Storage Volume Research Articles

Temporal and spatial distributions of flood water storage volume of the main river and tributaries in the Ishikari River basin

Temporal and spatial distributions of flood water storage volume of the main river and tributaries in the Ishikari River basin

Model‐based estimation of long‐duration design precipitation for basins with large storage volumes of reservoirs and snowpacks

Model‐based estimation of long‐duration design precipitation for basins with large storage volumes of reservoirs and snowpacks

Monitoring dynamics of Kyagar Glacier surge and repeated draining of Ice-dammed lake using multi-source remote sensing

Glacier surges, a primary factor contributing to various glacial hazards, has long captivated the attention of the global glaciological community. This study delves into the dynamics of Kyagar Glacier surging and the associated drainage features of its Ice-dammed lake, employing high temporal resolution optical imagery. Our findings indicate that the surge on Kyagar Glacier began in late spring and early summer of 2014 and concluded during the summer of 2016. This surge resulted in the transfer of 0.321 ± 0.012 km3 of glacier mass from the reservoir zone to the receiving zone, leading to the formation of an ice-dammed lake at the glacier's terminus. The lake experienced five outbursts between 2015 and 2019, with the largest discharge occurring in 2017. And the maximum water depth during this period was 112 ± 11 m, resulting in a water storage volume of (158.37 ± 28.32) × 106 m3. On the other hand, our analysis of the relationship between glacier surface velocity and albedo, coupled with an examination of subglacial dynamics, revealed that increased precipitation during the active phase of the Kyagar Glacier results in accumulation of mass in the upper glacier. This accumulation induces changes in basal shear stress, triggering the glacier's transition into an unstable state. Consequently, glacier deformation rates escalate, surface crevasses proliferate, potentially providing conduits for surface meltwater to infiltrate the glacier bed. This, in turn, leaded to elevated basal water pressure, initiating glacier sliding. Furthermore, we postulated that the repetitive drainage of Kyagar Ice-dammed lake was primarily influenced by the opening and closing of subglacial drainage pathways and variations in inflow volumes. Future endeavors necessitate rigorous field observations to enhance glacier surge simulations, deepening our comprehension of glacier surge mechanisms and mitigating the impact of associated glacial hazards.

Spatiotemporal patterns of water volume and total organic carbon concentration of agricultural reservoirs over South Korea

Lacking of available water quality data causes the limited understanding of the coupled dynamics of hydrologic and nutrient cycles in lakes and reservoirs and along river streams. This study conducts the rotated Principal Component Analysis (rPCA) of water volume and total organic carbon (TOC) concentration data from ∼2200 agricultural reservoirs in South Korea to extract the major modes of their spatiotemporal variability. Over 2020–2022, the total TOC load in the reservoirs ranges between 1,165 and 1,492 tons (289 and 360 Mtons of water storage volume; 3.54 and 4.60 mg/L of TOC concentration). The first rPCA mode is assoicated with a decreasing trend of water level (38 % of the explained variance) and increasing trend of TOC concentration (27 %) over the southern Korea region, where the TOC concentration increased during the 2022 drought. The second rPCA mode is associated with interannual variability of water level (25 %) and TOC concentration (18 %) over the central Korea region. This study found a marginal relationship between paddy field area and TOC concentration and their regime shift to high TOC concentration during the 2022 drought, which was a potential cause of the increased TOC concentration in 2022. This study provided observational evidence of interactions between water volume and TOC concentration during a severe drought, suggesting a possible shift of the role of agricultural reservoirs to carbon source.

