Real Characteristics Research Articles

TEORETICAL-EXPERIMENTAL COMPARISON OF THE MODELS OF ADDITIVELY MANUFACTURED SWIRL INJECTORS BASED ON THE HYDRAULIC TESTING RESULTS

Annotation. Recent success in development of the technology stipulated the appearance of advanced additive manufacturing aimed to shift conventional subtractive manufacturing from its position in the engineering field. Thus, for LPRE manufacturing there is an obvious advantage of additive manufacturing in terms of ability to produce single-piece parts with complex geometry must be seriously considered. In the modern world there is a constant competition between complex engineering decisions and cost efficiency of the production on the market of liquid propellant rocket engines. On the one hand, mixing head is one of the most demanding parts of LPRE in terms of designing. On the other hand, the earliest stage of its development starts with the choice of a type of mixing elements to ensure combustion stability, efficiency, and overall production cost [1]. Typically this step requires advanced knowledge in the real characteristics of produced injectors, or extensive experimental study should be carried out otherwise. In this work a problem of determining the characteristics of additively manufactured swirl injectors is considered. Laser Powder Bed Fusion [10] was chosen as a production method using Haynes 230 as a main material. A range of the swirl injectors with varied geometrical parameters was manufactured. Hydraulic testing was carried out in a wide range of Reynolds numbers for determining flow characteristics. Typically, discharge coefficient and spray angle are the desired values to know. Sauter mean diameter and film thickness were not studied due to lack of equipment. Considering a problem of prediction of the main characteristics of the produced injectors, a review on known equations for calculation of the main parameters was performed. Comparative analysis between calculated and experimental data was carried out. Results show that there is severe discrepancy between calculated values of characteristics of injectors and experimentally obtained data for additively manufactured swirl injectors. Even though the conducted study gives a base to form consistent conclusions of the behavior of the obtained characteristics, additional investigation is required.

Dynamic Parameters Updating of Earth-rock Dams Based on Modal Parameter Identification

Dynamic Parameters Updating of Earth-rock Dams Based on Modal Parameter Identification

Real world emission characteristics of Chinese fleet and the current situation of underestimated ship emissions

Real world emission characteristics of Chinese fleet and the current situation of underestimated ship emissions

Incorporating Wetland Delineation and Impacts in Watershed-Scale Hydrologic Modeling

In semi-distributed hydrologic models, it is difficult to account for the impacts of wetlands on hydrologic processes, as they are based on lumped, subbasin-scale wetland concepts. It is a challenge to incorporate the influences of individual small wetlands into watershed-scale models by using lumped parameterization. The objective of this study was to improve watershed-scale hydrologic modeling by taking into account real wetland features during the wetland parameterization. To achieve this objective, a joint modeling framework was proposed to couple a surface delineation algorithm with a semi-distributed hydrologic model and then applied to the Upper Turtle River watershed in North Dakota, USA. The delineation algorithm identified the topographic properties of wetlands, which were further utilized for wetland parameterization. A nonlinear area–storage relationship was determined and used in the estimation of the wetland-related parameters. The results demonstrated that the new joint modeling approach effectively avoided misestimating the wetland-related parameters by accounting for real topographic characteristics (e.g., storage, ponding area, and contributing area) of identified wetlands and their influences, and provided improved modeling of the hydrologic processes in such a wetland-dominated watershed.

Development of models of current relays and power direction relays in the MATLAB software

During pandemics and military aggressions, the continuation of education is ensured by the active implementation of distance learning technologies. A significant number of real-life processes can be described using mathematical models. Their further implementation in the program code and the finished software product allows them to be effectively used in virtual studies of relay protection schemes. For the correct functionality of any virtual relay or protection complex, it is necessary to build a model that takes into account the real characteristics of its constituent elements. In case of absence of the latter, they should be determined empirically. To create a virtual laboratory work on the study of the RT-40 current relay, based on the parameters specified in the passport for this device, an algorithm was created that allows the user to interactively determine the main characteristics of the relay: tripping current, release current, and response time depending on the current through the relay using various circuit elements (sliders, regulators, etc.). The algorithm of the program “Research of characteristics of power direction relay RBM-171” uses the angular characteristics and sensitivity characteristics of the real relay RBM-171, which were converted into digital form. For the RBM-178 relay, which has a different connection scheme and maximum sensitivity angle from the previous test stand, a separate test stand “Study of the RBM-178 power direction relay” was created. The logic of its operation is based on the detection of zero-sequence currents and voltages using the method of symmetrical components. All laboratory circuits have visualization and indication of the states of the circuit elements present on the stands. This allows the user to achieve more accurate results and get closer to testing relays in real laboratory conditions.

