Electric-drive-based control and electric energy regeneration in a hydraulic system

Over the recent years, development in mobile working machines has concentrated on reducing emissions owing to the tightening rules and needs to improve energy utilization and reduce power losses. This study focuses on energy utilization and regeneration in an electro-hydraulic forklift, which is a lifting equipment application. The study starts from the modelling and simulation of a hydraulic forklift. The energy regeneration from the potential energy of the load was studied. Also a flow-based electric motor speed control was suggested in this thesis instead of the throttle control method or the variable displacement pump control. Topics related to further development in the future are discussed. Finally, a summary and conclusions are presented.

Taajuusmuuttajan hyödyntämismahdollisuudet kompressorijärjestelmien elinkaarikustannusten optimoimisessa

Paineilmaa on kutsuttu neljänneksi perushyödykkeeksi veden, sähkön ja kaasun lisäksi. Paineilman kuluttaja on usein myös sen tuottaja. EU:n alueen teollisuudessa keskimää-rin 16 % kulutetusta kokonaissähkötehosta kuluu ilmakompressoreiden käyttöön. Taa-juusmuuttajan käyttö on viime vuosikymmeninä lisääntynyt merkittävästi, kun on pyrit-ty energiatehokkaisiin ratkaisuihin esimerkiksi pumppaus- ja puhallinjärjestelmissä. Kompressorijärjestelmissä taajuusmuuttajien käyttö ei ole vielä yhtä yleistä kuin esi-merkiksi pumppukäytöissä, vaikka taajuusmuuttajan käytöllä saavutetaan useimmissa tapauksissa huomattavia etuja. Tässä työssä tutkitaan taajuusmuuttajan hyödyntämismahdollisuuksia kompressorijär-jestelmien käytönaikaisten elinkaarikustannusten optimoimisessa. Työssä selvitetään säästöpotentiaalia, ja pohditaan pyörimisnopeussäädöllä saavutettavia etuja eri komp-ressorityypeillä. Lopuksi muodostetaan elinkaarikustannusanalyysit kahdelle todelliselle teollisuuden kompressorikohteelle. Tutkimusmenetelminä ovat kirjallisuustyö sekä asi-antuntijahaastattelut teollisuudesta. Työn tavoitteena on kartoittaa taajuusmuuttajan hyödyntämispotentiaalia kompressorijärjestelmissä ja luoda pohjaa mahdolliselle jatko-tutkimukselle.

Evaluation of energy efficiency and best available techniques in pumping processes

The potential for enhancing the energy efficiency of industrial pumping processes is estimated to be in some cases up to 50 %. One way to define further this potential is to implement techniques in accordance to definition of best available techniques in pumping applications. These techniques are divided into three main categories: Design, control method & maintenance and distribution system. In the theory part of this thesis first the definition of best available techniques (BAT) and its applicability on pumping processes is issued. Next, the theory around pumping with different pump types is handled, the main stress being in centrifugal pumps. Other components needed in a pumping process are dealt by presenting different control methods, use of an electric motor, variable speed drive and the distribution system. Last part of the theory is about industrial pumping processes from water distribution, sewage water and power plant applications, some of which are used further on in the empirical part as example cases. For the empirical part of this study four case studies on typical pumping processes from older Master’s these were selected. Firstly the original results were analyzed by studying the distribution of energy consumption between different system components and using the definition of BAT in pumping, possible ways to improve energy efficiency were evaluated. The goal in this study was that by the achieved results it would be possible to identify the characteristic energy consumption of these and similar pumping processes. Through this data it would then be easier to focus energy efficiency actions where they might be the most applicable, both technically and economically.