Design Issue Analysis and Operation Effect Evaluation of Large-Scale Storage Tank

In order to address the issue of combined sewer overflows (CSOs), W city has constructed a large-scale storage tank with a volume of 220,000 m3. The storage tank is planned for CSO control in the near term and stormwater runoff pollution control in the long term. However, the actual operation of the storage tank is unsatisfactory. This paper elucidates the design scheme and operation mode of the tank and analyzes the challenges encountered during its design and operation. A storm water management model (SWMM) model was constructed to simulate the effect of the storage tank working in a combined sewer system (CSS), a separate sewer system (SSS) and a decentralized storage situation. This study determined that during the 2022 rainy season, the actual reduction in pollutants by the storage tank was only about 60% of the designed value. As a result, the inadequate treatment capacity of the downstream wastewater treatment plant (WWTP) resulted in the water being retained in the tank for a long time, leading to unsatisfactory operation outcomes. If the storage tank works in SSS and the problem of water retention can be solved, it could reduce the total runoff volume by 30% and the total amount of pollutants by 40% during the same rainy season. At the same time, under the premise of constant total storage volume, if decentralized storage tanks were used to control runoff pollution, the reduction effect can be increased by up to 11.6% compared with that of the centralized storage.

Field tests of geological storage of CO 2 at the Otway International Test Centre, Australia: trapping and monitoring the migrating plumes

The capture and geological storage of CO 2 is essential for net zero. Large volumes of secure subsurface storage will be required, much in unexplored saline aquifers. At the Otway International Test Centre we have executed a series of storage tests, including geophysical surveys, geochemical and petrophysical characterization, drilling and instrumenting six deep wells and conducting two intensively monitored injections each of 15 Kt CO 2 . We summarize the execution and outcomes to draw out the implications for larger-scale storage and for migration trapping of CO 2 plumes. Immobilization of most of the plume is essential for long-term safety. Suitable saline aquifers should have sealing caprocks but need not have structural traps. Buoyant CO 2 could move kilometres beneath the seal, with immobilization occurring by capillary forces and dissolution. Predicting and monitoring plume behaviour with practical methods integrated with risk management will be necessary. We characterized and monitored migration trapping, demonstrated plume immobilization, and tested monitoring methods tailored to large saline aquifers. We developed pressure tomography and continuous seismic monitoring; these provide less detailed information than conventional methods but can be targeted at risks. Passive methods, such as the seismic response to earthquakes, can also act as sentinels for specific events. These methods can bridge the ‘monitoring gap’ between detailed but infrequent methods and more frequent but simpler methods and the results will enable better trade-offs between cost, complexity and risk for a technology crucial for controlling CO 2 levels in the atmosphere. Supplementary material : Detailed descriptions of unpublished modelling are available at https://doi.org/10.6084/m9.figshare.c.7148197

DATA FINDING, SHARING AND DUPLICATION REMOVAL IN THE CLOUD

Deduplication involves eliminating duplicate or redundant data to reduce stored data volume, commonly used in data backup, network optimization, and storage management. However, traditional deduplication methods have limitations with encrypted data and security. The primary objective of this project is to develop new distributed deduplication systems that offer increased reliability. In these systems, data chunks are distributed across the Hadoop Distributed File System (HDFS), and a robust key management system is utilized to ensure secure deduplication with slave nodes. Instead of having multiple copies of the same content, deduplication removes redundant data by retaining only one physical copy and referring other instances to that copy. The granularity of deduplication can vary, ranging from an entire file to a data block. The MD5 and 3DES algorithms are used to enhance the deduplication process. The proposed approach in this project is the Proof of Ownership (POF) of the file. With this method, deduplication can effectively address the issues of reliability and label consistency in HDFS storage systems. The proposed system has successfully reduced the cost and time associated with uploading and downloading data, while also optimizing storage space. Key Words: Cloud computing, data storage, file checksum algorithms, computational infrastructure, duplication.

