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1 – 10 of 98M.J.P. William‐Louis and C. Tournier
Describes the propagation of pressure waves when a train passes through a plain tunnel or tunnel equipped with side branches. A non‐homentropic one‐dimensional model is used to…
Abstract
Describes the propagation of pressure waves when a train passes through a plain tunnel or tunnel equipped with side branches. A non‐homentropic one‐dimensional model is used to predict the flow generated. This model takes into consideration the train and tunnel geometry, the wall friction and heat transfer. The numerical calculation is performed using the classical method of characteristics. Near the train and tunnel ends, or at the junctions with the side branches, the flow is three dimensional. In the one‐dimensional theory, boundary conditions are applied to model the flows across these regions. The model used is validated by comparisons with experimental results. The use of airshafts to attenuate pressure waves is discussed.
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Kamel Ettaieb, Kevin Godineau, Sylvain Lavernhe and Christophe Tournier
In Laser Power Bed Fusion (LPBF), the process and operating parameters influence the mechanical and geometrical characteristics of the manufactured parts. Therefore, the…
Abstract
Purpose
In Laser Power Bed Fusion (LPBF), the process and operating parameters influence the mechanical and geometrical characteristics of the manufactured parts. Therefore, the optimization and control of these parameters are mandatory to improve the quality of the produced parts. During manufacturing, the process parameters are usually constant whatever the part size or the built layer. With such settings, the manufacturing process may lead to an inhomogeneous thermal behavior and locally overheating areas, impacting the part quality. The aim of this study is to take advantage of an analytical thermal model to modulate the laser power upstream of manufacturing.
Design/methodology/approach
The approach takes place in two steps: the first step consists in calculating the preheating temperature at the considered point and the second one determines the power modulation of the laser to reach the desired temperature at this point.
Findings
Numerical investigations on several use cases show the effectiveness of the method to control the overheated areas and to homogenize the simulated temperature distribution.
Originality/value
The specificity of this model lies in its ability to directly calculate the amount of energy to be supplied without any iterative calculation. Furthermore, to be as close as possible to the technology used on LPBF machines, the kinematic behavior of the scanning head and the laser response time are also integrated into the calculation.
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One of the most significant impacts of the withdrawal of the United Kingdom from the European Union (EU) would be the complication, and even the stalemate, of the supranational…
Abstract
One of the most significant impacts of the withdrawal of the United Kingdom from the European Union (EU) would be the complication, and even the stalemate, of the supranational unification process of the EU, which was the founding idea of the Union. In this chapter, the adverse circumstances that will take place in the supranational unification process will be addressed over two significant issues. The first of the issues is the losses that the Union will experience. The Union, which had realized partnership in many areas to achieve the supranational unification and which, at least, has held out hope for other areas, would experience significant losses concerning motivation, time, capacity, and power of influence, and it would be difficult for the Union to reconstitute itself. In addition to these losses, the consolidation of the right-wing populism filled with Eurosceptic and nationalist reactions in the member states following Brexit will further weaken the aspiration for supranational unification. Ultimately, the visibility of the relations in an intergovernmental context, instead of a supranational one, will become the dominant element, and the EU's journey toward long-term founding purpose will receive a major blow.
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Teacher professional development is a perennial topic in teaching and teacher education. While it is largely agreed that the professional development of teachers is a necessity…
Abstract
Teacher professional development is a perennial topic in teaching and teacher education. While it is largely agreed that the professional development of teachers is a necessity, what that professional development entails and who decides its content and delivery is disputed. This chapter revisits critical issues in the professional development of teachers. Different forms of professional learning, the influence of collaboration, the pursuit of inclusion and social justice, and the role of technology are discussed. In the future, it is expected that professional development contexts and opportunities will be reimagined along with a new calibration of face-to-face and virtual pedagogies.
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Yi Jing Thun, See Wan Yan, Chin Ping Tan, Wen Xin Teoh and Xin Yue Gan
Prevention of chronic diseases by means of dietary modification can be achieved by consuming healthier foods with lower sugar content. However, reducing sugar content causes…
Abstract
Purpose
Prevention of chronic diseases by means of dietary modification can be achieved by consuming healthier foods with lower sugar content. However, reducing sugar content causes significant impact on the sensory quality and consumers’ acceptance towards local healthy products. This study aims to evaluate the effects of cross-modal interactions of Aroma-Taste-Texture (ATT) in yoghurt drink.
