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Introduction. In the modern socio-economic and geopolitical development of Russia, the development of industry comes to the fore. Among the many industries, ammonia stations play the most important role. The main regularities of the process of pumping and preparing water. The process consists of six stages, this article discusses the automation of stages 1 and 2: for water treatment and pumping it out with pumps H1 and H2 from the tank P2. Products in the form of purified water are the most important criteria for subsequent production at an ammonia plant, therefore, increased requirements are imposed on the quality of finished products, including the quality of purification of the water used with the help of nanofilters. The required quality cannot be achieved without control the process in an automated mode. Development of a neural network. To control the converters frequency values during the preparation and pumping of water, an artificial neural network must be used. Its development was carried out in the Matlab environment in the Neural Network Toolbox package, input and output data were defined for this, data processing and preparation were performed, as well as the choice of the type and architecture of the neural network. The architecture of the Layer Recurrent neural network, the process of its construction and training in Matlab is described. Testing of neural networks. During testing of the Layer Recurrent network for the degree of their training, the smallest error was obtained for 30 neurons in the hidden layer. The proximity to the set values indicates the applicability of the network for controlling the parameters of frequency converters. Development of the neural network controller model in the Simulink package. The simulation of the control system in the Simulink package using a neural network controller with the Layer Recurrent architecture is performed. Checking the frequencies of the frequency converters H1 and H2 in Simulink for the level parameters in the tanks and in the tank LT1_вх, LT2_вх, LT3_вх showed that the object model works correctly, thus, the simulation of the neural network showed that the training was successful. Conclusion. As a result of the conducted research, an artificial neural network was developed to control the process of preparing and pumping water in the Matlab environment and a simulation of a neural network in the Simulink package.

Carbon materials are widely used in solar-powered seawater desalination (SSD) and have attracted a lot of attention in recent years. Recent developments of carbon-based solar absorbers in SSD are reviewed, including composites of carbon materials with other materials such as metal nanoparticles, semiconductors and biomass materials, their photothermal conversion mechanisms, light utilization efficiencies and salt resistance, and the processes of thermal transport and water transfer. The important roles of carbon in SSD are highlighted, including increasing light absorption, improving photothermal conversion efficiency, and balancing water transfer and salt resistance. The key challenges of carbon-based materials in SSD applications are discussed.

It is a common phenomenon that water transfers in unsaturated coal and iron ore, particularly during experiencing vibrations with low peak acceleration, such as during transport by conveyors or ships. Therefore, understanding the dynamic water transfer during the vibration helps improve the processing and equipment of the materials. This work focused on the basic sinusoidal vibration. The experimental research was conducted from two aspects: different peak accelerations and size groups on coal and iron ore. The effect of the peak acceleration and particle size on water transfer was analysed through analysis of variance (ANOVA). The results demonstrated that the fine particles have obvious different behaviours under vibration comparing with coarse particles and peak acceleration can change the water transferring trend from downward to upward. A fuzzy logic model was also developed to tell the water transferring trend and its predictions were in accordance with the effects found in experiments.

This paper develops a discharge allocation model for public water supply for a set of communities, considering available and planned reservoirs and interbasin transfer projects. Reservoir operation...

Under changing environment, the feasibility and potential impact of an inter-basin water transfer project can be evaluated by employing the coincidence probability of runoff in water sources area (WSA), water receiving area (WRA), and the downstream impacted area (DIA). Using the Han River to Wei River Water Transfer Project (HWWTP) in China as an example, this paper computed the coincidence probability and conditional probability of runoff in WSA, WRA and DIA with the copula-based multivariate joint distribution and quantified their acceptable and unfavorable encounter probabilities for evaluating the water supply risk of the water transfer project and exploring its potential impact on DIA. Results demonstrated that the most adverse encounter probability (dry–dry–dry) was 26.09%, illustrating that this adverse situation could appear about every 4 years. The acceptable and unfavorable probabilities in all encounters were 44.83 and 55.17%, respectively, that is the unfavorable situation would be dominant, implying flood and drought risk management should be paid greater attention in project operation. The conditional coincidence probability (dry WRA & dry DIA if dry WSA) was close to 70%, indicating a requirement for an emergency plan and management to deal with potential drought risk. HIGHLIGHTS Coincidence probability of annual runoff in all main impacted areas is investigated.; Copula-based method to capture the encounter situations of water transfer project.; Acceptable and unfavorable probabilities in all encounters imply water transfer risk.; Conditional coincidence probability with dry water resources area was computed.; An emergency water scheduling plan is required to deal with potential drought risk.

In South Korea, rainfall deficits lasting for three years (2014–2017), have decreased the reservoir storage level. The Boryeong reservoir, located in the Geum River western sea basin, recorded the lowest reservoir storage. The Boryeong water transfer project has supplied water resources to the east side of the basin. This is an emergency water supply project operated when there is a water supply shortage in the reservoir. It is essential to use appropriate settings for the operation scheme. In this study, a reservoir simulation model was built by applying a water supply adjustment standard, which reduces the water supply when reservoir storage is decreased to a specific level. Four operation cases (no operation, continuous operation, and two temporary operations) were used to analyze the effects of the project. The temporary operations activate when the reservoir storage decreases. The volumetric reliability of the water supply is enhanced by 1.8–2.2% in the temporary operation cases. This study used cost-benefit analysis to analyze the two temporary operation cases. Operating the transfer project when reservoir storage goes below a certain level is more efficient than other cases.

