Small-scale Model Research Articles

Residual Biomass Recovery in the Wine Sector: Creation of Value Chains for Vine Pruning

Waste management is a current and transversal problem in all production areas, including agriculture. Within this economic activity, wine production generates a large amount of waste, namely, that resulting from the winemaking activity itself, such as pomace and grape stalks, and waste resulting from the management of the vineyards, with operations such as vine pruning. The management of vine pruning residuals has traditionally been conducted by burning leftovers on-site, without any use for the energy produced. This research analyzed the potential for the valorization of residual biomass resulting from vine pruning by creating a business model based on value chains of local scale. For this analysis, several samples of residues resulting from the “Loureiro” vine variety planted in Ponte de Lima (northern Portugal) were collected and characterized. The objective of the small-scale business model created, in addition, to solving the environmental problems related to the disposal of waste from agricultural activities, a value chain can be established, contributing to increasing the income of the farmers while introducing a circular bioeconomy and sustainable rural development practices.

Optimized Pilot Point Emplacement Based Groundwater Flow Calibration Method for Heterogeneous Small-Scale Area

Groundwater flow modeling in a small-scale area requires practical techniques to obtain high accuracy results. The effectiveness of the model calibration is the most challenging for simulating the hydraulic head. In pursuit of this, we proposed an optimized groundwater flow calibration method based on the pilot point emplacement technique for a 3D small-scale area in this work. Subsequently, two emplacement structures were tested during the experimentation, the regular pilot point placement, and the middle head measurement down gradient (MHMDG) placement with two different densities. The parameter estimation (PEST) numerical code applying the kriging interpolation was used to estimate the hydraulic conductivity field by MODFLOW. Moreover, geological SGrid models were chosen for the conceptual model. Thirty-seven observation wells were used for experimental simulations to test the proposed method in a heterogeneous confined aquifer. The result shows that the small-scale modeling was complicated, and the studying area presented a significant heterogeneity in horizontal hydraulic conductivity. The middle head measurement down gradient (MHMDG) pilot point case with the larger density gave the best R-squared 0.901 and minimum residual error of 0.0053 m compared to 0.880 and 0.078 m, respectively, for the regular placement. The calibration accuracy depended on the frequency and the emplacement of the pilot point. Therefore, the initial value should be technically selected to minimize the computation burden. The proposed techniques help to improve the groundwater flow model calibration based on the pilot point methodology for groundwater resources management.

Numerical Case Studies about Two-Dimensional CHS Joints with Symmetrical Full-Overlapped Top-Connection.

Steel joints made out of circular hollow section profiles are used for many fields of applications, such as wide-span or representative halls for airports. By connecting two inclined pipes to a vertical third pipe, a ramified vertical column is created, where the node is the weakest point in the structure due to the geometrical heterogeneity. The current standards and Design Codes have limitations regarding the geometrical properties of hollow sections joints. However, the kind of steel joint presented in this paper is excluded in the current standards. This paper is about numerical FEA case studies of two-dimensional, circular hollow-section joints to figure out the resistance of atypical steel joints. In the first step, a small-scale model is generated to analyze the influence of the inclination. In the second step, the geometries of the different pipes are extended. The influence of the inclination angle and the stability of the joint are analyzed. It was discovered that the inclination angle between the three pipes has a large influence on the stresses and deflections at the node. By increasing the inclination angle, the maximum applied force can be increased. The extended members change the behavior and the stress distribution.

Development of sustainable prefabricated housing system by small-scale experimental model

Utilisation of unused industrial wastes and the need for rapid volumetric construction led to the evolution of sustainable prefabricated housing elements, particularly for urban slums. An agro-industrial by-product as raw material and waste expanded polystyrene beads as the insulation material are chosen to develop a lightweight prefabricated construction element. This bio-ash is used as a partial replacement, 20 and 10%, for fine aggregates to prepare concrete and a lightweight mix, respectively. A small-scale model of one-third scale is conceptualised according to standards. This model includes precast columns and beams as framed structure and prefab panels as walling and roofing elements. These elements are developed according to the desired mix proportions of the identified raw materials. The respective laboratory specimens are evaluated for physico-mechanical, durability and thermal properties. The developed walling end product is found to be 27% lighter, 8% stronger, 24% less water absorbent and 62% less conductive when compared with the properties of commercially available fly-ash brick. A solar photovoltaic panel embedded into the pitch roof of the model can provide 71% of its generated energy to necessary electrical appliances. The material properties are found to be satisfactory for its on-site application. Also, the model’s erection is 20% faster than the conventional method.

