Grading zero waste design using digital and virtual methods

Doctor of PhilosophyDepartment of Apparel, Textiles, and Interior DesignSherry J. HaarTraditional practices of pattern cutting within the apparel industry result in a considerable portion of fabric waste that negatively impacts the environment. Currently, garment manufacturers make responding to fashion trends, at the lowest possible cost, the main priority, regardless of fabric waste, to ensure economic profit. Besides, one of the sustainable challenges when working with zero waste design (ZWD) is the feasibility of pattern grading under the current apparel production system. Thus, the purpose of this experimental study was to explore the feasibility of grading zero waste garments for industry production using digital and virtual methods. The main research questions in this study were: What pattern piece adjustments and marker layouts achieve both 100% marker efficiency and accurate virtual visual appearance? Can digital 3D simulation be used as an effective and sustainable sizing and fit assessment tool? Does attachment and appreciation of ZWD influence expert judges’ evaluation of visual accuracy? The first research question was answered through a functional design process that included three phases: sample development, grading and marker making, digital and virtual testing of marker adjustments, and marker refinement. The application of typical and novel marker making and design tactics for functional utilization of the cuts offs resulting in no fabric waste of the mixed marker of the graded sizes was explored. As a result, a system of four different adjustment methods were applied to reach 100% marker efficiency while maintaining visual accuracy. Multiple challenges regarding the use of 3D simulation to create virtual samples were encountered. To answer the second and third research questions, an online questionnaire was utilized to collect assessment related to the efficiency of the graded virtual samples compared to the physical based on particular design criteria. Two judge groups participated in this study, zero waste design academic researchers and industry technical designers. The judges compared the samples via video, between and across groups. The findings indicated that the use of 3D simulation was mostly challenging for grading ZWD while maintaining 100% marker efficiency and visual accuracy. Judges suggested that the 3D simulation would be a useful, sustainable tool for fit and appearance assessment to decrease the number of physical samples; however, major improvements for the software were recommended before the physical sample could be eliminated. These findings contribute to understanding the effectiveness of sizing zero waste design and use of 3D virtual simulation as an assessment method, which promotes sustainable development through pattern making within the production methods in the apparel industry. Technical judges had more agreement than ZWD judges regarding the similarity between virtual and physical samples, and the sufficiency of information provision by virtual samples that would replace physical samples. Thus, ZWD judges had higher expectations for virtual technology. This finding indicated a relationship between attachment and appreciation of sustainability in fashion with the adoption of advanced practices to develop sustainable fashion design through the functional design process

Patient-specific image-based computer simulation for theprediction of valve morphology and calcium displacement after TAVI with the Medtronic CoreValve and the Edwards SAPIEN valve

AIMS: Our aim was to validate patient-specific software integrating baseline anatomy and biomechanical properties of both the aortic root and valve for the prediction of valve morphology and aortic leaflet calcium displacement after TAVI. METHODS AND RESULTS: Finite element computer modelling was performed in 39 patients treated with a Medtronic CoreValve System (MCS; n=33) or an Edwards SAPIEN XT (ESV; n=6). Quantitative axial frame morphology at inflow (MCS, ESV) and nadir, coaptation and commissures (MCS) was compared between multislice computed tomography (MSCT) post TAVI and a computer model as well as displacement of the aortic leaflet calcifications, quantified by the distance between the coronary ostium and the closest calcium nodule. Bland-Altman analysis revealed a strong correlation between the observed (MSCT) and predicted frame dimensions, although small differences were detected for, e.g., Dmin at the inflow (mean±SD MSCT vs. MODEL: 21.6±2.4 mm vs. 22.0±2.4 mm; difference±SD: -0.4±1.3 mm, p<0.05) and Dmax (25.6±2.7 mm vs. 26.2±2.7 mm; difference±SD: -0.6±1.0 mm, p<0.01). The observed and predicted calcium displacements were highly correlated for the left and right coronary ostia (R2=0.67 and R2=0.71, respectively p<0.001). CONCLUSIONS: Dedicated software allows accurate prediction of frame morphology and calcium displacement after valve implantation, which may help to improve outcome

A method for three-dimensional particle sizing in two-phase flows

A method is devised for true three-dimensional (3D) particle sizing in two-phase systems. Based on a ray-optics approximation of the Mie scattering theory for spherical particles, and under given assumptions, the principle is applicable to intensity data from scatterers within arbitrary interrogation volumes. It requires knowledge of the particle 3D location and intensity, and of the spatial distribution of the incident light intensity throughout the measurement volume. The new methodology is particularly suited for Lagrangian measurements: we demonstrate its use with the defocusing digital particle image velocimetry technique, a 3D measurement technique that provides the location, intensity and velocity of particles in large volume domains. We provide a method to characterize the volumetric distribution of the incident illumination and we assess experimentally the size measurement uncertainty

A review of contemporary techniques for measuring ergonomic wear comfort of protective and sport clothing

Protective and sport clothing is governed by protection requirements, performance, and comfort of the user. The comfort and impact performance of protective and sport clothing are typically subjectively measured, and this is a multifactorial and dynamic process. The aim of this review paper is to review the contemporary methodologies and approaches for measuring ergonomic wear comfort, including objective and subjective techniques. Special emphasis is given to the discussion of different methods, such as objective techniques, subjective techniques, and a combination of techniques, as well as a new biomechanical approach called modeling of skin. Literature indicates that there are four main techniques to measure wear comfort: subjective evaluation, objective measurements, a combination of subjective and objective techniques, and computer modeling of human–textile interaction. In objective measurement methods, the repeatability of results is excellent, and quantified results are obtained, but in some cases, such quantified results are quite different from the real perception of human comfort. Studies indicate that subjective analysis of comfort is less reliable than objective analysis because human subjects vary among themselves. Therefore, it can be concluded that a combination of objective and subjective measuring techniques could be the valid approach to model the comfort of textile materials