Liquid transport in textile fabrics determines thermal comfort during high physical activity of a person when liquid perspiration is produced and needs to be transferred away from the skin to keep the thermal balance. In this investigation, an attempt was made to get some indications of how the combination of the fabric composition, geometry and dimensional stability, and the moisture content influences liquid transfer properties of plain weft knitted fabrics. Therefore, the knitted fabrics made from pure hydrophilic (hemp fibres), pure hydrophobic (acrylic fibres) and a hydrophilic/hydrophobic (hemp/acrylic) fibre blend underwent a trial wear and care period. The Malden Mills water distribution test was performed for the knitted fabrics with different moisture contents (0-30 %) in order to evaluate the effect on liquid transfer properties. Water transfer ability and water holding capacity of the knitted fabrics were also determined after undergoing the wear trial test. The obtained results were analysed with respect to macro and micro scales of porosity of knitted fabrics. It has been shown that the geometric configuration of the complex porous network in knitted fabrics influenced their liquid transfer properties in the whole moisture content range regardless of the composition. Despite the reconfiguration of the pore system in the knits during the trial period, their liquid transfer properties were still dependent on the pore size and distribution. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 171029]

Inter-basin water diversion reallocates water resources by changing their spatio-temporal distribution characteristics between basins. This can effectively relieve water supply and demand conflicts in regions with water resource reserves shortages. However, building inter-basin water diversion projects obviously reduces the inflow from upstream, leading to increasingly conspicuous conflicts between water diversion outside a basin and water utilization inside the basin. To relieve this conflict and explore the optimal scheme of water resource allocation across river basins, this paper chooses the Middle Route Project of the South-to-North Water Diversion Project on the Hanjiang River as a case study. A water supply scheduling model of Danjiangkou Reservoir is built using an integrated inter-basin diversion draw water reservoir regulation (IDR) model to balance multiple conflicting water demands. In the IDR model there are two types of objective sets: aggregate indicators and process matching degree functions. Moreover, six evaluation indexes are selected to analyze the water resource allocation effect of the optimal scheme. The simulation results indicate that the proposed IDR model in this paper is practicable and efficient for water resource allocation across river basins.

Interbasin water transfer (IBWT) projects are of great practical significance for alleviating water shortages due to the nonuniform spatiotemporal distribution of water resources. An approp...

We proposed a passive water transfer/retention system for a device such as a sensor electrode for long-term functionality. This design aims to provide water to a device/material in order to keep the device/material in a wet condition for a long time using a small amount of water in the reservoir. Our design does not need any active sensor, pump, or valve to control the water refilling. This design can be used for the application such as on-site monitoring of the soil nutrients.

The Gulf Cooperation Council (GCC) countries lack renewable freshwater resources, yet demand for water is rising fast. The groundwater as the largest freshwater supplier has significantly dwindled ...

Highly-efficient solar steam generator holds promise in seawater desalination and wastewater treatment with low energy consumption. The efficiency of generator highly depends on several factors including the kind of the absorber layer, the structure and the thickness of the generators. In this study, a model for calculating the optimal thickness was established based on the water transfer rate and thermal conduction loss. An optimal thickness of generator was determined by the calculation and experiment, taking carbonized wood based solar steam generator (CWSG) as an example. CWSG with optimal thickness about 22 mm performed a highest evaporation rate of 6.89 kg m−2 h−1, corresponding to efficiency of 87.7% under 5 sun. CWSG also served for seawater desalination and dye removal, which exhibited a stable performance even after 20 cycles. The results indicate that maximizing the efficiency of solar steam generator by thermal calculation could provide a new choice to design highly efficient solar steam generator for seawater desalination and dye removal.

The utilization of floodwater resources will produce benefits, but it will also pose risks; therefore, it is necessary to strengthen knowledge regarding risk assessment to minimize negative effects. In the present study, the risk factors for the utilization of floodwater resources in water diversion projects were identified, the index system was constructed, and the fuzziness and randomness of the risk were considered. Assessment was performed with respect to the following three projects: water storage, water conveyance, and water pumping. The specific methods to improve the cloud model are as follows: analytic hierarchy process (AHP) is used to calculate subjective weights, entropy weight method and projection pursuit method are used to calculate objective weights, X-conditional cloud is used to calculate index membership degree, and finally combination weight and membership degree are combined to obtain the risk level of flood resource utilization. The above methodology was applied to the risk assessment of floodwater resources utilization in the Jiangsu Province of the East Route of the South-to-North Water Transfer Project. The risk of floodwater resources utilization in high-flow, normal-flow, and low-flow years was evaluated, and the validity and applicability of the assessment method were verified.

