A Multidimensional scaling perspective of Rostow's forecasts with the Track-record (1960s-2011) of "pioneers" and "latecomers"

Proceedings of the 12th Conference on Dynamical Systems -Theory and Applications

Bipedal Locomotion: A Fractional CPG for Generating Patterns

Proceedings of the 10th Conference on Dynamical Systems Theory and Applications

Fractional Dynamics Representation in the Pseudo Phase Plane

Proceedings of the 10th Conference on Dynamical Systems Theory and Applications

Application of Fractional Calculus in Mechatronics

Fractional Calculus (FC) goes back to the beginning of the theory of differential calculus. Nevertheless, the application of FC just emerged in the last two decades. In the field of dynamical systems theory some work has been carried out but the proposed models and algorithms are still in a preliminary stage of establishment. Having these ideas in mind, the paper discusses a FC perspective in the study of the dynamics and control of mechanical systems.

Biomimetic strategies to engineer mineralised human tissues

In the last few years, many reports have been describing promising biocompatible and biodegradable materials that can mimic in a certain extent the multidimensional hierarchical structure of bone, while are also capable of releasing bioactive agents or drugs in a controlled manner. Despite these great advances, new developments in the design and fabrication technologies are required to address the need to engineer suitable biomimetic materials in order tune cells functions, i.e. enhance cell-biomaterial interactions, and promote cell adhesion, proliferation, and differentiation ability. Scaffolds, hydrogels, fibres and composite materials are the most commonly used as biomimetics for bone tissue engineering. Dynamic systems such as bioreactors have also been attracting great deal of attention as it allows developing a wide range of novel in vitro strategies for the homogeneous coating of scaffolds and prosthesis with ceramics, and production of biomimetic constructs, prior its implantation in the body. Herein, it is overviewed the biomimetic strategies for bone tissue engineering, recent developments and future trends. Conventional and more recent processing methodologies are also described.

Characterization of an in vitro fed-batch model to obtain cells released from S. epidermidis biofilms

Both dynamic and fed-batch systems have been used for the study of biofilms. Dynamic systems, whose hallmark is the presence of continuous flow, have been considered the most appropriate for the study of the last stage of the biofilm lifecycle: biofilm disassembly. However, fed-batch is still the most used system in the biofilm research field. Hence, we have used a fed-batch system to collect cells released from Staphylococcus epidermidis biofilms, one of the most important etiological agents of medical device-associated biofilm infections. Herein, we showed that using this model it was possible to collect cells released from biofilms formed by 12 different S. epidermidis clinical and commensal isolates. In addition, our data indicated that biofilm disassembly occurred by both passive and active mechanisms, although the last occurred to a lesser extent. Moreover, it was observed that S. epidermidis biofilm-released cells presented higher tolerance to vancomycin and tetracycline, as well as a particular gene expression phenotype when compared with either biofilm or planktonic cells. Using this model, biofilm-released cells phenotype and their interaction with the host immune system could be studied in more detail, which could help providing significant insights into the pathophysiology of biofilm-related infections.

Expert supervision based on cases

The paper focuses on taking advantage of large amounts of data that are systematically stored in plants (by means of SCADA systems), but not exploited enough in order to achieve supervisory goals (fault detection, diagnosis and reconfiguration). The methodology of case base reasoning (CBR) is proposed to perform supervisory tasks in industrial processes by re-using the stored data. The goal is to take advantage of experiences, registered in a suitable structure as cam, avoiding the tedious task of knowledge acquisition and representation needed by other reasoning techniques as expert systems. An outlook of CBR terminology and basic concepts are presented. The adaptation of CBR in performing expert supervisory tasks, taking into account the particularities and difficulties derived from dynamic systems, is discussed. A special interest is focused in proposing a general case definition suitable for supervisory tasks. Finally, this structure and the whole methodology is tested in a application example for monitoring a real drier chamber

Identifying a mutual attending frame: a pilot study of gaze interactions between therapist and couple.

Refering to systems theory, we identify a supraindividual property in interactions between therapist and couple. We use gaze directions to describe the partners' behaviors and label this property the "mutual attending frame." We propose a procedure to observe triadic interactions in a consultation setting and a method to measure mutual attending. The method is illustrated by the data analysis of two triads contrasted on measures of therapeutic alliance. We discuss the potential of this method for the description of the interactive aspects of the therapeutic alliance.

Implicit methods for qualitative modeling of gene regulatory networks.

Advancements in high-throughput technologies to measure increasingly complex biological phenomena at the genomic level are rapidly changing the face of biological research from the single-gene single-protein experimental approach to studying the behavior of a gene in the context of the entire genome (and proteome). This shift in research methodologies has resulted in a new field of network biology that deals with modeling cellular behavior in terms of network structures such as signaling pathways and gene regulatory networks. In these networks, different biological entities such as genes, proteins, and metabolites interact with each other, giving rise to a dynamical system. Even though there exists a mature field of dynamical systems theory to model such network structures, some technical challenges are unique to biology such as the inability to measure precise kinetic information on gene-gene or gene-protein interactions and the need to model increasingly large networks comprising thousands of nodes. These challenges have renewed interest in developing new computational techniques for modeling complex biological systems. This chapter presents a modeling framework based on Boolean algebra and finite-state machines that are reminiscent of the approach used for digital circuit synthesis and simulation in the field of very-large-scale integration (VLSI). The proposed formalism enables a common mathematical framework to develop computational techniques for modeling different aspects of the regulatory networks such as steady-state behavior, stochasticity, and gene perturbation experiments.

