Distortion Phenomenon Research Articles

Wage distortion and green technological progress: A directed technological progress perspective

In this paper, we construct a theoretical model considering that wage distortion is exogenous and endogenous, respectively, to explore the effect of wage distortion on green technological progress. Furthermore, using the panel data of China's industrial sector, we investigate the direct influence and mediating effect of wage distortion on green technological progress. We find that the green technological progress of China's industrial sector continued to rise from 2002 to 2012. However, the green technological progress of China's manufacturing sub-sectors is relatively slow. The wage distortion phenomenon that the labor's real wage level is less than the labor's marginal product level is widespread, especially in manufacturing sub-sectors. Moreover, green technological progress has a path-dependence characteristic. Wage distortion plays an important role in the changes in the direction of green technological progress. Green technological progress is more likely to appear in the sub-sectors which experience low wage distortion degree, while the sub-sectors with severe wage distortion experience a lower green technological progress rate. Wage distortion increases industrial profit margins by deliberately suppressing the rise of wages. In addition, increased industrial profit margins reduce the incentives of the green technological innovation of equipment suppliers and inhibit the improvement in green production technology. Therefore, alleviating wage distortion can benefit the green development of industrial sector.

Propagation and Attenuation Characteristics of an Ultrasonic Beam in Dissimilar-Metal Welds.

Ultrasonic inspection of welds joining dissimilar metals in nuclear power plants has proven to be a challenge, because the ultrasonic waves are subject to diffraction, distortion, scattering, and noise. These perturbations are due to their interactions with coarse-grained microstructures having anisotropic and heterogeneous metallurgical properties that can promote ultrasonic attenuation. In this paper, to improve the reliability of ultrasonic testing for dissimilar-metal welds (DMWs), ultrasonic beam characteristics for DMWs with a buttering layer were investigated in order to analyze the beam distortion phenomenon caused by inhomogeneous anisotropic properties and coarse grains. Ultrasonic testing was performed on DMW specimens using single ultrasonic transducers to investigate the behavior of the ultrasonic beam in the welds. According to the anisotropic and heterogeneous properties, when passing through the weld and the buttering layer of the DMW, ultrasonic waves were distorted and attenuation was high. In particular, in the case of using angular incidence that passed through the weld and the buttering layer in turn, the received ultrasonic data did not contain accurate internal information. From this, it was verified that internal defects may be detected by transmitting ultrasonic waves in different directions. Finally, the existing limitations on the application of non-destructive ultrasonic testing to dissimilar-metal welds were verified, and a solution to the measurement method was proposed.

Difficulty and complexity in dealing with visual pollution in historical cities: The historical city of Ibb, Yemen as a case study

The historical cities in the third world suffer from many environmental problems; one of them is the spread of visual pollution manifestations. These phenomena increase with low levels of public awareness and low per capita income. Despite the historical and cultural importance of the Old City of Ibb, the manifestations of visual pollution are increasing day after day. This study aimed at identifying the difficulty and complexity of dealing with visual pollutions manifestations in the historical city of Ibb and to provide appropriate solutions that are suitable for the complex and contradictory circumstances. The study relies on an inductive approach to achieve its aims through two methods; the first is a visual survey of the visual pollution phenomenon, based on images and observations. The second method is the analyses of the opinions and impressions of three parties related and interested in the phenomenon, namely residents and visitors of the city, competent authorities’ officials, and some specialists in the field of the urban environment. The study presents an analysis of the phenomenon of visual distortion of the historical city of Ibb in terms of its appearances and causes. Furthermore, this study provides appropriate solutions, which are suitable for complex and contradictory circumstances. These solutions focused on the methods to stop the spread of visual distortions, and the ways of addressing the current visual pollutions.

