187,235 research outputs found
Generalul Berthelot şi dezrobirea românilor
No full textCosma, Aurel
Generalul Berthelot şi dezrobirea românilor / Aurel Cosma- junior. - Bucureşti : Imprimeriile Independenţa, 1932. - 22 p. ; 24 cm
Alessandro Pratesi (1922-2012)
No full textCosma Rita. Alessandro Pratesi (1922-2012). In: Gazette du livre médiéval, n°59. 2012, fasc. 2. p. 120
Note sur un factum de Cosma Raimondi
No full textDorez Léon. Note sur un factum de Cosma Raimondi. In: Comptes rendus des séances de l'Académie des Inscriptions et Belles-Lettres, 45ᵉ année, N. 5, 1901. p. 622
The Effects of playing the COSMA Cognitive Games in Dementia
No full textBrain Training games are increasingly gaining attention as a non-pharmacological intervention to promote well-being and quality of life in people living with dementia. Herein we present the COSMA software and a pilot study to evaluate its impact on the emotions of people in the spectrum of dementia. The software was created in accordance to the UK National Institute for Health and Care Excellence (NICE) guidelines as a ‘brain-stimulating’ software for use by people with cognitive impairment i.e., mild cognitive impairment (MCI) and early dementia. The pilot study aims to investigate whether the current COSMA game designs have an impact on emotions in people with MCI and early dementia. The emotional evaluation before and after playing COSMA games was carried out using the Positive and Negative Affect Schedule (PANAS). Our findings demonstrated a small, but significant increase in positive emotions (MCI: p= 0.041; early dementia: p= 0.042) and decrease in negative emotions (MCI: p= 0.001; early dementia: p< 0.001). These preliminary results showed that people with MCI and early dementia experienced positive emotions while playing the COSMA games, suggesting that people with cognitive impairment may benefit from using the COSMA software regularly
Photopolymerized AM materials: modelling of the printing process, mechanical behavior and sensitivity analysis
No full textThe physical-chemical processes involved in light-induced polymerization (photopolymerization) are widely exploited in Additive Manufacturing technologies such as Stereolithography and Digital Light Processing. The influence of the AM process parameters on the physical properties of manufactured components has been often investigated through empirical methods based on the trial and error approach, i.e. by collecting and interpreting a large amount of experimental data. However, when specific physical properties are required, accurate modelling of the liquid-solid conversion is necessary. In this work, in order to determine the properties of the resulting material according to the adopted process setup, we present a multi-physics approach to model the physical-chemical transformation taking place in photopolymerization. The role played on the final mechanical properties by the laser light intensity and by its moving speed is considered. Further, the influence of the uncertainty of the process parameters is investigated through a sensitivity analysis. The approach is suitable for investigating the reliability of additively manufactured components as well as for their design according to an optimum printing strategy. From the perspective of making innovative functional materials, the proposed multi-physics model allows tuning the printing process in order to get the desired distribution of mechanical properties
Multiphysics modeling of light-actuated liquid crystal elastomers
No full textLiquid crystalline elastomers (LCEs) represent a promising class of responsive polymers whose
physical properties are peculiar to both fluids and solids. Thanks to their microscale structure
made of elongated rigid molecules (mesogen)—characterized by the capability to reversibly switch from an isotropic to an ordered state—LCEs exhibit a number of remarkable physical effects, such as self-deformation and mechanical actuation triggered by external stimuli. Efficient and physics-based modelling, aimed at designing and optimizing LCE-based devices (such as artificial muscles, deployable structures, soft actuators, etc.), is a fundamental tool to quantitatively describe their mechanical behaviour in real applications. In the present study, we illustrate the multi-physics modelling of light-driven deformation of LCEs, based on the photothermal energy conversion. The role played by the light diffusion and heat transfer within the medium is considered and their effect on the obtainable actuation is studied through numerical simulations based on the multi-physics theory developed
Controlled morphing of architected liquid crystal elastomer elements: modeling and simulations
No full textLiquid crystal elastomers (LCE) are elastomeric materials possessing a network microstructure made of chains with a preferential orientation, induced by mesogen units embedded in the material prior to polymerization. This peculiarity can be harnessed to induce deformation of an LCE element by making its network switch from the preferentially oriented nematic state to the isotropic one, as occurs for instance by rising the temperature above a transition value characteristic of the material. This mechanism can be combined with an architected arrangement of LCE elements, whose nematic orientation and transition temperature are properly differentiated among the different zones constituting the element. In this way, interesting morphing capabilities can be obtained out of an architected elastomer made of LCE portions (ALCE), leading to a morphing structure whose deformation can be activated and precisely tuned by heating up or cooling down the material. In this research, we propose some simple architected LCE elements showing the capability of producing a variety of deformed shapes. A micromechanical theoretical model for LCE is firstly illustrated and several examples of morphing of architected LCE elements, whose mechanical response is obtained through finite element (FE) numerical analyses based on the proposed micromechanical model, are illustrated and critically discussed