Yrityksen prosessit dynaamisten kyvykkyyksien lähteenä

Pysyvän kilpailuedun saavuttaminen on jokaisen yrityksen strategisen suunnittelun keskeinen tavoite. Monet tunnetut tutkijat ovat suunnanneet strategista johtamista omilla teorioillaan ja tuloksillaan. Tutkimuksissa on havaittu että perinteisillä strategisen johtamisen teorioilla ei voida selittää nykyisin nopeasti muuttuvassa maailmassa toimivien yritysten menestystä. Menestyksen takaa löytyviä tekijöitä kutsutaan yrityksen dynaamisiksi tekijöiksi. Yhtenä merkittävänä dynaamisena tekijänä ovat tulleet esille yrityksen prosessit. Tutkimuksessa on yhdistetty kaksi asiaa samaan tarkastelukehikkoon. Olen tuonut siihen toisaalta yrityksen prosessit, jotka ovat alan parhaiden käytäntöjen mukaiset. Toisaalta on esitetty teoria dynaamisista kyvykkyyksistä, joiden oletetaan ilmentyvän yrityksen prosesseissa. Tässä työssä tarkastellaan yritysten dynaamisista kyvykkyyksistä vain prosesseja.Työn tarkoituksena on löytää vastauksia seuraaviin tutkimuskysymyksiin: Mitkä ovat yrityksen prosessien kautta saavutettavat dynaamiset kyvykkyydet? Voiko yritys saavuttaa ja säilyttää kilpailuetua toteuttaessaan prosessinsa alan parhaiden käytäntöjen mukaan? Voidaanko tunnistetuille dynaamisille kyvykkyyksille rakentaa mallia niiden mittaamiseen?Tutkimuskysymyksiin olen hakenut vastausta esimerkkiyrityksen prosessikehityshankkeen kautta. Tavoitteena on ollut tunnistaa prosessikehityksen takaa mahdolliset yrityksen dynaamiset kyvykkyydet ja siten nimetä niitä yrityksen kilpailuedun tekijöiksi. Tutkimuskohteena olevaan ICT-alan yritykseen kohdistuu yhä suurempia tuottavuuteen ja laatuun liittyviä vaatimuksia. Yhtenä ratkaisuna vastata näihin vaateisiin ovat yritykset lähteneet kehittämään niiden prosesseja. ICT-palveluyritysten toimintaan tukeva viitekehys on ITIL. Viitekehykseen on kerätty useamman yrityksen ja organisaation kokemukset palveluiden tehokkaasta tuottamisesta. ITIL – viitekehys on ollut perustana vuonna 2005 julkaistulle ISO/IEC 20000-1:2005 palveluiden johtamisen standardille. Tutkimuksen perusteella voidaan sanoa, että määrämuotoiset prosessit lisäävät yritysten ketteryyttä mukautua muutoksiin ja siten myös niiden dynaamiset kyvykkyydet ovat lisääntyneet.

Diferencias en la dimensionalidad electroencefalograma entre vigilia y sueño profundo

Differences in dimensionality of electroencephalogram during awake and deeper sleep stages. The nonlinear dynamical systems theory provides some tools for the analysis of electroencephalogram (EEG) at different sleep stages. Its use could allow the automatic monitoring of the states of the sleep and it would also contribute an explanatory level of the differences between stages. The goal of the present paper is to address this type of analysis, focusing on the most different stages. Estimations of dimensionality were compared when six subjects were awake and in a deep sleep stage. Greater dimensionality involves more complexity because the system receives more external influences. If this dimensionality is maximum, we can consider that the time series is a noisy one. A smaller dimensionality involves lower complexity because the system receives fewer inputs. We hypothesized that we would find greater dimensionality when subjects were awake than in a deep sleep stage. Results show a noisy time series during the awake stage, whereas in the sleep stage, dimensionality is smaller, confirming our hypothesis. This result is similar to the findings reached previously by other authors.

SQualTrack: A Tool for Robust Fault Detection

One of the techniques used to detect faults in dynamic systems is analytical redundancy. An important difficulty in applying this technique to real systems is dealing with the uncertainties associated with the system itself and with the measurements. In this paper, this uncertainty is taken into account by the use of intervals for the parameters of the model and for the measurements. The method that is proposed in this paper checks the consistency between the system's behavior, obtained from the measurements, and the model's behavior; if they are inconsistent, then there is a fault. The problem of detecting faults is stated as a quantified real constraint satisfaction problem, which can be solved using the modal interval analysis (MIA). MIA is used because it provides powerful tools to extend the calculations over real functions to intervals. To improve the results of the detection of the faults, the simultaneous use of several sliding time windows is proposed. The result of implementing this method is semiqualitative tracking (SQualTrack), a fault-detection tool that is robust in the sense that it does not generate false alarms, i.e., if there are false alarms, they indicate either that the interval model does not represent the system adequately or that the interval measurements do not represent the true values of the variables adequately. SQualTrack is currently being used to detect faults in real processes. Some of these applications using real data have been developed within the European project advanced decision support system for chemical/petrochemical manufacturing processes and are also described in this paper

Lipídios como indicadores de fontes e distribuição de matéria orgânica particulada em um complexo estuarino-lagunar tropical (Mundaú-Manguaba, AL)

Fatty acids, alcohols and sterols were considered as markers of the source and distribution of particulate organic matter during the dry season in the Mundaú-Manguaba estuarine-lagoon system, NE Brazil. Lipid composition showed an overwhelming influence of autochthonous sources of organic matter in all system´s compartments, including the probable occurrence of algal blooms in specific areas. On the other hand, contamination by sewage was restricted to Mundaú lagoon. This scenario differed from known conditions observed in the wet season, illustrating the usefulness of the lipid biomarker approach for the characterization of other complex and dynamic systems in the Brazilian coastal zone.