Analysis of temperature time-series: embedding dynamics into the MDS method

Global warming and the associated climate changes are being the subject of intensive research due to their major impact on social, economic and health aspects of the human life. Surface temperature time-series characterise Earth as a slow dynamics spatiotemporal system, evidencing long memory behaviour, typical of fractional order systems. Such phenomena are difficult to model and analyse, demanding for alternative approaches. This paper studies the complex correlations between global temperature time-series using the Multidimensional scaling (MDS) approach. MDS provides a graphical representation of the pattern of climatic similarities between regions around the globe. The similarities are quantified through two mathematical indices that correlate the monthly average temperatures observed in meteorological stations, over a given period of time. Furthermore, time dynamics is analysed by performing the MDS analysis over slices sampling the time series. MDS generates maps describing the stations’ locus in the perspective that, if they are perceived to be similar to each other, then they are placed on the map forming clusters. We show that MDS provides an intuitive and useful visual representation of the complex relationships that are present among temperature time-series, which are not perceived on traditional geographic maps. Moreover, MDS avoids sensitivity to the irregular distribution density of the meteorological stations.

Analysis of UV spectral bands using multidimensional scaling

This study describes the change of the ultraviolet spectral bands starting from 0.1 to 5.0 nm slit width in the spectral range of 200–400 nm. The analysis of the spectral bands is carried out by using the multidimensional scaling (MDS) approach to reach the latent spectral background. This approach indicates that 0.1 nm slit width gives higher-order noise together with better spectral details. Thus, 5.0 nm slit width possesses the higher peak amplitude and lower-order noise together with poor spectral details. In the above-mentioned conditions, the main problem is to find the relationship between the spectral band properties and the slit width. For this aim, the MDS tool is to used recognize the hidden information of the ultraviolet spectra of sildenafil citrate by using a ShimadzuUV–VIS 2550, which is in theworld the best double monochromator instrument. In this study, the proposed mathematical approach gives the rich findings for the efficient use of the spectrophotometer in the qualitative and quantitative studies.

Multidimensional scaling analysis of fractional systems

This paper investigates the use of multidimensional scaling in the evaluation of fractional system. Several algorithms are analysed based on the time response of the closed loop system under the action of a reference step input signal. Two alternative performance indices, based on the time and frequency domains, are tested. The numerical experiments demonstrate the feasibility of the proposed visualization method.

Practical aspects of slot-based task- splitting dispatching in its schedulability analysis

Consider the problem of scheduling a set of sporadic tasks on a multiprocessor system to meet deadlines using a tasksplitting scheduling algorithm. Task-splitting (also called semipartitioning) scheduling algorithms assign most tasks to just one processor but a few tasks are assigned to two or more processors, and they are dispatched in a way that ensures that a task never executes on two or more processors simultaneously. A certain type of task-splitting algorithms, called slot-based task-splitting, is of particular interest because of its ability to schedule tasks at high processor utilizations. We present a new schedulability analysis for slot-based task-splitting scheduling algorithms that takes the overhead into account and also a new task assignment algorithm.

Analysis of stock market indices through multidimensional scaling

We propose a graphical method to visualize possible time-varying correlations between fifteen stock market values. The method is useful for observing stable or emerging clusters of stock markets with similar behaviour. The graphs, originated from applying multidimensional scaling techniques (MDS), may also guide the construction of multivariate econometric models.

Is multidimensional scaling suitable for mapping the input respiratory impedance in subjects and patients?

This paper presents the application of multidimensional scaling (MDS) analysis to data emerging from noninvasive lung function tests, namely the input respiratory impedance. The aim is to obtain a geometrical mapping of the diseases in a 3D space representation, allowing analysis of (dis)similarities between subjects within the same pathology groups, as well as between the various groups. The adult patient groups investigated were healthy, diagnosed chronic obstructive pulmonary disease (COPD) and diagnosed kyphoscoliosis, respectively. The children patient groups were healthy, asthma and cystic fibrosis. The results suggest that MDS can be successfully employed for mapping purposes of restrictive (kyphoscoliosis) and obstructive (COPD) pathologies. Hence, MDS tools can be further examined to define clear limits between pools of patients for clinical classification, and used as a training aid for medical traineeship.

