Maximum Intensity Value Research Articles

УМОВИ ФОРМУВАННЯ ПОВЕРХНЕВОГО СТОКУ В МЕЖАХ УРБАНІЗОВАНИХ ТЕРИТОРІЙ ПРИ ВИПАДАННІ ДУЖЕ СИЛЬНИХ ТА НЕБЕЗПЕЧНИХ ОПАДІВ

The research investigates atmospheric precipitation, which according to Ukrainian national regulation has reached the criteria of heavy (≥ 50 mm at ≤ 12 hours) and dangerous (15 – 49 mm at ≤ 12 hours). A total of 98 cases of heavy precipitation (2005 – 2018), and 14 cases of dangerous precipitation (2017 – 2018) were analyzed. The research focuses on the formation conditions and volumes of surface runoff that forms on various types of underlying surface. To obtain a statistically valid classification, a cluster analysis of heavy and dangerous precipitation was carried out. The analysis allowed to distinguish three blocks or clusters, one of which corresponds to the type “mix” of heavy and slight precipitations during the development of frontal stratus clouds with so-called “submerged or flooded” convection, the second cluster corresponds to the type “heavy precipitations”, the third cluster is similar to the first cluster, but is marked by a decrease in the intensity of processes. The degree of connection between the intensity of heavy precipitation and the height of the clouds top was investigated. As a result, it was found that there is an inverse relation between the values. The physical features of the processes of cloud and precipitation formation was considered. The exceptional role of convective clouds in individual frontal massifs and also in the form of “submerged or flooded convection” in the massifs of stratus clouds in the formation of significant volumes of rainwater on the underlying surface was noted. The structure of the temporal changes in precipitation intensity was established: the maximum intensity values, the time of their occurrence, the availability and number of amplification waves and their temporal parameters. On the basis of the obtained indicators, the quantity of the surface runoff for determined processes and for amplification periods were calculated. As a result, it was found that the surface runoff, which formed in the built-up areas, exceeds the surface runoff from the moderately built-up area with almost no artificial pavement by 100 – 300 %.

Strength of Shell Structure Operating in Hydrogenous Media under Pressure

Estimation of strength and durability of any structure can be carried out after finding components of stress-strain state of all its parts. The present work shows that in order to calculate stresses in a certain element of a structure that works under thermo-mechanical loading and contacts hydrogenous media, one should trace distribution of heat and hydrogen concentration in this element. Based on the results obtained when having solved thermo-diffusion problem of heat and hydrogen distribution in a casing of a diffusion apparatus, its stress state was found. Casing of the diffusion apparatus is represented in a shape of a shell of revolution. It was determined that in a thin shell, homogenous fields of temperature and hydrogen concentration are being set for a period that is significantly less than the design operating life of the apparatus. To solve the problem of stress distribution in a shell, S.K. Godunov’s method of discrete orthogonalization was used. In the structure that does not have any manifested stress raisers, a critical point with maximum value of shear stress intensity was found. Consistent patterns of change of the intensity in the critical point were found under the emergency pressure boost in the apparatus at various hydrogen densities. The paper shows that emergency pressure boost in a shell may cause the appearance of zones of plastic yield; when this boost is accompanied by increase in hydrogen concentration, the fracture pattern changes from viscous to brittle.

ДИНАМІКА РІВНЯ ЗАБРУДНЕННЯ УРБАНІЗОВАНИХ ТЕРИТОРІЙ

The article is devoted to the study of changes in the intensity of traffic flows in the street canyons of Kyiv and to determine the dynamics of the intensity of emissions of major pollutants during the day. Due to the rapid growth of the vehicle fleet, there is a significant congestion of the street and road network of cities, which leads to a set of environmental problems. One of the such problems is air pollution with harmful substances. Object of the study: dynamics of pollution of city streets Purpose of the study: study of changes in traffic intensity during the day and assessment of the dynamics of the level pollution of the cities road network. Method of the study: statistical methods, cluster analysis. The change in the level of pollution of city streets during the day depends on dynamic factors, namely the intensity and quality of the traffic flow, meteorological conditions and so on. It is established that the most dangerous intervals of the day will be "peak" periods during which the maximum values of traffic intensity are observed. The article examines the patterns of distribution of traffic intensity during the day and on the basis of determining the environmental performance of real vehicles, technical and operational characteristics of which correspond to the characteristics of "efficient" cars of the corresponding category, determines the daily distribution of emissions of major pollutants. Thus, the obtained results can be used in determining the concentrations of pollutants in the street canyons of cities, which will make operational predictions of the level of air pollution. KEY WORDS: STREET ROAD NETWORK, TRANSPORT FLOWS, TRAFFIC INTENSITY, STREET CANYON, VEHICLE, POLLUTION LEVEL.

