Verification Of Behavior Research Articles

Fatigue behavior of Nitinol medical devices under multi-axial non-proportional loads

Nickel-Titanium alloys (Nitinol) are widely used for biomedical applications. Peripheral stents are almost exclusively composed of Nitinol, as its superelasticity is suited for minimally-invasive insertion and durable effect. After crimping and deployment stents undergo cyclic multi-axial loads imposed by vascular and lower-limb motion (e.g. axial compression, bending, and torsion). This complex mechanical environment could lead to metal fatigue and device fracture, with possible severe consequences (e.g. in-stent restenosis). Standard regulations require experimental verification of stent fatigue behaviour for preclinical assessment, but no exact indications are provided to direct the load combination. Moreover, different fatigue criteria were developed for common metals to predict fatigue endurance, but no criteria were specifically defined for the unique thermo-mechanical properties of Nitinol. This study investigated the role of cyclic multi-axial loading conditions on different stent geometries, looking at how they affect the stress/strain distribution along the device and how different criteria may affect the fatigue prediction (e.g. the standard Von Mises alternate approach and other critical plane approaches). Then, a preliminary experimental fatigue campaign was performed in agreement with the numerical simulations in order to compare the numerical predictions with the experimental results. The result suggest that the critical plane approaches are more reliable than the standard Von Mises criterion.

Verification of the emergence in an architecture for multi-robot systems (AMEB)

This article analyzes the emerging behavior of a multi-robot system managed by an architecture structured in three layers: the first provides local support to the robot, manages its processes of action, perception and communication, as well as its behavioral aspect, which considers the reactive, cognitive and social aspects of the robot. In addition, it introduces an affective component that influences its behavior and the way it relates to the environment and to the other individuals in the system, based on an emotional model that takes into account fourArticle history:Received 12 September 2018Accepted 08 November 2018A Gil, pertenece al Laboratorio de Prototipos en la Universidad Nacional Experimental del Tachira y a Tepuy R+D Group. Artificial Intelligence Software Development. Merida, Venezuela (email: agil@unet.edu.ve)basic emotions. The second provides support to the collective processes of the system, based on the concept of emerging coordination. The latter is responsible for knowledge management and learning processes, both individually and collectively, in the system. In this article the metrics are defined to verify the emergency in the system, by means of the use of a method of verification of emergent behaviors based on Fuzzy Cognitive Maps.

Sputter-instigated plasmon-enhanced optical backscattering layer in ultrathin solar cells: Application of GZO in CIGSe material system

Recently, realization of ultrathin solar cells is the area of interest of researchers in the domain of cost-effective photovoltaics. This study demonstrates a novel way of generation of plasmonic features in transparent conducting oxide material in the form of Ga-doped ZnO (GZO) thin films to compensate for the loss of optical absorption due to reduced absorber thickness. Through an extensive analysis of photoelectron spectroscopy, spectroscopic ellipsometry, and field emission scanning electron microscope measurements the evaluation of plasmonic features and correlation of them with various metallic and metal-oxide nanoclusters inside GZO thin film and GZO/CIGSe heterojunction interface are carried out. Moreover, we have thoroughly analyzed the applicability of GZO plasmon enhanced thin film as a backscattering layer based on (a) verification of plasmonic behavior in GZO film (∼150 nm), (b) checking on the sustainability of such plasmonic behavior in ultrathin GZO (∼5 nm) layer, (c) investigation of plasmonic feature at the heterojunction, (d) band offset studies at the plasmon-enhanced-GZO/CIGSe heterojunction, and (e) investigating the electrical performance of the junction to verify the linear behavior and resistivity calculation of the heterojunction.

