Determining a Tracer Diffusivity by way of the Darken-Manning Equation for Interdiffusion in Binary Alloy Systems

2015 ◽  
Vol 4 ◽  
pp. 25-54 ◽  
Author(s):  
T.R. Paul ◽  
I.V. Belova ◽  
E.V. Levchenko ◽  
A.V. Evteev ◽  
G.E. Murch
Keyword(s):  
Binary Alloy ◽  
High Sensitivity ◽  
Thermodynamic Factor ◽  
Tracer Diffusivity ◽  
Self Diffusion ◽  
Medium Level ◽  
Random Alloy ◽  
High Level ◽  
Self Diffusion Coefficient ◽  
Different Levels

The self-or tracer diffusivity of one component in a binary alloy is often required when there is knowledge of the other component’s self-or tracer diffusivity and the interdiffusivity (and the thermodynamic factor). In the present paper, this problem is addressed for the random alloy model by applying three possible approximations having different levels of accuracy: Darken (low level of accuracy), Manning (medium level of accuracy) and Moleko, Allnatt and Allnatt (MAA) (high level of accuracy). There are unexpectedly large differences between the results of these approximations that sometimes are reflected in the high sensitivity of the vacancy-wind factor to the level of approximation. Generally, for the application of Manning and the MAA approximations, it is found that there is a difference in the number of self-diffusivity roots depending on whether the tracer diffusivity is available for the faster diffuser or for the slower diffuser and depending on how close the composition is to the forbidden (according to Manning’s description) region. Provided that the interdiffusion coefficient (divided by the thermodynamic factor) is greater than the available self-diffusion coefficient multiplied by its complementary composition, the application of the Darken approximation always results in one self-diffusivity root.

Level of feeding during early life and the subsequent reproductive performance of sows

1961 ◽  
Vol 3 (1) ◽  
pp. 19-28 ◽  
Author(s):  
G. A. Lodge ◽  
R. M. McPherson
Keyword(s):  
Live Weight ◽  
Feed Conversion ◽  
Treatment Groups ◽  
Litter Weight ◽  
Significant Difference ◽  
Medium Level ◽  
Plane Group ◽  
High Level ◽  
Different Levels ◽  
Size At Birth

1. Nine groups of 4 litter-mate Wessex Saddleback gilts were divided on a within-litter basis between 4 treatments so that they were reared from 8 weeks of age to 200 1b. live-weight according to different levels of total feed intake; (a) a high level rising to 8·0 1b. meal per day at 200 1b. live-weight, (b) a medium level approximately 80% of the high, (c) a low level approximately 60% of the high and (d) changing from the low to the medium level between 14 and 16 weeks of age. From 200 1b. live-weight to mating at first heat after reaching 300 1b. all were fed to the medium scale (6·5 1b. meal per day), and all were treated alike during each of 3 pregnancies and lactations.2. Mean rate of growth from weaning to 100 1b. and from 100 to 200 1b. differed significantly between treatments (P<0·001), and mean efficiency of feed conversion of the low-plane group was significantly poorer than that of the high-plane group (P<0·05) from weaning to 100 1b. live-weight.3. All gilts, regardless of treatment, reached puberty at approximately the same age (25 weeks), with the result that mean weight at puberty differed markedly between treatments (P<0·001); 116, 154, 189 and 147 1b. for treatments (a) to (d) respectively.4. Gilts reared on medium and high planes of feeding exhibited oestrus less strongly than those reared on the low-plane, with the result that mean weight at successful mating was significantly greater in these two groups (P<0·05).5. Four gilts in the low-plane group and one in the high-plane group failed to conceive after repeated matings, but numbers were insufficient to indicate the significance of this.6. From the original 36 gilts, 27 first litters, 26 second litters and 25 third litters were produced and reared to 8 weeks of age. There was no significant difference between treatment groups in litter size at birth, mean weight of piglets at 3 or 8 weeks of age or total litter weight at weaning.7. Trouble from temporary collapse of the legs was experienced in all but one gilt of the high-plane group between 6½ and 7½ months of age.

