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Particle velocity is a critical factor that can affect the deposition quality in manufacturing processes involving the use of a laser source and a powder‐particle delivery nozzle. The purpose of this paper is to propose a method to detect the speed and trajectory of particles during a laser deposition process.

A low‐power laser light sheet technique is used to illuminate particles emerging from a custom designed powder delivery nozzle. Light scattered by the particles is detected by a high‐speed camera. Image processing on the acquired images was performed using both edge detection and Hough transform algorithms.

The experimental data were analyzed and used to estimate particle velocity, trajectory and the velocity profile at the nozzle exit. The results have demonstrated that the particle trajectory remains linear between the nozzle exit and the deposition plate and that the particle velocity can be considered a constant.

The use of low‐power laser light sheet illumination facilitates the detection of isolated particle streaks even in high‐powder flow rate condition. Identification of particle streaks in three subsequent images ensures that particle velocity vectors are in the plane of illumination, and also offers the potential to evaluate in a single measurement both velocity and particle size based on the observed scattered characteristics. The method provides a useful simple tool to investigate particle dynamics in a rapid prototyping application as well as other research fields involving the use of powder delivery nozzles.

Understanding social studies programs at science, technology, mathematics and engineering (STEM) schools is becoming increasingly important as the number of STEM schools grows. This study undertook a qualitative investigation into social studies programs at two STEM high schools. Interviews from social studies teachers, principals, and students were transcribed, coded, and analyzed. Additional data was collected through observation and document analysis. Findings highlighted social studies teachers’ perceptions that a strong social studies curriculum is essential to STEM education; the opportunities of interdisciplinary and technology integration afforded to social studies STEM teachers; and some of the challenges of teaching social studies in a STEM school. The researcher discusses the implications of these findings for stakeholders in the social studies to ensure citizens are equipped with the needed skill, knowledge, and dispositions to compete in a global and multicultural age.

The purpose of this paper is to present a first proposal of a healthy dietary diversity index to evaluate meals in self-service restaurants.

This was a cross-sectional, descriptive pilot study in a Brazilian buffet-style restaurant. The study group was selected by systematic sampling and consisted of 678 individuals aged 16-81 years, who were regular diners at a selected restaurant during lunchtime. Photographs were used to assess food choices and a sociodemographic questionnaire was administered to the subjects. A healthy dietary diversity model was created following WHO recommendations and the Brazilian Food Guide. A consensus workshop was conducted with experts to discuss and classify certain dishes as more or less healthy (high/low energy density). The model attributed negative (−3.0-0.0) and positive (0.0-12.0) scores to different food groups. Higher scores meant greater diversity on the plate, and therefore a greater chance of a healthy meal (=9.0), while a lower score reflected a higher variety of energy-dense foods, such as fried dishes (=6.0).

Most diner’s plates (65.3 per cent) obtained low diversity score indexes (=6) and were considered inadequate, represented the dishes where intake should be controlled from a nutritional viewpoint (over caloric meal). There was a significant association between healthy diversity scores (=9.0) and low variety of high energy density dishes on the plates.

This method of assessing the healthy dietary diversity of a main meal could be tested as an innovative model for investigating the food choices of individuals who eat away from home.

This paper aims to investigate the effect of four important process parameters (i.e. laser focal distance, travel speed, feeding gas flow rate and standoff distance) on the size of single clad geometry created by coaxial nozzle-based powder deposition by high power laser.

Design of experiments (DOE) and statistical analysis methods were both used to find optimum parameter combinations to get minimum sized clad, i.e. clad width and clad height. Factorial experiment arrays were used to design parameter combinations for creating experimental runs. Taguchi optimization methodology was used to find out optimum parameter levels to get minimum sized clad geometry. Response surface method was used to investigate the nonlinearity among parameters and variance analysis was used to assess the effectiveness level of each problem parameters.

The overall results show that wisely selected four problem parameters have the most prominent effects on the final clad geometry. Generally, minimum clad size was achieved at higher levels of gas flow rate, travel speed and standoff distance and at minimum spot size level of the laser focal distance.

This study presents considerable contributions in assessing the importance level of problems parameters on the optimum single clad geometry created laser-assisted direct metal part fabrication method. This procedure is somewhat complicated in understanding the effects of the selected problem parameters on the outcome. Therefore, DOE methodologies are utilized so that this operation can be better modeled/understood and automated for real life applications. The study also gives future direction for research based on the presented results.

In order to connect a fiberglass composite structure to a steel structure, a hybrid composite made of glass and steel fibers has been studied. The hybrid composite has one end section with all glass fibers and the opposite end section with all steel fibers. As a result, it contains a transition section in the middle of the hybrid composite changing from glass fibers to steel fibers. The purpose of this paper is to examine interface strength at the glass to steel fiber transition section, in order to evaluate the effectiveness of the hybrid composite as a joining technique between a polymer composite structure and a metallic structure.

The present micromechanical study considers two types of glass to steel fiber joints: butt and overlap joints. For the butt joint, the end shape of the steel fiber is also modified to determine its effect on interface strength. The interface strength is predicted numerically based on the virtual crack closure technique to determine which joint is the strongest under various loading conditions such as tension, shear and bending. Numerical models include resin layers discretely. A virtual crack is considered inside the resin, at the resin/glass‐layer interface, and at the resin/steel‐layer interface. The crack is located at the critical regions of the joints.