Preparation of high-quality films plays an important role to achieve high-performance nonfullerene (NF) organic solar cells. NF active layer films are typically fabricated by spin coating. Novel fabrication methods to process the NF active layer are desirable to be compatible with large-area production. Herein, we report on the fabrication of NF active layer films via a water transfer printing method. This method delivers a uniform film with controllable film thicknesses. NF active layers of PDBD-T:ITIC and PBDB-T-2F:IT-4F were fabricated via the method to validate its effectiveness. Solar cells with the water transfer-printed active layers show comparable performance (up to 11.7%) to the cells with spin-coated active layers. Furthermore, NF solar modules containing 4-sub cells with the active area of 3.2 cm2 are also fabricated via the method. The module shows VOC of up to 3.4 V and a power conversion efficiency of 8.1% with the PBDB-T-2F:IT-4F active layer.

Reservoir operation plays an important role in the coevolution of the nexus across water supply, power generation, and environment (WPE) systems. This paper aims to contribute to the state-of-the-art in how multi-objective reservoir operation can be modeled within the framework of the WPE nexus by incorporating the interactions among reservoirs operation, stakeholders’ decision preferences, and WPE systems. Specifically, five ordinary differential equations are used to describe the dynamics of WPE states. These dynamics are driven by a multi-objective optimization model that optimizes reservoir operation decisions. Two novel response linkages that describe how the reservoir operational decisions influence socio-economic variables and how the environmental awareness influences stakeholders’ preference for reservoir operation are proposed in this study. The Middle Route of China’s South-to-North Water Transfer Project is selected as the case study. The results show that: (1) response linkages are effective in describing the interactions between reservoir operational decisions and WPE systems, (2) tradeoffs across WPE systems and reservoir operational decisions shift from stage to stage because of the changing socio-economic conditions, and (3) the control parameter that dominates the shift in stable levels of a given variable can be identified. These results highlight the importance of re-evaluating involved tradeoff effects and updating of operational policies periodically, and how our modeling approach can be used to detect and guide such adaptions.

Water transfer projects in China have become a popular research topic in recent years. This study develops a method for evaluating the comprehensive impacts of water transfer projects on regional development. In the qualitative assessment, the comprehensive index method is employed, and an evaluation index system is established from economic, social and environmental perspectives. In this approach, the weights are determined by the analytic hierarchy process (AHP) and the entropy combined method. In the quantitative assessment, the sharing coefficient method is used. The procedure is applied to the water transfer project from the Yangtze River to the Taihu Lake. The qualitative results indicate that the conclusion of the water transfer project had a ‘large positive impact’ in 2016. In the quantitative assessment, the comprehensive benefit of increasing water supply via the project was 1.87 billion CNY in 2016. In addition, the integrated impact assessment method can be implemented at the seasonal scale to produce refined results. These results show that the proposed method can provide technical support for project operation and policy formulation.

The new information, that has become available at present, makes it possible to outline a mechanism of brain water metabolism in the realization of which an important role belongs to AQP4, the main aquaporin of the brain. This aquaporin controls water transfer across the blood-brain barrier and water exchange between brain parenchyma and the cerebrospinal fluid. In the world literature, AQP4 is viewed as a molecular target for the drug action directed at correction of the brain water metabolism disorders in pathologies. The new knowledge made it possible to outline principal approaches to pharmacological correction of cerebral water metabolism disorders and edema.

Devising a cost effective way to fabricate sensors onto non-planar surfaces is of particular interest in many industrial applications such as condition monitoring or process controlling. This paper presents a low cost and low tech alternative approach for the fabrication of sensors on non-planar substrates in a two-step process. Screen printing is used to create a 2D pattern of the sensor on a water transfer foil which, in a second step, is transferred on a non-planar substrate using water transfer printing. We demonstrate the feasibility of this water transfer technique by fabricating a strain as well as a temperature sensor, which are both characterized and compared with state of the art screen printed sensors on planar substrates.

This study evaluated the impact of unilateral cleft lip nasal deformity (uCLND) on the ability of the nasal passages to warm and humidify inspired environmental air using computational fluid dynamics (CFD) modeling. Nasal air conditioning was simulated at resting inspiration in ten individuals with uCLND and seven individuals with normal anatomy. The overall heat and water transfer through nasal mucosa was significantly greater (p = 0.02 for both heat and moisture fluxes) on the non-cleft side than on the cleft side. Unilateral median and interquartile range (IQR) for heat flux (W/m2) was 190.3 (IQR 59.9) on the non-cleft side, 160.9 (IQR 105.0) on the cleft side, and 170.7 (IQR 87.8) for normal subjects. For moisture flux (mg/(s·m2), they were 357.4 (IQR 112.9), 298.7 (IQR 200.3) and 320.8 (IQR 173.0), respectively. Significant differences of SAHF50 between cleft side of uCLND and normal existed except for anterior region. Nevertheless, air conditioning ability in subjects with uCLND was generally comparable to that of normal subjects.

In practice, face masks tend to be a group of daily supplies for people’s life. The microenvironment between mouth and face masks was complicated, where the excess moisture increased the unconformable feeling. The moisture harvesting was associated with the surface chemistry of the substrate, the thermal equilibrium among the drop, substrate, and environment, and the structure of the substrate. The process of the successful moisture harvesting system included dropwise condensation and water transfer. Although there were few studies related to the niche topic, the review was aimed to inspire the design of the practical face masks from the other basic studies.

