Circular Dimensions Research Articles

Er3+/ Yb3+ co-doped multi-functional silica phosphate glass films for integrated photonic applications

The multi-component silicate glasses co-doped with Er3+/Yb3+ were fabricated as thin films by the spin coating technique, which was analyzed for their optoelectronic response. Their monolith counterparts synthesized by the sol-gel route were used for the electrical studies. The films evidenced nanocristobalite phases at low levels of doping. The film micrographs explicated gas-trapped circular dimensions on the surface, due to the spreading of the sol on the substrate during the spin coating process. The glasses show a decrease in the number of polarizable non-bridging oxygen units with doping, reducing the polarizability and optical basicity. The films exhibit prominent green lasing in the downshifting process. The energy transfer from the Yb3+ ions endows the glasses with significant red lasing, suppressing the green emissions by the upconversion mechanism, which is also validated by the colorimetric chromaticity analysis. The gain cross-section of the glass doped with 1.5 mol% of Yb3+ is 23.3 × 10−20 cm2 in the S-band telecommunication domain. The glass film evidences its potential for NIR lasers, beyond a population inversion of 40 %, and a decreasing metastable lifetime of 6.6 μs. Beyond 1.5 mol% of the co-dopant Yb3+, energy transfer dominates, due to the dipole-quadrupole interactions, which has been corroborated by the Inokuti-Hirayama model. The conductivity in the glasses shows a decreasing trend with doping. The Randle's equivalent circuitry of the Nyquist impedance plots, predicts Warburg diffusion impedance that deters the space charge polarization. The consequential decrease in the dielectric constant and capacitance makes the glasses suggestive of multi-layer dielectric substrates in the integrated microelectronic technology for soldering of the printed circuit boards (PCB) that demand low signal losses.

Intragenerational Dynamics in the Indonesian Oil Palm Growth Zone: The Resolution between Circular Dimensions and Human Capital

Intragenerational Dynamics in the Indonesian Oil Palm Growth Zone: The Resolution between Circular Dimensions and Human Capital

Vision-based measurement method for geometric dimensions of PVC pipe end faces

This study introduces a vision-based expedited methodology for assessing various geometric circular dimensions on the termini of PVC conduits. The process commences with delineating pipe profiles using the EDPF algorithm for edge detection. Successive steps employ a radius-constrained weighted circular approximation algorithm to form provisional circular profiles from closed-edge segments. These profiles are refined using a rapid circle arc fitting algorithm for multiple open-edge sections. Noise circles are sifted out with the Number of False Alarms algorithm, and upon calibration with actual dimensions, these profiles are quantified into physical sizes of the conduit's terminal geometries. Empirical evidence from the methodology demonstrates an ability to measure the circular dimensions with a mean accuracy rate surpassing 99.2%.

Assessing the resilience of circularity in water management: a modeling framework to redesign and stress-test regional systems under uncertainty

ABSTRACT Contrary to the ‘make-use-dispose’ linearity of conventional management, circular economy design principles have been proposed as a resource management alternative that reduces waste and promotes efficiency. These principles also find use in water management, offering an alternative against centralized models. Despite the intrinsic links between circularity and resilience, few studies have advanced the identification and discussion of linkage beyond a theoretical or conceptual level. This study presents quantitative links between circularity and resilience, by demonstrating how different circular water management strategies lead to improved resilience performance for a regional urban-rural water system. A stress-testing framework based on a water cycle model is presented, where different circular interventions are evaluated in terms of their overall resilience against future uncertainty. The results demonstrate that circular water options lead to more resilient water systems. The more circular dimensions are addressed through interventions, the more robust resilience profiles become across different water cycle domains.

INVESTIGATION ON HEAT TRANSFER IN CIRCULAR FINS WITH H-SHAPED CAVITY USING FINITE ELEMENT METHOD AND CONSTRUCTAL DESIGN

Through constructal design, this study examines how the geometrical configuration of channels embedded within an object in the presence of internal heat generation can be utilized for cooling through convection heat transfer. During the present study, the cavity is cooled by the convection heat transfer method. This work aims to provide an optimal tree structure for cooling electronic components with circular dimensions and internal heat generation in an H-shaped cavity. A structure for this purpose must be designed so that the maximum temperature obtained in the desired surface area is reduced to the minimum for a given production heat power. A study will also examine the dimensions of specific channels in order to decrease the maximum temperature that will be produced. In addition, it will study the geometric characteristics of the branching of the channels and their length. The finite element method will be used to simulate the heat transfer process. Following the validation of the created model, numerous parameters will be checked on the maximum temperature generated in the system. The results will be presented and discussed in appropriate charts and tables.

