Aura Mihai - Academia.edu (original) (raw)

Papers by Aura Mihai

Leather and Footwear Journal

Nowadays, one of the most critical health problems among young people is obesity. Because teenage... more Nowadays, one of the most critical health problems among young people is obesity. Because teenagers are still in the growing process, the foot shape and plantar footprints are very important to be analysed and potential problems to be identified. Young adulthood is a risky period for the development of obesity. This study aims to analyse the plantar footprints, the biomechanical parameters obtained through plantar pressure measurements, and the 3D shape of the foot and anthropometrical parameters obtained from scanning. By comparing the results, both feet have been demonstrated to be high arched, as well as high pressures were identified and differences from left to the right foot. With these results, prophylactic footwear and components can be designed, adapted to the subject’s feet.

Leather and Footwear Journal, Jun 30, 2021

The biomechanical analysis allows to understand the normal and pathological gait, the mechanics o... more The biomechanical analysis allows to understand the normal and pathological gait, the mechanics of neuromuscular control, and last but not least, allows the visualisation of the effects of footwear on human gait or feet. Biomechanical analyses are very important for the footwear development process, as they can identify the incorrect loading of the foot or the incorrect gait pattern, thus avoiding the occurrence of deformations. This paper aims to create an average representative model of barefoot loading based on an extended group of participants by applying an optimal procedure for measuring biomechanical parameters. The variation of four basic biomechanical parameters, namely force, pressure, contact time and contact area, was measured using a pressure platform and a specialised software system. The data was collected from 32 healthy females, without particularities regarding foot health and the practice of performance sports, aged between 18 and 30 years, divided into three size groups-36, 37 and 38. The T-Student test was applied to verify if there are significant differences between the left and right foot. Statistical indicators for each parameter were calculated, in order to characterize and establish the degree of variation of the obtained values, as follows: mean, standard deviation, minimum and maximum values, the amplitude of variation and coefficient of variation (CV). The study results confirm that the obtained mean values can be used as input data to load the foot and perform virtual simulations of footwear products. KEYWORDS: foot, biomechanics, normal gait PARAMETRII BIOMECANICI CARE CARACTERIZEAZĂ PICIORUL ÎN TIMPUL MERSULUI NORMAL REZUMAT. Analiza biomecanică permite înțelegerea mersului normal și patologic, mecanica controlului neuromuscular și, nu în ultimul rând, permite vizualizarea efectelor încălțămintei asupra mersului uman și a picioarelor. Analizele biomecanice sunt foarte importante pentru procesul de dezvoltare a încălțămintei, deoarece permit identificarea încărcării incorecte a piciorului sau depistarea modelului incorect al mersului, evitând astfel apariția deformațiilor. Această lucrare are drept scop crearea unui model mediu reprezentativ de încărcare a piciorului desculț bazat pe un grup extins de participanți prin aplicarea unei proceduri optime pentru măsurarea parametrilor biomecanici. Variația a patru parametri biomecanici de bază, și anume forța, presiunea, timpul de contact și suprafața de contact, a fost măsurată utilizând o platformă de presiuni plantare și un sistem software specializat. Studiul s-a realizat pentru un eșantion de 32 de persoane de sex feminin, fără anumite particularități referitoare la starea de sănătate a picioarelor și practicarea sporturilor de performanță, cu vârsta cuprinsă între 18-30 de ani, împărțite pe 3 grupuri de mărimi, respectiv 36, 37 și 38 în sistem francez. Testul T-Student a fost aplicat pentru a verifica dacă există diferențe semnificative între valorile pentru piciorul stâng și cel drept. Au fost calculați indicatorii statistici pentru fiecare parametru analizat în vederea caracterizării și stabilirii gradului de variație a valorilor obținute, și anume: media aritmetică, abaterea standard, minimul, maximul, amplitudinea variației și coeficientul de variație. Rezultatele studiului confirmă faptul că valorile medii obținute pot fi utilizate ca date de intrare pentru a încărca piciorul și a simula comportamentul încălțămintei. CUVINTE CHEIE: picior, biomecanica mersului, mers normal LES PARAMÈTRES BIOMÉCANIQUES QUI CARACTÉRISENT LE PIED PENDANT LA DÉMARCHE NORMALE RÉSUMÉ. L'analyse biomécanique permet de comprendre la démarche normale et pathologique, la mécanique du contrôle neuromusculaire et, enfin et surtout, permet de visualiser les effets des chaussures sur la démarche et les pieds humains. Les analyses biomécaniques sont très importantes pour le processus de développement de la chaussure, car elles permettent l'identification de la charge incorrecte du pied ou la détection du modèle de démarche incorrect, évitant ainsi l'apparition de déformations. Cet article vise à créer un modèle moyen représentatif de la charge des pieds nus basé sur un groupe étendu de participants en appliquant une procédure optimale pour mesurer les paramètres biomécaniques. La variation de quatre paramètres biomécaniques de base, à savoir la force, la pression, le temps de contact et la surface de contact, a été mesurée à l'aide d'une plate-forme de pression plantaire et d'un système logiciel spécialisé. L'étude a été menée pour un échantillon de 32 femmes, sans aucune particularité concernant la santé des pieds et les sports de performance, âgées de 18 à 30 ans, réparties en 3 groupes de taille, respectivement 36, 37 et 38 dans le système français. Le test T-Student a été appliqué pour voir s'il y avait des différences significatives entre les valeurs pour le pied gauche et le pied droit. Des indicateurs statistiques ont été calculés pour chaque paramètre analysé afin de caractériser et d'établir le degré de variation des valeurs obtenues, à savoir : la moyenne arithmétique, l'écart type, le minimum, le maximum, l'amplitude de variation et le coefficient de variation. Les résultats de l'étude confirment que les valeurs moyennes obtenues peuvent être utilisées comme données d'entrée pour charger le pied et simuler le comportement de la chaussure. MOTS CLÉS: pied, biomécanique de la démarche, démarche normale