Potential modelling and verification of bridge superstructures behaviour

During design and analysis process, many simplified technical approaches are routinely used in the application of theories to practice. With the use of modern structural analysis computer programs, the reliable design alternative, providing the most probable response of a bridge structure due to a range of designed loads can be identified. Field measurements should be performed to determine the actual load effect and to verify the applied analytical models. Modelling principles and suggest some guidelines as well as consideration in finite element based structural analysis are illustrated in the paper on selected bridge structures. Measurements for monitoring structural response, collected data are shown using tests carried out on composite bridge superstructures.

VERIFICATION OF BEHAVIOUR OF HUMAN ENAMEL FOR FRACTURE TOUGHNESS DETERMINATION

<p>Enamel is the hardest biological tissue in the human body because of its structure<br />and composition. The structure of interlocking rods enables this biomaterial to resist the stresses of mastication. Unfortunately, enamel is prone to fracture initiation and growth. Determining fracture toughness of enamel is a difficult task. The lack of thickness makes it impossible to prepare samples which could be analyzed by usual methods. Other authors use Vickers indentation fracture test (VIF) to determine fracture toughness of enamel ordinarily. VIF is, however, not generally acceptable.<br />The aim of this study is verification of fracture behaviour of enamel using nanoindentation. In the study the impact of changes of hardness (HIT) and reduced modulus (Er) caused by crack initiation and growth on fracture toughness determination is observed. The next goal is evaluation of loading rate impact.</p>

Preparation, characterization and investigation of sonophotocatalytic activity of thulium titanate/polyaniline nanocomposites in degradation of dyes

Thulium titanate/polyaniline nanocomposites were synthesized to observe the sonophotocatalytic degradation of dyes (widely used as a model pollutant) under ultrasonic irradiation and visible light. Based on our results, the synthesis process can improve sol-gel assisted sonochemical method in the presence of ultrasound and starch. To prepare pure thulium titanate nanostructures, the presence of starch and sonication treatment were concurrently obligatory. Therefore, sol-gel assisted sonochemical method can be used as a successful process for synthesis of thulium titanate nanostructures. According to the BET results, in the presence of ultrasound and starch surface area increased from 9.5305 m2/g to 40.28 m2/g. For verification of photacatalytic behavior of nanoparticles, several factors were studied. The nanocomposites/ultrasonic system showed greater photocatalytic activity for the degradation of Rh B rather than separately treatment of nanocomposites under visible light.

A “direct five-step procedure” for the preliminary seismic design of buildings with added viscous dampers

In the present work a direct procedure for the preliminary seismic design of building structures with added dampers is described which represents the simplification of the so-called “five-step procedure” originally developed in 2010 by some of the authors. The procedure is applicable to yielding frame structures with a generic along-the-height distribution of inter-storey viscous dampers. It is aimed at guiding the structural engineer through the sizing of both viscous dampers and structural elements making use of an equivalent static analysis approach. First, the peak structural response under earthquake excitation is reduced by imposing an overall reduction factor accounting for both the ductility demand and the viscous damping provided by the added dampers. Second, linear damping coefficients are calculated in order to reduce the structural response according to the selected target damping ratio. Then, analytical formulas allow the estimation of peak velocities and forces in the dissipative devices, and an energy criterion is used to identify the non-linear mechanical characteristics of the actual manufactured viscous dampers. Finally, the internal actions in the structural elements are estimated through the envelope of two equivalent static analyses (ESA). At this initial stage of the research, the procedure appears suitable for the preliminary design phase, while correction factors for the higher modes contributions need to be applied to improve its accuracy, especially for high-rise buildings. A numerical verification of the final behaviour of the system by means of non-linear time-history analyses is recommended. An applicative example is finally developed to highlight the soundness of the procedure.