Optimization of Pengga Reservoir in The Mandalika Special Economic Zone for Irrigation and Water Supply

Mandalika Special Economic Zone is tourism area that is expected to improve the economy in West Nusa Tenggara Province. To support these activities, an allocation of domestic water needs of 200 liters second -1 is needed. The potential availability of water in the Pengga Reservoir is planned to be a source of domestic water needs in the Mandalika Special Economic Zone. Pengga Reservoir has an effective storage volume of 17.26 MCM. Potential water resources in Pengga Reservoir are obtained from reservoir outflow upstream and lateral inflow from several tributaries. The study was carried out to determine the reservoir storage capacity to meet domestic water needs and irrigation water needs covering an area 3189 ha. The cropping pattern used in the Pengga irrigation area is Paddy – Paddy/Secondary Crops – Paddy/Secondary Crops. To optimize the potential of water resources in the Pengga Reservoir, a linear programming optimization method is used. Indicators of the success of optimization calculations are indicated by the value of cropping intensity, k factor and reliability that have met the minimum limit value. The k factor value for irrigation water needs is 0.70 and domestic water needs is 0.85. Based on the optimization results, it is known the largest annual cropping intensity value occurs in the November I planting season. This conclusion can be seen from the comparison of annual cropping intensity values for the November I and November II planting schedules for the dry year inflow discharge scenario of 99.98% and 97.22% respectively. The cropping intensity value in the November I planting season is greater than November II, namely 100% and 97.25%, for the normal year discharge inflow scenario. This study provides an information for policy makers can use the November I planting schedule to obtain values for maximum cropping intensity and domestic water requirements.

The influence of microtopography to road inundation caused by extreme flood

Microtopography plays a critical role in road inundation during urban flood events. The microtopography in this paper was defined as terrain-scale features that encompass surface roughness, slope, road network and urban building layout. This paper aims to explore the mechanism of depression storage and road inundation under different microtopography. Simulations under 4 rainfall intensities (144.0– 182.88 mm/h) and 14 slope combinations (four transverse slope and five longitudinal slope) were implemented in an 800 by 70 cm local model. The correlation heat map directly reflected that longitudinal slope had higher influence on drainage than other factors. Then real topographical and hydrological data was applied to predict road inundation with five different extreme rainfall events in Jiangning District (Nanjing City, China). The microtopography characteristics of frequent inundation road were extracted, which further verified the conclusions of the local model. Results show that: the microtopography depressions drainage process could be divided into six main stages: filling stage, interaction stage, unstable drainage stage, stable flow stage, drainage stage and stage of drainage end. Water was stored on depressions of road, and the storage volume and discharge efficiency were affected by the surface relief and slope. The emergence of slope provided an altered path and power for water drainage. Only 0.3 % slope could contribute a 28.4 % to discharge efficiency. Upon comparation, the best combination for drainage was 2.0 % transverse slope with 3.0 % longitudinal slope. These findings provided meaningful insights and perspectives for urban flood hazard mitigation and were a more detailed reference for road design.

Перспективы исследований фосфогипса как материала для строительства

Objective: analytical investigation of the potential use of hemihydrate (CaSO4 · 0.5H2O) and dihydrate (CaSO4 · 2H2O) calcium sulfate — phosphogypsum — a waste in the production of mineral fertilizers, as a construction material for the construction of roads, soil structures, material for the restoration of roads in the areas of repair of utility networks, as well as unloading of developed landfills for the storage of waste from processing phosphorus ores of chemical enterprises operating in the Russian Federation. Methods: analysis of the current situation at landfills of industrial enterprises, analysis of the knowledge of the issue of utilization and processing of phosphogypsum, as well as analytical (calculation) assessment of the possibility of replacing bulk materials (sand, crushed stone) with phosphogypsum common in construction. Results: this article discusses issues related to the assessment of the possibility of using phosphogypsum with a decrease in its local concentration in the zones of its application, as well as with the use of waste stored at landfills for many years. The considered options for prospective use of the material, which make it possible not only to preserve, but also to increase the operational characteristics of roads and other soil structures, while eliminating the potentially harmful effect of the material during operation associated with its dusting during storage. Practical significance: analysis of the current situation indicates that due to the active production in the Russian Federation, a huge amount of waste from such production — phosphogypsum — accumulates on the territory of industrial enterprises engaged in the processing of phosphorus ores and landfills assigned to these enterprises. The annual utilization of phosphogypsum at such enterprises is estimated at hundreds of thousands and millions of tons — huge dumps are formed, which pose a danger both from the point of view of groundwater pollution and from the point of view of man-made safety. With such large volumes of concentrated storage, the volumes of substances entering the soil and groundwater may repeatedly exceed the permissible values, but at the same time, with a lower concentration, the ingress of these substances into the soil may not only not harm the environment, but also have a positive effect in terms of increasing yield. The use of waste from such production facilities in road construction will solve the problems associated with the disposal of phosphogypsum.