The Impact of Perceived Visual Complexity, Gender, and Cognitive Style on Children's Aesthetic Preferences for Learning Web Pages

2014 ◽  
pp. 248-265
Author(s):  
Hsiu-Feng Wang ◽  
Pei-Yu Wang ◽  
Ching-Chih Liao ◽  
Yu-Yin Lin
Keyword(s):  
Cognitive Style ◽  
Visual Complexity ◽  
Web Pages ◽  
Aesthetic Preference ◽  
Subject Design ◽  
Medium Level ◽  
High Level ◽  
The Impact ◽  
Different Levels ◽  
Aesthetic Preferences

This chapter examines children's aesthetic preferences for learning Web pages designed for them. It applies Berlyne's theory of aesthetic preference to these Web pages: a theory that suggests that people prefer a medium level of stimuli to a low or high level of stimuli. The experiment employs a 3 x 2 x 2 between-subject design; it explores perceived visual complexity, gender, cognitive style, and aesthetic preference. A total of 120 children (60 boys and 60 girls) aged between 11 to 12 years-old take part in the experiment. The children are asked to rate learning Web pages of different levels of perceived visual complexity for aesthetic preference. These Web pages have been created by the authors. The results of the experiment show that overall the children prefer Web pages that display a medium level of perceived visual complexity to those that display a high or low level of perceived visual complexity. Thus, the results support Berlyne's theory. However, when aesthetic preference is analysed with respect to gender, it is found that different levels of perceived visual complexity have an impact on boys' aesthetic preferences but not girls'. In other words, Berylne's theory is only partly supported. Likewise, Berylne's theory is only partly supported when aesthetic preference is analysed with respect to cognitive style. Here, imagers prefer a high level of perceived visual complexity and verbalisers prefer a medium level of perceived visual complexity. This chapter should be of interest to anyone who designs learning Web pages for children.

“Think of the Children!”

2019 ◽  
pp. 235-254
Author(s):  
Hsiu-Feng Wang
Keyword(s):  
Visual Complexity ◽  
Learning Motivation ◽  
Older Children ◽  
Aesthetic Preference ◽  
Low Level ◽  
Visual Aesthetics ◽  
Age Related ◽  
Medium Level ◽  
High Level ◽  
Different Levels

This experiment examined children's visual aesthetics and learning motivation with regard to websites. It applied Berlyne's theory of aesthetic preference to these websites. The experiment explored the relations between visual complexity, visual aesthetics, learning motivation, and children's age, and their effect on websites. A total of 150 children between 10 and 12 years old were involved. The children were asked to rate websites of different levels of perceived visual complexity in terms of visual aesthetic and learning motivation. The results showed that the children preferred websites that displayed a medium level of perceived visual complexity to those that displayed a high or low level of perceived visual complexity. Thus, the results supported Berlyne's theory. However, when aesthetic preference was analyzed with respect to age-related differences, it was found that older children preferred a medium level of perceived visual complexity and younger children preferred a high level of perceived visual complexity.

scholarly journals Verbal Expression of Preparedness in Retirement Planning Interviews

2020 ◽  
Vol 7 (2) ◽  
Author(s):  
Liudmyla Mahdysiuk ◽  
Halyna Tryhub ◽  
Tamara Duchiminska ◽  
Anna Kulchytska ◽  
Larysa Zasiekina
Keyword(s):  
Positive Emotions ◽  
Total Population ◽  
Assessment Data ◽  
Structured Interviews ◽  
Government Officials ◽  
Retirement Preparedness ◽  
Medium Level ◽  
Linguistic Inquiry ◽  
High Level ◽  
Different Levels

Conceptualization of retirement requires interdisciplinary research, which is represented by psycholinguistic approach in the present paper. The study takes a first step to explore conceptualization of retirement by individuals with different levels of retirement preparedness. The study applies questionnaire Psychological Preparedness for Retirement (Zasiekina & Mahdysiuk, 2018) to assess levels of preparedness; semi-structured interviews to focus primarily on concerns related to planning postretirement period; Linguistic Inquiry and Word Count (LIWC) (Tausczik & Pennebaker, 2010) to reveal psychological categories and explore conceptualization of retirement.  By the end of the assessment, data had been collected from 117 workers who were at preretirement period. The sample was weighted by age and occupation in order to improve its representative of the total population 22 (18.8%) – university staff, teachers at colleges, 18 (15.4%), nurses in kindergartens, 8 (6.6%), healthcare staff, 18 (15.4%), government officials, 28 (23.9%), workers from private sector, 23 (19.7%). The final weighted sample includes 65.8% females, average age 54.52, (SD=6.21). The results indicate that 8.5% respondents have a low level of preparedness, 61.5% - a medium level of preparedness and 30% - a high level of preparedness. Interestingly, the highest percentage of categories of affect and positive emotions were observed in the group with a medium level of preparedness, whereas the highest percentage of categories cause, focus on present, and family were captured in the group with a high level of preparedness. Taken together, these results suggest that the high level of retirement preparedness is associated with active cognitive reappraisal of retirement as a period of family activities.

