribution under simulated conditions 被引量:8
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作者 TUO Dengfeng XU Mingxiang +1 位作者 ZHAO Yunge GAO Liqian 《Journal of Arid Land》 SCIE CSCD 2015年第5期590-598,共9页
Wind and water erosion are among the most important causes of soil loss, and understanding their interactions is important for estimating soil quality and environmental impacts in regions where both types of erosion o... Wind and water erosion are among the most important causes of soil loss, and understanding their interactions is important for estimating soil quality and environmental impacts in regions where both types of erosion occur. We used a wind tunnel and simulated rainfall to study sediment yield, particle-size distribution and the fractal dimension of the sediment particles under wind and water erosion. The experiment was conducted with wind ero- sion firstly and water erosion thereafter, under three wind speeds (0, 11 and 14 m/s) and three rainfall intensities (60, 80 and 100 ram/h). The results showed that the sediment yield was positively correlated with wind speed and rain- fall intensity (P〈0.01). Wind erosion exacerbated water erosion and increased sediment yield by 7.25%-38.97% relative to the absence of wind erosion. Wind erosion changed the sediment particle distribution by influencing the micro-topography of the sloping land surface. The clay, silt and sand contents of eroded sediment were also posi- tively correlated with wind speed and rainfall intensity (P〈0.01). Wind erosion increased clay and silt contents by 0.35%-19.60% and 5.80%-21.10%, respectively, and decreased sand content by 2.40%-8.33%, relative to the absence of wind erosion. The effect of wind erosion on sediment particles became weaker with increasing rainfall intensities, which was consistent with the variation in sediment yield. However, particle-size distribution was not closely correlated with sediment yield (P〉0.05). The fractal dimension of the sediment particles was significantly different under different intensities of water erosion (P〈0.05), but no significant difference was found under wind and water erosion. The findings reported in this study implicated that both water and wind erosion should be controlled to reduce their intensifying effects, and the controlling of wind erosion could significantly reduce water erosion in this wind-water erosion crisscross region. 展开更多
关键词 sediment yield particle-size distribution fractal dimension wind and water erosion
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Spatial distribution of soil moisture,salinity and organic matter in Manas River watershed,Xinjiang,China 被引量:9
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作者 Jilili ABUDUWAILI Yang TANG +2 位作者 Mireban ABULIMITI DongWei LIU Long MA 《Journal of Arid Land》 SCIE 2012年第4期441-449,共9页
With the classical statistical and geostatistical methods, the study of the spatial distribution and its in- fluence factors of soil water, salinity and organic matter was carried out for 0-70 cm soil layers in Manas ... With the classical statistical and geostatistical methods, the study of the spatial distribution and its in- fluence factors of soil water, salinity and organic matter was carried out for 0-70 cm soil layers in Manas River watershed. The results showed that the soil moisture data from all soil layers exhibited a normal distribution, with average values of 14.08%-21.55%. Geostatistical analysis revealed that the content of soil moisture had a moder- ate spatial autocorrelation with the ratios of nugget/sill ranging from 0.500 to 0.718, which implies that the spatial pattern of soil moisture is influenced by the combined effects of structural factors and random factors. Remarkable spatial distributions with stripped and mottled features were found for soil moisture in all different soil layers. The landform and crop planting had a relatively big influence on the spatial distribution of soil moisture; total soil salinity was high in east but low in west, and non-salinized soil and lightly salinized soil appeared at the northwest and southwest of the study area. Under the effect of reservoir leakage, the heavily salinized soils are widely distributed in the middle of the study area. The areas of the non-salinized and lightly salinized soils decreased gradually with soil depth increment, which is contrary to the case for saline soils that reached a maximum of 245.67 km2 at the layer of 50-70 cm. The types of soil salinization in Manas River watershed were classified into four classes: the sulfate, chloride-sulfate, sulfate-chloride and chloride. The sulfate salinized soil is most widely distributed in the surface layer. The areas of chloride-sulfate, sulfate-chloride, and chloride salinized soils increased gradually along with the increment of soil depth; the variation range of the average values of soil organic matter content was be- tween 7.48%-11.33%. The ratios of nugget/sill reduced gradually from 0.698 to 0.299 with soil depth increment, which shows that the content of soil organic matter has a moderate spatial autocorrelation. The soil organic matter in all soil layers met normal distribution after logarithmic transformation. The spatial distribution patterns of soil or- ganic matter and soil moisture were similar; the areas with high organic matter contents were mainly distributed in the south of the study area, with the lowest contents in the middle. 展开更多