The Quaterniontonic and Octoniontonic Fibonacci Cassini’s Identity: An Historical Investigation with the Maple’s Help

This paper discusses a proposal for exploration and verification of numerical and algebraic behavior correspondingly to Generalized Fibonacci model. Thus, it develops a special attention to the class of Fibonacci quaternions and Fibonacci octonions and with this assumption, the work indicates an investigative and epistemological route, with assistance of software CAS Maple. The advantage of its use can be seen from the algebraic calculation of some Fibonacci’s identities that showed unworkable without the technological resource. Moreover, through an appreciation of some mathematical definitions and recent theorems, we can understand the current evolutionary content of mathematical formulations discussed over this writing. On the other hand, the work does not ignore some historical elements which contributed to the discovery of quaternions by the mathematician William Rowan Hamilton (1805 – 1865). Finally, with the exploration of some simple software’s commands allows the verification and, above all, the comparison of the numerical datas with the theorems formally addressed in some academic articles.

Numerical Simulation and Experimental Analysis of Grease Friction Properties on Textured Surface

This research article is a numerical simulation study and experimental verification of the frictional behaviors of grease lubricated sliding contact under mixed lubrication conditions. The influences of surface texture parameters on the frictional properties were investigated. A numerical simulation model was specifically developed in MatLab which employs the average flow Reynolds equation established on the basis of finite-element analysis to compute the friction coefficient, pressure distribution, and film thickness. The results showed that friction coefficient is largely dependent on texture parameters with higher and lower dimple depths resulting in higher friction coefficient at a fixed dimple density. The sample with texture density of $$T_{\text{d}} = 15\%$$ and texture depth of $$H_{3} = 7$$ μm exhibited the best friction properties experimentally, because it can store more grease and trap wear debris. Through the comparison of the simulated results of the current model with the ring-on-disc experimental results, the validity of the mixed lubrication model was confirmed. However, the lowest friction coefficient occurs at dimple depth of 5 μm and texture density of 10% which is slightly at variance with the experimental results. The simulated results exhibit the reduction of friction for surface texturing and the main mechanism for such an effect may be attributed to the hydrodynamic pressure effect of the surface texturing, which increases the mating gap and reduces probability of asperity contact.

Securing Open Source Clouds Using Models

The widespread adoption of cloud computing has resulted in the proliferation of open source cloud computing frameworks that give more control to enterprises over their data and networks. Though the benefits of open source software are widely recognized, there is a growing concern over their security assurance. Often open source software is a subject of frequent updates. The updates might introduce or remove a variety of features and hence violate security properties of the previous releases. Obviously, a manual inspection of security would be prohibitively slow and inefficient. In this work, we propose an automated approach that can help developers to assure the security of open source cloud framework even in the presence of frequent releases. Our methodology consists of creating a (stateful) wrapper that emulates the usage scenarios with explicit representation of security and functional requirements as contracts. We use a model-driven approach to model REST APIs of KeyStone, an identity service in OpenStack. OpenStack is an open source cloud computing framework providing IaaS. Our models define structural and behavioral properties of Keystone together with its security requirements. We detail the implementation of these models in Django Web Framework and also show how to use the behavioral interfaces to implement a service monitor for the cloud services. This mechanism facilitates verification and validation of functional behavior and security requirement in an automated manner.

Verification of Dynamic Behaviour in Qualitative Molecular Networks Describing Gene Regulation, Signalling and Whole-cell Metabolism

Verification of Dynamic Behaviour in Qualitative Molecular Networks Describing Gene Regulation, Signalling and Whole-cell Metabolism

Sex- and Tissue-Specific Expression Profiles of Odorant Binding Protein and Chemosensory Protein Genes in Bradysia odoriphaga (Diptera: Sciaridae).

