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This paper presents the optimization of the design of a railway wheel in terms of the wheel's sound power levels emission, with respect to its geometrical properties. To this end, a simplified finite element method (FEM) model of the wheel was employed, that did not include the interaction of the wheel and rail or the influence of the braking system that is assembled on the wheel. The objective of the optimization method was to find a design of the selected railway wheel, which without the use of damping or tuning devices, emits less vibration/noise compared to the original design. The optimization method used, was based on genetic algorithms (GAs). GAs are a robust optimization method that performs regardless of the optimization problem. The GA‐based optimization method that is presented in this paper, utilized ANSYS running in batch mode for the calculation of the objective function values of the population of each generation.

The purpose of the study is to present a frequency domain spectral finite element model (SFEM) based on fast Fourier transform (FFT) for wave propagation analysis of smart laminated composite beams with embedded delamination. For generating and sensing high-frequency elastic waves in composite beams, piezoelectric materials such as lead zirconate titanate (PZT) are used because they can act as both actuators and sensors. The present model is used to investigate the effects of parametric variation of delamination configuration on the propagation of fundamental anti-symmetric wave mode in piezoelectric composite beams.

The spectral element is derived from the exact solution of the governing equation of motion in frequency domain, obtained through fast Fourier transformation of the time domain equation. The beam is divided into two sublaminates (delamination region) and two base laminates (integral regions). The delamination region is modeled by assuming constant and continuous cross-sectional rotation at the interfaces between the base laminate and sublaminates. The governing differential equation of motion for delaminated composite beam with piezoelectric lamina is obtained using Hamilton’s principle by introducing an electrical potential function.

A detailed study of the wave response at the sensor shows that the A0 mode can be used for delamination detection in a wide region and is more suitable for detecting small delamination. It is observed that the amplitude and time of arrival of the reflected A0 wave from a delamination are strongly dependent on the size, position of the delamination and the stacking sequence. The degraded material properties because of the loss of stiffness and density in damaged area differently alter the S0 and A0 wave response and the group speed. The present method provides a potential technique for researchers to accurately model delaminations in piezoelectric composite beam structures. The delamination position can be identified if the time of flight of a reflected wave from delamination and the wave propagation speed of A0 (or S0) mode is known.

Spectral finite element modeling of delaminated composite beams with piezoelectric layers has not been reported in the literature yet. The spectral element developed is validated by comparing the present results with those available in the literature. The spectral element developed is then used to investigate the wave propagation characteristics and interaction with delamination in the piezoelectric composite beam.

The progressive increase in the size of datasets has given life to the so-called big data that provides researchers with the opportunity to extract a greater amount of useful information in many sectors, especially in the tourism industry.

The chapter aims to demonstrate that sustainable tourism (ST) could be particularly favored by using big data and a data-driven approach. Furthermore, as ST appears in line with a new type of responsible entrepreneurship, called Humane Entrepreneurship (HumEnt), this chapter investigates the link between ST and HumEnt and the impact of big data and data-oriented approaches on ST and HumEnt.

The research adopts a qualitative approach, applying the case study technique. The authors conducted ten semi-structured interviews with key informants from a specific form of hospitality: Albergo Diffuso. Findings show the advantages of the data-driven approach to tourism and entrepreneurship highlighting how using data creates new opportunities for decision making in ST and HumEnt.

The purpose of this paper is to first integrate incorporated commitment, self-identity, and moral responsibility with the theory of planned behaviour (TPB) to predict the green food and beverage (GFB) behaviours in protecting food environment. Moreover, this study also identified the key influential factors of green behaviours and analysed the mediation effects of commitment in this extended TPB model.

The structural equation modelling based on 793 college students was used to verified the goodness-of-fit and direct effects of the extended TPB model of GFBs, and bootstrap method was also used to examine the indirect effects.

The results of this study revealed commitment, perceived behavioural control (PBC), and perceived knowledge of GFBs were the most influential factors of GFBs. Furthermore, this study also verify that PBC influences civic behaviour pertaining to GFBs, and commitment mediated the effects of subjective social norms between PBC and GFBs.

This study provided value for GFBs that prompting people to exhibit civic behaviour pertaining and commitment to GFBs as well as ensuring environmentally sustainable development of GFBs.

The aim of the study was to compare the nutritional status of children having celiac disease (CD) with those not having the disease in the age group of 7-12 years. Children not having CD were from first- and second-degree siblings of the children affected to match for family and environment. In Indian celiac pediatric population, studies on nutritional status of celiac children and comparisons with their siblings as reference have not been reported.

Children with CD (n = 50) and without CD (n = 25) were matched for age and were purposively selected. Nutritional assessment included anthropometry, biochemical, clinical and nutrient intake. Weight and height measurements were recorded as per the standardized techniques. Biochemical investigations were done by skilled technicians. A two-day 24-h dietary recall method was used for calculation of nutrient intake. The observations were categorized as celiac and non-celiac children and pre-adolescents in age group of 7-9 years and 10-12 years.