Overall, the butt joint is stronger than the overlap joint regardless of loading types and directions. Furthermore, modification of an end shape of the middle fiber layers in the butt joint shifts the critical failure location.

The paper describes one of a few studies which investigated the interface strength of the hybrid joint made of fiberglass and steel‐fiber composites. This joint is important to connect a polymeric composite structure to a metallic structure without using conventional mechanical joints.

Nobody concerned with political economy can neglect the history of economic doctrines. Structural changes in the economy and society influence economic thinking and, conversely, innovative thought structures and attitudes have almost always forced economic institutions and modes of behaviour to adjust. We learn from the history of economic doctrines how a particular theory emerged and whether, and in which environment, it could take root. We can see how a school evolves out of a common methodological perception and similar techniques of analysis, and how it has to establish itself. The interaction between unresolved problems on the one hand, and the search for better solutions or explanations on the other, leads to a change in paradigma and to the formation of new lines of reasoning. As long as the real world is subject to progress and change scientific search for explanation must out of necessity continue.

The purpose of this study is to explore the relationship between nutritional status and associated risk factors such as:, socio-economic, physical, pathological and psychological factors, among elderly residing in Lebanese nursing homes.

This cross-sectional study was carried out in 36 elderly care nursing homes with 2,094 residents. Of these, only 221 (11 per cent) elderly met the inclusion criteria and successfully completed the interview question. Data on socio-demographic characteristics and health conditions: oral, nutritional, depression, chronic diseases and activities of daily living, were collected. The analysis used a chi-square test and a binary logistic regression.

High levels of malnourishment were found among elderly who had no jobs (p = 0.012) and had oral health problems (p = 0.038), functional impairment (p < 0.001) and depression (p = 0.021). Comorbid illnesses, however, had no significant association with nutritional status. In addition, the first and strongest predictor entered in the regression on malnutrition was functional impairment (p = 0.002) followed by oral health problems (p = 0.030) and depression (p = 0.036).

The study is original in the sense that it emphasized the importance of three factors, autonomy, better oral and psychological health, in mediating nutritional outcomes for elderly residing in nursing homes.

The purpose of this study is to examine whether brand perceptions differ across channel members of luxury brands using the buyer‐seller exchange situation model.

A triangulation approach was used to compare perceptions of different channel members. The data collection was completed in two stages. First, a self‐administered mail survey was sent out to 3,592 individuals from a publicly available mailing list. In‐depth interviews were conducted with 22 retailer buyers.

The findings reveal that brand perceptions differ across channel members. There appears to be a mismatch in the perceptions of wholesalers and retailers that might constitute a source of brand image inconsistencies. Although the final consumers' overall attitude toward the Hugo Boss brand is positive, consumers appear to be in favour of other brands and their inclination to purchase the Hugo Boss brand seems to be relatively low.

The study only examined one brand and is limited to the Australian context. Future research could examine other luxury brands in different countries. The study utilised judgement sampling, which could result in selection bias.

Brand knowledge is crucial to achieving brand image consistency between seller and buyer. Internal marketing techniques could be employed to assess the efficiency and development of brand knowledge among employees, retailers and other channel members.

This is one of the pioneering studies that applies a marketing channel approach to investigate brand image inconsistencies in a concrete working example. It contributes to luxury brand management across borders, opening the way for further research. The study provides ecological validity and reliability by working on a triangulation approach, using qualitative and quantitative research methods.

Discusses principles of equality and justice in order to justify affirmative action and clarify its need. Posits that in both the USA and South Africa, issues of segregation and discrimination are not new and both countries have had the opportunity to address their past policies by way of affirmative action programmes. Looks at what determined the denouncement of the affirmative action in the USA and why the answer to this question may have a great impact on South Africa’s attempt to improve its own affirmative action programmes. Concludes that, although 30 years of affirmative action was deemed unconstitutional, how can South Africa derive and make use of the knowledge gained to help in stopping reverse discrimination.

The steadily growing popularity of additive manufacturing (AM) increases the demand for understanding fundamental behaviors of these processes. High-speed imaging (HSI) can be a useful tool to observe these behaviors, but many studies only present qualitative analysis. The purpose of this paper is to propose an algorithm-assisted method as an intermediate to rapidly quantify data from HSI. Here, the method is used to study melt pool surface profile movement in a cold metal transfer-based (CMT-based) AM process, and how it changes when the process is augmented with a laser beam.

Single-track wide walls are generated in multiple layers using only CMT, CMT with leading and with trailing laser beam while observing the processes using HSI. The studied features are manually traced in multiple HSI frames. Algorithms are then used for sorting measurement points and generating feature curves for easier comparison.

Using this method, it is found that the fluctuation of the melt surface in the chosen CMT AM process can be reduced by more than 35 per cent with the addition of a laser beam trailing behind the arc. This indicates that arc and laser can be a viable combination for AM.

The suggested quantification method was used successfully for the laser-arc hybrid process and can also be applied for studies of many other AM processes where HSI is implemented. This can help fortify and expand the understanding of many phenomena in AM that were previously too difficult to measure.