Stitched Transmission Line for Broadband Operations

Wearable stitched transmission lines made from stripped RG174 and textile materials are introduced for broadband operations. The stitched transmission lines which are 150 mm long consists of an inner conductor surrounded by a tubular insulating layer. For shielding purposes, the structures are stitched into a denim material with conductive threads. The performances of the stitched transmission lines with three different stitch patterns, Double Overlock, Flatlock stitch and Ric-Rac stitch were investigated and results obtained confirm that Ric-Rac stitched transmission line has fewer DC losses than the three stitched transmission lines for frequencies up to 1 𝐺𝐻𝑧. However, beyond that up to 2.4 𝐺𝐻𝑧 and above, it was observed that the Flatlock stitched transmission line and the Double Overlock stitched transmission line have fewer radiation losses compared to the Ric-Rac stitched transmission line. Similarly, the performance of the stitched transmission line when bent through curved angles of 90° and 180° was considered, and a much better 𝑆ଶଵ was observed with a curved angle of 180° for frequencies below 2.1 𝐺𝐻𝑧, with radiation loss increasing afterwards. Finally, the sensitivity of the design to manufacturing tolerances, with changes in cross-sectional dimensions of the stitched transmission line and the transmission characteristics with different textile substrates were both considered. While simulated results showed that the stitched transmission line is sensitive to small variations in its circular dimensions, measured results conversely showed that Denim and Felt materials can be used as a substrate without any significant effect on its propagation characteristics.

ANTHROPOMETRIC CHARACTERISTICS AND AGILITY OF WHEELCHAIR BASKETBALL PLAYERS : DIFFERENCES AND RELATIONSHIP WITH FUNCTIONAL CLASSIFICATION

The aim of this study was to determine: (1) differences in anthropometric characteristics and agility between different functional classes of wheelchair basketball players and (2) the relationship between anthropometric characteristics and agility with the functional classification of wheelchair basketball players. The sample of participants consisted of 40 wheelchair basketball players, aged 33.9 ± 11.2 years. Anthropometric characteristics (longitudinal and circular dimensions, as well as skinfold thickness) were assessed, and agility was measured using the modified T-test and Figure-of-Eight test. The results of the one-way analysis of variance showed significant differences with very large effects between players of different functional classes in body mass, sitting height, and sitting reach height, while significant differences with large effects were recorded in the agility assessment tests: the T-test and the Figure-of-Eight test. Also, the results of the correlation analysis indicate that there are significant moderate positive correlations of sitting height and reaching height with functional classification.

Coloured hearing, colour music, colour organs, and the search for perceptually meaningful correspondences between colour and sound.

There has long been interest in the nature of the relationship(s) between hue and pitch or, in other words, between colour and musical/pure tones, stretching back at least as far as Newton, Goethe, Helmholtz, and beyond. In this narrative historical review, we take a closer look at the motivations that have lain behind the various assertions that have been made in the literature concerning the analogies, and possible perceptual similarities, between colour and sound. During the last century, a number of experimental psychologists have also investigated the nature of the correspondence between these two primary dimensions of perceptual experience. The multitude of different crossmodal mappings that have been put forward over the centuries are summarized, and a distinction drawn between physical/structural and psychological correspondences. The latter being further sub-divided into perceptual and affective categories. Interest in physical correspondences has typically been motivated by the structural similarities (analogous mappings) between the organization of perceptible dimensions of auditory and visual experience. Emphasis has been placed both on the similarity in terms of the number of basic categories into which pitch and colour can be arranged and also on the fact that both can be conceptualized as circular dimensions. A distinction is drawn between those commentators who have argued for a dimensional alignment of pitch and hue (based on a structural mapping), and those who appear to have been motivated by the existence of specific correspondences between particular pairs of auditory and visual stimuli instead (often, as we will see, based on the idiosyncratic correspondences that have been reported by synaesthetes). Ultimately, though, the emotional-mediation account would currently appear to provide the most parsimonious account for whatever affinity the majority of people experience between musical sounds and colour.