Energiantuotantovaihtoehtojen vertailu, Jousenpuiston uusi asuinalue

Tämän diplomityön tavoitteena oli vertailla paikallisia energiantuotantovaihtoehtoja eri-tyisesti lämmöntuotantoon painottuen. Tarkastelu sovitettiin uuden matalaenergiarakentamista vastaavan kerrostaloasuinalueen tarpeisiin. Näkökulmana olivat sekä taloudellisuus että hiilidioksidipäästöt. Yksityiskohtaisemman tarkastelun kohteena olivat maalämpö, alueellinen biolämpölaitos sekö alueellinen pien-CHP-laitos. Perusvaihtoehtona tutkittiin kaukolämpöä. Kaikkiin vaihtoehtoihin kuului myös kapasiteetiltaan rajoitettu jäähdytys. Tulosten mukaan kokonaistaloudellisin vaihtoehto oli maalämpö yhdistettynä kaukolämpöön. Tässä vaihtoehdossa peruslämpö tuotetaan maalämmöllä, mutta huippu-lämpöön sekä käyttöveden lämmitykseen käytetään kaukolämpöä. Ratkaisulla saadaan aikaan myös päästövähennyksiä kaukolämpöön verrattuna. Tulosten mukaan pienimmät päästöt olivat pien-CHP-biovoimalaitoksella. Toisaalta nykyisillä sähkön myyntihinnoilla pienimuotoinen yhdistetty sähkön ja lämmön tuotanto ei pysty kilpailemaan kustannusrakenteensa puolesta muiden tutkittujen vaihtoehtojen kanssa.

Lämpöpumppujärjestelmät integroidussa kylmä- ja lämpötehon tuotossa

Tässä työssä tutkittiin lämpöpumppujärjestelmiä, joilla tuotetaan samaan aikaan kylmä- ja lämpötehoa. Höyryn puristus lämpöpumppu on yleisimmin käytetty lämpöpumpputyyppi ja sen pääkomponentit ovat kompressori, lauhdutin, paisuntaventtiili ja höyrystin. Lämpöpumppu tuottaa samaan aikaan kylmätehoa höyrystimellä ja lämpötehoa lauhduttimella. Lämpöpumpun toiminta-arvoihin vaikuttaa valittujen lämpötilatasojen lisäksi voimakkaasti valitun kiertoaineen termodynaamiset ominaisuudet sekä kompressorin painesuhteeseen verrannollinen isentrooppihyötysuhde. Uusissa lämpöpumpuissa käytetään HFC yhdisteitä sekä sekoituksia kiertoaineina, mutta myös luonnolliset aineet, kuten ammoniakki, ovat lupaavia korvikkeita CFC yhdisteille. Sopivia sovelluskohteita kylmä- ja lämpötehon yhteistuotannolle ovat kauppa- ja asuinrakennukset, hotellit, toimistot, elintarviketeollisuus ja -myymälät sekä vierekkäiset jää- ja uimahallit ja hiihtoputket. Kylmä- ja lämpötehon yhteistuotannolla voitaisiin saavuttaa merkittäviä säästöjä ja päästövähennyksiä. Esimerkiksi jäähallien kylmäkoneiden lauhdelämmön hyödyntämisessä olisi Suomessa potentiaalia 6-10 miljoonan euron vuotuisiin säästöihin. Kylmä- ja lämpötehon yhteistuotanto voidaan toteuttaa hyödyntämällä kylmäkoneen lauhdelämpöä toisella lämpöpumpulla. Toinen vaihtoehto on käyttää eri tilojen samanaikaiseen lämmittämiseen ja jäähdyttämiseen HPS lämpöpumppua tai moniyksikköistä lämpöpumppua.