Doppler distortion removal based on Dopplerlet transform and re-sampling for wayside fault diagnosis of train bearings

In wayside fault diagnosis of train bearings, the phenomenon of Doppler distortion in the acoustic signal of moving acoustic source acquired with a microphone leads to the difficulty for signal analysis. In this paper, a new method based on Dopplerlet transform and re-sampling is proposed to remove the Doppler distortion, and applied in the fault diagnosis of train bearings. Firstly, search the parameters space to find the primary functions-Dopplerlet atoms. According to the Morse acoustic theory and Doppler effect, the instantaneous frequency of the Dopplerlet atom which we choose to remove Doppler distortion of the corresponding acoustic source can be acquired. Then, the re-sampling sequence can be established as the re-sampling vector in time domain. Through the resample, the Doppler distortion effect can be removed. Finally, simulations and experiments with practical acoustic signals of train bearings with a defect on the outer race and the inner race are carried out, and the results verified the effectiveness of this method. Comparing with the other methods of Doppler distortion removal, this method works without measuring the motion parameters in advance, and is quite robust to noise. Meanwhile, this method has the potential to eliminate the Doppler distortion of original signal with multiple sources.

Modeling Study of EMBr Effects on the Detrimental Dynamic Distortion Phenomenon in a Funnel Thin Slab Mold

The turbulent phenomena occurring in the thin slab mold affect the final product quality. Therefore, it is essential to carry out studies to understand and control their occurrence. Current research aims to study the electromagnetic brake (EMBr) effects on the flow patterns in a funnel thin slab mold. The objective is to prevent the detrimental phenomenon known as dynamic distortions (DD) of the flow, applying the EMBr in the typical horizontal position (H-EMBr) and a new vertical position close to the narrow faces (V-EMBr). The fluid dynamics are simulated using the Reynolds stress model (RSM), the Volume of Fluid (VOF) model and the Maxwell equations in their magnetohydrodynamics (MHD) simplification. The results show that the H-EMBr effectively counteracts the DD phenomenon by reducing the submerged entry nozzle (SEN) ports' mass flow rate differences. The EMBr reduces the highest meniscus fluctuations from −10 to ±3 mm with a field intensity of 0.1T and almost 0 mm for higher field intensities. In contrast, the V-EMBr configuration does not reduce or control at all the DD phenomenon, even though eliminating the upper roll flows does not diminish the meniscus fluctuation amplitudes and induces new small roll flows close to the SEN's wall.

Energy Storage System Control Strategy for Restraining Overvoltage Caused by Switching Non-Load Power Transmission Lines

During the switching operation of the non-load power transmission lines, the undisired switching overvoltage issue is inevitable, causing grid voltage oscillations, waveform distortion and other phenomena at the end of the non-load power transmission lines, and even lead to the insulation breakdown, all above phenomena probably make the power transmission failure. To avoid the above harmful cases, the formation mechanism of the undisired switching overvoltage issue caused by switching non-load power transmission lines is first analyzed in detail. Based on this mechanism analysis, the energy storage system (ESS) based overvoltage suppression method and corresponding ESS voltage command synthesis algorithm are developed. The method can quickly and effectively restrain the voltage change rate and reduce the voltage difference between the initial value and the steady state value of the power transmission lines, so that the line voltage during the switching operation can be kept within the safety limit range. Finally, a simulation model was built by using MATLAB/Simulink software, and the simulation results verified the effectiveness of the proposed overvoltage suppression strategy.

Use of Higher-Harmonic and Intermodulation Generation of Ultrasonic Waves to Detecting Cracks due to Steel Corrosion in Reinforced Cement Mortar