Mitigation of Thermal Effects in End Pumping of Nd : YAG and Composite YAG/Nd : YAG Laser Crystas, Modelling and Experiments-=SUP=-1-=/SUP=-

In this work, we have presented a finite element (FE) numerical modelling simulations to study and analyze the thermal effects in Nd : YAG and composite YAG/Nd : YAG laser rods. We have calculated the temperature distributions, stress intensity and thermal focal lengths at different pump powers for both rods. The FE simulations showed that using composite laser rod of undoped cap reduces the maximum value of stress intensity and thermal focal length by ~35% and ~ 50%, respectively. We have verified the FE calculations experimentally by direct measurement of focal length of thermally induced lens by using Hartmann-Shack wavefront sensor. Good agreement was obtained between FE calculations and experimental measurements. Keywords: Nd : YAG lasers, Thermal lens, Wavefront sensing, solid state lasers.

Thermomechanical behavior of an electrically conductive cylindrical implant under the action of external unstable electromagnetic fields

A physical and mathematical model for determining the thermostressed state of an electrically conductive cylindrical implant under the action of external unstable electromagnetic fields, in particular the impulse with amplitude modulation, is proposed. This model allows predicting the maximum allowable values (according to physiological norms) of temperature and stress intensities in the considered implant depending on the parameters of external unstable electromagnetic fields and the time of their action.

Thermomechanical behavior of an electrically conductive cylindrical implant under the action of external unstable electromagnetic fields

A physical and mathematical model for determining the thermostressed state of an electrically conductive cylindrical implant under the action of external unstable electromagnetic fields, in particular the impulse with amplitude modulation, is proposed. This model allows predicting the maximum allowable values (according to physiological norms) of temperature and stress intensities in the considered implant depending on the parameters of external unstable electromagnetic fields and the time of their action.

Effect of Strain Rate on the Microstructure and Texture Evolution of the ZK60 Alloy Sheets

The dynamic recrystallization (DRX), precipitation and texture evolution of the ZK60 alloy sheets rolled at 300 °C with different strain rates were studied, and the effects of texture on the plasticity were also clarified. The DRX grain sizes at five strain rates (5–25 s−1) are 1.4 μm, 1.2 μm, 1.8 μm, 2.4 μm and 2.8 μm, respectively, while the DRX volume fractions are 35.8%, 75.0%, 82.0%, 88.0% and 93.0%, respectively. The maximum intensity values of the (0002) texture are 7.91, 8.22, 7.64, 5.76 and 5.34 at five strain rates, respectively. The strongest (0002) texture is observed at the strain rate of 10 s−1, which is related to the relatively low DRX volume fraction and the precipitation density. The tensile strength (UTS) and yield strength (YS) increases firstly and then decreases, while the elongation (EL) gradually increases with increasing the strain rate, suggesting that the plasticity of the alloy sheet can be improved by decreasing the basal texture intensity and increasing the dispersion degree of the basal texture. The optimal comprehensive mechanical properties are obtained at the strain rate of 10 s−1, with UTS of 358 MPa, YS of 291 MPa and EL of 21.5%. The DRX grain sizes at five strain rates (5–25 s−1) are 1.4 μm, 1.2 μm, 1.8 μm, 2.4 μm and 2.8 μm, respectively, while the DRX volume fractions are 35.8%, 75.0%, 82.0%, 88.0% and 93.0%, respectively. The maximum intensity values of the (0002) texture are 7.91, 8.22, 7.64, 5.76 and 5.34, respectively. The tensile strength (UTS) and yield strength (YS) increases firstly and then decreases, while the elongation (EL) gradually increases with increasing the strain rate, and the optimal comprehensive mechanical properties are obtained at 10 s−1, with UTS of 358 MPa, YS of 291 MPa and EL of 21.5%