New Two-Level Machine Learning Method for Evaluating the Real Characteristics of Objects

A new two-level ensemble regression method, as well as its modifications and application in applied problems, are considered. The key feature of the method is its focus on constructing an ensemble of predictors that approximate the target variable well and, at the same time, consist of algorithms that, if possible, differ from each other in terms of the calculated predictions. The ensemble with the indicated properties at the first stage is constructed through the optimization of a special functional, whose choice is theoretically substantiated in this study. At the second stage, a collective solution is calculated based on the forecasts formed by this ensemble. In addition, some heuristic modifications are described that have a positive effect on the quality of the forecast in applied problems. The effectiveness of the method is confirmed by the results obtained for specific applied problems.

Seismic spatially variant noise suppression method in the Tarim Basin based on FFDNet and transfer learning

Due to a complex geologic structure and ultradeep reservoir location, noise distribution of prestack seismic data in the Tarim Basin is nonuniform. However, most of the current seismic random noise suppression methods lack the flexibility to deal with spatially variant random noise. To address this issue, we have developed an intelligent denoising method for seismic spatially variant random noise and applied it in the Tarim Basin. On the basis of denoising convolutional neural network (DnCNN), we add an extra channel to the input and introduce a tunable noise level map as input. The noise level map has the same dimensions as the input noisy seismic data, and each element in the noise level map corresponds to a denoising level. By adjusting the noise level map, a single model can handle noise with different levels as well as spatially variant noise. Due to the lack of labeled field data in the Tarim Basin, we introduce a transfer learning scheme that transfers features of effective signals learned from synthetic data to the denoiser for field data. The network learns the general and invariant features of an effective signal from a large number of easily obtained synthetic data and then learns the real effective signal characteristics from a small amount of approximately clean field data in the target area by fine-tuning. The processing results of synthetic and field data demonstrate that, compared with f- x deconvolution, dictionary learning, and DnCNN, our method exhibits high effectiveness in suppressing spatially variant random noise and preserves effective signals better.

Improvement and Implementation of Transformative Cultural Education Management Programs

This paper use a mixer methodology is employed, incorporating both a literature review and field studies. The central theme focuses on the management of Education Culture, including its historical development, conceptual framework, and the implementation of transformative iseducation. This paper aims to address three fundamental questions: firstly, what is the concept of Cultural Management in regard to Education? Secondly, what is the history and conception of education management, as well as transformative culture, within the context of Indonesia? Lastly, what contributions does education management make to the transformation of culture within the education sphere in Indonesia. Additionally, this document emphasizes the crucial role of teacher supervision as a definitive process. Moreover, it highlights the integration of culture as an inseparable component of the local community, deeply intertwined with the community's language. Culture (often called local wisdom) will be passed down through generations through oral stories. Education based on truth and nobility, distancing oneself from unreal thoughts, even far from the origins of unpleasant behavior or influence. Leadership education is important for moral (character)/ethics is easy), then the soul (emotional realm) is not only a cognitive and psychomotor realm, but synergizes with culture, education, and tourism, and needs to be developed in a coordinated mannerin education with real regional characteristics.

A Markov Model of Gap Occurrence in Continuous Glucose Monitoring Data for Realistic in Silico Clinical Trials

A Markov Model of Gap Occurrence in Continuous Glucose Monitoring Data for Realistic in Silico Clinical Trials

Interpreting Housing Prices with a MultidisciplinaryApproach Based on Nature-Inspired Algorithms and Quantum Computing

Current technology still does not allow the use of quantum computers for broader and individual uses; however, it is possible to simulate some of its potentialities through quantum computing. Quantum computing can be integrated with nature-inspired algorithms to innovatively analyze the dynamics of the real estate market or any other economic phenomenon. With this main aim, this study implements a multidisciplinary approach based on the integration of quantum computing and genetic algorithms to interpret housing prices. Starting from the principles of quantum programming, the work applies genetic algorithms for the marginal price determination of relevant real estate characteristics for a particular segment of Naples’ real estate market. These marginal prices constitute the quantum program inputs to provide, as results, the purchase probabilities corresponding to each real estate characteristic considered. The other main outcomes of this study consist of a comparison of the optimal quantities for each real estate characteristic as determined by the quantum program and the average amounts of the same characteristics but relative to the real estate data sampled, as well as the weights of the same characteristics obtained with the implementation of genetic algorithms. With respect to the current state of the art, this study is among the first regarding the application of quantum computing to interpretation of selling prices in local real estate markets.