Electrical Equivalent Circuit for Dry Bacteriorhodopsin Sensor

Bacteriorhodopsin (BR) is a photosensitive protein which functions as a light-driven proton pump. Due to its photoactivity, BR could be used in photosensing and information processing which has inspired researchers to study the photoelectric response and the appropriate measurement instrumentation for BR. In this thesis, the measurement instrumentation connected to a dry BR sensor was confirmed to affect the photovoltage response measured by using voltage amplifiers. Changing of the input impedance of the measurement instrumentation was shown to alter a part of the measured photovoltage response. The photocurrent measurements using transimpedance amplifier and the presented electrical equivalent circuit were used to show that the photocurrent measurements have no significant effect on the photoelectric response. The photocurrent was shown to be a derivate of the photovoltage response measured from the dry BR sensor when it was compared to the response measured with a voltage amplifier. This confirmed that another part of the photovoltage response was not affected by the measurement instrumentation. The time-variant behavior of the dry BR sensor was confirmed in both the photocurrent and the photovoltage measurements. This was caused by the fact that the capacitance of the dry BR sensor changes with the excitation light intensity.

Desenvolvimento e produtividade da cultura da batata irrigada por gotejamento em dois sistemas de cultivo

O presente trabalho avalia o desenvolvimento e a produtividade da cultura da batata cv. Monalisa, irrigada por gotejamento, conduzida em parcelas com o plantio tradicional em linhas simples (LS), espaçadas de 0,75 m, e em linhas duplas (LD), com espaçamentos alternados de 0,60 e 0,90 m, dispostos em blocos ao acaso, com oito repetições. O cultivo em LS recebeu uma linha de tubogotejador por linha de plantas, enquanto no cultivo em LD, o tubogotejador foi instalado entre as linhas de menor espaçamento. O plantio da batata foi realizado em 19 de abril de 2005, e a colheita, em 15 de agosto de 2005, em Itobi - SP, sendo a mesma densidade de plantio nos dois tratamentos. A matéria seca da parte aérea e o índice de área foliar não diferiram estatisticamente nos dois sistemas de cultivo. O sistema de plantio em LD proporcionou maior produtividade de batatas, comparado ao sistema em LS. A qualidade da produção foi semelhante em ambos os sistemas de cultivo.

Tratamento anaeróbio de águas residuárias do beneficiamento de café por via úmida em reatores UASB em dois estágios

Neste trabalho, avaliou-se a eficiência do tratamento de águas residuárias do beneficiamento de café por via úmida em reatores anaeróbios de fluxo ascendente com manta de lodo (UASB), em dois estágios, em escala de bancada, submetidos a tempos de detenção hidráulica (TDH) de 4,0; 5,2 e 6,2 dias e cargas orgânicas volumétricas (COV) de 5,8; 3,0 e 3,6 g DQO total (L d)-1, no primeiro reator (R1), e TDH de 2,0; 2,6 e 3,1 dias e COV de 5,8; 0,5 e 0,4 g DQO total (L d)-1, no segundo reator (R2). Os valores médios de DQO do afluente variaram de 15.440 a 23.040 mg O2 L-1. As eficiências médias de remoção de DQO total e SST foram de 66 a 98% e de 93 a 97%, respectivamente, nos reatores UASB, em dois estágios. O teor médio de metano no biogás variou de 69 a 89%, no reator R1, e de 52 a 73%, no reator R2. A produção volumétrica máxima de metano de 0,708 L CH4 (L reator d)-1 foi obtida com COV de 3,6 g DQO (Ld)-1 e TDH de 6,2 d, no reator R1. Os valores médios de pH variaram de 4,7 a 7,7 e de 4,9 a 8,0 nos efluentes dos reatores R1 e R2, respectivamente. As concentrações de ácidos voláteis totais nos efluentes mantiveram-se estáveis com valores inferiores a 100 mg L-1, com TDH de 5,2 e 6,2 dias, no reator R1, e TDH de 2,6 e 3,1 dias, no reator R2. As concentrações médias de fenóis totais no afluente variaram de 80 a 97 mg L-1 e as eficiências médias de remoção nos reatores UASB, em dois estágios, foram de 72 a 90%.