关键词 soil water and salt organic matter spatial distribution Manas River watershed
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Principal-subordinate hierarchical multi-objective programming model of initial water rights allocation 被引量:5
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作者 Dan WU Feng-ping WU Yan-ping CHEN 《Water Science and Engineering》 EI CAS 2009年第2期105-116,共12页
关键词 initial water rights allocation principal-subordinate hierarchy multi-objective programming model satisfaction degree
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Distribution and fluxes of suspended sediments in the offshore waters of the Changjiang (Yangtze) Estuary 被引量:3
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作者 WAN Xinning LI Jiufa SHEN Huanting 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2009年第4期86-95,共10页
The offshore waters of the Changjiang Estuary are the transitional areas where river-supplied water and sediment are transported to the sea, and material exchanges occur with the neighbored Hangzhou Bay and the Jiangs... The offshore waters of the Changjiang Estuary are the transitional areas where river-supplied water and sediment are transported to the sea, and material exchanges occur with the neighbored Hangzhou Bay and the Jiangsu waters. Field observations of currents and sediment properties were conducted to study temporal and spatial distributions of suspended sediments under various dynamical conditions. The high sediment concentrations were found to occur in the western and southern waters of the offshore, and the low concentrations occurred in the eastern and northern waters. This pattern of the suspended sediment concentration (SSC) distribution is obviously influ- enced by the runoff and tidal current. The significant difference of along-estuary SSC distribution indicates that the SSC is reduced gradually from the west to the east, and that in the spring tide is obviously higher than in the neap tide. The methods of mechanism analysis and equal-area grids were used to calculate the suspended sediment fluxes at the typical cross sections. It was found that 44 percent of total suspended sediments from the Changjiang River were deposited in the submarine delta, and more than 27 percent of sediments were transported southernly into the Hangzhou Bay, and only 9 percent of sediments was supplied and exchanged with the northern Jiangsu waters, and about 20 percent of sediments was delivered offshore to the sea. 展开更多
关键词 Changjiang Estuary offshore waters suspended sediment distribution flux
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Analysis of thermohaline and current distribution characteristics of Zhejiang and Fujian waters in summer 被引量:3
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作者 DU Panjun ZHANG Hui +2 位作者 XIAO Wenjun KANG Xing GUAN Qinle 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2011年第5期71-83,共13页
This paper analyzed the distribution of thermohaline and circulation characteristics of Zhejiang and Fujian waters,based on the cross-sectional thermohaline data and on current data (up to 30 d duration) at fixed-po... This paper analyzed the distribution of thermohaline and circulation characteristics of Zhejiang and Fujian waters,based on the cross-sectional thermohaline data and on current data (up to 30 d duration) at fixed-point moorings,collected in the summer of 2006.We also performed low-pass filtering and spectrum analysis on the mooring submersible buoy data.Based on that analysis,we discussed the characteristics of low frequency currents and time-variations in these waters.The main conclusions are as follows.(1) There is a low salinity pinnate area near the Hangzhou Bay in summer,and outside the low salinity area,an obvious salinity front is present from surface to bottom near 123 E.There is also a temperature front below the surface at a corresponding position.(2) Bottom water of the Taiwan Warm Current comes from the subsurface of Kuroshio.(3) The direction of low frequency current at fixed anchor stations is N-NE or S,which mainly depends on the interaction of control currents in this waters.(4) Significant spectral peaks at all mooring stations are typically semidiurnal and diurnal tides.Semidiurnal tidal waves are the main ones in these waters,and have more energy closer to the shore.(5) Significant energy spectral peaks of middle period (3 to 8 d) of currents are responses to weather frequency.(6) Significant energy spectral peaks of long periods at the surface or bottom are probably responses to seasonal wind or bottom friction,while,the long period peaks of other depths can reflect cyclical changes of interactions between currents.We conclude that the pulsation period of the Taiwan Warm Current in these waters is 10-17 d. 展开更多
关键词 Zhejiang and Fujian waters thermohaline distribution low-frequency current spectrum analysis Taiwan Warm Current Kuroshio subsurface water
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Online location of seismic damage to a water distribution system 被引量:4
