Segmentation of a Speech Signal with Application of Fast Wavelet Transformation

The article describes the method of preliminary segmentation of a speech signal with wavelet transformation use, consisting of two stages. At the first stage there is an allocation of sibilants and pauses, at the second – the further segmentation of the rest signal parts.

Thermochemical conversion of Brewers Spent Grain combined with catalytic reforming of pyrolysis vapours

The brewing process is an energy intensive process that uses large quantities of heat and electricity. To produce this energy requires a high, mainly fossil fuel consumption and the cost of this is increasing each year due to rising fuel costs. One of the main by-products from the brewing process is Brewers Spent Grain (BSG), an organic residue with very high moisture content. It is widely available each year and is often given away as cattle feed or disposed of to landfill as waste. Currently these methods of disposal are also costly to the brewing process. The focus of this work was to investigate the energy potential of BSG via pyrolysis, gasification and catalytic steam reforming, in order to produce a tar-free useable fuel gas that can be combusted in a CHP plant to develop heat and electricity. The heat and electricity can either be used on site or exported. The first stage of this work was the drying and pre-treatment of BSG followed by characterisation to determine its basic composition and structure so it can be evaluated for its usefulness as a fuel. A thorough analysis of the characterisation results helps to better understand the thermal behaviour of BSG feedstock so it can be evaluated as a fuel when subjected to thermal conversion processes either by pyrolysis or gasification. The second stage was thermochemical conversion of the feedstock. Gasification of BSG was explored in a fixed bed downdraft gasifier unit. The study investigated whether BSG can be successfully converted by fixed bed downdraft gasification operation and whether it can produce a product gas that can potentially run an engine for heat and power. In addition the pyrolysis of BSG was explored using a novel “Pyroformer” intermediate pyrolysis reactor to investigate the behaviour of BSG under these processing conditions. The physicochemical properties and compositions of the pyrolysis fractions obtained (bio-oil, char and permanent gases) were investigated for their applicability in a combined heat power (CHP) application.

A spatiotemporal Data Envelopment Analysis (S-T DEA) approach:the need to assess evolving units

One of the major challenges in measuring efficiency in terms of resources and outcomes is the assessment of the evolution of units over time. Although Data Envelopment Analysis (DEA) has been applied for time series datasets, DEA models, by construction, form the reference set for inefficient units (lambda values) based on their distance from the efficient frontier, that is, in a spatial manner. However, when dealing with temporal datasets, the proximity in time between units should also be taken into account, since it reflects the structural resemblance among time periods of a unit that evolves. In this paper, we propose a two-stage spatiotemporal DEA approach, which captures both the spatial and temporal dimension through a multi-objective programming model. In the first stage, DEA is solved iteratively extracting for each unit only previous DMUs as peers in its reference set. In the second stage, the lambda values derived from the first stage are fed to a Multiobjective Mixed Integer Linear Programming model, which filters peers in the reference set based on weights assigned to the spatial and temporal dimension. The approach is demonstrated on a real-world example drawn from software development.

An empirical investigation on firm-level performance of cross border mergers and acquisitions

This empirical study investigates the performance of cross border M&A. The first stage is to identify the determinants of making cross border M&A complete. One focus here is to extend the existing empirical evidence in the field of cross border M&A and exploit the likelihood of M&A from a different perspective. Given the determinants of cross border M&A completions, the second stage is to investigate the effects of cross border M&A on post-acquisition firm performance for both targets and acquirers. The thesis exploits a hitherto unused data base, which consists of those firms that are rumoured to be undertaking M&A, and then follow the deal to completion or abandonment. This approach highlights a number of limitations to the previous literature, which relies on statistical methodology to identify potential but non-existent mergers. This thesis changes some conventional understanding for M&A activity. Cross border M&A activity is underpinned by various motives such as synergy, management discipline, and acquisition of complementary resources. Traditionally, it is believed that these motives will boost the international M&A activity and improve firm performance after takeovers. However, this thesis shows that such factors based on these motives as acquirer’s profitability and liquidity and target’s intangible resource actually deter the completion of cross border M&A in the period of 2002-2011. The overall finding suggests that the cross border M&A is the efficiency-seeking activity rather than the resource-seeking activity. Furthermore, compared with firms in takeover rumours, the completion of M&A lowers firm performance. More specifically, the difficulties in transfer of competitive advantages and integration of strategic assets lead to low firm performance in terms of productivity. Besides, firms cannot realise the synergistic effect and managerial disciplinary effect once a cross border M&A is completed, which suggests a low post-acquisition profitability level.

