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In the present paper a weighted residual formulation of wave propagation through a porous material for a three‐dimensional case, based on the theoretical formulation of Zwikker and Kosten for sound propagation in porous material, is described. Based on this formulation, a MATLAB code was developed which simulates an experimental configuration that consists of: a double wall cavity, formed by two parallel aluminum panels; and a reverberation room. A loudspeaker is placed on the reverberation room to provide the acoustical excitation of the double wall set‐up. The results which are obtained from the MATLAB code, in terms of the sound pressure level (SPL) in the double wall cavity and the displacement of the two panels, are compared with the corresponding experimental ones for the cases of air and thermal insulation material being the medium filling the double wall cavity.

The purpose of this paper is to classify different conditions of the rolling element bearing (REB) using vibration signals acquired from a customized bearing test rig.

An effort has been made to develop health index (HI) based on singular values of the statistical features to classify different conditions of the REB. The vibration signals from the normal bearing (N), bearing with defect on ball (B), bearing with defect on inner race (IR) and bearing with defect on outer race (OR) have been acquired from a customized bearing test rig under variable load and speed conditions. These signals were subjected to “modified kurtosis hybrid thresholding rule” (MKHTR)-based denoising. The denoised signals were decomposed using discrete wavelet transform. A total of 17 statistical features have been extracted from the wavelet coefficients of the decomposed signal.

Singular values of the statistical features can be effectively used for REB classification.

REB are critical components of rotary machinery right across the industrial sectors. It is a well-known fact that critical bearing failures causes major breakdowns resulting in untold and most expensive downtimes that should be avoided at all costs. Hence, intelligently based bearing failure diagnosis and prognosis should be an integral part of the asset maintenance and management activity in any industry using rotary machines.

It is found that singular values of the statistical features exhibit a constant value and accordingly can be assigned to each type of bearing fault and can be used for fault characterization in practical applications. The effectiveness of this index has been established by applying this to data from Case Western Reserve University data base which is a standard bench mark data for this application. HIs minimizes the computation time when compared to fault diagnosis using soft computing techniques.

Lignite coal-fired power plants are the main electricity generators in the province of Saskatchewan, Canada. Although burning lignite coal to generate power is economical, it produces significant greenhouse gases making it a big challenge to Canada’s international commitment on emission reduction. However, abundant agricultural crops and sawdust produced in Saskatchewan put the province in a good position to produce and use agri-pellets as an alternative fuel to generate electricity. This study aims to conduct an economic and environmental analysis of the replacement of lignite coal by agri-pellets as the fuel for Saskatchewan’s coal-fired power plants.

The study estimates the economic and environmental costs and benefits of two alternative fuels for power plants. The economic analysis is based on the pellet production and transportation costs from farms to production sites and from the production sites to power plants. In the production process, biomass precursors are densified with and without additives to produce fuel agri-pellets with appropriate mechanical durability and high heating value per volume unit. The environmental analysis involves estimation of greenhouse gas emissions and their social costs for lignite coal and different types of agri-pellets under different scenarios for pellet production and transportation.

The results show that although the total cost of electricity is lower for coal than agri-pellets, the gap shrinks when social costs and specifically a carbon price of $50/tonne are included in the model. The cost of electricity in lignite coal-fired power plants would also be on par with agri-pellets-fired power plants if the carbon price is between U$68 and $78 per tonne depending on the power plant locations. Therefore, a transition from coal to agri-pellet fuels is feasible if a high-enough price is assigned to carbon. The method and the results can be generalized to other places with similar conditions.

There are a few caveats in this study as follows. First, the fixed costs associated with the transformation of the existing coal-fired power plants to pellet-fired plants are not considered. Second, the technological progress in the transportation sector, which would favor the net benefits of using pellets versus coal, is not included in the analysis. Finally, the study does not address the possible political challenges facing the transition in the context of the Canadian federal system.

The study results indicate that the current carbon price of $50 per tonne is not sufficient to make the agri-pellets a feasible source of alternative energy in Saskatchewan. However, if carbon pricing continues to rise by $15 annually starting in 2022, as announced, a transition from coal to agri-pellets will be economically feasible.

