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1 – 10 of over 46000Hannah Weiss, Yaritza Hernandez, K. Han Kim and Sudhakar L. Rajulu
The suboptimal fit of a spacesuit can interfere with a crewmember's performance and is regarded as a potential risk factor for injury. To quantify suit fit, a virtual fit…
Abstract
Purpose
The suboptimal fit of a spacesuit can interfere with a crewmember's performance and is regarded as a potential risk factor for injury. To quantify suit fit, a virtual fit assessment model was previously developed to identify suit-to-body contact and interference using 3D human body scans and suit CAD models. However, ancillary suit components and garments worn inside of the suit have not been incorporated.
Design/methodology/approach
This study was conducted to predict a 3D model of the liquid cooling and ventilation garment (LCVG) from an arbitrary person's body scan. A total of 14 subjects were scanned in a scan wear and LCVG condition. A statistical model was generated using principal component analysis and random forest regression technique.
Findings
The model was able to predict the geometry of the LCVG layer at the accuracy of 5.3 cm maximum error and 1.7 cm root mean square error. The errors were more pronounced for the arms and lower torso, while the thighs and upper torso regions, which are critical for suit fit assessments, show more accurate predictions. A case study of suit fit with and without the LCVG model demonstrated that the new model can enhance the scope and accuracy of future spacesuit assessments.
Originality/value
The capabilities resulting from these modeling techniques would greatly expand the assessments of fit of the garment on various anthropometries. The results from this study can significantly improve the design process modeling and initial suit sizing efforts to optimize crew performance during extravehicular activity training and missions.
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Erina Baynojir Joyee, Jida Huang, Ketki Mahadeo Lichade and Yayue Pan
The purpose of this study is to develop a novel approach to designing locally programmed multi-material distribution in a three-dimensional (3D) model, with the goal of…
Abstract
Purpose
The purpose of this study is to develop a novel approach to designing locally programmed multi-material distribution in a three-dimensional (3D) model, with the goal of producing a biomimetic robot that could mimic the locomotion of living organisms.
Design/methodology/approach
A voxelized representation is used to design the multi-material digital model and the material distribution in the model is optimized with the aims of mimicking the deflection dynamics of a real-life biological structure (i.e. inchworms) during its locomotion and achieving smooth deflection between adjacent regions. The design is validated post-fabrication by comparing the bending profiles of the printed robot with the deflection reference images of the real-life organism.
Findings
The proposed design framework in this study provides a foundation for multi-material multi-functional design for biomimicry and a wide range of applications in the manufacturing field and many other fields such as robotics and biomedical fields. The final optimized material design was 3D printed using a novel multi-material additive manufacturing method, magnetic field-assisted projection stereolithography. From the experimental tests, it was observed that the deflection curve and the deflection gradient of the printed robot within the adjacent regions of the body agreed well with the profiles taken from the real-life inchworm.
Originality/value
This paper presents a voxelized digital representation of the material distribution in printed parts, allowing spatially varied programming of material properties. The incorporation of reference images from living organisms into the design approach is a novel approach to transform image domain knowledge into the domain of engineering mechanical and material properties. Furthermore, the novel multi-material distribution design approach was validated through designing, 3D printing and prototyping an inchworm-inspired soft robot, which showed superior locomotion capability by mimicking the observed locomotion of the real inchworm.
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Iat‐Fai Leong, Jing‐Jing Fang and Ming‐June Tsai
The purpose of this paper is to propose a method to automatically generate individualized body size measurements from cloud point of a body scanner. It aims to propose a…
Abstract
Purpose
The purpose of this paper is to propose a method to automatically generate individualized body size measurements from cloud point of a body scanner. It aims to propose a fast, reliable, and unambiguous method to obtain human body measurements for use in the garment industry.
Design/methodology/approach
Based on a previous study by the authors, geometric features on the scanned body are identified by computerized algorithms through mathematical definitions. Feature lines situated on the human body surface are created as polylines that pass through the body's features and three types of computer measurements (tape‐measurement, contour‐measurement, and linear‐measurement) are provided.
Findings
By dividing the body surface into rectangular patches using the feature lines as boundaries, the body can be reconstructed easily with a minimal amount of triangles while retaining the essential shape. The proposed measuring method applies to most manual measurements used in the garment industry. The authors evaluated the anthropometry variations of the same subject to explore the reliability of the proposed method. It was found that the precision of the method is well below the standard requirement of the traditional manual method.
