Water-filled Conditions Research Articles

Design and Development of a Portable Water Ionizer Based on the Internet of Things (IoT) with Battery Utilization and Portability Capability

A portable water ionizer has been successfully developed as an innovative solution to provide healthy and high-quality water conveniently while traveling. The device utilizes six 18650 lithium-ion batteries connected in series with a maximum voltage of 25.2 Volt DC and a current capacity of 1500 mAh as the main power source for the water electrolysis process. Additionally, two 8.4 Volt DC batteries are used to power the microcontroller and sensors. The total power required for the entire device is approximately 13.274 Watt, allowing the device to operate for approximately 3 hours. Portability testing was conducted through a questionnaire involving the participation of 22 respondents. The majority of respondents, 15 out of 22, stated that the device is easy to carry while traveling and demonstrates good portability. This can be attributed to its compact dimensions (17 cm x 13 cm x 37 cm) and relatively light weight (1.5 kg in dry condition and 2.5 kg in water-filled condition). Another advantage of the device is its ability to operate without a connection to household electricity, making it a practical and portable option for users to carry while traveling. The positive results of the portability testing confirm that the portable water ionizer successfully meets the desired portability standards. With its easy-to-carry design, the device can be an efficient and convenient solution for individuals who travel frequently and prioritize the quality of the water they consume.

An innovative deep neural network coordinating with percussion-based technique for automatic detection of concrete cavity defects

Cavity defects are usually invisible in concrete, failure to detect and repair them in time could significantly weaken the load-bearing capacity of engineering structures, potentially threatening the structural safety during the construction and operation periods. Therefore, it is essential to explore efficient approaches to detect concrete cavity defects. In this study, we propose a novel method to detect concrete cavity defects based on percussion and deep learning (DL) techniques. First, the percussion sound dataset was collected from concrete specimens with different types of precast cavity defects. Next, an innovative DL framework named the multi-scale convolutional bidirectional memory network (MCBMNet) was developed for classifying these percussion sound signals associated with specified concrete cavity defects. The MCBMNet utilizes the multi-scale convolutional operation to generate various scale features directly from raw percussion sounds, and then employs the bidirectional memory units to capture intrinsic feature connections and enhance feature separability, thus improving prediction accuracy and robustness. Finally, two experimental cases, including water-free and water-filled conditions, were designed to test the feasibility of the proposed method considering the influences of humidity environment in reality. Experimental results well demonstrate the excellent performances of the proposed MCBMNet for concrete cavity defect detection, with its average accuracy over 98% in both cases. Additionally, the anti-noise capacity and adaptability of MCBMNet were thoroughly investigated, which outperforms conventional learning algorithms.

Mechanical properties and durability of injected SCC panels by epoxy against freezing and thawing

Repairing cracks in concrete structures exposed to freezing and thawing cycles by injecting epoxy resin and the main factors affecting it, such as epoxy viscosity, crack width, and the crack's moisture content, has been studied in a few research.This paper utilized commercial epoxy resins with high, medium, and low viscosities to inject through simulated cracks. In addition, repair methods were tested and evaluated by injecting epoxy resins in dry, damp, wet, and water-filled conditions. Furthermore, two crack widths (0.5 and 0.8 mm) were simulated on the specimens, and the effects of the repairing materials' thickness on the rehabilitation success were examined. The specimens’ durability with 24 cycles of freezing and thawing was investigated.Results demonstrate that water's presence in different situations, especially the water-filled ones in the interfacial zone, deteriorates the bond characteristics; Contrastly, the results were better in the wet situation. It can be concluded that injecting in the dry situation is optimized. The results showed that curing in lower temperatures takes longer than in higher temperatures. Moreover, a correlation was observed between the viscosity and its effect on tensile bond strength and actual shear strength in the slant shear test. It was found that the low-viscosity resin showed better performance than the high-viscosity resin overall. Moreover, the low-viscosity resin achieved 25% more shear strength in the slant shear test than the high-viscosity. In the freezing and thawing cycles, the injection was stable only in dry cracks, and in other moist conditions, the samples failed the freezing and thawing cycles.

ANALISIS KAPASITAS TAMPUNGAN DAN KINERJA WADUK UNTUK MEMENUHI KEBUTUHAN AIR TANAMAN NANAS DI PT. GREAT GIANT PINEAPPLE

The reservoir is one of the water sources that can be used for irrigation activities. PT. Great Giant Pineapple utilizes the reservoir function to provide water for irrigation activities. In an era that is increasingly developing now, many things can support success in the agricultural sector. Cropwat for window 8.0 application and ArcGis is one proof of technological advancements in this era. The results of this study were to determine the capacity of a reservoir by using two different methods namely bathymetry and DEM and to find out the performance of the reservoir used for irrigation activities based on pineapple plant water requirements.. This research is located in PT. Great Giant Pineapple, Terbanggi Besar, Lampung, conducted in October until November 2019. Based on the results of research that has been done, it is recommended to use the bathymetry method for reservoirs with water-filled conditions and using the DEM method for water-empty reservoirs and it is known that the performance of a reservoir will be affected by the amount of outflow and inflow that occurs in the reservoir and the large reservoir capacity.

