Exploring distributed computing tools through data mining tasks

Harnessing idle PCs CPU cycles, storage space and other resources of networked computers to collaborative are mainly fixated on for all major grid computing research projects. Most of the university computers labs are occupied with the high puissant desktop PC nowadays. It is plausible to notice that most of the time machines are lying idle or wasting their computing power without utilizing in felicitous ways. However, for intricate quandaries and for analyzing astronomically immense amounts of data, sizably voluminous computational resources are required. For such quandaries, one may run the analysis algorithms in very puissant and expensive computers, which reduces the number of users that can afford such data analysis tasks. Instead of utilizing single expensive machines, distributed computing systems, offers the possibility of utilizing a set of much less expensive machines to do the same task. BOINC and Condor projects have been prosperously utilized for solving authentic scientific research works around the world at a low cost. In this work the main goal is to explore both distributed computing to implement, Condor and BOINC, and utilize their potency to harness the ideal PCs resources for the academic researchers to utilize in their research work. In this thesis, Data mining tasks have been performed in implementation of several machine learning algorithms on the distributed computing environment.

Clinical and laboratory findings of disseminated Mycobacterium avium complex infection (DMAC) in a pair matched case-control study

A pair matched case/control study was conducted from January 1991 to 30 June 1992 in order to define clinical and laboratory findings associated with DMAC infection in AIDS patients. Since DMAC infection is usually associated with advanced immunodeficiency, and therefore also with other opportunistic illnesses, in addition to the number of CD4+ lymphocytes, cases and controls were matched using the following criteria: date of AIDS diagnosis and antiretroviral therapy, number and severity of associated opportunistic infections and, whenever possible, type of Pneumocystis carinii prophylaxis, age and gender, in this order of relevance. Cases (defined as patients presenting at least one positive culture for MAC at a normally sterile site) and controls presented CD4+ lymphocyte counts below 50 cel/mm3. A significantly higher prevalence of general, digestive and respiratory signs, increased LDH levels, low hemoglobin levels and CD4+ cell counts were recorded for cases when compared to controls. Increases in gGT and alkaline phosphatase levels seen in cases were also recorded for controls. In conclusion, the strategy we used for selecting controls allowed us to detect laboratory findings associated to DMAC infection not found in other advanced immunossupressed AIDS patients without DMAC.

Investigating habitat association of breeding birds using public domain satellite imagery and land cover data.

Dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Science in Geospatial Technologies

Constructing and validating a scale of employee satisfaction with HRM practices in the healthcare context

The concept of HRM perceptions is a growing interest in the literature, as one of the antecedents of HRM outcomes. Regardless, not only the cognitive aspect of perception is interesting in this field (what you think) but also the affective perspective is of interest (how you feel about it). In this study we propose a scale for assessing satisfaction with the perceptions of the HRM practices. A 24 item Likert-type scale was developed considering literature review, to assess subjects’ satisfaction with Human Resources Practices in a healthcare setting. Talked reflections were held and a survey encompassing all workers from a Hospital was conducted later, with a sample of 922 subjects. Exploratory and Confirmatory Factor Analysis were performed; reliability was tested using Cronbach’s alpha. The scale presents good psychometric properties with alpha values that range from .71 to .91. Exploratory and Confirmatory Factor Analysis demonstrated that the scale presents a very good fit with CFI= 0.94, AGFI= 0.88, and RMSEA= 0.07. The present study represents a first approach in the usage of this scale and despite having a large sample, respondents originate from a single institution. This study presents a pertinent scale towards measuring a seldom explored construct of the worker-organization relationship. The scale is parsimonious and results are promising. There seems to be very little research on how subjects feel about the HRM practices. This construct, very much in line with more recent studies concerning worker perceptions can be especially interesting in the context of the worker-organization relationship.