Research limitations/implications
In this research, subjects were scanned in standing pose; this pose minimizes regions obstructed by body parts and permits maximal acquisition of as many key landmarks. Since the features are identified by geometric analysis without the need for marker attachment, measurements of the required sitting position are impossible to obtain in the current study.
Originality/value
Resolution of meshing can be changed according to application requirements. Contrary to the traditional manual method, efficiency and precision are the advantages of the present method.
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Felipe Sant'Anna Nunes, Helcio R.B. Orlande and Andrzej J. Nowak
This study deals with the computational simulation and inverse analysis of the cooling treatment of the hypoxic-ischemic encephalopathy in neonates. A reduced-order model…
Abstract
Purpose
This study deals with the computational simulation and inverse analysis of the cooling treatment of the hypoxic-ischemic encephalopathy in neonates. A reduced-order model is implemented for real-time monitoring of the internal body temperatures. The purpose of this study is to sequentially estimate the transient temperatures of the brain and other body regions with reduced uncertainties.
Design/methodology/approach
Pennes’ model was applied in each body element, and Fiala’s blood pool concept was used for the solution of the forward bioheat transfer problem. A state estimation problem was solved with the Sampling Importance Resampling (SIR) algorithm of the particle filter method.
Findings
The particle filter method was stable and accurate for the estimation of the internal body temperatures, even in situations involving large modeling and measurement uncertainties.
Research limitations/implications
The proposed reduced-order model was verified with the results of a high-fidelity model available in the literature. Validation of the proposed model and of the solution of the state estimation problem shall be pursued in the future.
Practical implications
The solution of the state estimation problem with the reduced-order model presented in this paper has great potential to perform as an observer of the brain temperature of neonates, for the analysis and control of the systemic cooling treatment of neonatal hypoxic-ischemic encephalopathy.
Social implications
The main treatment for hypoxic-ischemic encephalopathy in neonates is the cooling of affected regions. Accurate and fast models might allow the development of individualized protocols, as well as control strategies for the cooling treatment.
Originality/value
This paper presents the application of the SIR algorithm for the solution of a state problem during the systemic cooling of a neonate for the treatment of the hypoxic-ischemic encephalopathy.
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Hiroyuki Ueda, Yoshimitsu Inoue, Mitsuo Matsudaira, Tsutomu Araki and George Havenith
The aim of this study is to explore the influence of the clothing ventilation in three body regions on the humidity of the local clothing microclimates under five…
Abstract
Purpose
The aim of this study is to explore the influence of the clothing ventilation in three body regions on the humidity of the local clothing microclimates under five work‐shirts immediately after the onset of sweating in light exercise.
Design/methodology/approach
The clothing microclimate ventilations were measured at chest, back and upper arm using a manikin. Separate wear trials were performed to determine the sweat production and the humidity of the clothing microclimate at the same locations as where the ventilation was measured during light exercise.
Findings
Every shirt shows the greatest value of ventilation index (VI) for the chest and the smallest one for the upper arm. The values of VI differ remarkably at the chest among the five shirts. Comfort sensation became gradually worse as the time passed after starting exercise. There was no significant difference among the clothing conditions in mean values of rectal temperature, local skin temperatures, microclimate temperatures, microclimate relative humidities and local sweat rates at three regions over 10 min after the onset of sweating. A relationship was observed between the ratio of the mean moisture concentration in the clothing microclimate to the mean sweat rate at the chest and the back and the VI.
Originality/value
The results suggest that clothing ventilation should be measured in different body regions in response to sweat rates in corresponding regions.
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Abstract
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Manoj Kumar Sain and M.L. Meena
Prolonged working in repetitive and awkward postures can result in musculoskeletal disorders among workers involved in labour-intensive jobs like those of brick kiln…
Abstract
Purpose
Prolonged working in repetitive and awkward postures can result in musculoskeletal disorders among workers involved in labour-intensive jobs like those of brick kiln workers. Unlike other labour-intensive sectors, workers in this particular sector have a lack of awareness about musculoskeletal problems. Therefore, the purpose of this paper is to explore musculoskeletal issues and associated risk-factors among brick kiln workers.
Design/methodology/approach
A questionnaire survey was conducted among 217 male and 111 female workers aged between 17 and 53 years. They were employed in traditional brick kiln units situated in Rajasthan, India. Postures were analysed by Rapid Upper Limb Assessment and Rapid Entire Body Assessment methods. Binary logistic regression was used to find the association between musculoskeletal problems and risk-factors.