The aim of this work was to provide further confirmation of the possible use of non-linear ultrasonic techniques for detecting the cracking due to corrosion of steel reinforcements in concrete. To this end accelerated steel corrosion tests have been conducted on model reinforced cement mortar specimens, while monitoring the appearance and width evolution of visible surface cracks, and performing non-linear ultrasonic measurements based on the phenomena of harmonic distortion and intermodulation. A new parameter, based on the difference between the amplitude of the fundamental frequency and the sum of the amplitudes of all the first-order and second-order intermodulation products, has been proposed in this work. The results confirm that the appearance of visible surface micro-cracks are preceded and accompanied by the observation of strong non-linear features in the received signal. Furthermore, the new parameter proposed in this work is as efficient as the relative non-linearity parameters, classically used in harmonic distortion non-linear ultrasonic studies, for detecting the non-linear features associated with the critical events of the cracking of cement mortar due to embedded steel corrosion. A hypothesis has been developed considering the possible effect of the filling of the void space by liquid containing rust products after the formation of new cracks or the enlargement of its width. This filling process, which might be particularly enhanced by net convective transport of liquid, would explain the evolution of the values of all the parameters used for putting in evidence the non-linear elastic features after the critical events of the cracking process.

Comparative study of behavior of electrical conductivity in KI‒Al2O3 and KI‒TiO2 heterostructure composites

The present work reports development of binary KI–Al2O3 and KI–TiO2-based nanocomposites using simple solid-state reaction method and is characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy and impedance spectroscopy. The results show the effect of heterogeneously doped Al2O3 and TiO2 on the ionic conductivity of pure KI which is moderately conductive. The results supported the composite development in which the interface layer portrays a significant part in governing the bulk properties of the compound. Improvement in electrical conductivity is seen in the incorporation of Al2O3 and TiO2 dispersoid into the matrix of KI. With temperature, electrical conductivity increased and the activation energies were found to be decreasing. The activation energies for KI–Al2O3 and KI–TiO2 systems were 0.22 eV and 0.21 eV, respectively, in the temperature range 20‒400 °C. Dielectric constant increases with the increase in temperature in the entire temperature range studied attributed to the phenomenon of distortion of electric charges.

Resonant frequency tracking mode on eddy current pulsed thermography non-destructive testing

Eddy current pulsed thermography (ECPT) has been widely used in the field of non-destructive testing due to its safety, non-contact detection, high spatial resolution and intuitive results. Inductive excitation source is an important component of ECPT and provides high-frequency alternating current to drive the excitation coil. However, a resonant frequency distortion phenomenon exists in the excitation source during the detection process, which seriously affects the output power of the excitation source and the sample detection effect. This paper presents a fast resonant frequency tracking loop for full bridge series resonant inverter which is used to search the resonance frequency in real time through direct digital synthesizer (DDS) and all-digital phase-locked loop. Theoretical analysis and simulation are presented to explain the working principle of the loop. Then, an experimental prototype is manufactured which serves as an excitation source for the ECPT experimental system. Compared with traditional excitation sources, the prototype does not need a water-cooled device and the tracking speed can be adjusted by modifying the parameters of DDS. Finally, experiments have been conducted on both artificial slot of 45# steel and natural cracks of rail and stainless steel to investigate the influence of resonant frequency tracking speed on the crack detection. The results revealed that reducing the resonant frequency tracking time can efficiently improve defect detectability and the manufactured prototype showed more application potential. This article is part of the theme issue 'Advanced electromagnetic non-destructive evaluation and smart monitoring'.

Part distortion optimization of aluminum-based aircraft structures using finite element modeling and artificial neural networks

Currently, in the aircraft design, thinner structures are required to reduce weight, which in turn presents challenges for the manufacturing of parts and components. One of the identified problems in manufacturing is the machining distortion phenomenon, which causes the generation of scrap during the production of mechanical and structural components. This study presents the use of a finite element procedure, artificial neural network models, and the simulated annealing algorithm to optimize machining distortion phenomena in aluminum-based structures. A finite element procedure that simulates machining distortion by considering residual stresses and machining locations is used to generate training and validation data sets for the construction of an artificial neural network model. Once the performance of the artificial neural network is validated, simulated annealing is used in combination with the neural network model to find the optimum parameters of the machining locations and the residual stresses conditions that reduce distortion phenomena caused by machining. A case study of a specimen that has complex geometrical features, such as those that present in the design of aircraft structures, was used for the validation of the models. The results show that the proposed approach predicts the machining distortion of the specimen obtaining errors below 3% regarding experimental observations. Numerical results not only predict maximum distortions, but the evidence shows that the finite element can estimate the distribution of the distortion presented experimentally in the case study. Additionally, the optimization results helped to reduce the distortions 80% or more for high levels of deformation. Therefore, the proposed method in this study helps in the prediction and optimization of machining distortion of aluminum-based structures.