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作者 梁建文 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2003年第2期181-187,共7页
As one of the most important urban lifeline systems,a water distribution system can be damaged under a strong earthquake,and the damage cannot easily be located,especially immediately after the event.This often causes... As one of the most important urban lifeline systems,a water distribution system can be damaged under a strong earthquake,and the damage cannot easily be located,especially immediately after the event.This often causes tremendous difficulties to post-earthquake emergency response and recovery activities.This paper proposes a methodology to locate seismic damage to a water distribution system by monitoring water head online at some nodes in the water distribution system.An artificial neural network-based inverse analysis method is developed to estimate the water head variations at all nodes that are not monitored based on the water head variations at the nodes that are monitored.The methodology provides a quick,effective,and practical way to locate seismic damage to a water distribution system. 展开更多
关键词 water distribution system seismic damage BREAK LOCATION extent of damage ONLINE artificial neural network technique
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Particle size distribution and property of bacteria attached to carbon fines in drinking water treatment 被引量:4
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作者 Wang Leilei Chen Wei Lin Tao 《Water Science and Engineering》 EI CAS 2008年第2期102-111,共10页
The quantitative change and size distribution of particles in the effluents from a sand filter and a granular activated carbon (GAC) filter in a drinking water treatment plant were investigated. The average total co... The quantitative change and size distribution of particles in the effluents from a sand filter and a granular activated carbon (GAC) filter in a drinking water treatment plant were investigated. The average total concentration of particles in the sand filter effluent during a filter cycle was 148 particles/mL, 27 of which were larger than 2 μm in size. The concentration in the GAC effluent (561 particles/mL) was significantly greater than that in the sand filter effluent. The concentration of particles larger than 2 μm in the GAC filter effluent reached 201 particles/mL, with the amount of particles with sizes between 2 μm and 15 μm increasing. The most probable number (MPN) of carbon fines reached 43 unit/L after six hours and fines between 0.45 μm and 8.0 μm accounted for more than 50%. The total concentration of outflowing bacteria in the GAC filter effluent, 350 CFU (colony-forming units) /mL, was greater than that in the sand filter effluent, 210 CFU/mL. The desorbed bacteria concentration reached an average of 310 CFU/mg fines. The disinfection efficiency of desorbed bacteria was lower than 40% with 1.5 mg/L of chlorine. The disinfection effect showed that the inactivation rate with 2.0 mg/L of chloramine (90%) was higher than that with chlorine (70%). Experimental results indicated that the high particle concentration in raw water and sedimentation effluent led to high levels of outflowing particles in the sand filter effluent. The activated carbon fines in the effluent accounted for a small proportion of the total particle amount, but the existing bacteria attached to carbon fines may influence the drinking water safety. The disinfection efficiency of desorbed bacteria was lower than that of free bacteria with chlorine, and the disinfection effect on bacteria attached to carbon fines with chloramine was better than that with only chlorine. 展开更多
关键词 drinking water treatment particles size distribution bacteria attached to carbon fines INACTIVATION
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Multi-objective Optimisation Design of Water Distribution Systems:Comparison of Two Evolutionary Algorithms 被引量:3
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作者 Haixing Liu Jing Lu +1 位作者 Ming Zhao Yixing Yuan 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第3期30-38,共9页
In order to compare two advanced multi-objective evolutionary algorithms,a multi-objective water distribution problem is formulated in this paper.The multi-objective optimization has received more attention in the wat... In order to compare two advanced multi-objective evolutionary algorithms,a multi-objective water distribution problem is formulated in this paper.The multi-objective optimization has received more attention in the water distribution system design.On the one hand the cost of water distribution system including capital,operational,and maintenance cost is mostly concerned issue by the utilities all the time;on the other hand improving the performance of water distribution systems is of equivalent importance,which is often conflicting with the previous goal.Many performance metrics of water networks are developed in recent years,including total or maximum pressure deficit,resilience,inequity,probabilistic robustness,and risk measure.In this paper,a new resilience metric based on the energy analysis of water distribution systems is proposed.Two optimization objectives are comprised of capital cost and the new resilience index.A heuristic algorithm,speedconstrained multi-objective particle swarm optimization( SMPSO) extended on the basis of the multi-objective particle swarm algorithm,is introduced to compare with another state-of-the-art heuristic algorithm,NSGA-II.The solutions are evaluated by two metrics,namely spread and hypervolume.To illustrate the capability of SMPSO to efficiently identify good designs,two benchmark problems( two-loop network and Hanoi network) are employed.From several aspects the results demonstrate that SMPSO is a competitive and potential tool to tackle with the optimization problem of complex systems. 展开更多