Inference of bipolar neutrino flavor oscillations near a core-collapse supernova based on multiple measurements at Earth

Neutrinos in compact-object environments, such as core-collapse supernovae, can experience various kinds of collective effects in flavor space, engendered by neutrino-neutrino interactions. These include "bipolar" collective oscillations, which are exhibited by neutrino ensembles where different flavors dominate at different energies. Considering the importance of neutrinos in the dynamics and nucleosynthesis in these environments, it is desirable to ascertain whether an Earth-based detection could contain signatures of bipolar oscillations that occurred within a supernova envelope. To that end, we continue examining a cost-function formulation of statistical data assimilation (SDA) to infer solutions to a small-scale model of neutrino flavor transformation. SDA is an inference paradigm designed to optimize a model with sparse data. Our model consists of two mono-energetic neutrino beams with different energies emanating from a source and coherently interacting with each other and with a matter background, with time-varying interaction strengths. We attempt to infer flavor transformation histories of these beams using simulated measurements of the flavor content at locations in vacuum (that is, far from the source), which could in principle correspond to earth-based detectors. Within the scope of this small-scale model, we found that: (i) based on such measurements, the SDA procedure is able to infer \textit{whether} bipolar oscillations had occurred within the protoneutron star envelope, and (ii) if the measurements are able to sample the full amplitude of the neutrino oscillations in vacuum, then the amplitude of the prior bipolar oscillations is also well predicted. This result intimates that the inference paradigm can well complement numerical integration codes, via its ability to infer flavor evolution at physically inaccessible locations.

Evaluating Parameters of Bearing Capacity of Ring Footings

Because of its durability, structural ring footings have been used under the maritime structure’s shallow foundations for many years. so, the efficacy and application of shallow foundations ring footings typically are little understood. These footings was tested for the bearing capacity of this research in a laboratory. The impact of ring depth and stiffness on the bearing capacities of ring footing models was studied in this respect. Ring footings design was based on the structural and geometry requirements. it was estimated that using structural rings would increase the support capacities of both soil-rings and soil-footing depth by 1.62 times. The behavior of a ring footing resting on (sand, clay, sand over clay, clay over sand) soil exposed to vertical stresses was investigated in laboratory experiments. A small-scale physical model was built and tested to achieve this goal. included an aluminum circular footing with a diameter of 100 mm and a d/D ratio of (0,0.33,0.5,0.67,0.95) to see how the d/D ratio affected bearing capacity along with different embedding depths to observe how they affect depth and footing size affected bearing capacity. Because the number of drilling and filling operations decreases as it varies from conventional foundations in that it has an increasing number of ring footings. By using the peripheral ring, it is possible to avoid excavating in adjacent construction sites subsurface soil, which reduces the amount of disturbance. This structure appears critical for expense and productivity given the potential advantages of using rings as feet. Meanwhile, further research into the adjacent foundations' bearing capacity and settling activities is needed to show their advantages to practical engineers

AI based Early Flood Warning System

Abstract: Community Based Early Flood Warning System". Which covers study of early warning system in India, Study of 1OT based software and hardware, to build small scale working model on IOT based Interface. Due to use of such technology impacted community will be brought into the network of disaster relief committee, local media, local, police, the military unit and flood monitoring and forecasting station of the department of Hydraulic and Metrology. This technology will be proved very effective and will give warning and response immediately during the time of flood. This paper also gives a brief idea about the work done for the preparation for small scale model and various kinds of IOT based hardware, software and components used in it. Keywords: IOT based sensors, Arduino uno R3, early flood warning, Bluetooth module

Creation Skills of Perspective Effect Drawing of Garden Landscape Based on CAD Technology

In order to enable more garden landscape design enthusiasts to master the creation skills of perspective renderings, this article introduces CAD computer-aided technology in the creation process of perspective renderings of garden landscapes. In the research, through case analysis, the CAD technology is compared with the commonly used sketch master SketchUp, and the detailed steps of making the garden landscape perspective renderings for small-scale modeling of garden landscapes are compared in detail. Finally, an example analysis shows that the application of CAD technology to the creation of perspective renderings of garden landscape can make the creation process more scientific, reasonable, and more ornamental.