Bradysia odoriphaga is an agricultural pest insect affecting the production of Chinese chive and other liliaceous vegetables in China, and it is significantly attracted by sex pheromones and the volatiles derived from host plants. Despite verification of this chemosensory behavior, however, it is still unknown how B. odoriphaga recognizes these volatile compounds on the molecular level. Many of odorant binding proteins (OBPs) and chemosensory proteins (CSPs) play crucial roles in olfactory perception. Here, we identified 49 OBP and 5 CSP genes from the antennae and body transcriptomes of female and male adults of B. odoriphaga, respectively. Sequence alignment and phylogenetic analysis among Dipteran OBPs and CSPs were analyzed. The sex- and tissue-specific expression profiles of 54 putative chemosensory genes among different tissues were investigated by quantitative real-time PCR (qRT-PCR). qRT-PCR analysis results suggested that 22 OBP and 3 CSP genes were enriched in the antennae, indicating they might be essential for detection of general odorants and pheromones. Among these antennae-enriched genes, nine OBPs (BodoOBP2/4/6/8/12/13/20/28/33) were enriched in the male antennae and may play crucial roles in the detection of sex pheromones. Moreover, some OBP and CSP genes were enriched in non-antennae tissues, such as in the legs (BodoOBP3/9/19/21/34/35/38/39/45 and BodoCSP1), wings (BodoOBP17/30/32/37/44), abdomens and thoraxes (BodoOBP29/36), and heads (BodoOBP14/23/31 and BodoCSP2), suggesting that these genes might be involved in olfactory, gustatory, or other physiological processes. Our findings provide a starting point to facilitate functional research of these chemosensory genes in B. odoriphaga at the molecular level.

Sodium chloride as a tracer for hydrodynamic characterization of a shallow maturation pond

Abstract The results of tests with a sodium chloride tracer in a shallow maturation pond in Brazil are presented. The pond – a full-scale effluent treatment unit for around 250 p.e – was 0.80 m deep with a length/width ratio of 4.3:1, and had accumulated sludge for 12 years to about 40% of the total volume. The pond is subject to daily cycles of thermal stratification/destratification, as shown by vertical profiles of temperature, dissolved oxygen, pH and redox potential, and by Computational Fluid Dynamics simulations. Four tracer tests were undertaken. There was a tendency to complete mixing with high dispersion, and daily vertical cycles were evident in all tracer response curves, a distinctive feature of these studies. However, the reliability of the hydraulic retention time calculation, and the short-circuit and mixing indicators, is doubtful, primarily because of the liquor's high density. The study's results enabled practical consideration of the use of saline tracers in pond systems. Sodium chloride acquisition and semi-continuous sensor measurements of effluent concentrations (electrical conductivity) are both easy, but the large amount of salt required (around 300 kg for a 125 m3 pond) and solution density are limiting factors, and can yield unrepresentative results, making this tracer potentially impractical, especially for larger ponds. However, the diurnal cycles of effluent tracer concentration were important in this study and assisted in verification of hydraulic behavior in the liquid column, associated with the stratification and mixing patterns.

Exercise and well-being: Relationships with perceptions of exercise identity-behaviour consistency, affective reactions to exercise and passion

Exercise is strongly linked to well-being, although a better understanding of mechanisms underlying this relationship is needed. Concepts from Identity Theory and the Dualistic Model of Passion show promise in this area but have seldom been examined together. The goal of this exploratory study was to examine the relationships between perceptions of exercise identity-behaviour consistency (IBC), affective reactions to exercise, passion types and general well-being. The participants were 63 active Canadian adult women. Measures consisted of self-report questionnaires administered in the context of a larger study. Analyses involved hierarchical linear regressions and tests of indirect effects. Results showed that controlling for exercise levels, greater perceived consistency (IBC) was associated with higher levels of life satisfaction and vitality. Findings also revealed an indirect effect between extent of IBC and vitality through negative affect as well as an indirect effect on life satisfaction through positive affect. In regards to passion, there were significant interaction effects between passion types (harmonious, obsessive) and the extent of IBC in predicting vitality. For participants showing higher obsessive passion, vitality was poorer as the level of perceived behavioural consistency dropped. The results provide preliminary support in the exercise domain that behavioural verification of an endorsed identity can help promote broader emotional health. Moreover, rigid identification with the exerciser role is tied to needing to exercise to confirm one’s identity and achieve greater well-being. Interventions should be geared towards helping individuals assimilate exercise into their view of themselves in a flexible and compassionate way.

