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The purpose of this study is to offer a better and more effective hexacopter design for a 3 kg payload using finite element analysis (FEA), facilitating the use of different materials for different components that too without compromising strength.

A 3D computer-aided design (CAD) model of a hexacopter with a regular hexagonal frame is presented. Furthermore, a finite element model is developed to perform a structural analysis and determine Von Mises stress and strain values along with deformations of different components of the proposed hexacopter design.

The results establish that carbon fibre outperforms acrylonitrile butadiene (ABS) with respect to deformations. Within the permissible limits of the stress and strain values, both carbon fiber and ABS are suggested for different components. Thus, a proposed hexacopter offers lighter weight, high strength and low cost.

The use of different materials for different components is suggested by making use of static structural analysis. This encourages new research work and helps in developing new applications of hexacopter, and it has never been reported in literature. The suggested materials for the components of the hexacopter will prove to be suitable considering weight, strength and cost.

This paper aims to derive a reduced-order model for the heat transfer across the interface between a millimetric thermocapillary liquid bridge from silicone oil and the surrounding ambient gas.

Numerical solutions for the two-fluid model are computed covering a wide parametric space, making a total of 2,800 numerical flow simulations. Based on the computed data, a reduced single-fluid model for the liquid phase is devised, in which the heat transfer between the liquid and the gas is modeled by Newton’s heat transfer law, albeit with a space-dependent Biot function Bi(z), instead of a constant Biot number Bi.

An explicit robust fit of Bi(z) is obtained covering the whole range of parameters considered. The single-fluid model together with the Biot function derived yields very accurate results at much lesser computational cost than the corresponding two-phase fully-coupled simulation required for the two-fluid model.

Using this novel Biot function approach instead of a constant Biot number, the critical Reynolds number can be predicted much more accurately within single-phase linear stability solvers.

The Biot function for thermocapillary liquid bridges is derived from the full multiphase problem by a robust multi-stage fit procedure. The derived Biot function reproduces very well the theoretical boundary layer scalings.

The main purpose of the study was to synthesise the role of COVID-19 social media messages and indigenous religious beliefs on public health promotion initiatives among rural consumers in Zimbabwe.

A qualitative approach was adopted. Population consisting of 15 interviews and six focus groups was purposively sampled from Manicaland, Mashonaland Central and Masvingo provinces in Zimbabwe. A thematic approach was used to present and analyse the data.

Rural consumers believed WhatsApp messages posted by people whom they know or influential personnel like health workers. Credibility of WhatsApp messages was enhanced through its ability to send videos and audios. Teachings and indoctrination by indigenous churches and misinformation were found to be an impediment in believing COVID-19 WhatsApp messages and vaccination by rural consumers. Faith healers in indigenous churches used various practices and artefacts like holy water, stone pebbles, clay pots, flags and wooden rods to pray and treat patients suffering from COVID-19 and other ailments.

Social media messages, religious teachings and indoctrination may be a hindrance to rural consumers in adopting government public health promotion initiatives; hence, public health professionals need prior emic understanding and co-option of local leadership in vaccination campaigns.

This study outstretches the theoretical landscape in consumer behaviour and also practical contribution to health practitioners and marketers on breaking indigenous religious barriers and social media misconceptions on vaccination uptake through promotional strategies earmarked for rural consumers.

This study aims to design and validate a theoretical model for capacitive imaging (CI) sensors that incorporates the interelectrode shielding and surrounding shielding electrodes. Through experimental verification, the effectiveness of the theoretical model in evaluating CI sensors equipped with shielding electrodes has been demonstrated.

The study begins by incorporating the interelectrode shielding and surrounding shielding electrodes of CI sensors into the theoretical model. A method for deriving the semianalytical model is proposed, using the renormalization group method and physical model. Based on random geometric parameters of CI sensors, capacitance values are calculated using both simulation models and theoretical models. Three different types of CI sensors with varying geometric parameters are designed and manufactured for experimental testing.

The study’s results indicate that the errors of the semianalytical model for the CI sensor are predominantly below 5%, with all errors falling below 10%. This suggests that the semianalytical model, derived using the renormalization group method, effectively evaluates CI sensors equipped with shielding electrodes. The experimental results demonstrate the efficacy of the theoretical model in accurately predicting the capacitance values of the CI sensors.

