Comparação do controle do inversor trifásico conectado à rede com filtro LCL considerando o amortecimento passivo e ativo

Distributed generation systems must fulfill standards specifications of current harmonics injected to the grid. In order to satisfy these grid requirements, passive filters are connected between inverter and grid. This work compares the characteristic response of the traditional inductive (L) filter with the inductive-capacitive-inductive (LCL) filter. It is shown that increasing the inductance L leads to a good ripple current suppression around the inverter switching frequency. The LCL filter provides better harmonic attenuation and reduces the filter size. The main drawback is the LCL filter impedance, which is characterized by a typical resonance peak, which must be damped to avoid instability. Passive or active techniques can be used to damp the LCL resonance. To address this issue, this dissertation presents a comparison of current control for PV grid-tied inverters with L filter and LCL filter and also discuss the use of active and passive damping for different regions of resonance frequency. From the mathematical models, a design methodology of the controllers was developed and the dynamic behavior of the system operating in closed loop was investigated. To validate the studies developed during this work, experimental results are presented using a three-phase 5kW experimental platform. The main components and their functions are discussed in this work. Experimental results are given to support the theoretical analysis and to illustrate the performance of grid-connected PV inverter system. It is shown that the resonant frequency of the system, and sampling frequency can be associated in order to calculate a critical frequency, below which is essential to perform the damping of the LCL filter. Also, the experimental results show that the active buffer per virtual resistor, although with a simple development, is effective to damp the resonance of the LCL filter and allow the system to operate stable within predetermined parameters.

Avaliação de um sistema de resfriamento passivo para o clima de Curitiba

Direct evaporative cooling systems (DECS) based on sprinkling water indoors in the form of droplets and indirect evaporative cooling systems (IECS), characterized by the use of wetted roof or wall surfaces for cooling without increasing the indoor air moisture, consist of interesting bioclimatic strategies still not quite explored in Brazil. This study aims to evaluate the use of a particular form of IECS (which combines evaporative cooling and thermal mass brought about by a water reservoir) for indoor thermal control in warm conditions in Curitiba, Two test cells were initially built, monitored and compared to each other: a control module (CM) and an experimental module (EM), the latter provided with an evaporative pond. A subsequent configuration of the system which cancels out the evaporative function of the system and that is solely based on the increase of thermal mass, was tested in a second monitoring round. A third configuration of EM combinig evaporative cooling and the increase of termal mass was tested. Results showed a higher effectiveness of the IECS for the indoor cooling of the tested cells. The average temperature in EM was reduced in 2.5°C and the maximum temperature was reduced in 8.0°C in comparison with the CM. Results also showed a strong relation between the wet-bulb temperature depression and the internal temperature decrease achieved by the evaporative cooling strategy.

Proyecto de diseño y cálculo de retroexcavadora de pala frontal

El objetivo del presente proyecto es el diseño y cálculo de la pala frontal para una retroexcavadora de minería. Para el desarrollo del proyecto se han realizado una serie de estudios con sus respectivas iteraciones hasta lograr un equilibrio entre todos los elementos a estudio. Partiendo de la función objetivo a cumplir por el diseño, el primer paso consiste en definir el tipo de mecanismo más adecuado a las necesidades planteadas mediante un proceso de síntesis estructural. De esta forma se obtiene el tipo y número de elementos y pares a utilizar, así como su secuencia de unión (diagrama estructural). A continuación, a partir de las especificaciones dimensionales dadas por la empresa minera se obtienen las dimensiones principales del mecanismo, es decir, las longitudes, las posiciones y orientaciones relativas entre pares. Una vez obtenidas las dimensiones principales, se aplica cinemática inversa, para obtener la trayectoria de las posiciones a estudio y a continuación se realiza el análisis cinemático para los valores calculados para dichas posiciones. Por tanto, es necesario hacer una estimación inicial de las secciones de los elementos, pudiendo tomar como referencia aquellas que en otros diseños similares hayan resultado adecuadas. Con la distribución másica que implican estas dimensiones secundarias, y suministrando como dato el movimiento requerido para el mecanismo, así como todas las acciones resistentes a las que está sometido, se resuelve el problema dinámico. Este da como resultado las reacciones en los pares y las acciones motoras necesarias para que el sistema se mueva como previamente se ha especificado. Si los esfuerzos en los elementos generan un fallo (estático) en cualquiera de los elementos de la máquina, se modifican los materiales y dimensiones de las secciones en cuestión, y se realiza de nuevo un análisis cinetostático hasta que las dimensiones secundarias de los elementos sean tales que resistan las reacciones que aparecerán. A partir de aquí, si la diferencia entre lo requerido y los resultados obtenidos son aceptables, puede darse como válido el diseño. En caso contrario habría que modificar las características inerciales de los elementos y proseguir con el ciclo del diseño.