Deteção e extinção de incêndio em Data Center

O presente trabalho enquadra-se na temática de segurança contra incêndio em edifícios e consiste num estudo de caso de projeto de deteção e extinção de incêndio num Data Center. Os objetivos deste trabalho resumem-se à realização de um estudo sobre o estado da arte da extinção e deteção automática de incêndio, ao desenvolvimento de uma ferramenta de software de apoio a projetos de extinção por agentes gasosos, como também à realização de um estudo e uma análise da proteção contra incêndios em Data Centers. Por último foi efetuado um estudo de caso. São abordados os conceitos de fogo e de incêndio, em que um estudo teórico à temática foi desenvolvido, descrevendo de que forma pode o fogo ser originado e respetivas consequências. Os regulamentos nacionais relativos à Segurança Contra Incêndios em Edifícios (SCIE) são igualmente abordados, com especial foco nos Sistemas Automáticos de Deteção de Incêndio (SADI) e nos Sistemas Automáticos de Extinção de Incêndio (SAEI), as normas nacionais e internacionais relativas a esta temática também são mencionadas. Pelo facto de serem muito relevantes para o desenvolvimento deste trabalho, os sistemas de deteção de incêndio são exaustivamente abordados, mencionando características de equipamentos de deteção, técnicas mais utilizadas como também quais os aspetos a ter em consideração no dimensionamento de um SADI. Quanto aos meios de extinção de incêndio foram mencionados quais os mais utilizados atualmente, as suas vantagens e a que tipo de fogo se aplicam, com especial destaque para os SAEI com utilização de gases inertes, em que foi descrito como deve ser dimensionado um sistema deste tipo. Foi também efetuada a caracterização dos Data Centers para que seja possível entender quais as suas funcionalidades, a importância da sua existência e os aspetos gerais de uma proteção contra incêndio nestas instalações. Por último, um estudo de caso foi desenvolvido, um SADI foi projetado juntamente com um SAEI que utiliza azoto como gás de extinção. As escolhas e os sistemas escolhidos foram devidamente justificados, tendo em conta os regulamentos e normas em vigor.

Deteção e extinção de incêndios em Data Centers

São muitas as organizações que por todo o mundo possuem instalações deste tipo, em Portugal temos o exemplo da Portugal Telecom que recentemente inaugurou o seu Data Center na Covilhã. O desenvolvimento de um Data Center exige assim um projeto muito cuidado, o qual entre outros aspetos deverá garantir a segurança da informação e das próprias instalações, nomeadamente no que se refere à segurança contra incêndio.

Replication vs erasure coding in data centric storage for wireless sensor networks

In-network storage of data in wireless sensor networks contributes to reduce the communications inside the network and to favor data aggregation. In this paper, we consider the use of n out of m codes and data dispersal in combination to in-network storage. In particular, we provide an abstract model of in-network storage to show how n out of m codes can be used, and we discuss how this can be achieved in five cases of study. We also define a model aimed at evaluating the probability of correct data encoding and decoding, we exploit this model and simulations to show how, in the cases of study, the parameters of the n out of m codes and the network should be configured in order to achieve correct data coding and decoding with high probability.

Mode-Controlled Data-Flow Modeling of Real-Time Memory Controllers

Accepted in 13th IEEE Symposium on Embedded Systems for Real-Time Multimedia (ESTIMedia 2015), Amsterdam, Netherlands.

A microscope for the data center

Nowadays, data centers are large energy consumers and the trend for next years is expected to increase further, considering the growth in the order of cloud services. A large portion of this power consumption is due to the control of physical parameters of the data center (such as temperature and humidity). However, these physical parameters are tightly coupled with computations, and even more so in upcoming data centers, where the location of workloads can vary substantially due, for example, to workloads being moved in the cloud infrastructure hosted in the data center. Therefore, managing the physical and compute infrastructure of a large data center is an embodiment of a Cyber-Physical System (CPS). In this paper, we describe a data collection and distribution architecture that enables gathering physical parameters of a large data center at a very high temporal and spatial resolution of the sensor measurements. We think this is an important characteristic to enable more accurate heat-flow models of the data center and with them, find opportunities to optimize energy consumptions. Having a high-resolution picture of the data center conditions, also enables minimizing local hot-spots, perform more accurate predictive maintenance (failures in all infrastructure equipments can be more promptly detected) and more accurate billing. We detail this architecture and define the structure of the underlying messaging system that is used to collect and distribute the data. Finally, we show the results of a preliminary study of a typical data center radio environment.

Integer and Fractional Order Entropy Analysis of Earthquake Data-series

This paper studies the statistical distributions of worldwide earthquakes from year 1963 up to year 2012. A Cartesian grid, dividing Earth into geographic regions, is considered. Entropy and the Jensen–Shannon divergence are used to analyze and compare real-world data. Hierarchical clustering and multi-dimensional scaling techniques are adopted for data visualization. Entropy-based indices have the advantage of leading to a single parameter expressing the relationships between the seismic data. Classical and generalized (fractional) entropy and Jensen–Shannon divergence are tested. The generalized measures lead to a clear identification of patterns embedded in the data and contribute to better understand earthquake distributions.

Entropy Analysis of Industrial Accident Data Series

Complex industrial plants exhibit multiple interactions among smaller parts and with human operators. Failure in one part can propagate across subsystem boundaries causing a serious disaster. This paper analyzes the industrial accident data series in the perspective of dynamical systems. First, we process real world data and show that the statistics of the number of fatalities reveal features that are well described by power law (PL) distributions. For early years, the data reveal double PL behavior, while, for more recent time periods, a single PL fits better into the experimental data. Second, we analyze the entropy of the data series statistics over time. Third, we use the Kullback–Leibler divergence to compare the empirical data and multidimensional scaling (MDS) techniques for data analysis and visualization. Entropy-based analysis is adopted to assess complexity, having the advantage of yielding a single parameter to express relationships between the data. The classical and the generalized (fractional) entropy and Kullback–Leibler divergence are used. The generalized measures allow a clear identification of patterns embedded in the data.