In order to meet the demand of emergency water supply in the northern region without affecting normal water transfer, considering the use of the existing South-to-North Water Transfer eastern route project to explore the potential of floodwater resource utilization in the flood season of Hongze Lake and Luoma Lake in Jiangsu Province, this paper carried out relevant optimal operating research. First, the hydraulic linkages between the lakes were generalized, then the water resources allocation mode and the scale of existing projects were clarified. After that, the actual available amount of flood resources in the lakes was evaluated. The average annual available floodwater resources in 2003–2017 was 1.49 billion m3, and the maximum available capacity was 30.84 billion m3. Then, using the floodwater resource utilization method of multi period flood limited water levels, the research period was divided into the main flood season (15 July to 15 August) and the later flood season (16 August to 10 September, 11 September to 30 September) by the Systematic Clustering Analysis method. After the flood control calculation, the limited water level of Hongze Lake in the later flood season can be raised from 12.5 m to 13.0 m, and the capacity of reservoir storage can increase to 696 million m3. The limited water level of Luoma Lake can be raised from 22.5 m to 23.0 m (16 August to 10 September), 23.5 m (11 September to 30 September), and the capacity of reservoir storage can increase from 150 to 300 million m3. Finally, establishing the floodwater resource optimization model of the lake group with the goals of maximizing the floodwater transfer amount and minimizing the flood control risk rate, the optimal water allocation scheme is obtained through the optimization algorithm.

The population of Istanbul increased from three to fifteen million from 1970 to 2018. The city, which has no perennial fresh water resources within its metropolitan boundaries, has long imported water from other basins. In this study, the performance of a reservoir system fed by surface runoff and inter-basin water transfer is investigated and applied. Simulations are run for water demand estimates and with Gamma-distributed realizations of monthly precipitation, based on 105-year temperature and precipitation data. The research shows that after 2060, existing and transferred water alone will not be sufficient to meet demand and it is expected that the megacity Istanbul will be on a path towards water crisis after this date, if not before. It is concluded that it is vital to adopt a more diversified water supply and demand management portfolio with extensive Integrated Water Resources Management (IWRM) measures for “Water Sensitive Cities”. Strategies for reliable system operation that take foreseeable environmental problems into account are proposed.

Good management of water resources requires a good allocation of their availability, especially in public irrigated schemes in Tunisia. This paper contributes to a better reallocation of available water resources at the farm and regional levels. A case study was discussed in the Kalâa Kebira region, in the center-east of Tunisia. Regional models based on aggregation and the possibility of water transfer between two irrigated schemes was tested. The results show that a good seasonal allocation is possible with a total regional exchange of 9.60% m3 of water available between these two schemes. This reallocation is beneficial at the regional level, recording an increase of 2.12% in agricultural income and less beneficial, except for farms that are less competitive, in terms of use of water resources. This reallocation also allows for cultural diversity and specification of agricultural farms. Competitiveness in the water use, diversification and specification of agricultural production systems help to preserve natural resources but they also help to satisfy demand of the regional market.Good management of water resources requires a good allocation of their availability, especially in public irrigated schemes in Tunisia. This paper contributes to a better reallocation of available water resources at the farm and regional levels. A case study was discussed in the Kalâa Kebira region, in the center-east of Tunisia. Regional models based on aggregation and the possibility of water transfer between two irrigated schemes was tested. The results show that a good seasonal allocation is possible with a total regional exchange of 9.60% m3 of water available between these two schemes. This reallocation is beneficial at the regional level, recording an increase of 2.12% in agricultural income and less beneficial, except for farms that are less competitive, in terms of use of water resources. This reallocation also allows for cultural diversity and specification of agricultural farms. Competitiveness in the water use, diversification and specification of agricultural production systems help to preserve natural resources but they also help to satisfy demand of the regional market.

In water-deficient rivers, environmental flows (e-flows) are usually sustained via inter-basin water transfer projects from water-sufficient rivers, but these projects incur tremendous costs and may lead to many negative ecological effects, such as ecological invasion. This research proposed to transfer hydropower instead of water from water-sufficient rivers, because hydropower could substitute for water to promote economic development and reduce water withdrawal from water-deficient rivers. In this research, we established a computable general equilibrium model to analyze the substitution of hydropower for water in a water-deficient river basin, and determined the water withdrawal volume that could be reduced (conserved water). In addition, we adopted a range-of-variability approach to measure the effectiveness of e-flow provisions, and optimized the use of the conserved water to better maintain e-flows. The Luanhe River was adopted as a study case. The results showed that: the water-hydropower equivalent decreased as the transferred hydropower into the Luanhe River basin increased; a transferred hydropower amount of 22.46 kWh/s, equivalent to 18.30 m3/s conserved water, was optimal for the river basin; the conserved water should be distributed to the Luanhe River in the proportions of 0.55:0.1:0.35 during the wet, normal and dry seasons, respectively; the policy could transform the macro-economy toward a lower air-pollution pattern.