The Effect of Heavy Metal Pollutants on Bioluminescence Intensity of Luminous Mushrooms (Nenothopanus sp)

In the South Coastal Forest area, West Sumatra, a luminous mushroom with the species Neonothopanus Sp. This research was conducted with the aim of seeing the effect of heavy metals on the bioluminescence reaction of luminous mushrooms. Starting from the effect of heavy metal concentrations on the intensity and inhibition coefficient of luminous mushroom biolumination. From the measurement results, the maximum intensity value of luminous mushrooms is 499.6 au occurring at a wavelength of 505 nm. At a wavelength of 505 nm, visible light is produced in green. The results obtained are in accordance with observations, because the light emitted by the glowing mushroom is green. If the concentration of heavy metals is greater, the intensity of the bioluminescent fungus (Neonothopanus sp) will decrease. The type of heavy metal affects the intensity of the fungus biolumination. The greatest decrease in intensity occurred in copper (Cu) and iron (Fe), zinc (Zn) and lead (Pb). If the heavy metal concentration is greater, the inhibition coefficient will be smaller. The greatest inhibition coefficient due to the presence of heavy metals occurs in copper (Cu) then iron (Fe), zinc (Zn) and the smallest is lead (Pb).

An Empirical Model for Rainfall Maximums Conditioned to Tropospheric Water Vapor Over the Eastern Pacific Ocean

One of the most difficult weather variables to predict is rain, particularly intense rain. The main limitation is the complexity of the fluid dynamic equations used by predictive models with increasing uncertainties over time, especially in the description of brief, local and high intensity precipitation events. Although computational, instrumental and theoretical improvements have been developed for models, it is still a challenge to estimate high intensity rainfall events, especially in terms of determining the maximum rainfall rates and the location of the event. Within this context, this research presents a statistical and relationship analysis of rainfall intensity rates, total precipitable water (TPW), and sea surface temperature (SST) over the ocean. An empirical model to estimate the maximum rainfall rates conditioned to TPW values is developed. The performance of the maximum rainfall rate model is spatially evaluated for a case study. High-resolution TRMM 2A12 satellite data with a resolution of 5.1 km x 5.1 km and 1.67 seconds was used from January 2009 to December 2012, over the Eastern Pacific Nino area in the tropical Pacific Ocean (0-5°S; 90-81°W), comprising 326,092 rain pixels. After applying the model selection methodology, i.e. the Akaike Information Criterion (AIC) and the Bayesian Information Criterion (BIC), an empirical exponential model between the maximum possible rain rates conditioned to TPW was found with R2 = 0.96, indicating that the amount of TPW determines the maximum amount of rain that the atmosphere can precipitate exponentially. Spatially, this model unequivocally locates the rain event, however the rainfall intensity is underestimated in the convective nucleus of the cloud. Thus, these results provide an additional constraint for maximum rain intensity values that should be adopted in dynamic models, improving the quantification of heavy rainfall event intensities and the correct location of these events.

Numerical investigation on stress intensity around Bone-Implant interface by 3-Dimensional FEA and experimental verification by optical technique

The aim of the current study is to examine numerically the stress intensity along bone-implant interface for selected implant systems under occlusal load using finite element analysis (FEA) and confirming the result experimentally by optical technique. To see the biomechanical performance at bone-implant interface the five types of implant systems are chosen for the current study. A three-dimensional (3D) computer aided design (CAD) is prepared using CreO Parametric modeling software. A non-linear contact between implant and surrounding bone is defined to analyze the stress intensity in the cancellous bone under the applied load of 100 N axial directions, 40 N laterals (Bucco-lingual) direction and 100 N oblique at 45 degree to the longitudinal axis of implant. An experimental photoelastic technique (Optical technique) is used to predict the stress intensity in a cancellous bone near the bone-implant interface using Tardy’s method of compensation. A homogeneous blend of Araldite and hardener material is used to prepare a photoelastic block model. The maximum value of stress intensity is noted in Type-I implant system at apical part of implant whereas minimum value was noted in Type-III implant system under lateral and oblique loads. Stress intensity in cancellous bone at the bone interface is found to be more significant to the applied oblique load.