Canada is committed to reduce its emission according to the Paris agreement, and therefore, needs to have a concrete policy to find alternative energy sources for its coal-fired power plants. This study examines the challenges and benefits of such transition using the existing agri-pellet resources in Saskatchewan, a province with abundant agricultural residues and coal-fired power plants. The findings indicate that a significant emission reduction can be achieved by using agri-pellets instead of coal to produce electricity. The study also implies that the transition to renewable energy is economical when social costs of carbon (carbon tax) is included in the analysis.

As far as the authors know, this is the first study providing a socio-economic analysis for a possible transition from the coal-fired power plants to a more clean and sustainable renewable energy source in one of the highest carbon dioxide (CO₂) producer provinces in Canada: Saskatchewan. The study builds upon the technical production of three agri-pellets (oat hull, canola hull and sawdust) and estimates the economic and environmental costs of alternative fuels under different scenarios.

Active noise control (ANC) became in the last decade a very popular technique for controlling low‐frequency noise. The increase in its popularity was a consequence of the rapid development in the fields of computers in general, and more specifically in digital signal processing boards. ANC systems are application specific and therefore they should be optimally designed for each application. Even though the physical background of the ANC systems is well‐known and understood, tools for the optimization of the sensor and actuator configurations of the ANC system based on classical optimization methods do not perform as required. This is due to the nature of the problem that allows the calculation of the effect of the ANC system only when the sensor and actuator configurations are specified. An additional difficulty in this problem is that the sensor and the actuator configurations cannot be optimized independently, since the effect of the ANC system is directly involved in the combined sensor and actuator configuration. For the solution of this problem several intelligent techniques were applied. In this paper the successful application of a genetic algorithm, an optimization technique that belongs to the broad class of evolutionary algorithms, is presented.

In recent years, the use of mobile devices for academic persistence has grown to be an indispensable element of students’ learning, highlighting the broad acceptance and adaptability of mobile technology in learning environments. The current study examines how college students in rural areas use mobile devices and how self-efficacious they are when seeking online information. Additionally, the study investigated the connection between mobile devices usage (MDU), mobile devices self-efficacy (MDSE) and online information seeking behavior (OISB) on the basis of demographic differences.

A quantitative research design was used by deploying a five-point Likert scale for measurement, Statistical Package for Social Sciences (SPSS) v.26 was used for data analysis. A variety of statistical methodologies, including t-tests, ANOVA and correlation coefficients, were conducted to inspect and assess MDU, MDSE and OISB across gender and age groups. Data from 331 students at the public sector college in a rural region was gathered using a questionnaire. A total of 315 legitimate replies were received.

The study's conclusions showed that the respondents used their mobile devices for educational purposes less frequently. Nonetheless, the respondents' degrees of MDSE and OISB appear to be high. Furthermore, a strong link was demonstrated among the MDU, MDSE and OISB. On the contrary, there was a negative correlation link between MDU and both MDSE & OISB, while a positive correlation between MDSE and OISB was found. The results also showed substantial variance in all research components based on age and gender, indicating that male and younger respondents performed more efficiently than female and adult respondents.

These results indicate that information literacy guidelines and a variety of educational initiatives should be put together by the government, educational policymakers, librarians and educators, with a focus on how to use mobile devices for learning and information seeking. This will make it possible for students to more efficiently find the information using their portable devices.

This study explored preservice and in-service early childhood teachers' online academic learning beliefs and strategies.

Two hundred preservice and in-service teachers respectively from Taiwan participated in this research. A focus group discussion was carried out concerning the development of the questionnaires. The exploratory and confirmatory factor analysis confirmed good construct validity and reliabilities of the survey.

The survey results showed that in-service teachers generally held more sophisticated learning beliefs than the preservice teachers in all scales. Also, in-service teachers responded with a higher level of online academic learning strategies than the preservice teachers did. Regarding their online experiences, preservice teachers who spent an appropriate amount of time online had more positive beliefs than those with excessive online experiences. However, preservice teachers did not reveal employment of their ICT literacy in their online academic learning strategies. It was found that those in-service teachers with more online learning experience also showed higher levels of online academic learning beliefs. They used more deep strategies in their online academic learning.