INFLUENCE OF MORPHOLOGICAL CHARACTERISTICS ON THE PARAMETERS OF HEALTH-RELATED FITNESS IN OVERWEIGHT AND OBESЕ BOYS

The aim of this study was to determine the influence of morphological characteristics on the health–related fitness parameters in overweight and obese eight-year-old boys. The research involved 314 boys who attended second grade in the cities of South-East Serbia. The parameters of longitudinal (3), transversal, (3) circular dimensions (3), and body mass and measurement of subcutaneous adipose tissue (3) were used to assess morphological characteristics. Health-related fitness parameters were determined using tests to assess muscle fitness, body composition and cardiorespiratory fitness. Regression analysis was used to determine the influence of morphological characteristics on the parameters of health-related fitness. The results of the research indicate that there is a statistically significant influence (p=.000) of morphological characteristics on most parameters of health-related fitness. No statistically significant effect was found in the forward bend - backward bend - throw test ∑ in the studied sample.

FITNESS PARAMETERS AND MORPHOLOGICAL CHARACTERISTICS OF OVERWEIGHT AND OBESE CHILDREN AGED SEVEN

The aim of the research was to determine the correlation of morphological characteristics and fitness parameters of overweight and obese boys aged seven. The sample of participants consisted of 198 pupils (boys) aged seven years, from elementary schools from the territory of the city of Niš, Paraćin, Bela Palanka, Leskovac and others, classified as a category with increased body mass or obesity. Morphological characteristics were determined by measuring parameters of longitudinal (3), transversal, (3) circular dimensions (3) and body mass and measurement of subcutaneous fat tissue (3). For the assessment of muscular fitness, body composition and cardiorespiratory fitness, the following tests were used: the plyometric leap, precancer-turn-off, percentage of body fat and Body Mass Index (BMI); a shuttle run test based on the calculated VO2max (L) and VO2max (ml/kg/min) values. A canonical correlation analysis was used to determine the correlation between morphological characteristics and fitness parameters. The level of statistical significance was set at .05. The results of the study showed that there is a statistically significant association (p˂.01) between morphological characteristics and fitness parameters in overweight and obese boys aged seven. Participants who have higher values of voluminosity and body width have higher values of fat percentage in the body as well as BMI. Smaller explosive power was found in participants with higher values of skin folds. It has been determined that body mass and voluminosity positively affects the strength of the arm and shoulders, that is, they adversely affect the VO2max values.

The effects of acrobatics on morphological characteristics of school children

The aim of this paper is to determine the effects of acrobatic elements on changes in morphological characteristics in children who were experimentally treated. The sample consists of elementary school children from Kosovska Mitrovica N = 52, who regularly attend physical education classes and additional acrobatics trainings three times a week for the implementation of acrobatics in additional classes of physical education. The variables used to assess the circular dimensions and body mass are: Upper arm circumference expressed in cm (AONDL), calf circumference expressed in cm (AOPTK), chest circumference expressed in cm AOGRK, body weight expressed in kg (AMAST). The variables used to estimate the subcutaneous fat tissue are: Upper-arm skinfold expressed in mm (ANNDL), calf skinfold expressed in mm (ANPTK), Abdominal skinfold expressed in mm ANTRB. A t-test was used to determine statistically significant differences in variables (ANNDL p=.006), (ANPTK p=.005), (ANTRB p=.008). The obtained results can contribute to the rationalization of regular and additional teaching of physical education for the optimal planning and control of work.

The relationship between body alometry and gait transition speed of human locomotion

Walking and running represent the two basic, fundamental patterns of human locomotion. The lowest speed at which a man spontaneously switches from walking to running is called preferred transition speed (PTS). There are a considerable number of inconsistencies regarding the importance and influence of body size and muscle factors in the phenomenon of gait transition speed, in the previous research findings. The objectives of this study were to determine: (1) the relationship between longitudinal, transversal and circular dimensions of the body and PTS; (2) the relationship between body proportions and PTS; (3) the relationship between body composition variables and PTS; (4) the predictive power of human allometry in determination of PTS. The sample comprised 59 male subjects (age 21.76 ± 1.93 years) heterogeneous in physical dimensions. We measured 15 anthropometric variables, body composition, and determined individual PTS using the standard increment protocol. Statistical analysis included Pearson correlation and Multivariate linear regression. The value of PTS in this study was 7.96 ± 0.38 km h-1. the highest correlations with PTS were recorded for variable lower leg length (r = -0.488), foot length (r = 0.418) and leg length (r = -0.410, p < 0.01). Body proportions showed higher correlations with the PTS in compare to individual anthropometric variables, and the highest correlation was observed between the proportion of the thigh length/lower leg length and PTS (r = 0.521, p < 0.01). The amount of body fat and percentage of body fat had low inverse correlation with PTS (r = -0.250, p < 0.05). Linear regression showed that 31% of the PTS variance can be explained by the variables lower leg length and foot length. Results of hierarchical regression showed that the 50.4% of the PTS variance can be explained through four body proportions. The main results of this experiment indicate that the proportions of the body are better PTS predictors in compare to the individual anthropometric variables. This means that body constitution, and especially the proportions between the leg segments and percent of the leg muscle mass, are more important PTS determinants than length of individual body segments.