Pairwise comparison matrices and the error-free property of the decision maker

Pairwise comparison is a popular assessment method either for deriving criteria-weights or for evaluating alternatives according to a given criterion. In real-world applications consistency of the comparisons rarely happens: intransitivity can occur. The aim of the paper is to discuss the relationship between the consistency of the decision maker—described with the error-free property—and the consistency of the pairwise comparison matrix (PCM). The concept of error-free matrix is used to demonstrate that consistency of the PCM is not a sufficient condition of the error-free property of the decision maker. Informed and uninformed decision makers are defined. In the first stage of an assessment method a consistent or near-consistent matrix should be achieved: detecting, measuring and improving consistency are part of any procedure with both types of decision makers. In the second stage additional information are needed to reveal the decision maker’s real preferences. Interactive questioning procedures are recommended to reach that goal.

A Kreps-Scheinkman-állítás érvényessége lineáris keresletű vegyes duopóliumok esetén (The Kreps and Scheinkman result remains valid for mixed duopolies with linear demand)

Vegyes oligopóliumoknak nevezzük az olyan piacszerkezeteket, amelyek esetében a magánvállalatok mellett állami vállalatok is tevékenykednek. A vegyes oligopóliumokban az állami vállalatok részben vagy egészében a társadalmi többletet kívánják maximalizálni. Olyan vegyes duopóliumot vizsgálunk, amelyben a vállalatok előbb kiépítik kapacitásaikat, majd meghatározzák termékük kínálati árát. Kreps-Scheinkman [1983] tisztán magánvállalatos duopóliumokra vizsgált ilyen két időszakos modellt, és megállapította, hogy az első időszaki egyensúlyi kapacitások megegyeznek az azonos költségszerkezetű és kínálati viszonyú Cournot-duopólium egyensúlyi kibocsátásaival. Tanulmányunkban Kreps-Scheinkman [1983] eredményét kiterjesztjük a vegyes duopóliumok - lineáris keresleti görbe és konstans egységköltségek melletti - esetére. _____ In mixed oligopolies, private firms compete with a public firm, which at least partially aims to maximize social surplus. The authors investigate mixed duopolies in which the firms first build capacities simultaneously and then set their prices simultaneously as well. For the same two-stage game with purely private firms Kreps and Scheinkman demonstrated in 1983 that the first-stage equilibrium capacities of the two-stage game are identical with the equilibrium outputs of the Cournot duopoly. This paper extends Kreps and Scheinkman's results to mixed duopolies with linear demands and constant unit costs. It is shown that quantity pre-commitment and Bertrand competition also yield to Cournot outcomes when a public firm is involved, not only in the case of private firms.

Three essays on hospital efficiency

This dissertation analyzes hospital efficiency using various econometric techniques. The first essay provides additional and recent evidence to the presence of contract management behavior in the U.S. hospital industry. Unlike previous studies, which focus on either an input-demand equation or the cost function of the firm, this paper estimates the two jointly using a system of nonlinear equations. Moreover, it addresses the longitudinal problem of institutions adopting contract management in different years, by creating a matched control group of non-adopters with the same longitudinal distribution as the group under study. The estimation procedure then finds that labor, and not capital, is the preferred input in U.S. hospitals regardless of managerial contract status. With institutions that adopt contract management benefiting from lower labor inefficiencies than the simulated non-contract adopters. These results suggest that while there is a propensity for expense preference behavior towards the labor input, contract managed firms are able to introduce efficiencies over conventional, owner controlled, firms. Using data for the years 1998 through 2007, the second essay investigates the production technology and cost efficiency faced by Florida hospitals. A stochastic frontier multiproduct cost function is estimated in order to test for economies of scale, economies of scope, and relative cost efficiencies. The results suggest that small-sized hospitals experience economies of scale, while large and medium sized institutions do not. The empirical findings show that Florida hospitals enjoy significant scope economies, regardless of size. Lastly, the evidence suggests that there is a link between hospital size and relative cost efficiency. The results of the study imply that state policy makers should be focused on increasing hospital scale for smaller institutions while facilitating the expansion of multiproduct production for larger hospitals. The third and final essay employs a two staged approach in analyzing the efficiency of hospitals in the state of Florida. In the first stage, the Banker, Charnes, and Cooper model of Data Envelopment Analysis is employed in order to derive overall technical efficiency scores for each non-specialty hospital in the state. Additionally, input slacks are calculated and reported in order to identify the factors of production that each hospital may be over utilizing. In the second stage, we employ a Tobit regression model in order to analyze the effects a number of structural, managerial, and environmental factors may have on a hospital’s efficiency. The results indicated that most non-specialty hospitals in the state are operating away from the efficient production frontier. The results also indicate that the structural make up, managerial choices, and level of competition Florida hospitals face have an impact on their overall technical efficiency.