Sujeito passivo misto de IVA

O presente estudo procura dar a conhecer algumas das problemáticas relacionadas com a sujeição ao IVA e a qualidade de sujeito passivo misto, em particular as autarquias locais.

Análise de métodos de predição de conforto térmico de habitação em clima quente-úmido com condicionamento passivo

The assessment of building thermal performance is often carried out using HVAC energy consumption data, when available, or thermal comfort variables measurements, for free-running buildings. Both types of data can be determined by monitoring or computer simulation. The assessment based on thermal comfort variables is the most complex because it depends on the determination of the thermal comfort zone. For these reasons, this master thesis explores methods of building thermal performance assessment using variables of thermal comfort simulated by DesignBuilder software. The main objective is to contribute to the development of methods to support architectural decisions during the design process, and energy and sustainable rating systems. The research method consists on selecting thermal comfort methods, modeling them in electronic sheets with output charts developed to optimize the analyses, which are used to assess the simulation results of low cost house configurations. The house models consist in a base case, which are already built, and changes in thermal transmittance, absorptance, and shading. The simulation results are assessed using each thermal comfort method, to identify the sensitivity of them. The final results show the limitations of the methods, the importance of a method that considers thermal radiance and wind speed, and the contribution of the chart proposed

O novo Código florestal e a regularização do passivo ambiental dos imóveis rurais : o caso de Querência

Dissertação (mestrado)—Universidade de Brasília, Centro de Desenvolvimento Sustentável, Programa de Pós-Graduação em Desenvolvimento Sustentável, 2016.

Passivo ambiental: estudo de caso

Dissertação apresentada para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Contabilidade e Finanças

Design gráfico da pluma de contaminação por compostos orgânicos voláteiss utilizando software CAD na investigação de passivo ambiental em um posto revendedor de combustíveis em Natal/RN

Among the potentially polluting economic activities that compromise the quality of groundwater are the gas stations. The city of Natal has about 120 gas stations, of which only has an environmental license for operation. Discontinuities in the offices were notified by the Public Ministry of Rio Grande do Norte to carry out the environmental adaptations, among which is the investigation of environmental liabilities. The preliminary and confirmatory stages of this investigation consisted in the evaluation of soil gas surveys with two confirmatory chemical analysis of BTEX, PAH and TPH. To get a good evaluation and interpretation of results obtained in the field, it became necessary three-dimensional representation of them. We used a CAD software to graph the equipment installed in a retail service station fuel in Natal, as well as the plumes of contamination by volatile organic compounds. The tool was concluded that contamination is not located in the current system of underground storage of fuel development, but reflects the historical past in which tanks were removed not tight gasoline and diesel

Diagnóstico do passivo ambiental no projeto de assentamento Luis Lopes Sobrinho, São Francisco do Pará-PA.

A região nordeste do Estado do Pará constitui uma das mais antigas áreas de ocupação na região amazônica que, por conseguinte, necessita de estudos para mitigar os seus impactos ambientais. Neste trabalho é avaliada espacialmente a situação das áreas com restrições legais ao uso do solo (Áreas de Preservação Permanente e Áreas de Reserva Legal) no Projeto de Assentamento Luis Lopes Sobrinho, a partir de ferramentas de geotecnologias. Foi verificado que apesar da maior parte das APPs estarem preservadas, existe uma parcela a ser recuperada de 22,23 ha (13,58% do total). No que tange a ARL, o total de área de tipologia florestal necessária à averbação possui um deficit de 221,33 ha (10,14% do total). Ainda que a área de APP preservada fosse contabilizada para a averbação da ARL, não seria possível atingir os 50% do total da propriedade (2.182,60 ha) previstos em lei.