ESTIMATION OF SOFTWARE COMPLEXITY OF CALCULATION OF AUTOREGRESSION COEFFICIENTS AT DIGITAL SPECTRAL ANALYSIS

The subject of research in the article are algorithms for fast calculation of autoregression coefficients in digital spectral analysis and estimation of the number of arithmetic operations required for their implementation. The aim of the article – comparative analysis of the speed of different algorithms for calculating the coefficients of autoregression as part of the algorithms of spectral analysis, including analysis of the complexity of their microcontroller implementation. Tasks to be solved: selection of spectral analysis methods suitable for diagnostics of technological equipment, analysis of methods for calculating autoregression coefficients and derivation of relations for estimating software complexity of algorithms and calculation of numerical estimates of addition and multiplication for some algorithms, adaptation of developed methods and estimates to microcontrollers. spectrum Applied methods: algorithm theory, Fourier transform, natural series, microcontroller programming. The results obtained: it is shown that spectral estimation methods based on Yul-Walker equations, which require the calculation of autoaggression coefficients, combine sufficient resolution and resistance to interference with acceptable implementation complexity. Estimates of the number of additions and multiplications for the Levinson, Durbin, and Trench algorithms are obtained, and their comparative analysis is performed. The calculation times for microcontroller arithmetic with fixed and floating points were count upon. Conclusions: When constructing spectrum analyzers for the diagnosis of technological equipment, it is advisable to use the Yul-Walker method. A comparison of Levinson, Durbin, and Trench algorithms for calculating autoregression coefficients showed that the Trench method requires a minimum number of additions, and the Durbin method requires a minimum number of multiplications. At microcontroller realization of spectrum analyzers, it is necessary to consider features of the arithmetic used by the controller. The Trench method is the fastest in the case of floating-point arithmetic and small-scale modeling. In other cases, Durbin's method is more effective.

Active Absorption of Random Waves in Wave Flume Using Artificial Neural Networks

Abstract A wave flume is primarily intended to reproduce actual sea conditions in order to provide a reliable means of testing for small-scale models. The realization of scaled tests is extremely important for the validation of a project on real scale, since, through the laws of similitude, such tests make it possible to predict the behavior of structures in the ocean as well as their performance during operation. This research aims to develop, test, and validate an active control algorithm for wave absorption in a two-dimensional wave channel—that is, when the waves propagate in only one direction—based on artificial neural networks (ANN). The ANN control algorithm relies on the linear wave theory and the principle of time-reversal of wave propagation; i.e., the phenomenon of wave absorption corresponds to the wave generation when observed in the reverse direction of time. Through this principle, data from wave generation experiments, after proper manipulation, are used to train an ANN capable of generating the control signal used to move the wave-generator device, this time as a wave absorber

Small-Scale Wetland Model for Synthetic Sewage Treatment

With the demand for electricity growing, the migration to renewable sources is a reality. In distributed generation, photovoltaic systems are a renewable and sustainable alternative to the main energy sources to generate electricity. Monitoring a photovoltaic system over its operating time guarantees its good performance. This requires solar radiation and temperature data measured at the installation site or the use of solarimetric stations databases. However, the differences between the results simulated with databases and with data measured at the installation site are not widely known, which would be the ideal case from a technical point of view. The aim of this study was to verify the feasibility of monitoring the performance of a 2.5 kWp photovoltaic system located in the city of Porto Alegre - Brazil using the System Advisor Model (SAM) modeling tool and a public database. Simulation results were compared using data provided by a station of the National Institute of Meteorology (INMET) with the results obtained with data measured at the site of the photovoltaic system. Differences were verified between the solar radiation measured on site and that of the INMET database, and the difference in accumulated radiation was 9.2% for the entire period analyzed. When comparing the measured and simulated alternating current energy using the radiation and temperature data measured on site for the non-shading time, it was found that the difference between the results was 0.5%. Using the INMET climate file, the monthly differences ranged from -6% to 14% and the difference in accumulated energy for the entire measurement period was 2.5%. The results showed that the use of a database measured by a public solarimetric station close to the site, in this case approximately 6 km away from the installation, is feasible for monitoring photovoltaic systems, since the differences found were not significant. This monitoring can identify system failures and performance loss over time.

Effect of multiple keyway notches on the fracture behaviour of unirradiated Gilsocarbon graphite I: Small-scale sample sizes and FE modelling

Four-point bend (4PB) samples with seven notch configurations and three-point bend (3PB) samples with four notch configurations have been designed and tested in this study to evaluate the fracture behaviour of virgin Gilsocarbon graphite with simulated keyway notches. The effective stress concentration factor for Gilsocarbon graphite with simulated keyway profile notches was estimated to be around 1.2, which was much smaller compared with the FE modelled theoretical stress concentration factor of ∼ 3.4. In most times, failure occurred at the corner which was under the maximum applied principal stress. However, the large variability in the strength of Gilsocarbon graphite may result in crack initiation location not associated with a largest stress intensification, such as the flat regions of the keyway notches and the notch corners that are not under the maximum applied stress.The number of notches within the sample, combinations of notches, notch distance ratios and a distance between the edges of neighbouring notches were found to have little effect on the nominal net-section fracture strength (nominal strength) of 4PB samples (∼22 MPa). While, the smaller distance between the edges of neighbouring notches (Ln ∼ 8 mm) in 3PB sample configurations T1 and T3 resulted in a shielding effect at the inner notch corners, which in turn resulted in a slightly larger nominal strength at T1 and T3 configurations (∼24 MPa) than that of T2 and T4 configurations (∼22 MPa) where little shielding effect was observed (Ln ∼ 13 mm).