关键词 water distribution system DESIGN OPTIMIZATION MULTI-OBJECTIVE PARTICLE SWARM OPTIMIZATION
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Leakage Detection in Water Distribution Network Based on a New Heuristic Genetic Algorithm Model 被引量:4
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作者 Ali Nasirian Mahmoud F. Maghrebi Siavash Yazdani 《Journal of Water Resource and Protection》 2013年第3期294-303,共10页
The leakage control is an important task, because it is associated with some problems such as economic loss, safety concerns, and environmental damages. The pervious methods which have already been devised for leakage... The leakage control is an important task, because it is associated with some problems such as economic loss, safety concerns, and environmental damages. The pervious methods which have already been devised for leakage detection are not only expensive and time consuming, but also have a low efficient. As a result, the global leakage detection methods such as leak detection based on simulation and calibration of the network have been considered recently. In this research, leak detection based on calibration in two hypothetical and a laboratorial networks is considered. Additionally a novel optimization method called step-by-step elimination method (SSEM) combining with a genetic algorithm (GA) is introduced to calibration and leakage detection in networks. This method step-by-step detects and eliminates the nodes that provide no contribution in leakage among uncertain parameters of calibration of a network. The proposed method initiates with an ordinary calibration for a studied network, follow by elimination of suspicious nodes among adjusted parameters, then, the network is re-calibrated. Finally the process is repeated until the numbers of unknown demands are equal to the desired numbers or the exact leakage locations and values are determined. These investigations illustrate the capability of this method for detecting the locations and sizes of leakages. 展开更多
关键词 CALIBRATION SSEM water distribution LEAK Detection GENETIC ALGORITHM
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Distribution of organochlorine compounds in water, porewater and sediments in Xiamen Harbour 被引量:2
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作者 张祖麟 洪华生 +2 位作者 陈伟琪 周俊良 徐立 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2000年第3期93-102,共10页
The Concentrations of 18 organochlorine pesticides and 12 polychlorinated biphenyls (PCBs) in water, porewater and sediments from the Xiamen Harbour were analyzed quantitatively. It shows that, the levels of all organ... The Concentrations of 18 organochlorine pesticides and 12 polychlorinated biphenyls (PCBs) in water, porewater and sediments from the Xiamen Harbour were analyzed quantitatively. It shows that, the levels of all organochlorine insecticides varied from 6. 60 to 19 .6 ng/dm3 (in water), 11. 9-78. 5 ng/dm3(in porewater) and not detected (ND) - 0. 58 ng/g dry weight (in sediments), and those of total DDTs were in the range ND - 0. 06 ng/g dry weight. Concentrations of PCBs and in- secticides in porewater were higher than in surface water, due to the higher affinity of these hydrophobic compound for sedimentary phase than to water. It implies there would be a potential flux of pollutants from sediments to overlying water. Compared with the concentrations of these pollutants measured in the Xiamen Harbour in 1993, it is one to several magnitude order lower, which suggests their inputs have been decreased in recent years and possible degradation of these compounds. The levels of these pollutants were also compared with other estuaries. 展开更多
关键词 Organochlorine pesticides polychlorinated biphenyls (PCBs) distribution water POREwater sediment
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Water Distribution and Removal along the Flow Channel in Proton Exchange Membrane Fuel Cells 被引量:2
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作者 丁刚强 TANG Heqing +4 位作者 LUO Zhiping 涂正凯 PEI Houchang LIU Zhichun LIU Wei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2013年第2期243-248,共6页
Distribution expressions of total gas pressure and partial water vapor pressure along the channel direction were established based on lumped model by analyzing pressure loss in the channel and gas diffusion in the lay... Distribution expressions of total gas pressure and partial water vapor pressure along the channel direction were established based on lumped model by analyzing pressure loss in the channel and gas diffusion in the layer. The mechanism of droplet formation in the flow channel was also analyzed. Effects of the relative humidity, working temperature and stoichiometry on liquid water formation were discussed in detail. Moreover, the force equilibrium equation of the droplet in the flow channel was deduced, and the critical flow velocity for the water droplet removal was also addressed. The experimental results show that the threshold position of the liquid droplet is far from the inlet with the increase of temperature, and it decreases with the increase of the inlet total pressure. The critical flow velocity decreases with the increase of the radius and the working pressure. 展开更多