Disabled Revolutionary War Veterans and the Construction of Disability in the Early United States, c. 1776-1840

This thesis addresses the following broad research question: what did it mean to be a disabled Revolutionary War veteran in the early United States during the period from 1776 to roughly 1840? The study approaches the question from two angles: a state-centred one and an experiential one. In both cases, the theoretical framework employed comes from disability studies. Consequently, disability is regarded as a sociocultural phenomenon rather than a medical condition. The state-centred dimension of the study explores the meaning of disability and disabled veterans to the early American state through an examination of the major military pension laws of the period. An analysis of this legislation, particularly the invalid pension acts of 1793 and 1806, indicates that the early United States represents a key period in the development of the modern disability category. The experiential approach, in contrast, shifts the focus of attention away from the state towards the lived experiences of disabled veterans. It seeks to address the issue of whether or not the disabilities of disabled veterans had any significant material impact on their everyday lives. It does this through a comparison of the situation of 153 disabled veterans with that of an equivalent number of nondisabled veterans. The former group received invalid pensions while the latter did not. In comparing the material conditions of disabled and nondisabled veterans, a wide range of primary sources from military records to memoirs and letters are used. The most important sources in this regard are the pension application papers submitted by veterans in the early nineteenth century. These provide us with a unique insight into the everyday lives of veterans. Looking at the issue of experience through the window of the pension files reveals that there was not much difference in the broad contours of disabled and nondisabled veteran life. This finding has implications for the theorisation of disability that are highlighted and discussed in the thesis. The main themes covered in this study are: the wartime experiences of injured American soldiers, the military pension establishment of the early United States and the legal construction of disability, and the post-war working and family lives of disabled veterans. Keywords: disability, early America, veterans, military pensions, disabled people, Revolutionary War, United States, disability theory.

Assessing the sustainability of wheat-based cropping systems using APSIM: Model parameterisation and evaluation

Assessing the sustainability of crop and soil management practices in wheat-based rotations requires a well-tested model with the demonstrated ability to sensibly predict crop productivity and changes in the soil resource. The Agricultural Production Systems Simulator (APSIM) suite of models was parameterised and subsequently used to predict biomass production, yield, crop water and nitrogen (N) use, as well as long-term soil water and organic matter dynamics in wheat/chickpea systems at Tel Hadya, north-western Syria. The model satisfactorily simulated the productivity and water and N use of wheat and chickpea crops grown under different N and/or water supply levels in the 1998-99 and 1999-2000 experimental seasons. Analysis of soil-water dynamics showed that the 2-stage soil evaporation model in APSIM's cascading water-balance module did not sufficiently explain the actual soil drying following crop harvest under conditions where unused water remained in the soil profile. This might have been related to evaporation from soil cracks in the montmorillonitic clay soil, a process not explicitly simulated by APSIM. Soil-water dynamics in wheat-fallow and wheat-chickpea rotations (1987-98) were nevertheless well simulated when the soil water content in 0-0.45 m soil depth was set to 'air dry' at the end of the growing season each year. The model satisfactorily simulated the amounts of NO3-N in the soil, whereas it underestimated the amounts of NH 4-N. Ammonium fixation might be part of the soil mineral-N dynamics at the study site because montmorillonite is the major clay mineral. This process is not simulated by APSIM's nitrogen module. APSIM was capable of predicting long-term trends (1985-98) in soil organic matter in wheat-fallow and wheat-chickpea rotations at Tel Hadya as reported in literature. Overall, results showed that the model is generic and mature enough to be extended to this set of environmental conditions and can therefore be applied to assess the sustainability of wheat-chickpea rotations at Tel Hadya.

Assessing the sustainability of wheat-based cropping systems using simulation modelling: sustainability

Concepts of agricultural sustainability and possible roles of simulation modelling for characterising sustainability were explored by conducting, and reflecting on, a sustainability assessment of rain-fed wheat-based systems in the Middle East and North Africa region. We designed a goal-oriented, model-based framework using the cropping systems model Agricultural Production Systems sIMulator (APSIM). For the assessment, valid (rather than true or false) sustainability goals and indicators were identified for the target system. System-specific vagueness was depicted in sustainability polygons-a system property derived from highly quantitative data-and denoted using descriptive quantifiers. Diagnostic evaluations of alternative tillage practices demonstrated the utility of the framework to quantify key bio-physical and chemical constraints to sustainability. Here, we argue that sustainability is a vague, emergent system property of often wicked complexity that arises out of more fundamental elements and processes. A 'wicked concept of sustainability' acknowledges the breadth of the human experience of sustainability, which cannot be internalised in a model. To achieve socially desirable sustainability goals, our model-based approach can inform reflective evaluation processes that connect with the needs and values of agricultural decision-makers. Hence, it can help to frame meaningful discussions, from which actions might emerge.