Developing a Data-Driven Classification of South Florida Plant Communities

A comprehensive, broadly accepted vegetation classification is important for ecosystem management, particularly for planning and monitoring. South Florida vegetation classification systems that are currently in use were largely arrived at subjectively and intuitively with the involvement of experienced botanical observers and ecologists, but with little support in terms of quantitative field data. The need to develop a field data-driven classification of South Florida vegetation that builds on the ecological organization has been recognized by the National Park Service and vegetation practitioners in the region. The present work, funded by the National Park Service Inventory and Monitoring Program - South Florida/Caribbean Network (SFCN), covers the first stage of a larger project whose goal is to apply extant vegetation data to test, and revise as necessary, an existing, widely used classification (Rutchey et al. 2006). The objectives of the first phase of the project were (1) to identify useful existing datasets, (2) to collect these data and compile them into a geodatabase, (3) to conduct an initial classification analysis of marsh sites, and (4) to design a strategy for augmenting existing information from poorly represented landscapes in order to develop a more comprehensive south Florida classification.

Self-tuning algorithm for dsp-based motion control in cnc applications

This thesis describes the development of an adaptive control algorithm for Computerized Numerical Control (CNC) machines implemented in a multi-axis motion control board based on the TMS320C31 DSP chip. The adaptive process involves two stages: Plant Modeling and Inverse Control Application. The first stage builds a non-recursive model of the CNC system (plant) using the Least-Mean-Square (LMS) algorithm. The second stage consists of the definition of a recursive structure (the controller) that implements an inverse model of the plant by using the coefficients of the model in an algorithm called Forward-Time Calculation (FTC). In this way, when the inverse controller is implemented in series with the plant, it will pre-compensate for the modification that the original plant introduces in the input signal. The performance of this solution was verified at three different levels: Software simulation, implementation in a set of isolated motor-encoder pairs and implementation in a real CNC machine. The use of the adaptive inverse controller effectively improved the step response of the system in all three levels. In the simulation, an ideal response was obtained. In the motor-encoder test, the rise time was reduced by as much as 80%, without overshoot, in some cases. Even with the larger mass of the actual CNC machine, decrease of the rise time and elimination of the overshoot were obtained in most cases. These results lead to the conclusion that the adaptive inverse controller is a viable approach to position control in CNC machinery.

Análise numérica de dutos enterrados sujeitos a elevação e recalque localizado

Problems associated to longitudinal interactions in buried pipelines are characterized as three-dimensional and can lead to different soil-pipe issues. Despite the progress achieved in research on buried pipelines, little attention has been given to the three-dimensional nature of the problem throughout the last decades. Most of researches simplify the problem by considering it in plane strain condition. This dissertation aims to present a study on the behavior of buried pipelines under local settlement or elevation, using three-dimensional simulations. Finite element code Plaxis 3D was used for the simulations. Particular aspects of the numerical modeling were evaluated and parametric analyzes were performed, was investigated the effects of soil arching in three-dimensional form. The main variables investigated were as follows: relative density, displacement of the elevation or settlement zone, elevated zone size, height of soil cover and pipe diameter/thickness ratio. The simulations were performed in two stages. The first stage was involved the validation of the numerical analysis using the physical models put forward by Costa (2005). In the second stage, numerical analyzes of a full-scale pipeline subjected to a localized elevation were performed. The obtained results allowed a detailed evaluation of the redistribution of stresses in the soil mass and the deflections along the pipe. It was observed the reduction of stresses in the soil mass and pipe deflections when the height of soil cover was decreased on regions of the pipe subjected to elevation. It was also shown for the analyzed situation that longitudinal thrusts were higher than vi circumferential trusts and exceeded the allowable stresses and deflections. Furthermore, the benefits of minimizing stress with technical as the false trench, compressible cradle and a combination of both applied to the simulated pipeline were verified

