Modeling the systematic behavior at the micro and nano length scales

The assessment of the systematic behavior based on frequentist statistics was analyzed in the context of micro/nano metrology. The proposed method is in agreement with the well-known GUM recommendations. The investigation assessed three different case studies with definition of model equations and establishment of the traceability. The systematic behavior was modeled in Sq roughness parameters and step height measurements obtained from different types of optical microscopes, and in comparison with a calibrated contact instrument. The sequence of case studies demonstrated the applicability of the method to micrographs when their elements are averaged. Moreover, a number of influence factors, which are typical causes of inaccuracy at the micro and nano length scales, were analyzed in relation to the correction of the systematic behavior, viz. the amount of repeated measurements, the time sequence of the acquired micrographs and the instrument-operator chain. The possibility of applying the method individually to the elements of the micrographs was instead proven not convenient and too onerous for the industry. Eventually, the method was also examined against the framework of the metrological characteristics defined in ISO 25178-600 with hints on possible future developments.

Research on Influence Factors of Bearing Capacity of Concrete-Filled Steel Tubular Arch for Traffic Tunnel

When a traffic tunnel passes through special strata such as soft rock with high geo-stress, expansive rock, and fault fracture zones, the traditional supporting structure is often destroyed due to complicated loads, which threatens the construction and operation safety of tunnel engineering. Concrete-filled steel tubular (CFST) structure gives full play to the respective advantages of steel and concrete and has better bearing capacity and economic benefits than traditional support structure, which has achieved good results in some underground engineering applications. In order to promote the application of CFST in the construction of traffic tunnels with complex geological conditions and improve the bearing capacity of the initial supporting structure of tunnels, the influencing factors of the bearing capacity of CFST arch were studied by numerical simulation. The main achievements are as follows: (1) The load-displacement curves of CFST members under different material parameters are basically consistent. CFST members have significant restrictions on displacement in the elastic stage and have high ultimate bearing capacity. Although the bearing capacity decreases obviously after reaching the peak, it shows good extension performance. (2) The height of the steel tube section, the thickness of the steel tube wall and the grade of the core concrete have an approximately linear positive correlation with the bearing capacity of CFST arch, but the influence of these three factors on the bearing capacity of CFST arch decreases in turn, and when the grade of core concrete increases above C50, it has no significant effect on the bearing capacity of members.

Why Not STEM? A Study Case on the Influence of Gender Factors on Students’ Higher Education Choice

The gender gap in STEM-related job positions is a fact, and it is closely related to the low percentage of women studying STEM degrees. This poses a problem because Europe, as well as the United States and the rest of the developed countries, keep demanding the best engineers and scientists to continue developing innovative products. This problem can thus be approached by answering, firstly, the following question: Why are women not studying STEM degrees? In this paper, we summarize the factors, found in literature, that influence students—both boys and girls—to not study STEM, particularly engineering, computer sciences and technology. We study these influence factors in a sample of N = 338 students from a secondary school placed in the south of Spain; we carry out a survey in order to find out if those students fill out the same answers other researchers have found and published in the related literature. Our main conclusions are as follows: The results confirm that the number of women in technical courses decreases when the level of the course increases; the lack of role models is not an impediment for girls to feel comfortable; unlike boys, girls will not choose engineering, even if their scoring in STEM is good; and we found that girls and women see themselves as not capable of studying an engineering degree more than boys and men do. These results contribute to a deeper understanding of the situation regarding the gender gap in STEM fields in ages in which both girls and boys must choose their future studies.

Effect of Protein Nutrition Level on Protein Metabolism during Volleyball Exercise Based on Edge Computing in the Medical System

With the rapid development of the Internet of Things, 5G, and communication technologies, the growth of various types of data has shown an exponential trend. Edge computing technology provides users with almost unlimited computing power through a large number of high-performance servers in the data center. It is one of the important solutions for big data analysis and processing. Volleyball has caused a great wave in China as early as the 1960s, but people pay little attention to the physical quality of volleyball players. At the same time, in the medical field, it is difficult to give a clear value to the athlete’s protein requirement. Therefore, this article aims to observe the specific values of protein metabolism in volleyball at different levels of protein nutrition. By designing controlled experiments, then these rats under three nutrient levels of protein were observed and protein metabolism was analyzed after volleyball. The results of the study show that volleyball exercise can reduce the nitrogen balance and gastrocnemius nitrogen content. The nitrogen balance of the 17% group decreased from 388 mg/day before exercise to 336 mg/day, and the gastrocnemius nitrogen content decreased by up to 5.2%; serum urea nitrogen concentration and liver nitrogen content are increased, indicating the enhancement of protein catabolism. Different protein nutrition levels have different effects on protein metabolism during volleyball. The protein intake level of 17% is more conducive to resist the protein decomposition caused by volleyball. It can be seen that, based on edge computing technology, the influence factors of protein nutrition level on protein metabolism during volleyball sports can be well explored, and the research results are also very valuable.