COSMA-RF : new intelligent model based on chaos optimized slime mould algorithm and random forest for estimating the peak cutting force of conical picks
No full textSince conical pick cutting is a complex process of multi-factor coupling effects, theoretical model construction for cutting force prediction is a quite difficult task. In this paper, various novel intelligent models based on chaos-optimized slime mould algorithm (COSMA) and random forest (RF) are proposed for this task. In the proposed COSMA-RF methods, the chaos algorithms with the ergodicity and randomness are introduced to chaotically determine the initial position to form a COSMA, and the SMA and COSMA are used to tune the hyperparameters of RF and mean square error are assigned as a fitness function. Consequently, 205 data samples having seven variables (tensile strength of the roc
Code generation for CSM/ECSM models in COSMA environment Generacja kodu programu na podstawie modelu CSM/ECSM w środowisku COSMA /
No full textTyt. z nagłówka.References p. 58-59.Dostępny również w formie drukowanej.STRESZCZENIE: Środowisko COSMA, rozwijane w Instytucie Informatyki Politechniki Warszawskiej, powstało z myślą o weryfikacji modeli (model checking) systemów reaktywnych specyfikowanych przy pomocy automatów CSM (Concurrent State Machines) jak i ich rozszerzonej wersji (ECSM - Extended CSM). Rozszerzenie CSM o złożone struktury danych, atrybuty związane z przejściami i stanami oraz możliwość bezpośredniego użycia kody w C/C++ powodują, że model wyrażony w ECSM nie może być formalnie weryfikowany, a jedynie stanowić krok pośredni przy generacji kodu. W takim podejściu model CSM reprezentuje sterowanie i komunikację pomiędzy modułami systemu, podczas gdy ECSM - dane i szczegóły przetwarzania. Artykuł omawia generację kodu z modelu ECSM zilustrowaną przykładem. SŁOWA KLUCZOWE: weryfikacja, COSMA, generacja kodu, CSM, ECSM, automaty skończenie stanowe. ABSTRACT: The COSMA software environment, developed in the Institute of Computer Science, WUT, was designed primarily for model checking of reactive systems specified in terms of Concurrent State Machines (CSM). However, COSMA supports also Extended CSM (ECSM). The extensions allow for using complex data types and pieces of C/C++ code, attributed to CSM states and/or transitions. Because of these extensions, ECSM models cannot be verifed by model checking, but they can be used as an intermediate step in code generation. The underlying CSM represent then the flow of control within cooperating components and the communication among them while the extensions specify the data structures and the details of their processing. The paper discusses the code generation from ECSM diagrams. The approach is illustrated with an example. KEYWORDS: model checking, COSMA, code generation, CSM, ECSM, FSM
Proposing Chitosan/Snail Slime Blended Films As Sustainable Functional Masks/Patches for Cosmetics and Biomedical Applications
No full textenvironmental impact is needed worldwide in different fields, particularly in cosmetics and biomedicine. For this purpose, our research focused the attention on realizing Chitosan-based films blended with Snail Slime to develop facial beauty masks or functional patches for potential cosmetics and biomedical applications. After preliminarily investigating their morphology, a physical and chemical characterization was also performed by attaining SEM, UV-Vis, ATR-FTIR, profilometer analyses, and Water Vapor Transmission Rate measurements, evidencing a quite uniform distribution of the snail mucus inside the chitosan films. As a result, compacted and strongly cross-linked structures were observed. XRD analyses demonstrated their amorphous nature. For assessing their stability in water medium, the swelling measurements were acquired, showing the effect of pH, ionic strength, and temperature. The antioxidant features were finally investigated by means of the ABTS assay, resulting in a boosted activity when the snail slime added amount was increased, occurring to be as dose dependent. [1] For further confirming these findings, the oxidation of a sulphur nucleoside, the 4-thiotymidine, was monitored overtime; as a result, its H2O2-induced degradation was prevented when increasing the Snail Slime amount. Work is in progress for testing in-vitro Chitosan-based blended films’ antioxidant, as well as anti-inflammatory properties, with the aim also to assess their potential effect on improving wound healing, thanks to the snail slime components content. [1, 2] Furthermore, Chitosan/Snail Slime blended films’ sunscreen, moisturizing, and skin-lightening properties will be explored, for making them suitable also as potential cosmetic multifunctional formulations. [3
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