KAJIAN PENANGGULANGAN BANJIR DENGAN PERBAIKAN PENAMPANG SITU PONDOK JAGUNG

Flood mitigation of Situ Pondok Jagung caused by it’s inadequate capacity to handle water, resulting in overflow and localized inundation, this study employed an analytical and simulation modeling approach using SWMM 5.1 software. The modeling process required input data such as Rain Gage, Subctachment, Conduit, Juction, Storage Unit, and Outfall. The analysis and modeling revealed a capacity shortfall, evident from the floodwater levels observed in Situ Pondok Jagung. The analysis and modeling results indicate an excess capacity of the storage capacity, as evidenced by the flood water elevation in Situ Pondok Jagung. Thus, the hydraulic analysis in SWMM 5.1 considers two design conditions: the existing condition with a height of 1.5m, showing a total water discharge of 103,75 m3/s, and a storage volume of 119.250 m2. For the planned condition using trial and error experiment, dredging was performed to a depth of 20cm, and an additional 50cm in height was added to the levee. As a result, the height of Situ Pondok Jagung became 2,2m, with zero overflow, and a storage volume of 174.900 m3. This represents a reduction of 40% and indicates that this planning effort could be considered as an alternative solution.

Effects of irrigation dams on riverine biota in mountain streams

Mountain streams harbor unique biodiversity and provide essential ecosystem services to human societies. Yet, these ecosystems face numerous threats, such as the construction of dams and land use changes, leading to rapid habitat degradation, water pollution, and biodiversity loss. In this study, we assess the effect of irrigation dams on mountain riverine biota using traditional biotic indices and trait-based approaches. We selected diatom and macroinvertebrate communities surveyed between 2015 and 2017 in mountain streams located in different regions in northern Spain (Cantabrian Cordillera, Iberian System, and Pyrenees) under natural and altered flow conditions (i.e., downstream of irrigation dams). Hydrological and biological changes related to the presence of dams, the mountain range, and the interaction between these two factors were identified. Summer flows, frequency of high flow events, and minimum annual flows timing were significantly affected by irrigation dams, independently of the region. Winter flows, the magnitude of high flow extremes, and the number of flow rises and falls varied significantly with the dam-mountain range interaction. The frequency and duration of flow pulses depended on the mountain range only. In the Cantabrian Cordillera, a region with larger reservoirs (>150 hm3), impacted sites showed a marked inversion of the seasonal flow patterns (i.e., increased summer flows but reduced winter flows). In the other mountain ranges, reservoirs had smaller storage volumes and multiple purposes, causing significant flow change frequency variations. Diatom traits, taxonomic richness, diversity, and IPS score varied with dam presence and mountain ranges, while macroinvertebrate traits and biotic indices responded weakly. These findings suggest that diatom communities might be more sensitive to hydrological alteration, while macroinvertebrates might be more influenced by space-related factors, such as biogeography and dispersal, overriding dam-related impacts. Furthermore, dam-related changes in ecosystems may depend not only on the presence of dams and their characteristics (e.g., reservoir size and operation), but also on local conditions and biogeography. Our findings emphasize that, when using pre-existing biomonitoring datasets, although some dam-related patterns emerge (e.g., with diatoms), other patterns may be constrained by the datasets’ low spatio-temporal coverage and taxonomic resolution, highlighting the need of well-structured study designs.

Velocity and Temperature Simulation for a Cylindrical Regenerative Thermal Oxidizer.