Desenvolvimento de novos biolubrificantes hidráulicos derivados dos óleos de maracujá e de moringa in natura e epoxidados

With the increasing environmental awareness, maximizing biodegradability and minimizing ecotoxicity is the main driving force for new technological developments. Thus, can be developed new biodegradable lubricants for use in environmentally sensitive areas. The aim of this study was to obtain new bio-lubricants from passion fruit (Passiflora edulis Sims f. flavicarpa Degener) and moringa (Moringa oleifera Lamarck) epoxidized oils and develop a new additive package using experimental design for their use as a hydraulic fluid. In the first stage of this work was performed the optimization of the epoxidation process of the oils using fractional experimental design 24-1 , varying the temperature, reaction time, ratio of formic acid and hydrogen peroxide. In the second step was investigated the selectivity, thermodynamics and kinetics of the reaction for obtaining the two epoxides at 30, 50 and 70 °C. The result of the experimental design confirmed that the epoxidation of passion fruit oil requires 2 hours of reaction, 50 °C and a ratio H2O2/C=C/HCOOH (1:1:1). For moringa oil were required 2 hours reaction, 50 °C and a ratio of H2O2/C=C/HCOOH (1:1:1.5). The results of the final conversions were equal to 83.09% (± 0.3) for passion fruit oil epoxide and 91.02 (±0,4) for moringa oil epoxide. Following was made the 23 factorial design to evaluate which are the best concentrations of corrosion inhibitor and anti-wear (IC), antioxidant (BHA) and extreme pressure (EP) additives. The bio-lubricants obtained in this step were characterized according to DIN 51524 (Part 2 HLP) and DIN 51517 (Part 3 CLP) standards. The epoxidation process of the oils was able to improve the oxidative stability and reduce the total acid number, when compared to the in natura oils. Moreover, the epoxidized oils best solubilized additives, resulting in increased performance as a lubricant. In terms of physicochemical performance, the best lubricant fluid was the epoxidized moringa oil with additives (EMO-ADI), followed by the epoxidized passion fruit oil with additives (EPF-ADI) and, finally, the passion fruit in natura oil without additives (PFO). Lastly, was made the investigation of the tribological behavior under conditions of boundary lubrication for these lubricants. The tribological performance of the developed lubricants was analyzed on a HFRR equipment (High Frequency Reciprocating Rig) and the coefficient of friction, which occurs during the contact and the formation of the lubricating film, was measured. The wear was evaluated through optical microscopy and scanning electron microscopy (SEM). The results showed that the addition of extreme pressure (EP) and anti-wear and corrosion inhibitor (CI) additives significantly improve the tribological properties of the fluids. In all assays, was formed a lubricating film that is responsible for reducing the coefficient of metal-to-metal wear. It was observed that the addition of EP and IC additives in the in natura vegetable oils of passion fruit and moringa did not favor a significant reduction in wear. The bio-lubricants developed from passion fruit and moringa oils modified via epoxidation presented satisfactory tribological properties and shown to be potential lubricants for replacement of commercial mineral-based fluids.