Computing an Optimal Control Policy for an Energy Storage

We introduce StoDynProg, a small library created to solve Optimal Control problems arising in the management of Renewable Power Sources, in particular when coupled with an Energy Storage System. The library implements generic Stochastic Dynamic Programming (SDP) numerical methods which can solve a large class of Dynamic Optimization problems. We demonstrate the library capabilities with a prototype problem: smoothing the power of an Ocean Wave Energy Converter. First we use time series analysis to derive a stochastic Markovian model of this system since it is required by Dynamic Programming. Then, we briefly describe the "policy iteration" algorithm we have implemented and the numerical tools being used. We show how the API design of the library is generic enough to address Dynamic Optimization problems outside the field of Energy Management. Finally, we solve the power smoothing problem and compare the optimal control with a simpler heuristic control.Comment: Part of the Proceedings of the 6th European Conference on Python in Science (EuroSciPy 2013), Pierre de Buyl and Nelle Varoquaux editors, (2014

Service Knowledge Capture and Reuse

The keynote will start with the need for service knowledge capture and reuse for industrial product-service systems. A novel approach to capture the service damage knowledge about individual component will be presented with experimental results. The technique uses active thermography and image processing approaches for the assessment. The paper will also give an overview of other non-destructive inspection techniques for service damage assessment. A robotic system will be described to automate the damage image capture. The keynote will then propose ways to reuse the knowledge to predict remaining life of the component and feedback to design and manufacturing

Computed Tomography-Derived 3D Modeling to Guide Sizing and Planning of Transcatheter Mitral Valve Interventions

A plethora of catheter-based strategies have been developed to treat mitral valve disease. Evolving 3-dimensional (3D) multidetector computed tomography (MDCT) technology can accurately reconstruct the mitral valve by means of 3-dimensional computational modeling (3DCM) to allow virtual implantation of catheter-based devices. 3D printing complements computational modeling and offers implanting physician teams the opportunity to evaluate devices in life-size replicas of patient-specific cardiac anatomy. MDCT-derived 3D computational and 3D-printed modeling provides unprecedented insights to facilitate hands-on procedural planning, device training, and retrospective procedural evaluation. This overview summarizes current concepts and provides insight into the application of MDCT-derived 3DCM and 3D printing for the planning of transcatheter mitral valve replacement and closure of paravalvular leaks. Additionally, future directions in the development of 3DCM will be discussed

Men’s Jeans Fit Based on Body Shape Categorization

The purpose of this study was to categorize lower body shape in men and to investigate the interplay between body shape and fitting issues appearing in men’s jeans. More specifically, the goal of the study was to improve apparel fit based on body shape. The detailed objectives of the study were to: (1) Categorize male body shapes using statistical analysis; (2) use 3D virtual fitting technology to assess fit and develop a shape-driven pants block pattern for each body shape. This quantitative study was conducted in three stages: (1) categorizing the body shape of 1420 male scans, aged 18-35, from the SizeUSA dataset, (2) develop a shape-driven pants block pattern for each identified body shape, and (3) validate the developed blocks by virtually trying the shape-driven block pattern on fit testers from different body shape groups. Exploratory Factor Analysis (EFA) and cluster analysis were used for body shape categorization, which resulted in three different body shapes: (1) Flat-Straight, (2) Moderate Curvy-Straight, and (3) Curvy. Three fit models were selected from each identified body shape group and then patterns were developed using Armstrong’s (2005) jeans foundation method. Patterns were modified and fitted to the selected representative fit models of each body shape group. The developed shape-driven block patterns were simulated on the fit testers to further explore the relationship between body shape and fit issues. This study suggests that two individuals with identical body measurements may experience very different fit problems tailored to their different body shapes. It was found that each body shape would exclusively experience unique fit issues. Furthermore, the shape driven block patterns were found to be highly correlated with their host body shape category. This research implies that if the mass customization process starts with block patterns that are engineered for specific body shape categories significantly less fit issues would appear and the desired fit would be achieved in fewer fitting sessions

Application of laminar flow control to supersonic transport configurations

The feasibility and impact of implementing a laminar flow control system on a supersonic transport configuration were investigated. A hybrid laminar flow control scheme consisting of suction controlled and natural laminar flow was developed for a double-delta type wing planform. The required suction flow rates were determined from boundary layer stability analyses using representative wing pressure distributions. A preliminary design of structural modifications needed to accommodate suction through a perforated titanium skin was carried out together with the ducting and systems needed to collect, compress and discharge the suction air. The benefits of reduced aerodynamic drag were weighed against the weight, volume and power requirement penalties of suction system installation in a mission performance and sizing program to assess the net benefits. The study showed a feasibility of achieving significant laminarization of the wing surface by use of a hybrid scheme, leading to an 8.2 percent reduction in the cruise drag. This resulted in an 8.5 percent reduction in the maximum takeoff weight and a 12 percent reduction in the fuel burn after the inclusion of the LFC system installation penalties. Several research needs were identified for a resolution of aerodynamics, structural and systems issues before these potential benefits could be realized in a practical system