Analysis of Factors of Seismic Damage to Water Air Valve Caused by Water Pressure Change in the Water Pipe and Experimental Verification of Water Pipe Pressure Behavior

Analysis of Factors of Seismic Damage to Water Air Valve Caused by Water Pressure Change in the Water Pipe and Experimental Verification of Water Pipe Pressure Behavior

Erratum to “Theoretical and Experimental Verification of Dynamic Behaviour of a Guided Spline Arbor Circular Saw”

Erratum to “Theoretical and Experimental Verification of Dynamic Behaviour of a Guided Spline Arbor Circular Saw”

Reasoning about Different Orders of Magnitude of Time with smartIflow

In the context of system development design failures can cause immense costs, especially if they remain undetected until very late phases of system integration and test. Therefore it is essential to verify the design concepts systematically before they are actually implemented. Today, model-based techniques are commonly used for the analysis and verification of nominal behavior but not for safety aspects. Unfortunately, current tools still fail to satisfy industrial needs. So, research is needed to overcome limitations in current model-based safety analysis approaches.This paper discusses improvements for one of those approaches called smartIflow. It supports automated reasoning about possible component failures and is especially targeted to early stages of product development. An extension is proposed which allows to control delays of transitions based on order of magnitude values. The extended concepts together with their implementation are then evaluated in a case study of a real system from the railway domain. While limited in size, the study highlights common requirements for the analysis of distributed systems consisting of hard- and software, and illustrates to which extent they are met by the proposed approach.

Load testing of Highway Bridge

New segmental concrete bridge has been built near the city Žilina, aligned on European highway corridor E 50. The bridge is composed of the two separate precast prestressed box girder structure constructed by balanced cantilever method. The total length of both structures is 1042 m. The similar superstructure consists of a total of eighteen continuous spans with main spans of 60.5 m. The construction process, load carrying capacity and monitoring of the bridge has been investigated before the opening of the bridge. The paper presents verification of the structural behaviour of the bridge under static load compared to predicted model for both precast prestressed structures.

Diseño de situaciones de aprendizaje centradas en el aprendizaje estratégico

The educational tendencies in the twentieth century on the teaching and learning scenarios, despite their advances, were dominated and opaque from the teaching praxis by a system of traditions of verification of the human behavior before instructional systems that exalted the hegemony of the teacher on The mental activity of those who learn, this action strengthened a didactic centered on the teaching entity, that cornered the student to be passive, to memorize without meanings and above all to learn away from the reasons with which pertinent learning was in a serious Questioning. Consequently, the master class, the proofs of proof, the dictates, the resolution of abstract problems extracted from the book of foundations prevails in a camouflaged way even today, seventeen years of the twenty-first century. In a responsible manner, the purpose of this research report is to forge reflection scenarios in the subjects that foster the formal and informal education of another subject. The methodology used was the analysis of content from the state of the art of the construct learning situations as an initial search criterion, complemented with the strategic learning approach. Finally, it can be stated that the learning situations recognize the student as an active subject capable of achieving autonomy to learn and of the teacher as mediator of flexible processes that favor knowledge derived from the generic and specific competences contemplated in the respective curricular design or the demand Of the context where the individual performs.

Modelling and verification of bridge behaviour

Obviously several simplifying assumptions are used in a multitude of analytical methods available to structural analysts. Loading tests are habitually necessary, especially in the case of bridge superstructures of unusual conception, with the main purpose to verify calculation model and assumptions of bridge designer as well as suitability of transformation model. To satisfy all required code criteria still more sophisticated analyses are needed. In order to assure the safety under construction of significant bridges, monitoring is also executed to measure and analyse in site data. Also information significant for long term behaviour of structures is being collected. Especially material properties are controlled, rheological effects checked and straining variation recorded. In the paper, quite uncommon bridge superstructures are presented. The computer modelling is discussed and experimental assessment given.