Potenciais de Esquemas de Aprendizagem com Base no Trabalho orientados por Currículos inseridos e... more Potenciais de Esquemas de Aprendizagem com Base no Trabalho orientados por Currículos inseridos em Sistemas de Educação/Formação Profissional na Roménia e em Portugal

Potentiale von curricular gesteuertem Lernen im Prozess der Arbeit in den schulbasierten Berufsbi... more Potentiale von curricular gesteuertem Lernen im Prozess der Arbeit in den schulbasierten Berufsbildungssystemen in Portugal und Rumänien

The International Conference on Advanced Materials and Systems, 2016

This study was conducted to establish a set of major causal factors that influence foot pathologi... more This study was conducted to establish a set of major causal factors that influence foot pathologies and deformities for the elderly, analyzing variables such as weight and height of subjects. The study included 100 elderly female volunteers weighing between 50 and 112 kg and measuring between 148 and 184 cm in height. The sampling method used was the non-probabilistic one, based on a mixture of Henry's sampling types, using the questionnaire, and testing was conducted using measurement and observation instruments. Subjects participated in biomechanical measurements using AMTI's AccuGait System force platform, performed in Bucharest for a period of three weeks. The results show a strong correlation among the tested variables. Weight proves to be one of the most important causative factors, as there were statistically significant correlations between it and most biomechanical parameters measured. Thus, it can be concluded that as the elderly grow in weight, they undergo significant changes in biomechanical parameters, reflected in foot deformities and pathologies.