Caminhos para a avaliação da formação em odontologia: desenvolvimento, validação e aplicação de critérios

The need for universal access to health and the failure of the pedagogical model centered on the transmission of knowledge has led to changes in the training of health professionals. The objective of this study was to provide a new alternative for evaluating dental students through the development, validation and application of evaluation criteria based on the National Curriculum Guidelines (DCN in Brazil). Therefore, the study was conducted in three phases: development and validation of evaluation criteria of Dentistry courses based on the DCN; a pilot study to verify the applicability of the validated criteria and evaluation of the dentistry courses in the Northeast. In the first stage, a logical model was formulated, allowing for the construction of a criteria matrix, validated by a modified Delphi consensus technique. The validated matrix has the following dimensions: Profile of graduates, health care guidance, teaching and service integration, and pedagogical approach. The pilot study was conducted in five dental courses through a documentary study of the pedagogical project course (PPC), and application of validated questionnaires and interviews with course coordinators. The results of the pilot study indicate the possibility of being verified by means of validated criteria and using different methodological proposals, advances and curricular limitations facing the proposed reorientation of training recommended by DCN. The evaluation of Northeast Dentistry courses was carried out by applying a questionnaire validating a matrix of 30 course coordinators, including public and private institutions. The data were submitted to descriptive analysis, and also tested the difference between means and the correlation between the assessment of the coordinators in the dimensions and sub-dimensions with each other, among the general evaluation of courses and between the following variables: administrative category, time since last curriculum updating, participation in reorienting the training of health professionals programs, ENADE and CPC (Preliminary Concepts of the Course) scores in the year 2013. Positive correlation (p <0.01) was found between the means obtained by the perception of the coordinators in most dimensions, and also between them and the overall performance of the course. There were no significant differences between the coordinators’ perception about course performance and the administrative category (public / private). This difference is slightly higher when the average performance is compared with respect to time due to the last curriculum update, getting better performance in courses with the latest updated curriculum, even with there not 11 being this significant difference between dimensions. Better averages of performance were obtained in courses that do not participate in reorientation programs of professional training, with a significant difference (p<0.05) for the overall score and for all dimensions except the dimensions of teaching-service Integration (p = 0.064). There was no significant correlation between the assessment of coordinators in all dimensions, in the overall assessment or ENADE and CPC scores in 2013. The final instrument proposed in this study is a different alternative assessment for health training of both dentists and other professionals, considering that the DCN providing for the training and graduation of professionals is focused on the health needs of the population, integrated with the SUS (the National Brazilian Health System) and based on student-centered learning.

Construção e validação de instrumento de coleta de dados do casal grávido no âmbito da atenção básica

The research aimed to construct and validate a data collection instrument of pregnant couple as part of primary care. It was considered hypothesis that level of agreement from 70% among participants to validate the expert panel. The document has been based on the Theory of Human Needs by Horta and adjusted by Garcia and Cubas. It is a study of methodological type developed in four stages: identification of empirical indicators to pregnant women through an integrative literature review; evaluation of empirical indicators and their relation to human needs by focus group; structuring of the second version of instrument by categorization of indicators and appearance and content validation of the third version of instrument by judges, by use of Delphi technique. The collection of data was the first stage in months from August to October 2014 in the Journal of Midwifery and Women's Health and Scopus, PubMed, Lilacs, CINAHL, Cochrane databases. The remaining steps were carried out from November 2014 to February 2015. For the focus group was counted with participation of six experts through two meetings. As for the judges, it was obtained a population of 63 and final sample of 51 judges divided into 46 basic health units of Municipal City Health Natal/RN, Brazil. The study was approved by the Research Ethics Committee of Universidade Federal do Rio Grande do Norte, under Protocol number 876.200. For data analysis of the first stage it was used descriptive statistics and results are presented in tables and charts. At that stage were identified 162 empirical indicators and, when they were related to human needs, 64 by them were on psycobiological, 97 on psychosocial and one (1) on psychospiritual needs. Regarding the second and third stages, data were treated by process of categorizing and analyzing the Content Validity Index. The indicators obtained a 100% validation index. In appearance and content validation phase of instrument non-validated items were excluded and other items obtained index above 70%. Furthermore, it obtained 99% content validity index in the second version and 95.7% in the third version of the instrument as a whole and, therefore, validated tool. This instrument contains Health Institution, pregnant woman and her partner identification data, information on the human needs of the pregnant and items pertaining to systematize the collection of pregnant couple data during prenatal care. By the conclusion of the study, nurse shall have an instrument to collect the data of pregnant couple in primary care innovative by considering psychobiological, psychosocial and psychospiritual pregnant needs and insert health and sociodemographic data of pregnant partner in the context of pregnancy. Also, the document will serve as a tool for teaching and research in obstetrical nursing.