A Spectral-Aware Convolutional Neural Network for Pansharpening

Pansharpening aims at fusing a low-resolution multiband optical (MBO) image, such as a multispectral or a hyperspectral image, with the associated high-resolution panchromatic (PAN) image to yield a high spatial resolution MBO image. Though having achieved superior performances to traditional methods, existing convolutional neural network (CNN)-based pansharpening approaches are still faced with two challenges: alleviating the phenomenon of spectral distortion and improving the interpretation abilities of pansharpening CNNs. In this work, we develop a novel spectral-aware pansharpening neural network (SA-PNN). On the one hand, SA-PNN employs a network structure composed of a detail branch and an approximation branch, which is consistent with the detail injection framework; on the other hand, SA-PNN strengthens processing along the spectral dimension by using a spectral-aware strategy, which involves spatial feature transforms (SFTs) coupling the approximation branch with the detail branch as well as 3D convolution operations in the approximation branch. Our method is evaluated with experiments on real-world multispectral and hyperspectral datasets, verifying its excellent pansharpening performance.

Local Seeing Measurement for Increasing Astrophysical Observatory Quality Images Using an Autonomous Wireless Sensor Network.

Astrophysical observatories (AOs) are used to acquire high-quality images from the sky. However, AOs are amenable to distortion phenomena such as seeing. In this paper, we consider specifically the local seeing produced from indoor and outdoor temperature variations. Local seeing contributes to the captured image quality, therefore it must be measured. Local seeing has been considered, to the best of our knowledge, in observatories using ad hoc solutions, typically with high cost and complexity. This paper presents the complete development of an autonomous wireless sensor network (WSN) composed of temperature-measuring for real-time local seeing measurement. Therefore, a WSN is deployed using Zigbee as a data communication exchange. As a result, a long continuous-operating system is constructed and tested in a real AO infrastructure. Finally, we calculate a preliminary dome local seeing, from the acquired temperature data, achieving reasonable results.

A topology optimization method of robot lightweight design based on the finite element model of assembly and its applications.

Topology optimization is a widely used lightweight design method for structural design of the collaborative robot. In this article, a topology optimization method for the robot lightweight design is proposed based on finite element analysis of the assembly so as to get the minimized weight and to avoid the stress analysis distortion phenomenon that compared the conventional topology optimization method by adding equivalent confining forces at the analyzed part's boundary. For this method, the stress and deformation of the robot's parts are calculated based on the finite element analysis of the assembly model. Then, the structure of the parts is redesigned with the goal of minimized mass and the constraint of maximum displacement of the robot's end by topology optimization. The proposed method has the advantages of a better lightweight effect compared with the conventional one, which is demonstrated by a simple two-linkage robot lightweight design. Finally, the method is applied on a 5 degree of freedom upper-limb exoskeleton robot for lightweight design. Results show that there is a 10.4% reduction of the mass compared with the conventional method.

Wireless Body Area Networks: UWB Wearable Textile Antenna for Telemedicine and Mobile Health Systems.