Automatic Diagnosis for Glaucoma Fusing Multi-Feature and Multi-Classifier

Glaucoma is a chronic and irreversible eye disease leading to blindness, and early detection is particularly important for its diagnosis and treatment. To improve the performance of automatic glaucoma diagnosis, a method based on multi-feature and multi-classifier is proposed. Firstly, an average histogram is obtained for each channel and ophthalmic condition, and 6 features are extracted from the average histogram with the average count of pixels and their maximum intensity value. Secondly, the optimal features combination is screened for each classifier with 10-fold cross-validation. Finally, the three optimal classifiers and their optimal features combination are fused with the principle of democratic voting. With the 10-fold cross-validation algorithm, the fusion model was evaluated on Local and HRF dataset, that achieved accuracy of 91.8% and 93.3%, sensitivity of 86.9% and 86.7%, specificity of 96.7% and 100%, AUC of 0.953 and 0.978, time cost of 1.0 s and 3.9 s per image, respectively. Simulation results show that the proposed method is of high accuracy and generality. It can effectively classify the retinal fundus images and provide technical support for the clinical diagnosis of retinal diseases.

An effective framework for 3D shape measurement of specular surface based on the dichromatic reflection model

Fringe projection profilometry based on phase-shift method has been commonly used for three-dimensional measurement. However, measuring the specular surface is always a challenging task since the specular area cannot present original intensity information. This paper presents a novel framework for measuring objects with specular surfaces. Firstly, a set of phase-shifted fringe patterns with maximum intensity value is projected onto the specular surface. Then, the dichromatic reflection model is developed to theoretically decompose an image into specular and diffuse reflection components, which identifies specular pixels more robustly and effectively than judging by saturation only. Secondly, since the location and intensity of specular areas are acquired, the best projection intensity corresponding to the specular areas can be determined by fitting a power function that transforms captured specular reflection components to projected intensities, aiming to minimize specular areas and decrease specular reflection components. It should be stated here that the assumption based on this paper is that the fewer specular reflection components, the fewer measurement errors. Subsequently, the adaptive fringe patterns, which are constructed using the best projection intensity, are reprojected for phase recovery. Thirdly, it is reasonable that there still exist regions where the specular reflection components are too high. For these information-loss areas, the pixel inpainting technique is adopted when extracting the disparity map. Finally, the ultimate result combines adaptive fringe reconstruction with pixel inpainting. The experiment results verify that the proposed measurement framework can effectively and robustly perform three-dimensional reconstruction of various objects with specular surfaces.

Development of a wide-width raster scanning optical system for high-resolution ultraviolet laser direct micro-patterning

We developed F-theta raster scanning optics for high-resolution ultraviolet (UV) beam direct micro-patterning, capable of machining on a 300-mm wide image with a confined beam spot of less than 20 μm, a 13.5% spot size. To achieve the imaging performance with resolution, F-theta optics based on synthetic silica glass were designed using a high-power laser light source with a wavelength of 355 nm. In addition, to improve the difficulty of optical alignment in conventional systems and the scan linearity between the scan angle and exposing position, F-theta scanning optics were designed to contain two lenses with a rotationally asymmetric high-order polynomial surface. The designed optical system showed a performance of 20 ± 2 μm at the full width of a 1/e2 maximum intensity value through a 0.8 mm focal depth. The scanning linearity error and root-mean-square (RMS) wavefront error were designed to be less than 0.2% and 0.05 λ, respectively. The design performance was verified using optical characteristic measurements and actual patterning experiments with the optics composed of proto lenses

Cut, overlap and locate: a deep learning approach for the 3D localization of particles in astigmatic optical setups

Astigmatic optical systems encode the depth location of spherical objects in the defocus blur of their images. This allows the simultaneous imaging of 3D positions of a large number of such objects, which can act as tracer particles in the study of fluid flows. The challenge lies in decoding the depth information, as defocused particle images might be overlapping or have low maximum intensity values. Current methods are not able to simultaneously detect and locate overlapping and low-intensity particle images. In addition, their cost of computation increases with particle image density. We show how semi-synthetic images of defocused particle images with proximate center point positions can be employed to train an end-to-end trainable particle image detector. This allows for the detection of low-intensity and overlapping particle images in a single pass of an image through a neural network. We present a thorough evaluation of the uncertainty of the method for the application of particles in fluid flow measurements. We achieve a similar error in the depth predictions to previous algorithms for non-overlapping particle images. In the case of neighboring particle images, the location error increases with decreasing particle image center distances and peaks when particle image centers share the same location. When dealing with actual measurement images, the location error increases by approximately a factor of two when particle images share the same center point locations. The trained model detects low-intensity particle images close to the visibility limit and covers 91.4% of the depth range of a human annotator. For the employed experimental arrangement, this increased the depth range along which particle images can be detected by 67% over a previously employed thresholding detection method (Franchini et al. in Adv Water Resour 124:1–8, 2019).Graphic abstract