Shear Rate Effect on Strength Characteristics of Sandy Soils

In this study, the effects of different shear rates during direct shear tests on variations in the strength characteristics were investigated for the sand samples of various particle size distribution. Direct shear tests were carried out at nine different shear rates ranging from 0.05 to 5 mm/min under normal stresses of 54.5, 109, and 218 kPa. Both sample groups were tested under a condition of defined water content and in a water-filled condition. Results show that with increasing shear rate, the internal friction angle and peak shear strength values increased. The increase in the internal friction angles and peak shear strengths were particularly evident for shear rates higher than 1 mm/min. Even though the effect of grain size on the variation in strength parameters due to shear rate is limited for the soils examined in this study, the effect should be considered.

Dynamic and thermal characterization of additively manufactured pressure-fed flexures with internal fluidic channels

This paper presents the dynamic and thermal characteristics of pressure-fed flexures with the additively manufactured internal fluidic channels under various pressure and fluidic conditions. Additive manufacturing technology makes use of the mechanical design flexibility that can effectively control the material distribution in terms of stiffness and damping of the flexures. Five different fluidic channel geometries (circular, semicircular, inverse-semicircular, triangular, and inverse-triangular) with the same cross-sectional area were designed and fabricated inside of one-dimensional cantilever beams (10 × 24 × 100 mm3). Stiffness, damping ratio and natural frequency of each cantilever according to varying air pressure condition from 14.7 psi (unpressurized) to 75 psi and water-filled condition were characterized, and at the same time, dynamic behaviors of each cantilever were identified by using dynamic signal analyzer. Furthermore, the thermal behavior of the channel with respect to unpressurized air, 40 psi air, and water-flowing condition was analyzed. As a result, the internal channel geometry and filled-in media in the channel have significant influences to determine the dynamic and thermal characteristics of flexures. These results can be applied to the design of flexure mechanisms that can adaptively control or compensate for their dynamic behaviors in an easy, convenient and low-cost manner.

Performance of the Prestressed Composite Lining of a Tunnel: Case Study of the Yellow River Crossing Tunnel

This paper presents the performance of a new prestressed composite lining applied in shield tunnels for water conveyance. The Yellow River Crossing Tunnel of the Middle Route Project of the South-to-North Water Division Project is adopted in this study as a case, and a three-dimensional finite element model is established to analyse the stress distribution and deformation feature of the prestressed composite lining when the tunnel is under the assembly condition, the tension condition and the water-filled condition. The finite element model is verified by comparing with the results of the full-scaled simulation experiment. The calculation and analysis results reveal that further open of the segmental joint gaps can be limited and full circumferential compression of the secondary lining can be realized when the tunnel is under the water-filled condition, which are conducive to long-term operation of the prestressed composite lining. The membrane has a significant effect on preventing stresses from being transmitted between the segmental lining and the secondary lining. The numerical calculations are verified by the results of the full-scaled simulation experiment, and the three-dimensional numerical model combined with the analysis method used can simulate the structural characteristics and the bearing mechanism of the prestressed composite lining.

New results on the hydrodynamic behaviour of fossil Nummulites tests from two nummulite banks from the Bartonian and Priabonian of northern Italy.

Settling velocities of 58 well-preserved tests of fossil Nummulites were experimentally determined using a settling tube. The tests were collected from the nummulite banks of Pederiva di Grancona (A forms of N. lyelli and N. striatus, Middle Eocene) and San Germano dei Berici (A and B forms of N. fabianii, Late Eocene), both in the Berici Mts. (Veneto, northern Italy). The data were compared with estimated settling velocities that the same specimens might have had in life conditions. This was done by reconstructing their densities simulating water-filled condition and, to simulate post-diagenetic effects, under calcite-filled condition. These simulations show that A and B forms, even if they greatly diverge in shape, volume and size, still possess comparable settling velocities, and that each nummulite bank is characterized by specific hydrodynamic parameters. The use of settling velocity as a parameter to quantify the hydrodynamic behaviour of particles in seawater enables estimation of palaeoenvironmental conditions such as depth, substrate and the energy scenario. Such information is useful in obtaining further insights into the genesis of nummulite banks, the autochthony or allochthony of which is still being debated. Our results point to an autochthonous interpretation.