Recently virtual training has been regarded as an innovation notably for vocational training. The... more Recently virtual training has been regarded as an innovation notably for vocational training. There have appeared numerous virtual learning environments and various approaches and tools to this end. The focus of "virtual learning" is in fact is on computer technology and education. The objective of this paper is to present a virtual training environment designed for shoe design training in the framework of EU LLP projects: Virtual Training Centre for Shoe Design (VTC-SHOE). The aim of the project is to implement shoe design training content (at elementary and intermediate level) into a virtually designed and served training centre, which is accessible over Internet, e-learning will be realised as an innovation in this field. Virtual Training Centre for Shoe Design will be set up on the Internet to supply training (at elementary and intermediate level) for shoe design. A virtual space, a shoe design training portal on the Internet which will allow the constant sharing of e-learning based shoe design training material so as to foster the further development of e-learning based shoe design educational contents will be created. The equipment, methods, curriculum and techniques currently used in shoe design training by partners will be observed, collected and evaluated. The selected materials will be used to create a new and efficient curriculum. This curriculum will be the core of target virtual training activity to form the curriculum (at elementary and intermediate level). According to this curriculum, an interactive teaching program will be developed and put into a website to form a virtual training centre.

High Performance Polymers, 2011

New nanocomposite films were prepared from a dispersion of organically modified montmorillonite a... more New nanocomposite films were prepared from a dispersion of organically modified montmorillonite as the filler and flexible polyurethane as the matrix. The polyurethanes containing a small amount of carboxylic groups were synthesized from 4,4′-diphenylmethane diisocyanate (MDI), 1,4-butanediol (1,4-BD), and poly(tetramethyleneoxide diol) (PTMO) of 1000 average molecular weight, the carboxylic unit being included by means of dimethylol propionic acid (DMPA) or

Applied Clay Science, 2010

Abstract Polyurethane (PU)/organo-montmorillonite nanocomposites were prepared by in situ polymer... more Abstract Polyurethane (PU)/organo-montmorillonite nanocomposites were prepared by in situ polymerization of toluene diisocyanate and butanediol in the presence of different contents of organo-montmorillonite (9–18 mass%). Organo-montmorillonite were prepared by an ion exchange process of sodium montmorillonite with –NH3+ groups in polyoxyalkylene amine hydrochloride with two different molecular masses of 403 and 5000. To change the degree of surface modification, sodium montmorillonite was reacted with polyoxyalkylene amine hydrochloride in equivalent ratios (1:1 and 1:2). Dimethyl formamide (DMF) was used as a swelling agent for the prepared organo-montmorillonite. Different nanocomposite structures, depending on the molecular mass of the polyoxyalkylene and the degree of surface modification of montmorillonite were studied. The results of X-ray analysis and transmission electron microscopy showed that the organo-montmorillonite with polyoxyalkylene of higher molecular mass (T5000) produced the exfoliated PU nanocomposites; (T403), led to an intercalated structure. Nanocomposites exhibited lower water adsorption values and higher thermal stability than that of pure PU0. In addition, the hardness of the nanocomposites was measured.

Materials

This paper aimed to define two critical mechanical properties of leather—Young’s modulus and Pois... more This paper aimed to define two critical mechanical properties of leather—Young’s modulus and Poisson ratio—essential to the virtual simulation of the behaviour of the footwear uppers against the manufacturing operations of stitching and perforating. The following technological aspects were considered to analyse the materials from manufacturing conditions point of view: the number of layers (one layer and two layers), the nature of the materials used for uppers subgroups (calfskin-outer upper, sheep leather-lining, polyester knitted fabric-lining), the overlapping width in the stitching area, the number of parallel stitches (single stitch and double stitch), the punching interval and the type of perforations (simple and with eyelets), resulting in nine kinds of samples. Furthermore, the elasticity (Young’s modulus) and lateral contraction (Poisson’s ratio) were calculated during the tensile strength analysis performed on the SATRA STM 466 equipment. Both mechanical parameters are ess...

International Symposium "Technical Textiles - Present and Future", 2022

The TCLF sectors' competitiveness in Romania is affected by several factors that are not necessar... more The TCLF sectors' competitiveness in Romania is affected by several factors that are not necessarily linked to the European ones, such as transportation infrastructure, regional disparities, labour mobility, capacity for innovation of the companies, legislative changes. However, concerning the external factors of influence at the macroeconomic level, and based on the interviews conducted in the framework of the Skills4Smart project in 2019 on 24 companies in the TCLF sector in Romania, the following drivers of change are analysed: A new customer, Demographic change and Environmental change, Technological change, Regulation&Governance, Economic&Globalization, Value&Identities.