Psykoottisen mielenterveyspotilaan uskonnonvapaus

Tämän tutkimuksen tarkoituksena on selvittää psykoottisen mielenterveyspotilaan uskonnonvapautta. Tutkimuskysymyksiä on kolme: Millä perusteilla psykoottisen potilaan uskonnonvapaus on turvattu ja millä perusteilla sitä rajoitetaan? Miten psykoottinen ja uskonnollinen todellisuudentulkinta eroavat toisistaan? Vaarantaako psykiatriseen todellisuudentulkintaan perustuva hoito potilaan negatiivisen uskonnonvapauden eli oikeuden elää ilman uskontoa? Tutkimusmetodina on systemaattinen analyysi. Lähteet ovat perustusoikeudet, mielenterveyslaki, potilaslaki, YK:n Principles for the protection of persons with mental illness and the improvement of mental health care, Maailman psykiatriyhdistyksen Madridin julistus ja Suomen mielenterveysseuran Mielenterveyspotilaan oikeudet. Uskonnonvapautta tarkastellaan tässä tutkimuksessa kahden eri vapauskäsityksen näkökulmasta: ulkoisena vapautena, joka edellyttää kompetenssia ja autenttisuutta, sekä ulkoisen ja sisäisen vapauden summana, johon kompetenssi ja autenttisuus sisältyvät. Psykoottisella potilaalla on ihmisyytensä ja kansalaisuutensa perusteella lähtökohtaisesti täysi uskonnonvapaus, mutta sitä voidaan rajoittaa. Jos uskonnonvapaus ymmärretään ulkoiseksi vapaudeksi, rajoittaa psykoottisen potilaan uskonnonvapautta tahdosta riippumattomassa hoidossa hänen terveytensä ja turvallisuutensa suojaaminen. Uskonnonvapauden rajoittaminen voidaan perustella sillä, ettei psykoottinen potilas täytä uskonnonvapauden edellytyksiä eli kompetenssia ja autenttisuutta, sillä, että potilaan terveyteen ja turvallisuuteen liittyvät oikeudet priorisoidaan uskonnonvapauden yläpuolelle sekä sillä, että pyritään terveyshyötyyn. Jos uskonnonvapaus ymmärretään ulkoisen ja sisäisen vapauden summaksi, on psykoosi uskonnonvapautta rajoittava tekijä, koska se tekee yksilöstä epäautenttisen ja puuttuu hänen kompetenssiinsa. Psykoosin (myös tahdosta riippumaton) hoito voidaan ymmärtää tällöin yritykseksi palauttaa uskonnonvapaus. Rajoittamalla ulkoista uskonnonvapautta pyritään maksimoimaan ulkoisen ja sisäisen uskonnonvapauden summa. Vaikka psykoottisella ja uskonnollisella todellisuudentulkinnalla on yhtäläisyyksiä, niiden toisistaan erottaminen on tärkeää, koska yksilöllä, jonka todellisuudentulkinta määritellään psykoottiseksi, on oikeus saada hoitoa, kun taas yksilön uskonnollista todellisuudentulkintaa suojaa uskonnonvapaus eikä sitä saa hoitaa sairautena. Lähteiden mukaan psykoottisen ja uskonnollisen todellisuudentulkinnan toisistaan erottaminen diagnostisten kriteerien ja lääketieteellisen tiedon avulla on lääkärin tehtävä. Tutkimuksessani esitän kaksi periaatetta, joiden avulla todellisuudentulkinnat voidaan erottaa toisistaan. Yksinäinen puu ei pala -periaatteen mukaan yksilön todellisuudentulkinta on uskonnollinen, mikäli se jaetaan jossain yhteisössä. Hedelmistään puu tunnetaan -periaatteen mukaan yksilön todellisuudentulkinta on uskonnollinen, mikäli sen terveydelliset ja sosiaaliset seuraukset ovat hyvät. Antipsykiatrinen kritiikki väittää psykiatrian olevan uskonto. Jos väite on tosi, puututaan tahdosta riippumattomassa hoidossa yksilön oikeuteen elää ilman uskontoa, sillä ko. hoidossa olevan psykoottisen potilaan on pakko suostua siihen, että häntä hoidetaan psykiatrian arvojen ja todellisuudentulkinnan mukaan. Vaikuttaa kuitenkin siltä, että jos psykiatria määritellään uskonnoksi, uskonnon käsite kärsii inflaation. Koska psykoottisen potilaan uskonnonvapaus on pohjimmiltaan eettinen kysymys, on tärkeää myöntää psykiatrian arvosidonnaisuus. Tällöin voidaan tehdä tietoisesti moraalisia päätöksiä ja kantaa moraalinen vastuu esimerkiksi diagnoosin määrittelyssä. Psykiatrian voidaan katsoa perustuvan universaaleihin arvoihin samalla tavalla kuin ihmisoikeuksienkin.