Findings
For the mould evacuating task, wrist (76.2 per cent) and lower back (56 per cent) issues were the most frequently reported musculoskeletal problems, while in spading task, lower back (62.4 per cent) and shoulder (57.7 per cent) problems were prominent. Musculoskeletal symptoms in one or more body regions were associated with personal and work-related factors including the type of task and experience.
Research limitations/implications
Kiln workers are exposed to high musculoskeletal and postural risks, particularly in spading and mould filling tasks. To reduce these risks, ergonomic interventions are needed.
Originality/value
It is recognised that the musculoskeletal health of brick kiln workers is a cause for concern. The present study provides the evidence of the prevalence of musculoskeletal symptoms experienced by brick kiln workers and the association of symptoms with various risk-factors, which has not been addressed in previous studies.
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H. Parhizkar and S.M.H. Karimian
The purpose of this paper is to present an engineering inviscid‐boundary layer method for the calculation of convective heating rates on three‐dimensional non‐axisymmetric…
Abstract
Purpose
The purpose of this paper is to present an engineering inviscid‐boundary layer method for the calculation of convective heating rates on three‐dimensional non‐axisymmetric geometries at angle of attack.
Design/methodology/approach
Based on the axisymmetric analog, convective heating rates are calculated along the surface streamlines which are determined using the inviscid properties calculated on an unstructured grid.
Findings
Since the method is capable of using inviscid properties calculated on an unstructured grid, it is applicable to a variety of configurations and it requires much less computational effort than a Navier‐Stokes code. The results of the present method are evaluated on different wing body configurations in laminar and turbulent hypersonic equilibrium flows. In comparison to experimental data, the present results are found to be fairly accurate in the windward and leeward regions.
Practical implications
With this approach, heating rates can be predicted on general three‐dimensional configurations at hypersonic speeds in an accurate and fast scheme.
Originality/value
In order to calculate the heating rates at any specific point on the surface, a technique is developed to calculate the inviscid surface streamlines in a backward manner using the inviscid velocity components. The metric coefficients are also calculated using a new simple technique.
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Audrey Gilmore, Aodheen O'Donnell, David Carson and Darryl Cummins
Inward foreign direct investment (FDI) is regarded as an important means of employment and knowledge creation in many economies. This study investigates the motivations…
Abstract
Inward foreign direct investment (FDI) is regarded as an important means of employment and knowledge creation in many economies. This study investigates the motivations and satisfaction levels associated with FDI in two economies that are increasingly recognising the benefits of inward investment: Northern Ireland and Bahrain. Although different in may respects, these two regions share similar economic and political characteristics and this study compares the perceptions of the managing directors of foreign companies who have chosen to invest in either of the two regions. It reports that many expected findings were borne out by the study but also highlights pertinent findings that were not anticipated and accordingly that may be of interest to government bodies charged with the responsibility of attracting inward investment.
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Kathryn Brownbridge, Simeon Gill, Sarah Grogan, Sarah Kilgariff and Amanda Whalley
The purpose of this paper is to draw attention to the link between underdeveloped and ill-informed sizing practices, fit dissatisfaction and the creation of textiles…
Abstract
Purpose
The purpose of this paper is to draw attention to the link between underdeveloped and ill-informed sizing practices, fit dissatisfaction and the creation of textiles waste. The literature review identifies: issues that limit the effective development and application of sizing systems, the link between the complexities of consumer fit expectations, body image and self-esteem and maps the link between fit dissatisfaction and the creation of textiles waste.
Design/methodology/approach
Data analysis draws from a wider study designed to investigate women’s experiences of dress fit and body image. In total, 20 women aged 18-45 years were audio recorded while they tried on a number of mass-produced dresses, and were asked to select one dress, which they could keep.
Findings
All the dresses were selected except one style, which failed to satisfy any of the women’s fit requirements. The findings clearly demonstrate why this dress was considered to be unsatisfactory as well as the subsequent link between poor fit and body dissatisfaction.
Social implications
Findings support the theory that women identify with their clothes’ size and when this link is disrupted it causes discomfort and body dissatisfaction, which, in turn, contributed to rejection of the garment increasing the potential for the creation of waste.
Originality/value
This study is the first to link unsatisfactory fashion sizing practice with the production of textiles waste. The process of capturing women’s interactions with high street fashion dresses whilst trying them on enabled a detailed analysis that contributes new evidence to the debate around sizing practice, poor fit and its impact on body image and self-esteem.
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