Development of capacitive sensor for measuring soil water content

The irrigation management based on the monitoring of the soil water content allows for the minimization of the amount of water applied, making its use more efficient. Taking into account these aspects, in this work, a sensor for measuring the soil water content was developed to allow real time automation of irrigation systems. This way, problems affecting crop yielding such as irregularities in the time to turn on or turn off the pump, and excess or deficit of water can be solved. To develop the sensors were used stainless steel rods, resin, and insulating varnish. The sensors measuring circuit was based on a microcontroller, which gives its output signal in the digital format. The sensors were calibrated using soil of the type “Quartzarenic Neosoil”. A third order polynomial model was fitted to the experimental data between the values of water content corresponding to the field capacity and the wilting point to correlate the soil water content obtained by the oven standard method with those measured by the electronic circuit, with a coefficient of determination of 93.17%, and an accuracy in the measures of ±0.010 kg kg-1. Based on the results, it was concluded that the sensor and its implemented measuring circuit can be used in the automation process of irrigation systems.

Integrating professional education, research and extensionin irrigated agriculture technology centers

With the objective to stimulate the use of irrigation and the electric energy fee reduction during night time program granted by the 2004 Federal law, the Government of the state of Paraná, Brazil launched the Night Irrigation Program - NPI. Beyond this discount, the farmer that adheres to NPI will get additional benefits, as completion of the electric grid without cost, subsidized financing of equipment, technical assistance, support with environmental farm compliance, and the possibility of replacing the entire pump energy matrix. As part of the NPI strategy of action, installation of learning centers for irrigation technology was planned in agricultural schools, thus contributing both to improve technical professional training in agriculture, and for the dissemination of knowledge in irrigated agriculture, in order to increase agricultural productivity.

Potassium distribution in drip irrigation with fertigation for different injection distances in the main line

The purpose of this research was to evaluate the K2O distribution uniformity by surface drip irrigation at Universitat Politecnica de Valencia, Valencia, Spain (39º 29′ N, 0º 23′ W, 20 m). The irrigation was performed by drip lines with not-compensated emitters, spaced 0.3 m. The fertigation was realized using a fertilizer injector pump of electric action with injection of 0.25 h. The experimental design used completely randomized blocks with five treatments and four replications. The treatments consisted of injection in five distances, located at 10; 20; 30; 40; 50 m of the first drip line. Samples were collected in emitters located at the start, at 1/3, at 2/3 and at the end of the drip lines. The nutrient concentration was determined by flame spectrophotometry. The Christiansen's uniformity coefficients (CUC), of distribution (DUC), of statistical (SUC) and of emission (eUC) were estimated. The K2O concentration and distribution decreased linearly with the increase of the injection distance. In all treatments, the CUC, SUC and DUC were described as 'excellent'. The eUC was described as 'recommended' only at smaller injection distances.

En gestaltning av individens erfarenhetsbaserade kunskap inom diabetesvården

The aim of this study is to form the experience-based knowledge of diabetics. The broader intent is to be able to transform this experience-based knowledge as an asset within caring. In this study, a theoretical contact for the empirical data is presented through phronesis, i.e. practical wisdom. Phronesis can be seen as the most suitable form of knowledge to be able to deepen the individual's understanding of experiencebased knowledge. For this research, hermeneutic phenomenology was chosen. Abductive reasoning was the method chosen to approach the data collected through repeated deep interviews with individuals with personal experience of diabetes and the use of insulin pumps. The abductive approach fascilitates a broader interpretation of the primary empirical results via a theory of philosophy of science, such as phronesis, the life-world and the negativity of the experience. The latent message of the empirical data is thereby also additionally highlighted. The synthesis reveals that experience-based knowledge arrives with time, it is personified and praxis-oriented, and before this time, the knowledge and security must be provided by the established care, by people close to the individual or by other external sources. The experience-based knowledge has strenghts and weaknesses. The knowledge is further categorized by the individual's ability to discern and make judgement. Additionally, the experience-based kowledge is a reflecting and action-based knowledge striving to improve the care provided. The experience-based knowledge held by the individual is potentially a great instrument towards improving general knowledge with possible practical applications within the diabetic care. Furthermost, in practical suggestions to fascilitate care. In generally applying knowledge gathered from the individual's experiental point of view, there are inherent risks. These risks could potentially be eliminated through the adoption of a concept where the established care could function as a quality guarantor. A concept taking into account the experiencebased knowledge as a source of information and knowledge in the care for diabetics. Co-created knowledge and understanding is a position found in both self-care and pump-treatment. It is also found through the optimal application of the experience-based knowledge of the individual as well as the knowledge found within the established care, in order to fascilitate well-being. This as expressed by the individual's phronesis-based knowledge.