Studies have shown that the performance of multi-objective evolutionary algorithms depends to a large extent on the shape of the Pareto fronts of the problem. Although, most existing algorithms have poor applicability in dealing with this problem, especially in the multi-objective optimization operation of reservoirs with unknown Pareto fronts. Therefore, this paper introduces an evolutionary algorithm with strong versatility and robustness named the Multi-Objective Evolutionary Algorithm with Reference Point Adaptation (AR-MOEA). In this paper, we take two water conservancy hubs (Huangjinxia and Sanhekou) of the Hanjiang to Wei River Water Diversion Project as example, and build a multi-objective operation model including water supply, ecology, and power generation. We use the AR-MOEA, the Non-dominated Sorting Genetic Algorithm II (NSGA-II), the Multi-Objective Evolutionary Algorithm based on Decomposition (MOEA/D) and the Indicator-Based Evolutionary Algorithm (IBEA) to search the optimal solutions, respectively. We analyze the performance of four algorithms and the operation rules in continuous dry years. The results indicate that (1) the AR-MOEA can overcome the difficulty of the shape and distribution of the unknown Pareto fronts in the multi-objective model. (2) AR-MOEA can improve the convergence and uniformity of the Pareto solution. (3) If we make full use of the regulation ability of the Sanhekou reservoir in the dry season, the water supply for coping with possible continuous dry years can be guaranteed. The study results contribute to the identification of the relationship among objectives, and is valued for water resources management of the Hanjiang to Wei River Water Diversion Project.

Although water transfer projects can alleviate the water crisis, they may cause potential risks to water quality safety in receiving areas. The Miyun Reservoir in northern China, one of the receiving reservoirs of the world’s largest water transfer project (South-to-North Water Transfer Project, SNWTP), was selected as a case study. Considering its potential eutrophication trend, two machine learning models, i.e., the support vector machine (SVM) model and the random forest (RF) model, were built to investigate the trophic state by predicting the variations of chlorophyll-a (Chl-a) concentrations, the typical reflection of eutrophication, in the reservoir after the implementation of SNWTP. The results showed that compared with the SVM model, the RF model had higher prediction accuracy and more robust prediction ability with abnormal data, and was thus more suitable for predicting Chl-a concentration variations in the receiving reservoir. Additionally, short-term water transfer would not cause significant variations of Chl-a concentrations. After the project implementation, the impact of transferred water on the water quality of the receiving reservoir would have gradually increased. After a 10-year implementation, transferred water would cause a significant decline in the receiving reservoir’s water quality, and Chl-a concentrations would increase, especially from July to August. This led to a potential risk of trophic state change in the Miyun Reservoir and required further attention from managers. This study can provide prediction techniques and advice on water quality security management associated with eutrophication risks resulting from water transfer projects.

Classifying the influencing factor of benefit evaluation of water transfer project based on cost analysis and benefit analysis. The benefit evaluation index system of east line of South-to-North water transfer project is established, including six aspects of Economic cost, Social cost, Environmental cost, Economic benefit, Social benefit, Ecological benefit, totaling 16 indexes. At the same time, the standards of each index corresponding to different grades are determined. In view of the single result in the process of benefit evaluation, ignoring the randomness and fuzziness of index data, a comprehensive evaluation method based on combination weight and trapezoid cloud model is adopted. In this method, the weight obtained by combination of G1 and improved CRITIC weight method is combined with the index certainty obtained by trapezoid cloud model to realize the comprehensive evaluation of project benefits. Finally, taking Jiangsu section of phase I of east line of South-to-North water transfer project as an example, the effectiveness and applicability of the proposed benefit evaluation system and method are verified by analyzing and comparing the evaluation results.

In this study, a practical approach to evaluate the sustainability of river basins subjected to an inter-basin water transfer project is developed. Selection of appropriate evaluation indicators is pivotal to such approach. To make use of huge amount of data, composite indicators of sustainability (CIS) should be utilised. The proposed approach relies on 15 sustainability indicators (SI) that cover three major criteria namely (economic, social and environmental), and aggregates them into eight different types of sustainability indices for a more robust outcome. Two scenarios were considered within the source and recipient basins. Furthermore, multivariate principal component analysis (PCA) was applied to determine principal and non-principal indicators for the two river basins. The ability of CIS and PCA methods were verified via correlation and simple regression methods respectively. The results demonstrated that inter-basin water transfer may improve sustainability, provided that a proper water resource management is enforced.

Cross-border drinking water supply is often a solution for the emerging water crisis, related also to climate changes, but in several cases also a historical legacy of changing borders. It is challenged by the increased complexity of water supply management, mainly because of the doubled reality of administrative, legal, accounting and decision-making processes. Analyzed water pricing of existing cross-border utilities clearly demonstrates applied water pricing approaches mainly based on pure negotiation principles demonstrating different and often heavily asymmetric bargaining positions of partners. In order to overcome this situation applicable water pricing principles are presented. The model is demonstrated on real business cases of three water utilities from Central and South East Europe, but similar concepts are applicable for drinking water transfer between regions or municipalities in other countries.