Analysis of financial data series using fractional Fourier transform and multidimensional scaling

The goal of this study is the analysis of the dynamical properties of financial data series from worldwide stock market indexes during the period 2000–2009. We analyze, under a regional criterium, ten main indexes at a daily time horizon. The methods and algorithms that have been explored for the description of dynamical phenomena become an effective background in the analysis of economical data. We start by applying the classical concepts of signal analysis, fractional Fourier transform, and methods of fractional calculus. In a second phase we adopt the multidimensional scaling approach. Stock market indexes are examples of complex interacting systems for which a huge amount of data exists. Therefore, these indexes, viewed from a different perspectives, lead to new classification patterns.

Identifying economic periods and crisis with the multidimensional scaling

This paper applied MDS and Fourier transform to analyze different periods of the business cycle. With such purpose, four important stock market indexes (Dow Jones, Nasdaq, NYSE, S&P500) were studied over time. The analysis under the lens of the Fourier transform showed that the indexes have characteristics similar to those of fractional noise. By the other side, the analysis under the MDS lens identified patterns in the stock markets specific to each economic expansion period. Although the identification of patterns characteristic to each expansion period is interesting to practitioners (even if only in a posteriori fashion), further research should explore the meaning of such regularities and target to find a method to estimate future crisis.

Multidimensional scaling visualization of earthquake phenomena

Earthquakes are associated with negative events, such as large number of casualties, destruction of buildings and infrastructures, or emergence of tsunamis. In this paper, we apply the Multidimensional Scaling (MDS) analysis to earthquake data. MDS is a set of techniques that produce spatial or geometric representations of complex objects, such that, objects perceived to be similar/distinct in some sense are placed nearby/distant on the MDS maps. The interpretation of the charts is based on the resulting clusters since MDS produces a different locus for each similarity measure. In this study, over three million seismic occurrences, covering the period from January 1, 1904 up to March 14, 2012 are analyzed. The events, characterized by their magnitude and spatiotemporal distributions, are divided into groups, either according to the Flinn–Engdahl seismic regions of Earth or using a rectangular grid based in latitude and longitude coordinates. Space-time and Space-frequency correlation indices are proposed to quantify the similarities among events. MDS has the advantage of avoiding sensitivity to the non-uniform spatial distribution of seismic data, resulting from poorly instrumented areas, and is well suited for accessing dynamics of complex systems. MDS maps are proven as an intuitive and useful visual representation of the complex relationships that are present among seismic events, which may not be perceived on traditional geographic maps. Therefore, MDS constitutes a valid alternative to classic visualization tools, for understanding the global behavior of earthquakes.