The issues of being underweight and of low height according to age among celiac children were rampant. The non-celiac children were comparatively taller than children with CD. The hemoglobin and serum iron were significantly lower in celiac than non-celiac group (p < 0.01). Energy intake was significantly higher (p < 0.05) in celiac pre-adolescents as compared to non-celiac children (7-9 years). The protein intake was higher in non-celiac children, and the difference was highly significant (p < 0.01). The fat consumption was higher in celiac pre-adolescents. The nutritional status of celiac children was poor as compared to non-celiac children.

The present study is an attempt to compare the nutritional status of celiac children with their siblings.

The purpose of this paper is to provide a comprehensive summary of the effect of different dietary approaches on polycystic ovary syndrome (PCOS).

This review represents the history of PCOS, the symptoms, diagnosis, and treatment. It also includes up‐to‐date research articles on different types of diets that have been shown some promising effects in the treatment of PCOS.

PCOS is nowadays considered the most common endocrine abnormality, with a range of 4‐12 per cent of women affected by the syndrome. It has been proven that diet, in addition to exercise and medication, plays an important role in the treatment of PCOS. The proper dietary approach for women with PCOS should focus on the PCOS symptoms and also improve weight loss, increase fertility, and decrease risks of cardiovascular diseases.

This paper provides accessible and comprehensive information on PCOS (since its discovery in 1935) to researchers, nutritionists, and women with PCOS who are interested in the effect of the diet on PCOS management.

Technical education plays an important role in the development of a country in this age of knowledge economy. Indian technical education system is facing many opportunities and challenges, one of which is how to assess the performance of technical institutions based on multiple criteria. The purpose of this paper is to describe and illustrate an application of a structured approach to determine relative efficiency and ranking of a set of private engineering colleges under multi-criteria environment.

To cater to the increasing need of technical manpower, a very large number of private engineering colleges have been established in the state of West Bengal of eastern India within a very short period. Uniform and acceptable quality of the graduates from many of these private engineering colleges is a concern today and therefore the need for performance evaluation and ranking of these colleges is paramount. For the proposed framework a comparatively new multiple criteria decision-making tool, multiple objective optimization on the basis of simple ratio analysis (MOOSRA) is applied for performance evaluation of eight private engineering colleges taking into account some selected criteria. The subjective weights of the criteria are determined using fuzzy analytic hierarchy process (AHP).

For the analysis, the required data have been provided by the management of the colleges for the academic year of 2011-2012. Based on request of the management identities of these institutes are not disclosed. The institutes are considered as anonymous institute and coded as A, B, C, D, E, F, G and H, respectively. The result of the study reveals that E is the best and the ranking the authors get is in the order of E > F > A > H > D > C > G > B. The result shows that composite performance scores of institutions A, E and F are above the mean performance score value. Therefore these three institutions can be considered as the benchmark or peer group for the remaining five institutions which lie below the mean line of the performance score value.

This paper provides a comprehensive yet detailed methodology for performance evaluation of academic institutions. The novelty in the approach is that fuzzy AHP and MOOSRA are being used as a benchmarking technique in a simple methodology which is generic in nature. It is one of the few studies that evaluate the performance of technical institutions in India.

This paper aims to present a novel robotic system for airport pavement inspection tasks.

The cloud-edge-terminal-based distributed architecture is designed for the proposed robotic system. Then, the following three major parts are designed and deployed, respectively: Terminal: the wheeled-robot-based data collection system. Edge: remote monitoring and data analysis system. Cloud: shared database center of the inspection data and knowledge.

Validation and application results show that the proposed system satisfies the demands of automated airport pavement inspection tasks and saves the cost of manpower and time.

The proposed system provides a novel solution for the full process of airport pavement inspection. Compared with the traditional manual method, the robotic system can guarantee complete coverage and provide high-precision pavement inspection results with less time and labor costs.

The purpose of this paper is to introduce a new numerical approach for studying a cantilever bar having a transverse crack. The crack is modeled by an elastic longitudinal spring with a stiffness K according to Castiglione’s theorem.

The bar is excited by different longitudinal impulse forces. The considered problem based on the differential equation of motion is solved by the method of characteristics (MOC) after splitting the second-order motion equation into two first-order equivalent equations.

In this study, effects of the crack size and crack’s position on the reflected waves from the crack are investigated. The results indicate that the presence of the crack in the cantilever bar generates additional waves caused by the reflection of the incident wave by the crack.

A numerical approach developed in this paper is used for detecting the extent of the damage in cracked bars by the measurement of the difference between the dynamic response of an uncracked bar and a cracked bar.