Operating strategies for inter-basin water transfer-supply reservoirs play an important role in assisting in the decision-making process of effectively transferring and supplying water. This article presents a bi-level optimization model for determining operating strategies for inter-basin water transfer-supply reservoirs. The bi-level model avoids the structural description limitation of traditional optimization models, which normally optimize all of the variables simultaneously, by exactly describing the leader-follower framework used in water transfer-supply. The bi-level optimization problem was solved by using Adaptive Genetic Algorithm (AGA) and was compared with the traditional optimization model. Furthermore, to improve the solution procedure, two methods were used to improve the initial solution of the bi-level model, both based on probability description methods and chaos optimization. The method was applied in a case study of Biliu River reservoir, which is located in Liaoning Province, Northeast China. The results demonstrated that the bi-level model mathematically represents the hierarchical structure of inter-basin water transfer-supply operating strategies, but it requires more time than traditional models to find optimal solutions. Thus, this article proposes methods to improve the solution procedure. The results showed that the proposed bi-level model with the improved solution procedures achieves better reservoir operation performance and shorter calculation times than the general solution procedure when the same decision variables are considered. The amounts of transferred water and abandoned water decreased by 3.8% ~ 9.3% and 5.4% ~ 12.1%, respectively, thus representing an improvement in the efficiency of water transfer. Moreover, the calculation time was decreased by approximately 60%, relative to that of the general solution procedure.

Inter-basin water transfer projects are usually considered as one of the most effective facilities to balance the non-uniform temporal and spatial distribution of water resources and water demands by diverting water from surplus to deficient area. However, the operation of these projects are always daunting, especially for projects with multi-donor reservoirs but only one recipient reservoir. In this study, a set of water transfer rule curves are firstly proposed to determine when, where and how much water should be diverted from each donor reservoir. In addition, a simulation-optimization model with the objective to minimize both water shortage risk and vulnerability is established to derive the optimal operation rule curves. Following that, the new transfer rules are applied to provide guidelines for the operation of a water transfer-supply project with two donor reservoirs in central China. The effects of water diversion on each reservoir are evaluated under different scenarios including no diversion, diversion from the donor reservoir with relatively sufficient water, diversion from the donor reservoir with relatively limited water, and diversion from both donor reservoirs. The results show the advantages of improving the performance of whole water diversion system and demonstrate the feasibility of the proposed approach.

The North China Plain is the scarcest water region in China. Its water security is closely related to interregional water movement, which can be realized by real water transfers and/or virtual water transfers. This study investigates the roles of virtual water trade and real water transfer using the Interregional Input-Output model. The results show that the region is receiving 19.4 billion m3/year of virtual water from the interregional trade, while exporting 16.4 billion m3/year of virtual water in the international trade. In balance, the region has a net virtual water gain of 3 billion m3/year from the outside. Its virtual water inflow is dominated by agricultural products from other provinces, totalling 16.6 billion m3/year, while its virtual water export is dominated by manufacturing sectors to other countries, totalling 11.7 billion m3/year. Both virtual water imports and real water transfers from the South to North Water Diversion Project are important water supplements for the region. The results ...

The objective of this paper is twofold: first, to introduce an innovative technique for extracting and exploiting the Electromagnetic (EM) waveguide dispersion of civil engineering materials by means of GPR; and second, to monitor the water ingress front during the absorption process for various concrete mixes. This technique is based on a new inversion procedure that applies the Electromagnetic Waveguide Model (WGM) to invert phase velocity dispersion curves in their modal form. A Parallel homogenization model, derived from the Lichtenecker-Rother equation, has been employed to extend the waveguide from a one-layer to a two-layer medium. The WGM outputs are then used to estimate the geometric parameters of the propagation medium and offer a primary application to water transfer monitoring in concrete through capillarity effects. The initial WGM validation is carried out on FDTD-simulated propagation signals, while the second validation relies on GPR data acquired from homogeneous materials. To achieve the second objective, a broad-based experimental study is conducted for the purpose of correlating electromagnetic waveguide dispersion parameters with both the geometric and hydric characteristics of various concrete mixes. Results obtained using the two-layer WGM serve to monitor the water ingress front during an absorption process. These results are then compared to the moisture gradients generated on cores using gammadensimetry, which is set as the reference. This procedure yields a number of trends, which in turn provide key information on the conditioning state of the studied concretes.

Contact ultrasound reinforced heat pump drying (CUHPD) experiments of kiwifruit slices were performed to investigate the effect of ultrasound application on drying process, microstructure, and several nutrient components of kiwifruit slices. The results showed that the CUHPD of kiwifruit slices was an internal diffusion‐controlled process, in which ultrasound application could improve the dehydration rate significantly, and higher ultrasonic power led to shorter drying time. Scanning electric microscopy results illustrated that the ultrasound treatment could produce more micropores and larger microchannels inside kiwifruit slices, and thus reduce the hardness and brittleness values. Both ultrasonic power and drying temperature could significantly affect the total phenolic content, VC content, and total sugar content. Contact ultrasound application in the heat pump drying (HPD) process was conducive to improve the nutrient contents at all drying temperatures. Hence, contact ultrasound application is a promising way to effectively promote the dehydration rate and to improve the product quality of HPD on kiwifruit slices. Practical applications Heat pump drying (HPD) is one of the modern drying methods and has some excellent advantages such as energy‐saving and easy operation. However, it has a certain disadvantage like long drying time for those agricultural materials with great internal mass transfer resistance. In this study, the contact ultrasound reinforcing technology was applied to accelerate internal water transfer and improve the drying rate of HPD on kiwifruits. The results showed that the contact ultrasound application could produce a significant reinforcing effect on internal moisture diffusion and dehydration rate, and then reduce the drying time. The increase in ultrasonic power was conducive to improve dried kiwifruit's quality and protect nutrient components in kiwifruit slices compared with single HPD. Therefore, CUHPD is a promising drying method for kiwifruits and can even be effectively applied for other agricultural product drying.