scholarly journals CHALLENGES FACING DISTANCE LEARNING IN THE NEGEV REGION

2021 ◽  
Vol 3 (1) ◽  
pp. 378-389
Author(s):  
Mawaheb Shehadeh ALKRRENAWI ◽  
Keyword(s):  
Distance Learning ◽  
Survey Method ◽  
Years Of Experience ◽  
Arithmetic Average ◽  
Academic Qualification ◽  
Preparatory Schools ◽  
Medium Level ◽  
The Difference ◽  
High Level ◽  
Different Levels

The study aimed to identify the level of challenges facing distance learning in preparatory schools within the Negev region from the teachers' point of view, and to reveal the difference in their views towards the challenges facing distance learning in the schools of the Negev region according to different levels of (Gender, Academic qualification, and Years of experience) variables. The study used the sample social survey method, and the questionnaire as a tool for collecting data. The study sample consisted of (302) teachers who were selected from preparatory schools in the Negev region, besides, the questionnaire was applied via websites to the targeted sample. The results showed that the total level of challenges facing distance learning in schools within the Negev region came at a High level, with an arithmetic average (3.818), as the Economic challenges area came first with an arithmetic average (4.208) and a High level, the Technological challenges area came second with an arithmetic average (4.119) and a high level, the Teacher-related challenges area came third with an arithmetic average (3.580) and a Medium level, and in the area Student-related challenges area came fourth with an Arithmetic average (3.365) and a Medium level. The results also showed that there were no statistically significant differences at the level of significance (α = 0.05) in the averages of the study sample responses about the challenges facing distance learning in the schools within the Negev region attributed to the different levels of Gender and Academic qualification variables, while there were statistically significant differences at (α = 0.05) due to the difference in the Years of experience variable in favor of those with long experience.

Biological effects of low-intensity radiofrequency fields and risk assessment for biota

2020 ◽  
Vol 60 (9) ◽  
pp. 592-596
Author(s):  
Elena I. Sarapultseva ◽  
Darya V. Uskalova ◽  
Ksenya V. Ustenko
Keyword(s):  
Radio Frequency ◽  
Electromagnetic Radiation ◽  
Electromagnetic Fields ◽  
Negative Impact ◽  
Biological Effects ◽  
High Sensitivity ◽  
Communication Technologies ◽  
Natural Ecosystems ◽  
Low Intensity ◽  
Different Levels

Despite the fact that there are still conflicting opinions about the damage caused by modern wireless communication technologies, most scientists report on the negative biological effects of low-intensity radio frequency electromagnetic radiation at different levels of the organization of live nature. There is no doubt that there is a need not only for a sanitary and hygienic assessment of man-made electromagnetic effects on humans, but also for an environmental assessment for biota. The purpose of the study was to assess the potential environmental risk of electromagnetic impact in the centimeter range on natural ecosystems. The initial data were the authors' own results in the field of radiobiology of non-ionizing radiation, as well as published of other researchers. The article analyzes the biological effects of radio frequency electromagnetic fields detected in organisms of different systematic groups and levels of organization. The data on the non-thermal biological effects of electromagnetic fields indicate a high sensitivity of different species to this factor. The analyzed research results emphasize the need to take into account the features of non-thermal effects of electromagnetic radiation on biota, since these radiations can have a negative impact on different hierarchical levels in natural ecosystems.

scholarly journals Aircraft Requirements for Sustainable Regional Aviation

Aerospace ◽  
2021 ◽  
Vol 8 (3) ◽  
pp. 61
Author(s):  
Dominik Eisenhut ◽  
Nicolas Moebs ◽  
Evert Windels ◽  
Dominique Bergmann ◽  
Ingmar Geiß ◽  
...  
Keyword(s):  
Systems Engineering ◽  
System Level ◽  
Policy Initiative ◽  
The European Union ◽  
Calculation Methods ◽  
Figures Of Merit ◽  
Performance Requirements ◽  
High Level ◽  
Different Levels ◽  
The Eu

Recently, the new Green Deal policy initiative was presented by the European Union. The EU aims to achieve a sustainable future and be the first climate-neutral continent by 2050. It targets all of the continent’s industries, meaning aviation must contribute to these changes as well. By employing a systems engineering approach, this high-level task can be split into different levels to get from the vision to the relevant system or product itself. Part of this iterative process involves the aircraft requirements, which make the goals more achievable on the system level and allow validation of whether the designed systems fulfill these requirements. Within this work, the top-level aircraft requirements (TLARs) for a hybrid-electric regional aircraft for up to 50 passengers are presented. Apart from performance requirements, other requirements, like environmental ones, are also included. To check whether these requirements are fulfilled, different reference missions were defined which challenge various extremes within the requirements. Furthermore, figures of merit are established, providing a way of validating and comparing different aircraft designs. The modular structure of these aircraft designs ensures the possibility of evaluating different architectures and adapting these figures if necessary. Moreover, different criteria can be accounted for, or their calculation methods or weighting can be changed.