The findings of this study could provide insights for the development of online academic learning ability in preschool teacher training programs.

(1) In-service teachers generally held more sophisticated learning beliefs than the preservice teachers. (2) Preservice teachers who spent an appropriate amount of time online had more positive beliefs than those with excessive online experiences. (3) Preservice teachers did not reveal employment of their ICT literacy in their online academic learning strategies. (4) In-service teachers with more online learning experience also showed higher levels of online academic learning beliefs. They used more deep strategies in their online academic learning.

The development of health literacy skills is of paramount importance especially for students, as it is associated with their wellbeing and academic success. Assessing students' health literacy is necessary for its advancement. This study comes to fill the need for a valid multidimensional health literacy assessment instrument for secondary school students.

Initially, the authors defined the conceptual framework within which the items of this instrument were generated. Its final form was obtained through three pilot studies. A test-retest followed and, finally, a nationwide survey was conducted on Greek seventh-, ninth- and tenth-grade students (N = 2,800).

A 37-item instrument, the Health Literacy Assessment for Secondary School Students (HeLiASeSS), was developed which includes the following nine dimensions/skills of health literacy: “access to”, “understand” and “evaluate” (health information), “functional communication”, “interactive communication” and “critical communication”, “relying on health information”, “self-efficacy regarding health matters” and “intention for active citizenship regarding health matters”. HeLiASeSS proved to have good stability (ICC = 0.943) and high internal consistency reliability (a = 0.903).

HeLiASeSS offers the possibility of a reliable and valid assessment of secondary school students' health literacy skills providing a multidimensional evaluation of this construct and is expected to be useful in interventions aiming at promoting this type of literacy.

The research objectives are to interview rising preschool teachers studying at Russian universities, highlight the categories of information technologies used in preschool institutions based on the survey results and possible difficulties that may arise when working with them and develop tips for working with interactive technologies for preschool teachers.

The results of the survey showed a high level of involvement of information technology in the educational process. The majority of respondents (87%) use information technology in teaching and learning. The analysis of the answers shows relatively identical indicators of the use of different types of information technologies: 65% prefer more technological and 35% – applied. It was shown that the use of technological and applied ICT categories isn't similar among participants of the survey. To increase the level of students' and teachers’ knowledge with modern information technologies the program was created.

In preschool education, the kindergarten teacher or supervisor should act as the leader of the learning process, including the interactive one. The teacher should encourage children to independently use the ICT tools and guide the process.

Given the rapid pace of development of science and technology, the curriculum needs to be deepened and expanded by diversifying activities. It is worth paying attention to modern methods of teaching and learning, which require the use of pedagogical innovations, the acquaintance of students and teachers with possible ways to expand the activities and update the latest teaching methods in educational process.

Discusses the authors’ approach to experiential learning in a two‐semester “engineering physics” course at a large metropolitan university in the USA. A student‐centered methodology stressing teamwork while incorporating individual creativity is used in an interdisciplinary course setting. Students practice transferable skills relevant to today’s technological workplace. Discusses the methodology and lessons learned in the context of higher education in the USA and abroad.

The purpose of this study is to demonstrate the importance and influence of paternity leave on individual level organizational outcomes. Drawing on signaling theory, the study examines the relationship between paid paternity leave entitlement (PPLE) and organizational attractiveness (OA) through a mediating path of anticipated organizational support (AOS). Furthermore, the study proposes that this mediated relationship would be conditional on traditional masculinity ideology (TMI) such that the relationship would be stronger for individuals who score low on TMI.

The study analyzed a moderated mediation model using the data from a survey experiment. Data were collected from 264 professionals enrolled in an executive education course and will soon be looking for employment.

The findings supported the mediating role of AOS between PPLE and OA. As predicted, the positive impact of PPLE on AOS and OA is stronger for individuals scoring low on TMI.

This study takes a multidisciplinary approach to understand the underlying mechanisms that impact decisions related to employers. It is one of the few studies that study paternity leave in the Indian context and makes important contributions to theory and practice.