The cylindrical regenerative thermal oxidizer (CRTO) came into being later than the three-chamber regenerative thermal oxidizer (TRTO). Compared with TRTO, CRTO has a smaller size and a larger regenerator volume for absorbing and releasing heat. There are few studies on CRTO despite its numerous applications. A CRTO was selected in industrial applications for simulation research. The velocity and temperature of the CRTO were investigated after error analysis of industrial and simulated data. It was found that the velocity and temperature in the regenerative chamber had obvious stratification and gradients after homogenization by the regenerator unit. The velocity and temperature distribution in the oxidation chamber were independent of the position of the CRTO inlet and outlet or the structure below the regenerator, and there were identical periodic changes in each period. A TRTO with primary parameters as those of the CRTO was employed for comparison. The time of the intake and exhaust periods of a CRTO regenerative chamber were 30 s longer than those of a TRTO. The regenerator volume of heat storage used by CRTO for heat exchange increased by 1/6 compared to that of TRTO at the same total regenerator volume. Simulation shows that CRTO had a more uniform velocity and temperature in the regenerative chamber compared to those in TRTO, increasing by approximately 2%; the thermal efficiency is higher, with an average increase of about 3%.

Introduction of a modular passive rainwater harvest system for existing buildings

ABSTRACT In urban areas facing water stress, rainwater harvesting is essential. This paper proposes a passive rainwater harvesting system as a viable alternative for ensuring a clean water supply. The study introduces an innovative and original design for rainwater harvest. The presentation of the system is performed by analysis of efficiency and reliability of the system analytically. The optimal storage volume is determined through a 22-year precipitation data analysis using the mass balance method, ensuring high efficiency. Payback periods for various consumptions and tank sizes are calculated, showing shorter periods compared to active systems since the proposed system does not use electrical energy. The results demonstrate that 350 m3 of storage volume can assure 99% efficiency when potable water consumption is 0.01 m3/person/day. The payback period of the system was calculated to be between 5 and 10 years. The proposed system can be considered as an appropriate rainwater harvest alternative for existing buildings.

CLOUD BASED DUPLICATION REMOVAL SYSTEM

Deduplication involves eliminating duplicate or redundant data to reduce stored data volume, commonly used in data backup, network optimization, and storage management. However, traditional deduplication methods have limitations with encrypted data and security. The primary objective of this project is to develop new distributed deduplication systems that offer increased reliability. In these systems, data chunks are distributed across the Hadoop Distributed File System (HDFS), and a robust key management system is utilized to ensure secure deduplication with slave nodes. Instead of having multiple copies of the same content, deduplication removes redundant data by retaining only one physical copy and referring other instances to that copy. The granularity of deduplication can vary, ranging from an entire file to a data block. The MD5 and 3DES algorithms are used to enhance the deduplication process. The proposed approach in this project is the Proof of Ownership (POF) of the file. With this method, deduplication can effectively address the issues of reliability and label consistency in HDFS storage systems. The proposed system has successfully reduced the cost and time associated with uploading and downloading data, while also optimizing storage space. Key Words: Cloud computing, data storage, file checksum algorithms, computational infrastructure, duplication.

Development of an analytical solution for optimum design of RWH systems—A case study in Guangzhou

AbstractThe implementation of rainwater harvesting (RWH) has emerged as a key strategy to cope with the water crisis in urban areas. However, the required design parameters of the RWH system in different buildings vary widely because of the differences in architectural characteristics. In this paper, the relationships between the building characteristics parameters and the optimal tank (Tc) capacity are investigated by simulating the RWH system for more than 120 buildings at different locations in Guangzhou. Explicit expressions relating the optimal storage volume of RWH systems to building characteristics are derived based on nonlinear regression analysis. A set of bivariate exponential equations for estimating the optimal tank size under different building conditions was obtained. The model has a MER of less than 10% for buildings with a C/D ratio between 17.5 and 85. In Guangzhou, the unit cost of an RWH system can be reduced to CNY 2.62/m2 with optimally designed tanks.