Effect of Farmland Scale on Farmers' Application Behavior with Organic Fertilizer.

The application of organic fertilizer is an important measure for improving the quality of agricultural products and realizing the sustainable development of agriculture. The original small-scale family business model in China is no longer suitable for the development of modern agriculture. Large-scale agricultural business has become the mainstream trend, accompanied by the increasingly active land-transfer market. It is, therefore, necessary to determine whether farmland scale influences farmers’ organic fertilizer applications in China. Based on the analysis of the influence mechanism of farmland scale on farmers’ organic fertilizer application behaviors, empirical tests were conducted using survey data from 812 citrus farmers in Sichuan Province, China. The results show that the large-scale farmers are more likely to apply organic fertilizer and increase the application intensity than small-scale farmers and that the heterogeneity of farmers also affect their organic fertilizer application behavior. The results suggest that the government should encourage farmers to conduct moderate-scale management and promote their application behavior with organic fertilizer by improving awareness, strengthening education and training, and providing financial support.

Seismic Performance of F3D Free-Form Structures Using Small-Scale Shaking Table Tests.

In recent years, studies that can maximize irregularity have increased as technological constraints weaken owing to the development of construction technology and the increase in demand for free-form structures. Considering this, free-form structures have been constructed using various materials. Concrete is considered most suitable for realizing an atypical shape because it is highly economical and can be assembled in a free form. However, not many studies have evaluated the structural performance of free-form concrete structures using free-form formwork 3D printer (F3D) technology, a 3D printing technology. Free-form structures must be designed to secure structural stability under both dead and live loads, as well as natural hazards such as wind, snow, and earthquakes. Therefore, in this study, we tested a free-form structure constructed by F3D printing using small-scale models that satisfy the similitude law with shaking tables. Furthermore, a finite element analysis was conducted to validate the small-scale tests. Lastly, the seismic performance of free-form concrete structures was evaluated based on the test and analysis results.

Evaluation of the piezoelectric and mechanical behaviors of asphalt pavements embedded with a piezoelectric energy harvester based on multiscale finite element simulations

The piezoelectric energy harvester (PEH) has gained interest for its abilities in harnessing the wasted mechanical energies in pavement. To comprehensively evaluate the piezoelectric effectiveness of PEH under various loading and boundary conditions and further to provide necessary background for future PEH designs, numerical models of tire-pavement-PEH system were developed based on the finite element approaches. The small-scale model of the PEH was established and embedded into a large-scale pavement model to investigate its mechanical and behaviour. In addition, a duplication of the PEH model was built to simulate the piezoelectric behaviour. By transferring the deformations, the large-scale pavement model and the small-scale PEH were effectively coupled. Therefore, both the piezoelectric performance of the PEH and the mechanical responses of the entire system were able to be clearly illustrated. The simulation took into account various temperatures, buried depths, horizontal locations, load values, and traffic speeds. The results indicate that a buried depth of 2 cm can achieve the highest efficiency of energy harvesting; meanwhile, the stress concentration in asphalt layer over the PEH becomes remarkable. The horizontal offsets of the tire loading locations would induce damage in asphalt layer adjacent to the PEH. Heavier loads improve the piezoelectric performance of the PEH to a certain extent, and such improvements are related to the internal structures of the PEH. However, the increase of the load greatly induced the stress concentration behaviour surround the PEH.

A study of sediment erosion of runner seal of a Francis turbine

Abstract Suspended sediment particles included in working fluid of hydro turbines often cause erosion and reduce reliability and lifetime of the hydro turbine. It is important for understanding and suppressing erosion problems to understand characteristics of two-phase-flows of liquid and solid particles. In the present study, experimental and numerical studies were carried out to understand mechanisms of erosion in runner seal of a Francis turbine. The experiments were carried out using small-scale seal models. Flow patterns were visualized using coated mica flakes to understand entire flow patterns and a particle image velocimetry were also carried out to measure velocity field in a meridional cross-section. Accelerated erosion tests were also carried out and it was observed similar erosion distributions to that was observed in the actual hydro-turbine. Numerical flow simulations were also carried out to examine mechanisms of the erosion, contributions of each forces acting on the particles and appropriate parameters to capture characteristics of liquid-solid flows and erosion distribution, which were observed in experiments.