Estudo sobre o insight em pessoas com psicose

Para além das variáveis clínicas e sociodemográficas existem concerteza importantes componentes individuais que desempenham um contributo importante no nível de insight apresentado por cada pessoa doente, por exemplo, o nível de inteligência, personalidade, cultura, experiências passadas, memória, etc. A natureza clínica, emocional e/ou intelectual do termo ajuda-nos a compreender a complexidade da dificuldade que existe na sua tradução e, inclusive, na sua compreensão. Daí que as definições atribuídas ao conceito sejam muito distintas e variem consoante a formação teórica do autor/investigador. Pretende-se, a partir dessa identificação/compreensão, promover a qualidade de vida destas pessoas através do desenvolvimento de novas aprendizagens que possibilitem uma cooperação activa. É igualmente fundamental ir ao encontro das capacidade intactas de maneira a possibilitar a aquisição de novos(s) comportamento(s) que tenham um impacte positivo nas queixas, sinais, sintomas, incapacidade e disfuncionalidade apresentados pelo/a utente. Uma vez que a própria conceptualização do termo traduzirá aquilo que se pretende avaliar,será efectuada uma reflexão detalhada acerca dos instrumentos e definições que têm sido mais utilizadas para explorar o insight nas psicoses.Procurei, no meu trabalho de investigação, realçar e promover a importância que cada sujeito, alvo de intervenção, desempenha ao longo do seu processo de recuperação e na prevenção de recaídas. No seguimento dos objectivos acima descritos, para além da revisão teórica efectuada ao fenómeno em termos de conceptualização e estudos desenvolvidos na área de investigação, foi,neste estudo, realizada a contribuição para a validação do instrumento “Assessment of Insight in Psychosis: a re-standartization of a New Scale” de Marková & Berrios (2003).O fenómeno de insight escolhido pela Insight Scale, relata menos as mudanças vividas em relação à doença mental, e mais a actual consciência e articulação de tais mudanças. Tendo como base uma abordagem psicopedagógica, o fenómeno do insight aqui explorado assentou numa perspectiva reabilitativa, actual e multidimensional, que fosse para além das dimensões clínicas tradicionais. Neste sentido é apresentada uma escala original, intitulada “Escala de Avaliação do Insight e Identificação das Necessidades em Pessoas com Psicose”, bem como um modelo de intervenção psicopedagógico breve, assente nos pressupostos descritos ao longo do trabalho.-----------------------------------------ABSTRACT: The importance of insight in people with mental illnesses was first studied in psychiatry, in the first decades of the 20th century, by people as important as Lewis (1934) and Jaspers (1959). However, this field of investigation was left unexplored for many years. Only in the last decade has this phenomenon become the object of numerous scientific investigations, having been given special attention by its investigators. For this reason a significant number of instruments for evalauting insight in psychotic disorders were developed. Since then many papers have been published, which has allowed for a more in depth knowledge on the subject. Therefore, in recent years, the concept of insight has been developed in an attempt to clarify its compexity. A once dichotomic phenomenon, described in terms of presence or absence, became considered multidimensional, which made the identification of different levels of insight and different dimensions possible. Current concepts categorize insight into five dimensions: the awareness of the patient in relation to his/her mental illness, the awareness of the patient in relation to the social consequences of his/her illness, the awareness of the need for treatment, the awareness of the symptoms and the explanation of those symptoms in relation to the illness. The lack of insight in psychiatry, in general terms, and as this phenomenon has been described, the lack of awareness of having a mental illness, represents one of the most common symptoms of schizophrenia and affects a big part of the population that suffer from this illness. It is estimated that bewteen 50 and 80 per cent of patients with schizophrenia do not believe that they are ill, which, consequently has a big impact in the process of adherence to treatment. It is still not possible, however, to identify all the factors that determine the lack of insight in schizophrenics. There are psychological, social and cultural influences that almost certainly play their role in the lack of insight registered in this pathology.Since the impact of scizophrenia is felt in many aspects of the individual’s life, its effective treatment should be directed at various levels, including the improvement of insight. One of the objectives of this study is to explore the relationship between the level of insight in psychosis and the clinical and sociodemographic variables, the psychopathology and its global functioning. As well as the clinical and sociodemographic variables, there are of course important individual components that contribute to the level of insight seen in each patient, for example, their level of inteligence, personality, culture, past experiences, memory, etc. The clinical, emotional and/or intelectual nature of the term helps us understand the difficulty that lies in its interpretation as well as in its comprehension. Therefore, the definitions attributed to the term are very different and vary according to the theoretical training of the investigator. It is intended, from this identification/understanding, to promote the quality of life of these people through the development of new findings that might enable an active cooperation. It is equally fundamental to observe their unimpaired capacities in order to enable the acquisition of new behaviour(s) that have a positive impact on the complaints, signs, symptoms, incapacity and disfunctioning seen in the patient.As the actual comprehension of the term explains what we intend to evaluate, a detailed reflection is made on the instruments and definitions that have been used the most to explore insight in psychosis.In this investigation I tried to underline and promote the importance that each subject, undergoing medical intervention, plays during his/her process of recovery and prevention of relapses. Considering the above mentioned objectives, as well as a theoretical review of the phenomenon in terms of conceptualization and investigative studies developed, this study contributed to the validation of the instrument.The insight phenomenon chosen by the “Insight Scale”, records less changes experienced in relation to the mental illness and more actual awareness and articulation of these changes. Based on a psychopedagogical approach, the insight phenomenon explored here settled on a rehabilitation, current and multidimensional perspective that would go beyond the traditional clinical dimensions. For this reason an original scale entitled “Insight Evaluation Scale and Need Identification in Psychosis Patients” is presented, as well as a psychopedagogical intervention model soon to be used with admitted patients based on the presuppositions described in this study.