A compact textile ultra-wideband (UWB) antenna with an electrical dimension of 0.24λo × 0.24λo × 0.009λo with microstrip line feed at lower edge and a frequency of operation of 2.96 GHz is proposed for UWB application. The analytical investigation using circuit theory concepts and the cavity model of the antenna is presented to validate the design. The main contribution of this paper is to propose a wearable antenna with wide impedance bandwidth of 118.68 % (2.96–11.6 GHz) applicable for UWB range of 3.1 to 10.6 GHz. The results present a maximum gain of 5.47 dBi at 7.3 GHz frequency. Moreover, this antenna exhibits Omni and quasi-Omni radiation patterns at various frequencies (4 GHz, 7 GHz and 10 GHz) for short-distance communication. The cutting notch and slot on the patch, and its effect on the antenna impedance to increase performance through current distribution is also presented. The time-domain characteristic of the proposed antenna is also discussed for the analysis of the pulse distortion phenomena. A constant group delay less than 1 ns is obtained over the entire operating impedance bandwidth (2.96–11.6 GHz) of the textile antenna in both situations, i.e., side by side and front to front. Linear phase consideration is also presented for both situations, as well as configurations of reception and transmission. An assessment of the effects of bending and humidity has been demonstrated by placing the antenna on the human body. The specific absorption rate (SAR) value was tested to show the radiation effect on the human body, and it was found that its impact on the human body SAR value is 1.68 W/kg, which indicates the safer limit to avoid radiation effects. Therefore, the proposed method is promising for telemedicine and mobile health systems.

Optimal design of passive filters considering the effect of Steinmetz circuit resonance under unbalanced and non‐sinusoidal conditions

In order to reduce the voltage unbalancing, the delta reactances connected to the single-phase load, known as the Steinmetz circuit, are utilised. In this study, the design of passive filters in presence of the Steinmetz circuit is presented to balance the unbalanced networks including single-phase load. Voltage distortion and resonance phenomenon are very serious problems in power systems. Some methods have been proposed to provide the solution to this problem, among which passive filters are used as the most economical and efficient way to reduce harmonics. In this research, in addition to a brief review of the passive filters and their common types, the objective functions of the issue are discussed. The optimised functions for this issue are total harmonic distortion,voltage deviation value, total filters cost, frequency response and the critical bus power factor of the network. To solve the problem of the suggested multi-objective optimisation, NSGA-II is presented, and finally, the best solution is proposed with the normalised method from among the Pareto front. To verify the effectiveness of the proposed method, two networks of 13-buses industrial test network and modified 33-buses IEEE network are evaluated. These networks are included non-linear loads and Steinmetz circuit.

Evidence of non-random mating in a colour polymorphic raptor, the Booted Eagle

Sexual selection and non-random mating are considered, among others, determinant mechanisms for the maintenance of genetic colour polymorphism in some bird species. We analyse the mechanisms, which, in parallel with Mendelian inheritance, may be acting in the maintenance and evolution of the morph ratio in a two-morph raptor species, using observational data of successful breeding individuals and their offspring from long-term studies conducted in three Spanish populations. Our results showed that the dark offspring produced in breeding events involving mixed-morph adult pairs far exceeds the expected value under the Hardy–Weinberg equilibrium, especially in the case of pairs formed by a light male and a dark female. In addition, the low number of dark eaglets born from pairs formed by light individuals (indistinctly homozygous or heterozygous) indicates that the number of breeding events of heterozygous (both the male and female) light morph pairs, was much lower than expected. As the plausible existence of a transmission ratio distortion phenomenon in heterozygous light morph males does not, alone, explain the disproportionate number of dark eaglets observed, our results suggest that one or two selective mating phenomena may be occurring in this polymorphic system. The first one could be a disassortative mating process whereby heterozygous light males preferentially mate with dark females, based on the imprint of the colour morph of their mother. The second phenomenon would only affect light morph individuals, which would preferentially mate with heterozygous individuals of the opposite sex, selected according to secondary sexual characteristics or behavioural traits that are unknown at the moment.