Joint Analysis and Reliability Test of Epoxy-Based Nano Silver Paste Under Different Pressure-Less Sintering Processes

Recent years, the sintered silver paste was introduced and further developed for power electronics packaging due to low processing temperature and high working temperature. The pressure-less sintering technology reduces the stress damage caused by the pressure to the chip, improves reliability, and is widely applied in manufacturing. Currently, most existed studies are focused on alcohol-based sintered silver pastes while resins have been demonstrated to improve the bonding properties of solder joints. Hence, the performance and sintering mechanisms with epoxy-based silver paste need to be further explored. In this work, a methodology for multi-factor investigation is settled on the epoxy-based silver paste to reveal the relationship between the strength and the different influence factors. We firstly analyzed the characteristics of commercialized epoxy-based silver paste samples, including silver content, silver particle size, organic paste composition, sample viscosity, and thermal conductivity. Samples were then prepared for shear tests and microstructure analysis under different pressure-less sintering temperatures, holding time, substrate surface, and chip size. Full factor analysis results were further discussed in detail for correlation. The influence factors were ranked from strong to weak as follows: sintering temperature, substrate surface, chip size, and holding time. Finally, a thermal cycling test was carried out for reliability analysis. Epoxy residues are one of the possible reasons which result in shear strength decreasing exponentially.

Effectiveness and Practicality of eKTANG as a Digital Treat-ment for Diabetes and Relevant Influence Factors

Background: This work explored the effect of eKTANG, a new healthcare mode for diabetes patients, on diabetes management. Methods: Allowing general utilization of medical service and health management based on Internet, eKTANG obtained the precise data like blood glucose and blood pressure examined by an intelligent glucometer, from which doctors and the nursing team will promptly analyze the data and return feedback to the patients. In our study, overall 204 patients receiving eKTANG management over 3 months in First Affiliated Hospital of Jinan University from May 2019 to Aug 2020 were enrolled as the research objects, with data collected from patient records. Results: Through the biochemical test on relevant indexes of blood glucose, it was observed that FBG, PBG, HbA1c, TG, TC, LDL levels after management were lower than before whereas HDL expression after were lower than before. Contrasted with substandard group, standard group performed younger age, lower proportion of the married, decreased proportion of microvascular and macrovascular complications, longer course of disease, more frequent glucose monitoring, declined time of hyperglycemia and time of alarms, elevated time of euglycemia, increased proportion of diet control, more amount of exercise and higher compliance, as the number of patients choosing oral medicine in standard group was more than substandard group. The course of disease and time of hyperglycemia were risk factors of HbA1c standard reaching whereas frequency of glucose monitoring (≥1 time/week) and time of euglycemia were protective factors. Conclusion: eKTANG effectively improved diabetes management.

Modeling and Simulation of Consumer Preference Decision for Commercial Complex Location Based on System Dynamics

The influencing factors of consumer shopping behavior play a key role in the later performance of commercial real estate enterprises. On the basis of analyzing the influence factors of customer patronage and the influence factors of commercial complex site selection decision and their relationship, a causal relationship graph and a system dynamic model are established, which can describe the influence of customer preference on commercial complex site selection decision. And introducing customer subjective factors optimize the original pure objective factors site selection decision model. The model is implemented by using the system dynamics modeling tool Vensim. At the same time, the model is verified by using the data of the first-hand investigation. The results show that the calculated data of the model is in good agreement with the actual data. The results show that the system dynamics method can effectively simulate the influence of various factors on the decision-making of the commercial complex. As the forecast of the model, the key indexes of the decision-making of the city commercial complex are discussed, and the measures to be taken are put forward, which can provide reference for the decision-making of the location.

Development of Broadband Resistive–Capacitive Parallel–Connection Voltage Divider for Transient Voltage Monitoring

The on-site measurement of transient voltages is of great significance in analyzing the fault cause of power systems and optimizing the insulation coordination of power equipment. Conventional voltage transformers normally have a narrow bandwidth and are unable to accurately measure various transient voltages in power systems. In this paper, a wideband parallel resistive–capacitive voltage divider is developed, which can be used for online monitoring of transient voltages in a 220 kV power grid. The structures of the high-voltage and low-voltage arms were designed. The internal electric field distribution of the high-voltage arm was analyzed. The influence factors and improvement techniques of the upper frequency limit were studied. The parameters of the elements of the divider were determined. The voltage withstand performances and scale factors under lightning impulses and AC and DC voltages, the temperature stabilities of scale factors and the step response and bandwidth of the developed voltage divider were tested. The results show that the deviations of the scale factors under various voltage waveforms and different temperatures ranging from −20 to 40 °C are within 3%. The withstand voltage meets the relevant requirements specified in IEC60071-1-2011. The step response 10~90% rise time is approximately 29 ns, and the 3 dB bandwidth covers the range of DC to 10 MHz.

Trajectories of subject-interests development and influence factors in higher education

It is a well-studied phenomenon, that throughout the course of studying at university, the motivation for the study program decreases. Correlation between motivation and learners’ behaviour, for example the learning process, achievement or, in the worst case, dropout exist. So there is a need for understanding the development of motivation in detail, like that of subject-interests, and for identifying influence factors, especially for higher education. This panel study examined the development of 4,345 students in higher education. Growth mixture models for subject-interests identify two classes of trajectories: “descending interest” and “continuously high interest”. In a next step, the analysis shows that gender, university entrance score, academic field and occupational aspiration influence membership of the classes. The results are discussed with respect to their consequences for education programs, but also with respect to possible new research questions.