Preterm Birth and Surgical Treatment of the Uterine Cervix

Cervical cancer is the second most common cancer among women globally. Most, probably all cases, arise through a precursor, cervical intraepithelial neoplasia (CIN). Effective cytological screening programmes and surgical treatments of precancerous lesions have dramatically reduced its prevalence and related mortality. Although these treatments are effective, they may have adverse effects on future fertility and pregnancy outcomes. The aim of this study was to evaluate the effects of surgical treatment of the uterine cervix on pregnancy and fertility outcomes, with the focus particularly on preterm birth. The general preterm birth rates and risk factors during 1987–2005 were studied. Long-term mortality rates of the treated women were studied. In this study, information from The Medical Birth Register (MBR), The Hospital Discharge Register (HDR), The Cause-of-Death Register (CDR), and hospital records were used. Treatments were performed during 1987–2003 and subsequent deliveries, IVF treatments and deaths were analyzed. The general preterm birth rate in Finland was relatively stable, varying from 5.1% to 5.4% during the study period (1987 to 2005), although the proportion of extremely preterm births had decreased substantially by 12%.The main risk factor as regards preterm birth was multiplicity, followed by elective delivery (induction of delivery or elective cesarean section), primiparity, in vitro fertilization treatment, maternal smoking and advanced maternal age. The risk of preterm birth and low birth weight was increased after any cervical surgical treatment; after conization the risk of preterm birth was almost two-fold (RR 1.99, 95% CI 1.81– 2.20). In the conization group the risk was the highest for very preterm birth (28–31 gestational weeks) and it was also high for extremely preterm birth (less than 28 weeks). In this group the perinatal mortality was also increased. In subgroup analysis, laser ablation was not associated with preterm birth. When comparing deliveries before and after Loop conization, we found that the risk of preterm birth was increased 1.94-fold (95% CI 1.10–3.40). Adjusting for age, parity, or both did not affect our results. Large or repeat cones increased the risk of preterm birth when compared with smaller cones, suggesting that the size of the removed cone plays a role. This was corroborated by the finding that repeat treatment increased the risk as much as five-fold when compared with the background preterm birth rate. We found that the proportion of IVF deliveries (1.6% vs. 1.5%) was not increased after treatment for CIN when adjusted for year of delivery, maternal age, or parity. Those women who received both treatment for CIN and IVF treatment were older and more often primiparous, which explained the increased risk of preterm birth. We also found that mortality rates were 17% higher among women previously treated for CIN. This excess mortality was particularly seen as regards increased general disease mortality and alcohol poisoning (by 13%), suicide (by 67%) and injury death (by 31%). The risk of cervical cancer was high, as expected (SMR 7.69, 95% CI 4.23–11.15). Women treated for CIN and having a subsequent delivery had decreased general mortality rate (by -22%), and decreased disease mortality (by -37%). However, those with preterm birth had increased general mortality (SMR 2.51, 95% CI 1.24–3.78), as a result of cardiovascular diseases, alcohol-related causes, and injuries. In conclusion, the general preterm birth rate has not increased in Finland, as in many other developed countries. The rate of extremely preterm births has even decreased. While other risk factors of preterm birth, such as multiplicity and smoking during pregnancy have decreased, surgical treatments of the uterine cervix have become more important risk factors as regards preterm birth. Cervical conization is a predisposing factor as regards preterm birth, low birth weight and even perinatal mortality. The most frequently used treatment modality, Loop conization, is also associated with the increased risk of preterm birth. Treatments should be tailored individually; low-grade lesions should not be treated at all among young women. The first treatment should be curative, because repeat treatments are especially harmful. The proportion of IVF deliveries was not increased after treatment for CIN, suggesting that current treatment modalities do not strongly impair fertility. The long-term risk of cervical cancer remains high even after many years post-treatment; therefore careful surveillance is necessary. In addition, accidental deaths and deaths from injury were common among treated women, suggesting risk-taking behavior of these women. Preterm birth seems be associated with extremely high mortality rates, due to cardiovascular, alcohol-related and injury deaths. These women could benefit from health counseling, for example encouragement in quitting smoking.

Dynamics of charge transfer in the excited amine complexes of the fullerenes C60 and C70.: A picosecond laser flash photolysis study

In benzene solution, C60 and C70 interact weakly in the ground state with amines having favourable oxidation potentials. Picosecond time-resolved absorption measurements show that on photoexcilation, the weak complexes undergo charge separation to produce ion pairs which in turn undergo fast geminate recombination either to produce the triplet state of the fullerenes or give back the ground slate of the complex, depending on the oxidation potential of the amine. Free-ion yield is generally negligible.