Cascade pumping stations (CPSs) in open-channel water transfer systems usually consume vast amounts of energy and are expensive to operate. For these CPS systems, scheduling optimization is...

Water transfer engineering is an essential approach for lake restoration. It has been widely used for water supply and energy production around the world. Besides, it has been successfully applied in several water bodies for different purposes, namely, for accelerating water exchange, diluting polluted water, improving water quality, and mitigating eutrophication issues.

The optimal operation of an interbasin water transfer multireservoir system (IWTMS) is more complicated than a general one-basin multireservoir system because water release and water transfer occur simultaneously. Previous studies primarily employed reservoir zoning and rule curves to deal with the relationship between reservoir water release and water transfer, and the operating priorities for water release and water transfer are established by decision-makers. However, these priorities may be somewhat subjective and result in suboptimal operation of the entire system. To overcome this shortcoming, a genetic algorithm (GA)-based optimization model was developed to endeavor to get the optimal operation of an IWTMS. The optimization model consists of a GA and a simulation process based on water balance equation, and was applied to a typical IWTMS in Rizhao City, Shandong Province, China. The results showed that the GA was effective and efficient on solving the optimization problem of IWTMSs, and the reliability of the system’s water supply increased from 70.6 to 88.4% due to water transfer and could increase further to 96.4% by implementing optimization.

Since the electricity is not generated and consumed in the same region, the requirements of electricity transmission are increasing which drive inter-provincial virtual water transmission in China. The spatial distribution imbalance of water resources and large volumes of energy resources might aggravate the water scarcity in water shortage regions. It is vital to have a better understanding of the interprovincial virtual water flows coupled with electricity flows, which could provide insights into water resource reallocation through electricity system. Here, we combined interprovincial electricity transmission data with water intensity of different electricity types to analyze the interprovincial electricity-related water transfer during the period of 2005 and 2014. According to the electricity mix of each province and water intensity of each generation type, the synthetical water intensity was obtained. Eventually, inter-provincial virtual water trade model was built by combining provincial synthetical water intensity with electricity flow data, the inter-provincial virtual water transmission matrix from 2005 to 2014 was analyzed to investigate the evolvement of virtual water network related to electricity transmission. The main results showed that the number of provincial water transfers have increased from 449.75Mm3 to 2559.71Mm3 for ten years. Besides, water transfers in several provinces are improving rapidly, and that of most provinces keep steady. By optimizing the deployment transmission of electricity to reallocate water resources of provinces might be a new perspective to stave off water scarcity in China.

To nationally optimize limited water resources, the Chinese government has had to build several nationwide long-distance water transfer channels. These channels have placed tremendous pressure on land resources, and some require large quantities of electrical energy to lift the water to a higher altitude. Within this context, this study attempts to make full use of local solar energy resource and upper space of water channel to construct an on-channel photovoltaic (PV) system. Based on-site data and PVsyst model, this study took the central line of the “South-to-North water diversion” project as an example to examine the technical and economic feasibility of the proposed on-channel PV system under two alternative scenarios. The major results indicated that the initial investment would be 3,733 million Yuan under the scenario 1, with an expected annual electricity output of 659 GWh; while under the scenario 2, the number of initial investments would increase to 18.665 billion Yuan with an expected electricity output of 3.295 billion kWh. Moreover, carbon balance analysis demonstrated that the rate of carbon emission reduction can reach as much as 98.45% comparing to the baseline case. Overall, the proposed on-channel PV system will bring good benefits both economically and environmentally and should be worthy of promoting in future.

In the emergency management relevant to chemical contingency spills, efficiency emergency rescue can be deeply influenced by a reasonable assignment of the available emergency materials to the related risk sources. In this study, an emergency material scheduling model (EMSM) with time-effective and cost-effective objectives is developed to coordinate both allocation and scheduling of the emergency materials. Meanwhile, an improved genetic algorithm (IGA) which includes a revision operation for EMSM is proposed to identify the emergency material scheduling schemes. Then, scenario analysis is used to evaluate optimal emergency rescue scheme under different emergency pollution conditions associated with different threat degrees based on analytic hierarchy process (AHP) method. The whole framework is then applied to a computational experiment based on south-to-north water transfer project in China. The results demonstrate that the developed method not only could guarantee the implementation of the emergency rescue to satisfy the requirements of chemical contingency spills but also help decision makers identify appropriate emergency material scheduling schemes in a balance between time-effective and cost-effective objectives.