Differences between young judokas and untrained subjects in anthropometric and motor features

It has been shown that more successful judokas have better motor features than less successful ones [1] , [2] or untrained [3] , [4] . Thus, judo training could be beneficial for the development of children. The purpose of this study was to evaluate the effects of additional judo training on anthropometric characteristics and motor abilities in school children. The 60 minutes judo treatment was applied twice a week during one school year (9 months) in 35 school boys (8.25 ± 0.28 years). A control group of 37 boys (8.37 ± 1.48 years) trained according to the regular program for school institutions, and did not participate in any other organized physical activity. Treatment effects were assessed by motor ability tests: obstacle course backwards and slalom with 3 balls (coordination), arm plate tapping (motion frequency), sit-and-reach (flexibility), bent-arm hang and sit-ups with crossed arms (muscular endurance), standing broad jump (explosive strength), and 20-m dash (speed of running); and by anthropometric measurements: height, weight, girths (stretched upper-arm, forearm and chest), skinfolds (abdominal, subscapular, triceps). Groups were compared by a t -Student test. Children which performed the judo training had higher girths (Upper-arm and Forearm) than the control group at the end of the school year. In addition, the experimental group had better results in the tests for assessment speed (20-m dash), coordination (obstacle course backwards), motion frequency (arm plate tapping), endurance (bent arm hang), and repetitive strength (crossed-arm sit-ups) than controls. Results point to the importance of physical exercise and the application of additional judo activities in order to improve motor abilities and morphological growth in school children. The development of strength, coordination, speed, and the increase of circular dimensions, likely achieved by the additional judo training, imposes an initiative to implement certain types and principles of judo training into daily physical education lessons at the school level.

Differences in longitudinal and circular body dimensions of students aged 13 measured in 1970 and 1995

During school age tracking the student growth and development enables us to assess the regularity of the developmental period. By measuring the morphological measures we are coming to the data on the growth and development of student as a whole and in individual segments of the body. If we want to get to the fact if there is acceleration in the growth and development, it is necessary to compare the growth and development, with the growth and development of student the same age measured more than twenty years ago. The aim of this study was to determine the difference in longitudinal and circular skeleton dimensions of student 13 years old measured in 1970 and 1995 year. Morphological measurements were performed by standard instruments by the methodology recommended by the International Biological Program (IBP). Determination of differences was done by using the Difference test from the statistical package Statistica 8.0 for Windows, considering data of means and standard deviations of respondents. The results indicate that the students who are measured in 1995 have bigger longitudinal and circular dimensions as compared to students of the same age measured in 1970 year.

DESIGN, DEVELOPMENT AND NUMERICAL ANALYSIS OF HONEYCOMB CORE WITH VARIABLE CRUSHING STRENGTH

A honeycomb core with half-circular cut-away sections at the spine (the adjoining cell walls) is designed and developed and numerically tested under axial dynamic load condition. The parametric study is invoked to identify the effect of various circular cut-away dimensions. In one embodiment a half-circular shaped cuts are removed from the top of the cell where the cell is impacted and its radius decreases toward the trailing edge of the cell. Numerical (FE) analysis was performed using explicit ANSYS/LS-DYNA and LS-DYNA codes to investigate the crushing performance, where impact angles 30° and 90° was combined with velocity of 5:3 m/sec. The crushing strength and internal energy absorption of the modified honeycomb cores with cut-away sections are then monitored to define the design parameters. The representative Y-section (axisymmetric model) is used for numerical analysis which simulates the honeycomb crushing performance. The numerical results of these innovative models show cyclic buckling effect in which crushing strength increases linearly as the rigid wall passes through. The FE results are validated with corresponding published experiments of the original unmodified honeycomb core (without cut-away).