Analysis of Forest Fires by means of Pseudo Phase Plane and Multidimensional Scaling Methods

Forest fires dynamics is often characterized by the absence of a characteristic length-scale, long range correlations in space and time, and long memory, which are features also associated with fractional order systems. In this paper a public domain forest fires catalogue, containing information of events for Portugal, covering the period from 1980 up to 2012, is tackled. The events are modelled as time series of Dirac impulses with amplitude proportional to the burnt area. The time series are viewed as the system output and are interpreted as a manifestation of the system dynamics. In the first phase we use the pseudo phase plane (PPP) technique to describe forest fires dynamics. In the second phase we use multidimensional scaling (MDS) visualization tools. The PPP allows the representation of forest fires dynamics in two-dimensional space, by taking time series representative of the phenomena. The MDS approach generates maps where objects that are perceived to be similar to each other are placed on the map forming clusters. The results are analysed in order to extract relationships among the data and to better understand forest fires behaviour.

Analysis of UV spectral bands using multidimensional scaling

This study describes the change of the ultraviolet spectral bands starting from 0.1 to 5.0 nm slit width in the spectral range of 200–400 nm. The analysis of the spectral bands is carried out by using the multidimensional scaling (MDS) approach to reach the latent spectral background. This approach indicates that 0.1 nm slit width gives higher-order noise together with better spectral details. Thus, 5.0 nm slit width possesses the higher peak amplitude and lower-order noise together with poor spectral details. In the above-mentioned conditions, the main problem is to find the relationship between the spectral band properties and the slit width. For this aim, the MDS tool is to used recognize the hidden information of the ultraviolet spectra of sildenafil citrate by using a Shimadzu UV–VIS 2550, which is in the world the best double monochromator instrument. In this study, the proposed mathematical approach gives the rich findings for the efficient use of the spectrophotometer in the qualitative and quantitative studies.

Analysis of Electricity Market Prices Using Multidimensional Scaling

This paper studies the impact of the energy upon electricity markets using Multidimensional Scaling (MDS). Data from major energy and electricity markets is considered. Several maps produced by MDS are presented and discussed revealing that this method is useful for understanding the correlation between them. Furthermore, the results help electricity markets agents hedging against Market Clearing Price (MCP) volatility.

International News Reporting in the Multidimensional Network: The socio-demographics, professional culture and newswork of foreign correspondents working across Sub-Saharan Africa

Tese apresentada para cumprimento dos requisitos necessários à obtenção do grau de Doutor em Media Digitais

To what extent do aspects of sustainability impact established firms' resilience

An organizations´ level of sustainability has so far been primarily been analyzed within the context of economic performance. This study changes that dependent variable to “resilience”, namely a company’s ability to recover from potential lethal shocks or disruptive events. The research questions aims to investigate whether sustainability and resilience are related. This study utilizes the financial crisis from 2007/08 as disruptive event, as it encompassed market phase-out but also survival by established firms. Two Swiss luxury watchmaking companies have been chosen as industry sample and the study’s investigation is based on a comparative case study approach. The latter applies both quantitative data, in the form of the respective annual company reports, and qualitative data, in the form of semi-structured interviews with three stakeholder groups. Findings indicate that the investigated measures of sustainability are related the investigated companies’ level of resilience. These findings contribute to the building of new theory towards resilience as this study outlines specifically which measures have been proven to be of relevance for companies’ resilience. Moreover, the results are of high relevance for companies that are operating in constant evolving markets and struggling adapting to any disruptive environment as it is outlined why and how comparative companies have to be sustainable in order to become more resilient towards future shocks.