Effects of Support Friction on Mixed-Mode I/II Fracture Behavior of Compacted Clay Using Notched Deep Beam Specimens under Symmetric Fixed Support

This paper investigates the effects of support friction on mixed-mode I/II fracture behavior of compacted clay using notched deep beam (NDB) specimens under symmetric fixed support. Numerical models of 330 NDB specimens were established considering the crack inclination angle, crack length, support span, and support friction coefficient, and the normalized fracture parameters (YI, YII, and T*) of NDB specimens were calibrated. The numerical results showed that the values of YI, YII, and T* decreased at different degrees after considering the support friction. Notably, the support friction coefficient could significantly change the loading pattern at the crack tip. To verify this phenomenon, 12 compacted clay NDB specimens were prepared, and a mixed-mode I/II fracture test was performed under fixed support conditions; the phenomenon of asymmetric crack propagation was studied. The test data were processed using the numerical calibration results of YI, YII, and T* with and without consideration of friction. Afterward, the test data were compared and analyzed by combining the generalized maximum tangential stress (GMTS) and the maximum tangential stress (MTS) criteria. The analysis indicated that the real fracture characteristics of compacted clay NDB specimens could not be reflected when conducting mixed-mode I/II fracture tests under symmetric fixed support conditions if the test results were analyzed by YI, YII, and T* without considering support friction, as in previous studies.

Hybrid phase-field modeling of mesoscopic failure in concrete combined with Fourier-Voronoi stochastic aggregate distribution modelling approach

Hybrid phase-field modeling of mesoscopic failure in concrete combined with Fourier-Voronoi stochastic aggregate distribution modelling approach

Pengembangan dan Implementasi Program Manajemen Pendidikan Budaya Transformatif untuk Sekolah Dasar

This paper uses a mixer methodology, first with literature review and second with field studies, the theme raised is Islamic Education Cultural Management: History, Conception, and Management of Transformative Islamic Education Actualization, in this paper there are three fundamental questions; first, what is the concept of Cultural Management of Islamic Education in Islam. Second, what is the history, conception of Islamic religious education management, Islam, transformative culture in Indonesia and third, what is the contribution of Islamic education management in a transformative Islamic culture in the Islamic education space in Islam in Indonesia. Which is where teacher supervision is a definite process. Furthermore, culture becomes part of the culture of the local community which cannot be separated from the language of the community. Culture (often called local wisdom) will be passed down through generations through oral stories. Islamic religious education based on truth and nobility, distancing oneself from unreal thoughts, even far from the origins of unpleasant behavior or influence. Islamic religious leadership education is important for moral (character)/ethics is easy), then the soul (emotional realm) is not only a cognitive and psychomotor realm, but 4) synergizes with culture, Islamic religious education, and tourism, and needs to be developed in a coordinated mannerin Islamic religious education with real regional characteristics.

METHODS AND MEANS OF DIAGNOSING PUMPS AND HYDRAULIC MOTORS BY EFFICIENCY

To determine the technical condition of the elements of hydraulic drives during exploitation, it is proposed to choose a control method that provides an effective assessment at the lowest cost and allows you to determine those parameters, the change of which during exploitation leads to maximum losses. In addition, the selected parameters should allow to control the technical condition of the hydraulic drive elements without removing them from the machine and without disassembly. These requirements, first of all, corresponds to the control of the technical condition of the hydraulic drive by the coefficient of efficiency. The definition of total losses, hydromechanical losses and volumetric losses is considered. It is shown that it is possible to determine both the total energy efficiency and the hydromechanical efficiency, to estimate the losses by the specified equations, taking into account the effect of compressibility of the working fluid. To determine the real parameters of hydraulic systems and to assess the actual performance of the efficiency, a set of diagnostic tools for hydraulic systems developed by the Department of Hydraulic Machines named after academician G. F. Proskura was used, with which the measured parameters can be recorded on an internal memory card or transmitted via wireless Bluetooth to a personal computer PC or Android device (smartphone, tablet) for further processing. A scheme for testing pumps with open and closed circuits, as well as a scheme for testing hydraulic motors is given. These schemes indicate on which positions this set can be used. The given theoretical dependences, together with the processed data, and obtained with the help of the developed set of diagnostic tools, allow to determine and build the real characteristics of the units, taking into account the power loss, which can vary depending on the pressure level, fluid temperature and the amount of air dissolved in the liquid.

Experimental study of radiating structures with substrates of planar chiral metamaterial based on S-elements and gammadion

At the moment, the actual scientific and technical task is to reduce the weight and size characteristics of the metamaterial, as well as to reduce the technological complexity of manufacturing chiral elements. This article is devoted to experimental studies of radiating structures with substrates of planar chiral metamaterial based on S-elements and gammadions, which make it possible to determine their real characteristics, as well as to verify the results obtained by electrodynamic modeling methods. The obtained results of an experimental study of the characteristics of layouts of planar chiral metamaterials based on S-elements and gammadions indicate the presence of "screen" properties in a number of frequency ranges. At the same time, the "chiral properties" of these planar metamaterials are expressed worse than those of bulk metamaterials based on spirals. These chiral metamaterials can be used in solving problems of electromagnetic compatibility of closely located radio-electronic means.