Automation of crack recording in brittle tensosensitive coatings

Application of numerical technologies of digital image processing to the automation of crack pattern recording in brittle tensosensitive coatings is considered. The technique of orthotransformation of perspective pictures of crack patterns in tensosensitive coatings is described, which includes the following stages: the formation of a triangulation wireframe model of the structural element under study; selection of reference points for calculating the relative position of the object and camera at the photographing moment; determination of angular and spatial coordinates of the object position with respect to the camera; orthotransformation a separated area of a perspective image projection in the photograph; overlapping the orthotransformed image on the triangulation wireframe model of the structure under study. An example of application of the technique is shown for processing of the crack pattern in a brittle tensosensitive coating obtained during tensile testing of an aviation panel sample. Errors of distortions of linear and circular dimensions for the separated aviation panel element did not exceed 5% of actual values.

Les tournois de Melyador, ou l’originalité d’une stéréotypie stylisée

Jean Froissart’s Melyador belongs to the tradition of courtly chivalric romances. In the most faithful fashion, this romance stages four large tournaments upon which rest the whole work’s architecture and love intrigues. Studying these conventional pieces shows that they replicate and take on the theme’s inherent share of stereotypes, although they also transcend these stereotypes and turn them into a mode of aesthetic renewal. The stereotypical nature of the tournament episodes is indeed both generalized and reduced to its essence, while it is very stylized to the point of bestowing lyrical and circular dimensions to the episodes. Thus, in Melyador, the time of the chivalric performance meets up in a very original fashion with the poetical dimension of the work.

A monolithic GaAs-based short wavelength smart pixel based on fabricated p–i–n PD, aDHBT and a VCSEL

For the first time a smart pixel that can function as a building block for an optical transceiverwith circular dimensions is fabricated using an InGaP/GaAs double heterojunction bipolartransistor (DHBT) and a GaAs/AlGaAs vertical cavity surface emitting laser (VCSEL). Anovel InGaP DHBT structure based on an abrupt base–collector heterojunction, theδ+-layer composite collector structure, is employed in this work. The DHBTshowed a breakdown voltage of 13 V and a cut-off frequency of 32 GHz atIc = 30 mA. Also a high performance 850 nm infrared VCSEL exhibited athreshold current of 3.5 mA with a maximum optical output of 4.8 mW atIc = 20 mA and forward voltage of 1.8 V. The detector, comprising the base-to-collectorjunction of the DHBT as a p–i–n photodiode (PD), produced a photocurrent of180 µA for a given input power of 0.3 mW.

Fabrication and characterization of a monolithic InP-based long wavelength smartpixel

For the first time a smart pixel that can function as a building block of an optical transceiverwith circular dimensions is fabricated using an InP/InGaAs double-heterojunction bipolartransistor (DHBT) and an AlGaInAs/InP vertical cavity surface emitting laser (VCSEL).The DHBT showed a breakdown voltage of 12 V and a cut-off frequency of 42 GHz atIc = 30 mA. Also a high performance 1550 nm VCSEL exhibited a thresholdcurrent of 3.5 mA with a maximum optical output of 4.8 mW atIc = 20 mA and forward voltage of 1.8 V. The detector, comprised of the base-to-collectorjunction of the DHBT as a p–i–n PD, produced a photocurrent of200 µA for a given input power of 0.3 mW.

Simulation studies of a 2 Gb s−1 monolithic integrated smart pixel based on fabricated p-i-n PD, DHBT and a VCSEL

A smart pixel that can function as a building block of an optical transceiver with circular dimensions is proposed using InGaP/GaAs double heterojunction bipolar transistors (DHBTs) and a GaAs/AlGaAs vertical cavity surface emitting laser (VCSEL). Fabricated DHBT showed a breakdown voltage of 13 V and a cut-off frequency of 35 GHz at Ic = 30 mA. Also a high-performance 850 nm infra-red VCSEL exhibited a threshold current of 3.5 mA with a maximum optical output of 4.8 mW at Ic = 20 mA and forward voltage of 1.8 V. The detector, comprised of the base-to-collector junction of the DHBT as a pin-PD, produced a photocurrent of 180 µA for a given input power of 0.3 mW. The extracted small-signal equivalent circuit parameters from measurement of these devices were used in PSPICE simulations to design an interface drive circuit for high-speed modulation. The overall OEIC circuit performance operates up to data rates of 2 Gb s−1 at 1 mW output power with maximum output voltage of 2 V across the VCSEL and modulation current of 5 mA.