Design/methodology/approach
Fifteen sugar reduced yoghurt drinks [S, sugar percentage (0%, 2%, 4%); T, stevia dosage (0%, 0.01%, 0.02%); P, pectin dosage (0%, 0.3%, 0.6%)] based on ATT were evaluated by 300 consumer panellists on aroma, taste, texture and overall acceptability on a nine-point hedonic scale while sweetness intensity was measured using a seven-point just-about-right (JAR) scale. Interactions between ATT were determined.
Findings
Significant interaction was found between sugar and stevia, with F14 (4S0.02T0P) rated as sweeter than F4 (0S0.02T0P) (p = 0.003) and higher overall liking score than F11 (4S0T0P) (p = 0.001). Similarly, significant interaction was found between sugar and pectin, with F2 (0S0T0.6P) rated as significantly lower overall liking score and less sweet than F1 (0S0T0P) (p = 0.0001). Likewise, significant interaction was found between stevia and pectin, with F2 (0S0T0.6P) rated as significantly lower overall liking score and less sweet than F1 (0S0T0P) (p = 0.0001). Overall, F5 (0S0.02T0.6P) scored highest in overall liking and closest to the ideal sweetness (JAR = 4) indicating the possibility to apply 100% sugar replacement.
Originality/value
Application from the present study could be great potential solution in developing healthier range products while meeting consumer preference. The present study concluded that interactions of ATT of yoghurt drink will induce desirable changes in sensory and sweetness perception.
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Mahsa Mohajeri, Shiva Hoojeghani, Azimeh Izadi, Mohammad Ghahremanzadeh, Farhad Pourfarzi, Ali Nemati and Ali Barzegar
This study aims to investigate the food choice motivations and some healthy food intake among Ardabil adults with different socioeconomic status.
Abstract
Purpose
This study aims to investigate the food choice motivations and some healthy food intake among Ardabil adults with different socioeconomic status.
Design/methodology/approach
The analysis is based on a focus group study conducted in September 2018. Self-assessed other food choice motivations, healthy food intake and socioeconomic status were reported in questionnaires. The study data were analyzed by one-way ANOVA test and χ2 test in groups of study.
Findings
Price was a primary motivation of food choice for low-level socioeconomic status persons. The wealthiest people total vegetable consumption was 3.59Â ± 0.004 serving/day, whereas the total vegetable consumption of poorest participants was significantly less than them (p = 0.012). Of the socioeconomics category 1 (SEC1) group participants, 82 per cent said that they consider food price when they were purchasing for their households, while only 28 per cent of SEC4 group said that they consider food prices when food choosing. Only 1 per cent of this group participants pay attention to food label when they choose foods.
Originality/value
This is the first study that investigated the food choice motivations in Ardabil adults. The results indicated that food price is the most critical food choice motivation. Based on this study results, the food policymaker can change people food security and food choices with some programs like as healthy food subsidies and unhealthy food taxes.
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Allan de Guzman, Sean Frances Barredo and Kim Rajah Caillan
Previous studies suggest that the care for elderly prisoners is a growing problem. The emerging phenomenon such as the correctional ageing crisis is an urgent concern that needs…
Abstract
Purpose
Previous studies suggest that the care for elderly prisoners is a growing problem. The emerging phenomenon such as the correctional ageing crisis is an urgent concern that needs to be collectively and holistically addressed from a multi-sectoral perspective. In a developing country, like the Philippines, where prison congestion is alarming, the need for more empirical investigations that probe into the prison life and services is warranted to better inform penal policy and practice that would improve health outcomes among incarcerated individuals. The purpose of this study is to examine the extent to which depression among Filipino elderly prisoners shape their food choices.
Design/methodology/approach
A survey of 160 Filipino elderly prisoners of age 60 and above from October to November 2018 was conducted using a three-part research instrument, which consists of a personal and nutrition-related checklist, 15-point geriatric depression scale and a set of cards that were ranked and sorted through the balanced incomplete block design.
Findings
Results of the survey were subjected to conjoint analysis and structural equation modeling using the Statistical Package for the Social Sciences 24. Interestingly, taste was the most considered attribute (30.765%) while portion size (9.759%) is the least considered by the Filipino elderly prisoners. Notably, depression has a significant positive effect on their food preferences in all attributes except portion size.