Urban network of China from the perspective of population mobility: Three-dimensional co-occurrence of nodes and links

2021 ◽  
pp. 0308518X2199781
Author(s):  
Xinyue Luo ◽  
Mingxing Chen
Keyword(s):  
Three Dimensional ◽  
Geographical Distance ◽  
Two Dimensional ◽  
Population Mobility ◽  
Urban Network ◽  
Urban Networks ◽  
Low Level ◽  
Medium Level ◽  
High Level ◽  
External Connections

The nodes and links in urban networks are usually presented in a two-dimensional(2D) view. The co-occurrence of nodes and links can also be realized from a three-dimensional(3D) perspective to make the characteristics of urban network more intuitively revealed. Our result shows that the external connections of high-level cities are mainly affected by the level of cities(nodes) and less affected by geographical distance, while medium-level cities are affected by the interaction of the level of cities(nodes) and geographical distance. The external connections of low-level cities are greatly restricted by geographical distance.

scholarly journals Mutual Impact between Clock Gating and High Level Synthesis in Reconfigurable Hardware Accelerators

Electronics ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 73
Author(s):  
Francesco Ratto ◽  
Tiziana Fanni ◽  
Luigi Raffo ◽  
Carlo Sau
Keyword(s):  
Low Power ◽  
Integrated Circuit ◽  
Systems Design ◽  
Hardware Acceleration ◽  
High Level Synthesis ◽  
Clock Gating ◽  
Technology Application ◽  
Positive Effects ◽  
High Level ◽  
Different Levels

With the diffusion of cyber-physical systems and internet of things, adaptivity and low power consumption became of primary importance in digital systems design. Reconfigurable heterogeneous platforms seem to be one of the most suitable choices to cope with such challenging context. However, their development and power optimization are not trivial, especially considering hardware acceleration components. On the one hand high level synthesis could simplify the design of such kind of systems, but on the other hand it can limit the positive effects of the adopted power saving techniques. In this work, the mutual impact of different high level synthesis tools and the application of the well known clock gating strategy in the development of reconfigurable accelerators is studied. The aim is to optimize a clock gating application according to the chosen high level synthesis engine and target technology (Application Specific Integrated Circuit (ASIC) or Field Programmable Gate Array (FPGA)). Different levels of application of clock gating are evaluated, including a novel multi level solution. Besides assessing the benefits and drawbacks of the clock gating application at different levels, hints for future design automation of low power reconfigurable accelerators through high level synthesis are also derived.

scholarly journals Application of an Artificial Neural Network to Automate the Measurement of Kinematic Characteristics of Punches in Boxing

2021 ◽  
Vol 11 (3) ◽  
pp. 1223
Author(s):  
Ilshat Khasanshin
Keyword(s):  
Neural Network ◽  
Artificial Neural Network ◽  
Kinematic Parameters ◽  
Constant Control ◽  
Measurement Units ◽  
Artificial Neural ◽  
Artificial Neural Network Ann ◽  
Effective Development ◽  
High Level ◽  
Different Levels

This work aimed to study the automation of measuring the speed of punches of boxers during shadow boxing using inertial measurement units (IMUs) based on an artificial neural network (ANN). In boxing, for the effective development of an athlete, constant control of the punch speed is required. However, even when using modern means of measuring kinematic parameters, it is necessary to record the circumstances under which the punch was performed: The type of punch (jab, cross, hook, or uppercut) and the type of activity (shadow boxing, single punch, or series of punches). Therefore, to eliminate errors and accelerate the process, that is, automate measurements, the use of an ANN in the form of a multilayer perceptron (MLP) is proposed. During the experiments, IMUs were installed on the boxers’ wrists. The input parameters of the ANN were the absolute acceleration and angular velocity. The experiment was conducted for three groups of boxers with different levels of training. The developed model showed a high level of punch recognition for all groups, and it can be concluded that the use of the ANN significantly accelerates the collection of data on the kinetic characteristics of boxers’ punches and allows this process to be automated.

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