Thermal performance of an aquifer thermal energy storage system: Insights from novel multilateral wells

Aquifer thermal energy storage (ATES) is an effective time-shifting thermal energy storage technology. Considering the enormous technical and economic input of the well pattern layout, the storage volume of a single well needs to be improved. This study proposes a novel aquifer thermal energy storage system in which several multilateral wells are side-tracked from the vertical well in the aquifer. Radial branches can enhance the connectivity of the wellbore to the aquifer. The research creates an unsteady-state 3D model to analyze the novel ATES system's fluid flow and heat transfer performance. The model is verified using experimental data. The temperature and pressure fields of the multilateral-well ATES are analyzed. Additionally, the effects of injection rate, radial branch length, number of radial branches, aquifer temperature, and aquifer thickness on system performance are studied. According to the research results, compared with the vertical wells, the performance coefficients of the multilateral hot well and cold well increase by 113.06 and 39.25, respectively, and the economic efficiency increases by 14.19% and 23.87%, respectively. The findings can provide a crucial reference for scientific research and the application of aquifer thermal energy storage systems with multilateral wells.

Variable analysis for supporting reservoir impounding modeling

The impounding stage of the reservoir is a stage after the implementation of dam construction is finished. The process of reservoir impounding is started by closing the tunnel diversion gate and the elevation of the water level will be moving up slowly. The speed of the increasing reservoir water level elevation is affected by the dry season or rainy season, so it is arranged in such a way for obtaining the daily increase is not more than 1.0 m/day, due to dam safety. This research intends to build this modeling, at first by studying which variables are affecting in order to get the safe period of impounding. The methodology consists of a correlation analysis of inflow, outflow, and the ratio between storage volume and inflow volume to the optimal impounding equation. The statistical hydrology approach is used in this modeling that will assess the 7 observed reservoir impounding which is started from base elevation until Full Supply Level (FSL). This modeling will help in decision-making about the selection of the safe and optimal period of reservoir impounding. At the end of impounding, the reservoir will be full and it starts to be allocated regarding the utilization that has been designed.

Cataract surgery and environmental sustainability: a comparative analysis of single-use versus reusable cassettes in phacoemulsification

ObjectiveTo compare sustainability, financial implications and surgical efficiency of two phacoemulsification cassette systems for cataract surgery: a machine with single-use cassettes and another with daily, reusable ones.MethodsObservational study involving retrospective...

Restoring Predevelopment Hydrology with Smart Stormwater Controls in Aiken, South Carolina

For decades, large quantities of stormwater runoff from the City of Aiken flowed at destructive velocities (exceeding 5 ft/s) into the Sand River, deeply eroding the channel in the downstream Hitchcock Woods. From 1990 to 2015, the City of Aiken commissioned several consultants to produce over a dozen studies to investigate viable solutions for the destructive erosion. Upon the recommendation from a collaborative Stormwater Task Force, the City of Aiken approved a stormwater implementation plan in 2018 which recommended 20 capital improvement projects sized to capture 58 ac-ft of stormwater in order to restore the river’s predevelopment hydrology, with a goal of reducing stormwater velocities in the Sand River to reflect design considerations in the National Engineering Handbook (between 2.0 ft/s for fine sand channels and 4.0 ft/s for coarse sand channels). In November 2023, the City of Aiken completed construction on two underground detention vaults with a total storage volume of 25 ac-ft. These vaults were designed to capture stormwater runoff before it enters Hitchcock Woods and infiltrate as much stormwater runoff as possible; any additional stormwater will be released at a reduced flow rate compared to existing conditions. The 10-year, 24-hour storm event was selected to size the vaults because it was an achievable metric given numerous constraints such as available land, impacts to existing infrastructure and environmental resources, and available funding. The 10-year event also corresponded to typical stormwater requirements for new development. The vaults utilized the largest height, 15 feet, available for precast underground storage vaults in the marketplace. In addition to providing stormwater management below ground, a new public park was constructed on top of the buried vaults to be used as a gateway between the Hitchcock Woods and the City of Aiken.