Research limitations/implications
This study was limited to two prison settings in the Philippines. Considering the results from the conjoint analysis, strategies can be developed in designing an individualized meal plan suitable for the needs of each elderly prisoner. Also, sizeable government appropriations should be in place to ensure the nutritional quality of food served to aging Filipino prisoners.
Practical implications
Provisions for a pool of nutritionists working hand in hand with other health members would guarantee a prison system that promotes the overall well-being of each prisoner. Further, this study can contribute valuable inputs in the menu cycle practice of prisons in the country. There may be a need to prioritize the nutritional aspect of these vulnerable and deprived groups so as to promote a better quality of life among elderly prisoners. Also, other forms of psychosocial, physical and spiritual health activities extended to elderly prisoners may prevent depressive symptoms.
Originality/value
Conjoint analysis is remarkably gaining prominence in not only the health-care setting (Phillips et al., 2002; Ryan and Farrar, 2000) but also the field of nutrition. It holds a number of unique and practical promises to prison settings.
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Iuri Yudi Furukita Baptista, Fabiana Carvalho, Priscilla Efraim, Paulo Túlio de Souza Silveira and Jorge Behrens
Research on cross-modal sensory interactions has shown that visual aspects of food can influence consumer's expectation and perception of taste, mouthfeel and liking. This paper…
Abstract
Purpose
Research on cross-modal sensory interactions has shown that visual aspects of food can influence consumer's expectation and perception of taste, mouthfeel and liking. This paper aims to investigate the effects of a rounded (“bouba”) and a squared (“kiki”) shape on expected and perceived sweetness, bitterness, creaminess and liking of chocolates.
Design/methodology/approach
Brazilian consumers (N = 230) divided into two groups of 115 individuals each evaluated five chocolates containing 30, 40, 50, 60 and 70% of cocoa. One of the groups evaluated all formulations in the rounded shape and the other in the squared shape. Results were analysed with mixed multivariate analysis of variance (mixed-MANOVA) between shapes, repeated-measures MANOVA between pre- and post-tasting and Pearson's correlation analysis was performed between liking ratings and sweetness, bitterness and creaminess confirmation/disconfirmation.
Findings
The study found significant effects (p < 0.05) of shape on expected and perceived creaminess but not on other attributes; of cocoa percentage (30, 40, 50, 60 and 70%) on all four attributes; and time (pre- and post-tasting) on sweetness, bitterness and liking but not creaminess. Finally, it found significant negative correlations between the creaminess difference indices and the liking ratings for the 30, 50 and 60% chocolates.
Originality/value
This study reports that consumers may expect and perceive chocolates as creamier in a rounded shape than in an angular shape and that if the expectation of creaminess is not confirmed by sensory perception, acceptability may be negatively affected.
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Laurent Sabourin, Kévin Subrin, Richard Cousturier, Grigoré Gogu and Youcef Mezouar
The robot offers interesting capabilities, but suffers from a lack of stiffness. The proposed solution is to introduce redundancies for the overall improvement of different…
Abstract
Purpose
The robot offers interesting capabilities, but suffers from a lack of stiffness. The proposed solution is to introduce redundancies for the overall improvement of different capabilities. The management of redundancy associated with the definition of a set of kinematic, mechanical and stiffness criteria enables path planning to be optimized.
Design/methodology/approach
The resolution method is based on the projection onto the kernel of the Jacobian matrix of the gradient of an objective function constructed by aggregating kinematic, mechanical and stiffness weighted criteria. Optimized redundancy management is applied to the 11-DoF (degrees of freedom) cells to provide an efficient placement of turntable and track. The final part presents the improvement of the various criteria applied to both 9-DoF and 11-DoF robotic cells.
Findings
The first application concerns the optimized placement of a turntable and a linear track using 11-DoF architecture. Improved criteria for two 9-DoF robotic cells, a robot with parallelogram closed loop and a Tricept are also presented. Simulation results present the contributions of redundancies and the leading role of the track.
Research limitations/implications
The redundancy-based optimization presented and the associated simulation approach must be completed by the experimental determination of the optimization criteria to take into account each machining strategy.
Practical implications
This work in robotics machining relates to milling operations for automotive and aerospace equipment. The study is carried out within the framework of the RobotEx Equipment of Excellence programme.
Originality/value
The resolution method to optimized path planning is applied to 9- and 11-DoF robotic cells, including a hybrid robot with a parallelogram closed loop and a Tricept PKM.
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