CO211 Real-World Treatment Patterns of Early-Stage Hepatocellular Carcinoma (HCC) after Complete Resection or Ablative Therapy: Retrospective, Medical Chart Review in the United States

CO211 Real-World Treatment Patterns of Early-Stage Hepatocellular Carcinoma (HCC) after Complete Resection or Ablative Therapy: Retrospective, Medical Chart Review in the United States

Predict the fatigue unloading elastic-plastic reduction mechanism of single crystal 3C-SiC Newton layer by reconstructed multi-dimensional dynamic static combination indenter

Predict the fatigue unloading elastic-plastic reduction mechanism of single crystal 3C-SiC Newton layer by reconstructed multi-dimensional dynamic static combination indenter

Normalized Temperature Drought Index (NTDI) for Soil Moisture Monitoring Using MODIS and Landsat-8 Data

As the fundamental regulator of energy exchange in the vegetation–soil–atmosphere circulation system, soil moisture is a key parameter for drought monitoring and is indispensable to the land surface hydrological processes. In order to overcome the constraints of the Perpendicular Drought Index, PDI (performs poorly over the fields with dense vegetation and hard to construct the soil line), and the Temperature Vegetation Drought Index, TVDI (requires similar atmospheric forcing and large enough dimension of mapping area), in soil moisture monitoring, a new drought index (Normalized Temperature Drought Index, NTDI) is proposed to explore the spatiotemporal changes of soil moisture by substituting red and near-infrared reflectances with vegetation index and normalized land surface temperature on the basis of the PDI framework. Victoria, Australia, was selected as the study area as it experiences many severe droughts and has been affected for more than ten years. Time series of satellite-based data were applied to evaluate the effectiveness and applicability of the NTDI at the regional scale. Results indicated that the expression of the soil line representing the water condition of the bare soil is easier to obtain in the new trapezoid framework and has good fits with the coefficients of determination (R2) of more than 0.8. Compared with PDI, TVDI and Modified PDI (MPDI) at the cropping sites, NTDI exhibits a relatively better performance in soil moisture monitoring for most days where the R2 achieved can reach to more than 0.7 on DOY 242, 254 and 272. Meanwhile, spatial–temporal mappings of the four drought indices from satellite data were conducted, and the NTDI presented the slightly seasonal variation and effectively described the real spatial characteristics of regional drought. Overall, the NTDI seems to a viable approach and can provide insight into spatial and temporal soil moisture monitoring at different scales.

A model for near-perfect transmission through lossy media with acoustic sources

Acoustic metamaterials exhibit effective material properties not found in naturally occurring media, and, as such, have received considerable attention for their potential applications in noise and vibration control, diagnostic imaging, and nonreciprocal transmission. Complementary acoustic metamaterials have been proposed as a means of compensating for the high impedance mismatches of aberrating layers that disrupt the acoustic field and hence distort acoustic images. More recently, a complementary acoustic metamaterial featuring active components was shown in principal to compensate for both the impedance mismatch and energy attenuation of lossy materials, but a physical realization of the concept has not yet been implemented. Here, we present results from a one-dimensional acoustic model showing how a plane wave incident on a lossy material can be augmented by point monopole and dipole sources to allow for near perfect transmission, thus rendering the lossy medium acoustically transparent. We present general expressions for source magnitudes that are dimensionless with respect to frequency, material thickness, and the background medium. We show that these results are consistent with three-dimensional finite element simulations, where the appropriate monopolar and dipolar forces are generated using finite dimensional velocity sources with real loudspeaker characteristics mounted in an acoustic waveguide.

Abbreviations in modern business correspondence and their pedagogical implications

The aim of our contribution is to outline the frequent usage of abbreviation processes in contemporary written business correspondence and to demonstrate the means of creating abbreviations in this specific area of English. In the light of the latest trends of economization of speech in business communication, the abbreviation formation is highly topical and for this reason, we focus on the analysis of the specific content of written business correspondence. For a better understanding of the issue of economization of speech and business correspondence, we define contemporary business communication in more detail, focusing on written correspondence. By using the method of corpus analysis, we qualitatively describe the regularities and irregularities in the creation of abbreviations extracted, which allows us to find out which abbreviation phenomena are a reflection of the real characteristics of the jargon of business correspondence and which are rarely found in it. The outcome of our analysis is also reflected in its pedagogical implications.