Investigation of turbulence-induced quadrupole source acoustic characteristics of a three-dimensional hydrofoil

In order to investigate the turbulence-induced acoustic characteristics of hydrofoils, the flow and sound field for a model NH-15-18-1 asymmetric hydrofoil were calculated based on the mixed method of large eddy simulation (LES) with Lighthill analogy theory. Unsteady fluid turbulent stress source around the hydrofoil were selected as the inducements of quadrupole sound. The average velocity along the mainstream direction was calculated for different Reynolds numbers [Formula: see text]. Compared to experimental measurements, good agreement was seen over a range of [Formula: see text]. The results showed that the larger the [Formula: see text], the larger the vortex intensity, the shorter the vortex initial shedding position to the leading edge of the hydrofoil, and the higher the vortex shedding frequency [Formula: see text]. The maximum sound pressure level (SPL) of the hydrofoil was located at the trailing edge and wake of the hydrofoil, which coincided with the velocity curl [Formula: see text] distribution of the flow field. The maximum SPL of the sound field was consistent with the location of the vortex shedding. There were quadratic positive correlations between the total sound pressure level (TSPL) and the maximum value of the vortex intensity [Formula: see text] and velocity curl, which verified that shedding and diffusion of vortices are the fundamental cause of the generation of the quadrupole source noise.

Variaciones de las vocalizaciones del bebé y del habla materna en función de la depresión posparto: Modulaciones según edad y sexo infantil

El presente trabajo indaga sobre la influencia de la depresion posparto (DPP) materna en las caracteristicas prosodicas del Habla Dirigida al Bebe (HDB) y las emisiones preverbales infantiles en diversos contextos de interaccion madre-hijo/a. Participaron 40 madres y sus bebes entre 3 y 6 meses de edad. Las madres fueron evaluadas con la Escala de DPP de Edimburgo (Cox, Holden y Sagoysky, 1987) y las diadas madre-hijo fueron filmadas en sesiones de juego no estructurado; 27 madres no presentaron indicadores de DPP y 13, si. Las madres con DPP emitieron menor cantidad de vocalizaciones que las del grupo control y presentaron menor intensidad media y maxima al hablarle a sus bebes de 5-6 meses y esto fue particularmente observable en bebes varones (p < .07). Ademas, estas madres usaron menos curvas descendentes al dirigirse a bebes mas pequenos (3-4 meses) y curvas ascendentes y descendentes al dirigirse a sus hijos varones (p < .01). En los bebes –tanto en los de 5-6 meses como en varones– (con madres con DPP se observo menor produccion de emisiones preverbales, aunque sin ser significativa. La DPP materna impacto en los bebes mas pequenos observandose una disminucion de la frecuencia fundamental (p < .01) y de las intensidades media y maxima, pero solo en bebes varones (p < .05). Tambien se hallo una ausencia de curvas con forma de U en los varones e hijos de madres con DPP (p < .05). Aparentemente, la DPP afecta el HDB materno, el que varia a nivel acustico y prosodico en funcion de la edad del bebe afectando las emisiones preverbales, siendo mayor el impacto en los varones.

Spatial extreme modeling using student t copula approach in Ngawi Regency

Extreme rainfall is an unpredictable phenomenon which causes suffering effect such as flooding. Located on the Equator area, Indonesia results in a high intensity of extreme rainfall. Initial information regarding the patterns, characteristics, and rainfall prediction is needed in order to minimize the negative effect of such phenomenon. A method that can be used to predict extreme rainfall is the spatial extreme value using the copula approach. The copula approach used in this study is student-t copula. The Generalized Extreme Value (GEV) distribution used for the student-t copula with parameter estimation is Pseudo-Maximum Likelihood Estimation (PMLE). The proposed method was applied to model the extreme rainfall atNgawi Regency. An extreme spatial dependency on location is shown by extreme coefficient graphic. The best model that is obtained is based on Akaike Information Criteriation’s (AIC) lowest value. The best model then continues to be used to predict the rainfall intensity return level. The prediction result of the rainfall intensity return level value shows that the maximum value of rainfall intensity increases from year to year in each station.