关键词 proton exchange membrane fuel cells pressure loss water distribution water removal
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Seepage field distribution and water inflow laws of tunnels in water-rich regions 被引量:6
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作者 LI Zheng CHEN Zi-quan +2 位作者 HE Chuan MA Chun-chi DUAN Chao-ran 《Journal of Mountain Science》 SCIE CSCD 2022年第2期591-605,共15页
Currently,the water inrush hazards during tunnel construction,the water leakage during tunnel operation,and the accompanying disturbances to the ecological environment have become the main problems that affect the str... Currently,the water inrush hazards during tunnel construction,the water leakage during tunnel operation,and the accompanying disturbances to the ecological environment have become the main problems that affect the structural safety of tunnels in water-rich regions.In this paper,a tunnel seepage model testing system was used to conduct experiments of the grouting circle and primary support with different permeability coefficients.The influences of the supporting structures on the water inflow laws and the distribution of the water pressure in the tunnel were analyzed.With the decrease in the permeability coefficient of the grouting circle or the primary support,the inflow rate of water into the tunnel showed a non-linear decreasing trend.In comparison,the water inflow reduction effect of grouting circle was much better than that of primary support.With the increase of the permeability coefficient of the grouting ring,the water pressure behind the primary lining increases gradually,while the water pressure behind the grouting ring decreases.Thus,the grouting of surrounding rock during the construction of water-rich tunnel can effectively weaken the hydraulic connection,reduce the influence range of seepage,and significantly reduce the decline of groundwater.Meanwhile,the seepage tests at different hydrostatic heads and hydrodynamic heads during tunnel operation period were also conducted.As the hydrostatic head decreased,the water pressure at each characteristic point decreased approximately linearly,and the water inflow rate also had a gradual downward trend.Under the action of hydrodynamic head,the water pressure had an obvious lagging effect,which was not conducive to the stability of the supporting structures,and it could be mitigated by actively regulating the drainage rate.Compared with the hydrostatic head,the hydrodynamic head could change the real-time rate of water inflow to the tunnel and broke the dynamic balance between the water pressure and water inflow rate,thereby affecting the stress state on the supporting structures. 展开更多
关键词 water-rich tunnel Seepage field distribution water inflow law Construction period Operation period
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Occurrence and distribution of vibrios in fishes and shellfishes in coastal waters of Hong Kong 被引量:2
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作者 Xu Huaishu, Li Jun, (College of Marine Life Sciences, Ocean University of Qingdao, Qingdao 266003, China)Phyllis Brayton, Rita R. Colwell, David Swartz, (University of Maryland, College Park, 20742, USA)Norman Y. S. Woo, Zhang Shuting (Department of Biol 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1998年第4期545-553,共9页
The summer occurrence and distribution of vibrios in the fishes and shellfishes in the coasal waters of Hong Kong were investigaed. A total of 69 strains of vibrios were isolated from all samples examined. The strains... The summer occurrence and distribution of vibrios in the fishes and shellfishes in the coasal waters of Hong Kong were investigaed. A total of 69 strains of vibrios were isolated from all samples examined. The strains, along with 10 reference strains were classified with the technique of numerical taxonomy bared on 54 characters and 62 of the 69 strains fell into 5 major phena, identified as V. paraheamolyticus (30 strains), V. alginoloticus (23 strains), V. choloerae (3 strains), V. harveyi (2 strains) and V. fluinalis (4 strains). Among them, V.paraheamolyticus and V. alginolyticus were the predominant species in the fishes, shellfishes and the coastal waters of Hong Kong and comprised 43. 5 % and 33. 3 % of the total Vibrio spp. isolates respectively. Meanwhile, 3 strains of non-Ol V. cholerae were isolated from oyster and it was the first time to record V. cholerae non-Ol in seawater or from shellfishes in Hong Kong. These results highlighted the potential risks of food poisoning associated with raw or undercooked seafood. 展开更多
关键词 VIBRIOS occurrence and distribution SEAFOOD coastal water of Hong Kong
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