Research on adaptive pulse signal extraction algorithm based on fingertip video image

In order to solve the saturation distortion phenomenon of R component in fingertip video image, this paper proposes an iterative threshold segmentation algorithm, which adaptively generates the region to be detected for the R component, and extracts the human pulse signal by calculating the gray mean value of the region to be detected. The original pulse signal has baseline drift and high frequency noise. Combining with the characteristics of pulse signal, a zero phase digital filter is designed to filter out noise interference. Fingertip video images are collected on different smartphones, and the region to be detected is extracted by the algorithm proposed in this paper. Considering that the fingertip's pressure will be different during each measurement, this paper makes a comparative analysis of pulse signals extracted under different pressures. In order to verify the accuracy of the algorithm proposed in this paper in heart rate detection, a comparative experiment of heart rate detection was conducted. The results show that the algorithm proposed in this paper can accurately extract human heart rate information and has certain portability, which provides certain theoretical help for further development of physiological monitoring application on smartphone platform.

FENOMENA PEMAHAMAN DAN PENERAPAN HAKIKAT MAKNA KATA KEJAHATAN DAN PELANGGARAN DALAM PERKEMBANGAN HUKUM

The word crime and violation in the legal phenomenon of society experiences distortion when reviewing sanctions from the act. The word crime means that sanctions are classified as severe, whereas violations are assumed to contain mild sanctions. In further legal developments, legal / legal events or offenses are identified with just one word, namely acts, both those charged with that are philosophically crimes or those philosophically charged with violations. By knowing the fundamental differences between the separation of crime and violation with a philosophical approach, the community will have a strong basis for applying the law (academic theoretical and practical and or for the compiler, legislative law). Acts, events, offenses or Straafbaarfeit crimes in straafrecht, sub-system of criminal offenses, and sub-criminal offenses. Therefore, uniting these two things into acts only, contrary to the underlying thought and moral foundations. There are two factors that influence people's understanding of the nature of the meaning of the word crime and violation, namely: 1) Internal factors, the inability to interpret the meaning of the essence contained in these two things; 2). External factors, namely the existence of intentions to overturn the term for the sake of pragmatic interests and the inadvertence due to sources of information, news, literature, legislation that do not often mention and use these two terms in various legal events that occur in society.

DQ-Frame Zero-Crossing Effect Modeling and Current Distortion Compensation Method for Vienna Rectifier

Vienna rectifiers are widely used as front-end rectifiers in many applications because of their high efficiency and high power density. However, this topology has a problem that its current is always distorted near zero-crossing points, especially when the converter-side current ripples are large. This article reveals and models the zero-crossing current distortion phenomenon, which is caused by nonshared vectors of adjacent sectors when the sector detection error occurs. Near the zero-crossing points, the inevitably sector detection errors will occur due to the presence of the switching current ripples and other factors such as the control delay. The errors can be divided into two types, namely, the lag error, and the lead error. The effects of the two types of errors are equivalently modeled in the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dq</i> frame in this article. When the detection error occurs, it is equivalent to applying additional interference terms to the control output. Based on the equivalent error model, this article proposes two compensation methods to eliminate the zero-crossing effect caused by the sector error. The proposed methods are effective and easy-to-implement. Finally, simulation and experimental results validate the theoretical analysis.

基于改进动态大气散射系数函数的图像去雾方法

The invention discloses an image defogging method based on an improved dynamic atmospheric scattering coefficient function, and the method comprises the steps: solving a minimum channel image throughemploying R, G and B color channels of an original image, and calculating an atmospheric light value A of a foggy day image through a quadtree segmentation method; calculating the depth of field d (x)of the image by using a nonlinear color attenuation prior model, and filtering noise information in the depth of field d (x) of the image through minimum filtering, smooth filtering and guided filtering to obtain the final depth of field dr (x) of the image; and finally, in combination with the improved dynamic atmospheric scattering coefficient function beta (x) and the image depth of field dr (x) obtained through final processing, calculating atmospheric transmissivity t (x), and recovering a fog-free image through an atmospheric scattering model. The method not only can solve the problem of inaccurate transmissivity estimation caused by constant atmospheric scattering coefficient, but also can effectively solve the phenomenon of color distortion of the sky area of the image, so that the defogging effect of the image is clearer and more thorough, and the color of the scenery is more natural and real.