INTED2022 Proceedings, 2022

Potentials of Curricula-driven Work-based Learning Schemes within School-based VET Systems of Rom... more Potentials of Curricula-driven Work-based Learning Schemes within School-based VET Systems of Romania and Portugal

All in-text references underlined in blue are linked to publications on ResearchGate, letting you... more All in-text references underlined in blue are linked to publications on ResearchGate, letting you access and read them immediately.

Tekstil Ve Konfeksiyon, 2016

Diyabet ve artrit dunyada en sik gorulen kronik hastaliklardir. Diyabet, kalp krizi, inme, ayak p... more Diyabet ve artrit dunyada en sik gorulen kronik hastaliklardir. Diyabet, kalp krizi, inme, ayak problemleri, iktidarsizlik, bobrek ve goz gibi vucudun bircok uzvunda hasara neden olabilen bir hastaliktir. Diyabetli kisilerin genellikle ayaklari ile sorunlari vardir. Sorunun bir bolumunu diyabetli kisilerin ayaklarinda his kaybi olusmasindan oturu, su toplama veya yara olusumu gec algilamalari olusturmaktadir ve yaralarin tedavi edilmemesi durumunda ulser ile sonuclanabilmektedir. Uygun ayakkabinin secimi diyabet ve artrit hastalari icin buyuk onem tasimaktadir. Bu calismada, diyabet ve artritten kaynaklanan lokomotor bozukluklara sahip hastalarin kullanacagi ayakkabi astarlari icin uygun fonksiyonel orme kumaslarin performans ve fiziksel ozelliklerine kumas yapisi ve iplik tipinin etkisinin incelenmesi amaclanmaktadir. Ilgili ayakkabi standardina uygun olarak optimum parametrelere sahip kumaslarin secimi icin, kumaslarin kopma mukavemeti, kopma uzamasi, su buhari gecirgenligi...

Contemporary furniture ought to provide high level of sensorial and thermal comfort to its users,... more Contemporary furniture ought to provide high level of sensorial and thermal comfort to its users, both in dry state and after partial wetting due to increased air humidity and sweating of the seated person. This paper aims to experimentally determine thermal resistance, thermal conductivity and thermal contact feeling (thermal absorptivity) of 10 cowhide and 5 artificial leather samples used for upholstered furniture. The measurements involve samples in both dry and wet state. It was found that the increased relative moisture of the samples caused their thermal resistance to decrease rapidly, intensifying the feeling of coolness.

The aim of this study was to develop principles of 3D modelling of lasts used to obtain special f... more The aim of this study was to develop principles of 3D modelling of lasts used to obtain special footwear for patients with locomotion disabilities caused by arthritis. The design process and manufacture process of a personalized last are the first steps in achieving the right type of footwear for patients with arthritis. The footwear shape and dimensions are influenced by the last’s shape and dimensions. A last that is designed without a scientific basis, without considering the consumer’s foot individual conformation, will lead to an unsuitable footwear product. The compatibility between the foot and the last represents the key element for this kind of activity. Whatever method is used, the shape of the last is given by the shape of the foot and its dimensions (length, widths and girths). These foot dimensions are modified and transformed into last’s dimensions using 3D modelling software. The advantage of 3D modelling procedure is that it allows us to interactively visualize and t...

PLANTAR FOOTPRINTS ANALYSIS – CASE STUDY (PART 1) ABSTRACT. This study aims to analyze the planta... more PLANTAR FOOTPRINTS ANALYSIS – CASE STUDY (PART 1) ABSTRACT. This study aims to analyze the plantar footprints based on biomechanical parameters obtained through plantar pressure measurements and to present an easy to use methodology for establishing the foot type in order to further suggest orthopaedic devices, such as customized soles and insoles. Using the RSScan pressure plate and the Footscan software, fine observations both on foot and on repartition of foot pressures are made. By analyzing the maximum pressures