Preliminary flow measurements of a small-scale, vertical axis wind turbine for the analysis of blockage influence in wind tunnels

Abstract The development of competitive lift vertical axis wind turbines (VAWTs) is yet a challenge in wind power research. New designs typically require wind tunnel testing before in site implementation. One of the major problems at the laboratory stage is the appearance of a significant flow blockage for small scale models, which affects the performance of the tested wind turbines and prevents the direct extrapolation of results to open field conditions without previous correction. Unfortunately, a suitable blockage correction for lift VAWTs has not been achieved yet, so more studies are needed in this research field to fill the gap. As part of preliminary work with this aim, a small scale VAWT prototype has been designed, constructed, and tested in a 1.15×1 m2 test section wind tunnel with a semi-closed chamber, featuring a blockage ratio of 0.37. Preliminary aerodynamic measurements were performed for different tip speed ratios on the downstream near wake using a special 3-hole pressure probe. Results show that the wake velocity profiles present a velocity increase around the prototype with a low velocity region in the windward quadrant of the turbine, indicating an important influence of the tunnel boundaries. These preliminary measurements have given an initial insight on the aerodynamic relationships between turbine performance and flow patterns. Additionally, they will help to devise an appropriate strategy for the following experiments, with the final objective of developing a blockage correction for small scaled VAWTs.

Data-driven method to learning personalized individual semantics to support linguistic multi-attribute decision making

In parallel with the development of information and network technology, large amounts of data are being generated by the Internet, and data-driven methodologies are now often being used in decision-making. Recent studies have investigated personalized individual semantics (PIS) in various decision-making contexts to model a fact that words mean different things to different people. However, few studies have investigated PIS in the context of multi-attribute decision-making (MADM). In MADM, in addition to multi-attribute linguistic information, pre-existing classification of the alternatives is always present, which have not been considered in prior research. Most previous studies have simply demonstrated the feasibility of PIS methods with numerical examples using small-scale models, and not with realistic datasets. Therefore, in this study, we propose a data-driven learning model to analyze the PIS of decision makers to support a multi-attribute decision-making model that considers pre-existing classification of the alternatives. Specifically, we first propose a PIS multi-attribute learning function to define a general computation form for comprehensive evaluation of the value of alternatives. Then, considering this pre-existing classification of the alternatives, a PIS learning model is constructed by analyzing the relations between calculated values of alternatives and corresponding class assignments to obtain personalized numerical scales of linguistic terms for a decision maker. Finally, we present a case study based on two datasets and a comparison with other methods to justify the feasibility of the proposed model.

Sustainable light-driven water pump using Büttiker–Landauer ratchet

40% of the world's population faces a serious water shortage. To open the way for this problem, we here propose a light-driven water pump using a Büttiker–Landauer ratchet and examine the performance. Specifically, by using a small-scale model of a channel hydraulic radius of ∼3 mm, we demonstrate that the light-driven water pump having light-absorbing and reflecting parts produces a net flow of ∼0.27 mm/s (flow rate ∼10 μl/s) in a circular channel under the irradiation intensity of 160 W/m2. That is, we have developed a light-driven water pump that works under sunlight without a special energy supply. Furthermore, through the discussion about the scale-up model, we estimate that a 10-times larger-size light-driven water pump has the performance of flow rate ∼1 l/s with a high-pressure difference in the future. Therefore, our technology can help to achieve sustainable transport of water or fluids.

Studies on the behaviour of a passive containment cooling system for the Indian Advanced Heavy Water Reactor

Abstract A passive containment cooling system has been proposed for the advanced heavy water reactor being designed in India. This is to provide long term cooling for the reactor containment following a loss of coolant accident. The system removes energy released into the containment through immersed condensers kept in a pool of water. An important aspect of immersed condenser’s working is the potential degradation of immersed condenser’s performance due to the presence of noncondensable gases. An experimental programme to investigate the passive containment cooling system behaviour and performance has been undertaken in a phased manner. In the first phase, system response tests were conducted on a small scale model to under­stand the phenomena involved. Tests were conducted with constant energy input rate and with varying energy input rate simulating decay heat. With constant energy input rate, pressures in volume V1 and V2 reached almost steady value. With varying energy input rate V1 pressure dropped below the pressure in V2. The system could efficiently purge air from V1 to V2. The paper deals with the details of the tests conducted and the results obtained.