Numerical Modeling of P-Waves for Shallow Subsurface Cavities Associated with Old Abandoned Coal Workings

Subsidence is a major environmental hazard associated with shallow abandoned coal workings in the Raniganj coalfield of eastern India. Most of the old abandoned coal workings are poorly documented. There is a need to detect and quantitatively infer these workings through some inexpensive geophysical techniques. High resolution reflection seismic is one such technique that suits this problem because of its sensitivity to the presence of voids through direct reflection and scattering properties of P waves. In this study, cavity identification and location remained uncertain on the basis of 2-D stacked sections in the presence of noise. To improve interpretation, a 2-D zero-offset finite-difference model was developed to characterize the seismic signature over the cavities. The model represents a rectangular cavity associated with air-filled and water-filled conditions in a multilayered interface. A seismic migration technique is also applied to the zero-offset sections to further improve the interpretation. The numerical results show the top and bottom of the cavities clearly with their shape properly delineated for air-filled cavities. The base of water-filled galleries are detected as strong positive reflections.

Mineshaft imaging using surface and crosshole 3D electrical resistivity tomography: A case history from the East Pennine Coalfield, UK

Hidden mineshafts located in urban areas are a significant problem across much of the industrialized world. Electrical resistivity tomography (ERT) is a technique that can detect and characterize hidden mine entries by exploiting resistivity contrasts between the shaft and surrounding materials, resulting from either compositional or structural differences. A case study is presented in which both surface and crosshole 3D ERT surveys are used to image a hidden backfilled mineshaft at a built environment site, situated on Carboniferous Lower Coal Measures strata in the UK. Backfilled shafts generally present the greatest challenge for detection using geophysical methods, as contrasts between the fill and bedrock are typically low compared to air or water-filled conditions. Nevertheless, the shaft in this case was identified by both the surface and crosshole 3D surveys. The shaft appeared as a strongly resistive anomaly relative to background materials, which we interpreted as resulting from the disturbed fabric of the fill materials rather than any significant compositional differences. The study highlighted the respective strengths and weaknesses of the surface and crosshole ERT methodologies for this type of problem. The surface survey, which covered a non-rectangular area to accommodate irregular boundaries and other physical obstructions, provided a relatively rapid means of investigating the study site. However, this method had a limited depth of investigation and was constrained in its coverage by the locations of buildings. By contrast, the 3D crosshole method was able to image the shaft to the level of the deepest borehole electrodes. Although crosshole ERT is too expensive to be used for large-scale mineshaft surveys, this study clearly demonstrates its suitability for targeted investigations where surface methods cannot be deployed, such as scanning beneath surface structures or in situations where it is essential for resolution to be maintained with depth.

Properties of cylindrical shells submerged in seawater

The following work is based on the age-old Archimedes’ principle of submerged bodies. Today, many discussions and papers exist on submersion. It shows that the submerged weight parameter cannot be directly incorporated into the design process. In this paper the diameter-to-wall-thickness ratio has been identified as the constraint variable in the optimization process, and has appropriately been used in describing properties of submerged cylinders in seawater. Simple dimensionless equations, in terms of diameter-to-wall-thickness ratio have been developed and used to compare the behavior of many coated and uncoated shell sections, in empty and water-filled conditions. This presentation of the properties of submerged cylindrical shells demonstrates how the idea formulated millennia ago can be configured to yield new results benefiting the offshore industry.

The Use of Pulsed-Neutron Capture Logs for Reservoir Management in the Midway-Sunset Field

Summary Systematic time-lapse pulsed-neutron capture (PNC) logging was conducted during a 2-year steam-foam mechanistic field trial in the steamflooded Monarch reservoir, which is composed of interbedded sandstones, conglomerates, siltstones, and diatomaceous mudstones. Observation wells were drilled with one continuously cored through the reservoir interval and two emptied to facilitate better temperature logging. Uncalibrated PNC log responses in the air-filled wells were normalized to water-filled conditions and were used to generate a series of steam/gas saturation profiles that indicate clearly the dynamics of the fluid and foam in the reservoir during the experiment. Correlations between neutron capture cross sections (sigma), mineralogy, and rock chemistry from core samples were examined for additional use of the PNC logs for steamflood reservoir characterization. Sigma was found to increase with increasing clay/mica content and diatomite content. This finding may result in improved stratigraphic correlations of the more laterally continuous diatomaceous mudstones based on PNC logs. The PNC log data from the field trial, when used in conjunction with core, temperature, and pressure data, were critical in developing a better understanding of foam generation and propagation in the reservoir. Furthermore, they minimized the time and cost required to complete the field trial successfully. They also led to opportunities for vertical expansion of steamflooding in the area.

Vibration Analysis of Thin Cylindrical Containers

The dynamic behavior of cylindrical tanks in the empty or water-filled condition is analyzed. The equation of free vibration is derived for tanks fixed at the base and free at the top by using Lagrange’s equation in which the various energy expressions are worked out on the basis of assumed beam-type functions for the displacements of the shell. Equations are finally derived for natural time periods, mode shapes, and the virtual mass factor of water which may be used for obtaining the response of the tank to superimposed dynamic forces. The effects of length-radius ratio and varying water depth on the natural frequencies are studied by numerical examples.