Milk is extremely perishable, and yet it has to be preserved for later consumption. In this view, membrane filtration, vacuum concentration lactose crystallization, homogenization and spray drying dehydration are valuable techniques to stabilize most dairy ingredients. Considering the increasing development of dairy trade, there is a need for the dairy industry to improve its understanding of how these concentration and spray drying processes affect the quality of the resulting dairy powders, so to control it. However, the residence time of the droplet and the powder in the spray dryer is so short that it is very difficult to implement studies on the mechanisms of the structural changes in the protein without fundamental research into the process/product interactions. Moreover, several authors have reported the crucial and specific role of dairy components in the mechanisms of water transfer during drying and rehydration. The aim of this paper is to review the present and recent advances in knowledge and innovations, on the properties of spray-dried dairy products, on the modelling and simulation of water transfer processes (drying and rehydration) and on spray drying equipment and energy consumption.

The optimisation of water pumping plant activation schedules is a significant issue when managing emergency and costly water transfer under a drought risk. This problem needs specific optimisation tools to deal with complex multi-reservoir supply systems and to consider different alternative scenarios. The effectiveness of emergency transfers alleviating droughts requires early warning and activation; on the other hand, the high operating costs of pump stations require system managers to take a robust approach that defines activation rules. The proposed optimisation procedure combines scenario optimisation analysis with a cost-risk balancing approach. The model searches for the identification of optimal decision rules by balancing the risk of water shortages and the operating costs of pumping stations. Scenario optimisation provides ‘barycentric’ values that define the activation threshold by comparing hydrological synthetic series results. A multi-objective approach is also required in order to balance energy cost minimisation requirements and a reduction of damage needs that can be caused by water shortages. Consequently, a scenario optimisation has been developed considering the multi-objective and cost-risk balancing problem. A model application has been developed optimising water management and energy costs in a real water system with shortage risks in the South Sardinia (Italy) region.

A real-time, rapid emergency control (EC) model is proposed to cope with sudden water pollution accidents in long-distance water transfer projects. The EC model outputs the method of EC based on pollutant properties. A generalized form of EC model is proposed and tested with a demonstrative project. The rapid prediction formulas of emergency control parameters (ECPs) are proposed under different states of water diversion. The closing times of check gates and the pollution range are calculated by the rapid prediction formulas of ECPs. A case study is examined under the scenario of a sucrose spill in a demonstrative project conducted in the Fangshui to Puyang channel of the Beijing–Shijiazhuang Emergency Water Supply Project in the middle route of the South-to-North Water Transfer Project. The relative errors of peak concentration and arrival time of peak concentration are less than 20%. However, we could not use an actual toxic soluble pollutant to validate the EC model, so we performed the experiment with sucrose to test the EC model based on its concentration variation. The final result shows that the model is able to play a fundamental role in the decisions involved in the Emergency Environmental Decision Support System.

The world’s largest dam—the Three Gorges Dam (TGD)—has been in operation for more than 10 years. While the recent shrinkage of large lakes and increased severe droughts in the downstream have been subjectively ascribed to TGD, empirical support based on thorough analysis is still lacking, leaving a gap for ecologists to quantify the TGD impacts on the surrounding landscapes. This study aims to quantify the impacts of TGD water impoundment on downstream landscapes in terms of lake shrinkage and severe droughts. We have incorporated the recent findings and conducted a comprehensive analysis based on long-term datasets and contrasting scenarios with and without the presence of TGD. The datasets were constructed from hydrological measurements, a hydrodynamic model, and satellite data retrieval techniques. Here we show that, in addition to natural variations due to climatic conditions, TGD water impoundment has indeed weakened river’s ability in preventing backflows from its connected lakes directly contributed to their shrinkage. The impoundment substantially increased the intensity and severity of droughts downstream, and may have produced a cluster of impacts on the changing landscape. Our finding provides needed information for assessing TGD’s impacts on environmental services in the region, and raises serious concerns with the ongoing large-scale hydraulic project—China’s South-to-North Water Transfer Project—which will further reduce the flow of the Yangtze River.

The middle route of the south–north water transfer project (SNWTP) was built to relieve the pressure of increasing water demand in northern China. Serving as one of the major storage systems, optimal operation rules should be proposed promptly for Danjiangkou Reservoir, completed by a heightening project. In this paper, in order to seek out the optimal operation rules for Danjiangkou Reservoir, a multi-objective optimal operation model is developed, considering the inflow uncertainty, multi-year regulation cycle and water supply for the SNWTP. Three evaluation indexes (hydropower generation, water impoundment condition and shortage index) are adopted to assess the impacts of three influence factors (starting regulation level (SRL), inflow condition and flood control level) on Danjiangkou Reservoir operations. Finally, some critical operation strategies for Danjiangkou Reservoir are proposed. The results show that the optimal SRL for Danjiangkou Reservoir is 158 m and the recommended range of the water level at the end of the first year varies between 162–166 m (very wet), 164–166 m (wet), and 162–164 m (normal) on the basis of setting 158 m as the SRL.