A framework for using real data with distributed low cost sensors

Currently, due to the widespread use of computers and the internet, students are trading libraries for the World Wide Web and laboratories with simulation programs. In most courses, simulators are made available to students and can be used to proof theoretical results or to test a developing hardware/product. Although this is an interesting solution: low cost, easy and fast way to perform some courses work, it has indeed major disadvantages. As everything is currently being done with/in a computer, the students are loosing the “feel” of the real values of the magnitudes. For instance in engineering studies, and mainly in the first years, students need to learn electronics, algorithmic, mathematics and physics. All of these areas can use numerical analysis software, simulation software or spreadsheets and in the majority of the cases data used is either simulated or random numbers, but real data could be used instead. For example, if a course uses numerical analysis software and needs a dataset, the students can learn to manipulate arrays. Also, when using the spreadsheets to build graphics, instead of using a random table, students could use a real dataset based, for instance, in the room temperature and its variation across the day. In this work we present a framework which uses a simple interface allowing it to be used by different courses where the computers are the teaching/learning process in order to give a more realistic feeling to students by using real data. A framework is proposed based on a set of low cost sensors for different physical magnitudes, e.g. temperature, light, wind speed, which are connected to a central server, that the students have access with an Ethernet protocol or are connected directly to the student computer/laptop. These sensors use the communication ports available such as: serial ports, parallel ports, Ethernet or Universal Serial Bus (USB). Since a central server is used, the students are encouraged to use sensor values results in their different courses and consequently in different types of software such as: numerical analysis tools, spreadsheets or simply inside any programming language when a dataset is needed. In order to do this, small pieces of hardware were developed containing at least one sensor using different types of computer communication. As long as the sensors are attached in a server connected to the internet, these tools can also be shared between different schools. This allows sensors that aren't available in a determined school to be used by getting the values from other places that are sharing them. Another remark is that students in the more advanced years and (theoretically) more know how, can use the courses that have some affinities with electronic development to build new sensor pieces and expand the framework further. The final solution provided is very interesting, low cost, simple to develop, allowing flexibility of resources by using the same materials in several courses bringing real world data into the students computer works.

A module for Data Centric Storage in ns-3

Demo in Workshop on ns-3 (WNS3 2015). 13 to 14, May, 2015. Castelldefels, Spain.

Using data mining with time series data in short-term stocks prediction

Data Mining (DM) methods are being increasingly used in prediction with time series data, in addition to traditional statistical approaches. This paper presents a literature review of the use of DM with time series data, focusing on short- time stocks prediction. This is an area that has been attracting a great deal of attention from researchers in the field. The main contribution of this paper is to provide an outline of the use of DM with time series data, using mainly examples related with short-term stocks prediction. This is important to a better understanding of the field. Some of the main trends and open issues will also be introduced.

Uma perspectiva foucaudiana na auditoria à avaliação de desempenho na administração pública

Motivation: Auditing is not merely a collection of technical tasks but also a programmatic idea circulating in organizational environment, an idea which promises a certain style of control and organizational transparency (Power, 1998, p. 122) Performance appraisal within public organization aims to promote this organizational transparency and promote learning and improvement process both for employees and for the organization. However, we suggest that behind its clear intentions, there are some other goals tied to performance appraisal that could be seen as components of a discipline and surveillance systems to make the employee “knowable, calculable and administrative object” (Miller and Rose, 1990, p. 5). Objective: In Portuguese public organizations, performance appraisal follows the SIADAP (Performance Appraisal Systems for Public Administration). The objective of this study is to capture whatever employees of public organizations (appraisers and appraisee) perceived the performance appraisal system (SIADAP) as an appraisal model that promotes equity, learning and improvement or just as an instrument of control to which they feel dominated and watched over. Method: We developed an in-depth qualitative case study using semi-structured interviews with appraisers and their subordinates in the administrative department of a university institute of Medicine. The discourse of the participants was theoretically analyzed based on Foucauldian framework. Prior to qualitative data collection, we collected quantitative data, with a questionnaire, to measure the (un)satisfaction of employees with the all appraisal system. Findings: Although some key points of Foucault perspective were identified, its framework revealed some limitations to capture the all complexity of performance appraisal. Qualitative data revealed a significant tendency in discourses of appraisers and their subordinates considering SIADAP as an instrument that’s aims to introduced political rationalities and limits to the employer’s promotions within their careers. Contribution: This study brings a critical perspectives and new insights about performance appraisals in Portuguese’s public administrations. It is original contribution to management of human recourses in public administration and primary to audit of performance appraisal systems.