Ensuring the Environmental Safety of Coal-fired Power Plants for the Flue Gases Purification

The article is devoted to solving of the pressing issue–provision of ecological safety of urban areas in flue gas purification of coal power plants and boiler houses. Use of the method for evaluating and selecting the maximum ecological efficiency and energy intensity value of purification of exhaust gases of thermal power plants and boiler houses of municipal services within the known physical and energetic approach allowed to obtain the parametric dependence of ecological efficiency and energy intensity value and determine the optimum parameters of hydrodynamic cleaning process with further designing of a new technical solution.On the basis of the simulation process and cleaning systems a new device of hydrodynamical (wet) cleaning the flue gases via control parameters significantly affecting the ecological efficiency and energy intensity value of the cleaning process was worked out. Moreover, control of parameters is carried out at the design of flue gases cleaning system, which allows to significantly optimize the choice of ways and means of reducing air pollution in urban territories. The obtained simulation results can be used to develop new or improve existing devices of hydrodynamic flue gases purification.

Optical diagnostics on the effects of fuel properties and coolant temperatures on combustion characteristic and flame development progress from HCCI to CDC via PPC

The effects of fuel properties and coolant temperatures on combustion characteristic and flame development progress were investigated in an optical engine. The combustion mode was transited from homogeneous charge compression ignition (HCCI) to conventional diesel combustion (CDC) via partially premixed combustion (PPC) by changing the start of injection (SOI) timings from early to late injections. The main fuel properties were separated by using diesel, n-heptane, iso-octane, n-butanol and their mixtures. Diagnostics included conventional in-cylinder pressure and heat-release analysis, high-speed imaging and the spatially integrated flame luminosity intensity. The results show that the variation of combustion phasing (CA50) is more sensitive to the variation of fuel properties of cetane number, latent heat and atomic oxygen at all tested combustion modes. However, fuel physical properties such as dilution, viscosity and volatility only have significant effects at HCCI, while minor effects at PPC and CDC. Fuel properties have minor effects on flame development progress, but significant effects on maximum value of natural flame luminosity intensity. At SOI-15, the main factor to reduce the maximum value of natural flame luminosity intensity is the dilution, viscosity and volatility (40%) followed by the latent heat and the atomic oxygen (18.5%) and cetane number (1.6%). At SOI-5, the main factor is the cetane number (44.1%) followed by the latent heat and the atomic oxygen (36.2%) and dilution, viscosity and volatility (2.4%). Coolant temperature significantly influences combustion phasing and peak in-cylinder pressure and heat release rate at early injection timings, but these effects weaken at late injection timings.

Analysis of stresses and deformations of elements of axle boxes and improvement of their shape

The development of constructive recommendations aimed at increasing the service life of roller bearings of axle boxes of railway cars is described. The elastic volumetric stress-strain state of the bearing elements of the bearings under consideration is analyzed. Numerical analysis of the corresponding mathematical models was carried out using the finite element method in the NX NASTRAN software environment. It is shown that near the edge of the roller with chamfer-rounding, a stress concentration arises, caused by insufficient smoothness of the contour line of the axial section of the roller. It is noted that this concentration is caused by the fact that the line of the contour under consideration has a finite specified curvature in the section corresponding to the chamfer and almost zero curvature in the adjacent straight section corresponding to the cylindrical surface of the roller. It is shown that the use of smoother contour lines for the marginal zone of a roller more than doubles the maximum value of the stress intensity in the boundary zone under consideration and accordingly increases the cyclic life of the bearing. The proposed smoothing of the line of the considered circuit allows one not only to unload the edge of the roller but also to reduce the contact pressure in its middle part. At the same time the stress-strain state of the roller becomes more uniform by increasing the smoothness of the contour line in the area of the roller’s edge and simultaneously reducing the degree of bombing (barrel-shaped) its cylindrical surface.