The theoretical model of CI sensors is described by incorporating the interelectrode shielding and surrounding shielding electrodes into the model. This comprehensive approach allows for a more accurate evaluation of the detecting capability of CI sensors, as well as optimization of their performance.

The purpose of this paper is to investigate the distribution characteristics of airflow in mine ventilation suits with different pipeline structures when the human body is bent at various angles. On this basis, the stress points are extracted to investigate the pressure variation of a ventilation suit under different ventilation rates and pipeline structures.

Based on the three-dimensional human body scanner, portable pressure test and other instruments, a human experiment was conducted in an artificial cabin. The study analyzed and compared the distribution characteristics of clearance under three different pipeline structures, as well as the pressure variation of the ventilation suit.

The study found that the clearance in front of two pipeline structures gradually increased in size as the degree of bending increased, and there was minimal clearance in the chest and back. The longitudinal structure exhibits a significant decrease in clearance compared to the spiral structure. The pressure value of the spiral pipeline structure with the same ventilation volume is low, followed by the transverse structure, while the longitudinal structure has the highest pressure value. The increase in clothing pressure value of a spiral pipeline structured ventilation suit with varying ventilation volumes is minimal.

The ventilation suit has a promising future as a type of personal protective equipment for mitigating heat damage in mines. It is of great value to study the pipeline structure of the ventilation suit for human comfort.

The purpose of this study is to extract and characterize a novel natural dye from the leaves of Lannea coromandelica and the extraction with finding ways of dyeing cotton fabric using three mordants.

The colouring agents were extracted from the leaves of Lannea coromandelica using an aqueous extraction method. The extract was characterized using analysis methods of pH, gas chromatography-mass spectrometry (GC-MS), Fourier transform infrared (FTIR), ultraviolet-visible (UV-vis) and cyclic voltammetry measurement. The extract was applied to cotton fabric samples using a non-mordant and three mordants under the two mordanting methods. The dyeing performance of the extracted colouring agent was evaluated using colour fastness properties, colour strength (K/S) and colour space (CIE Lab).

The aqueous dye extract showed reddish-brown colour, and its pH was 5.94. The GC-MS analysis revealed that the dye extract from the leaves of Lannea coromandelica contained active chemical compounds. The UV-vis and FTIR analyses found that groups influenced the reddish-brown colour of the dye extraction. The cyclic voltammetry measurements discovered the electrochemical properties of the dye extraction. The mordanted fabric samples showed better colour fastness properties than the non-mordanted fabric sample. The K/S and CIE Lab results indicate that the cotton fabric samples dyed with mordants showed more significant dye affinities than non-mordanted fabric samples.

Researchers have never discovered that the Lannea coromandelica leaf extract is a natural dye for cotton fabric dyeing. The findings of this study showed that natural dyes extracted from Lannea coromandelica leaf could be an efficient colouring agent for use in cotton fabric.

This case is used in Darden's required first-year course, “Strategic Thinking and Action.”

In 2015, Steve and Heidi Crandall, the founders of Devils Backbone Brewing, LLC (DBB), were looking back on eight years of unanticipated success and significant growth. DBB had created a destination, a brand, and beer that drew people from all over, and it was the largest craft brewery in its region. The entire community, not just loyal beer drinkers, had supported DBB. In addition to funding and zoning accommodations, so many local residents had built their own economic lives around what had been their “little brewery that could.”

But the success had brought challenges, specifically in terms of growth. DBB was consistently not meeting demand in its existing markets and was receiving complaints about out-of-stocks. The Crandalls and their team had to figure out how to grow with, or preferably ahead of, demand for DBB's product. Should DBB build further capacity despite an already exhausted line of credit? Should it employ a contract brewer despite the local authenticity concerns such a move might stir up? Or should it just keep trying to manage business within its existing footprint, comfortably serving its loyal customer base?

This study aims to explore and understand the challenges and opportunities presented by the rising demand for organic products in the context of toddy consumption and marketing.

This research examines consumer behaviour and decision-making patterns using decision tree analysis. A survey questionnaire based on established theories was distributed to individuals above the legal drinking age of 23 in Kerala, India, using purposive and random sampling.

The study found that people's fondness for toddy shop food plays a crucial role in their food choices. When the fondness is low, subjective norms can override personal preferences. But when the fondness is high, individual perceptions take precedence.

Using machine learning techniques, we created a compass to guide marketing strategies and cultural preservation efforts in toddy shops by considering the complex factors that influence consumer decisions.