Papel da laparoscopia no trauma abdominal penetrante

OBJETIVO: O papel da laparoscopia na redução da taxa de laparotomias não-terapêuticas e da morbidade em pacientes vítimas de trauma abdominal penetrante tem sido amplamente discutido durante os últimos anos. O objetivo do presente estudo é relatar a experiência inicial de um hospital universitário no manejo laparoscópico de pacientes com trauma abdominal penetrante. MÉTODO: Durante um período de três anos, a laparoscopia foi realizada em 37 pacientes vítimas de trauma abdominal penetrante, hemodinamicamente estáveis. Os prontuários médicos foram revisados e os parâmetros analisados foram as indicações do procedimento, lesões associadas, necessidade de conversão, tempo de permanência hospitalar e complicações. RESULTADOS: Houve 18 (48,6%) casos de laparoscopias diagnósticas (LD) positivas e 19 (51,4%) negativas. Dos pacientes com LD positiva, oito (44,4%) foram submetidos à laparotomia exploradora com finalidade terapêutica ou para melhor delineamento da lesão. Houve 10 (55,6%) LD positivas nas quais não foi realizada conversão para cirurgia aberta. Quatro pacientes apresentaram lesões reparáveis laparoscopicamente, sendo realizado hepatorrafia (n=2) e frenorrafia (n=2). Os outros seis pacientes apresentavam lesões isoladas sem sangramento ativo, e a laparotomia não-terapêutica foi evitada. Os pacientes receberam dieta no primeiro dia de pós-operatório e o tempo médio de hospitalização foi de 3,8 dias. CONCLUSÕES: Nossa experiência inicial confirma que a laparoscopia é um bom método de avaliação e tratamento no trauma penetrante. A morbidade relacionada à laparotomias desnecessárias pode ser minimizada quando o procedimento é bem indicado, e o tratamento pode ser realizado com sucesso em casos selecionados.

Aspectos endoscópicos no manejo da úlcera péptica gastroduodenal

Bleeding remains a common and a potential lethal complication for peptic ulcer disease. Multidisciplinary approach by endoscopists, surgeons and intensive care physicians is necessary to improve results for this severe complication. In this article we intend to introduce surgeons and intensive care physicians to endoscopic concepts and maneuvers commonly used in the treatment of bleeding peptic ulcer disease. Early clinical assessment and endoscopic evaluation are helpful to classify the severity of the bleeding episode. Two major achievements have changed the management of this complication: combined endoscopic therapy and proton pump inhibitors. The former consists of combining two different endoscopic methods to stop bleeding or prevent re-bleeding (e.g., injection of a sclerosing substance and thermal coagulation). Surgical treatment for peptic ulcer bleeding is indicated when endoscopic therapy fails or to prevent re-bleeding in high risk patients who presents with a spurting bleeding ulcer and shock. For the remaining situations, there are consistent evidences that a second endoscopic therapy should be attempted when re-bleeding occurs. Keywords: endoscopic hemostasis, recurrent bleeding, peptic ulcer bleeding, proton-pump inhibitor, non-variceal gastrointestinal bleeding.

Esophagectomy with gastroplasty in advanced megaesophagus: late results of omeprazole use

Objective: To analyze the late results of advanced Chagasic megaesophagus treatment by esophagectomy associated with the use of proton pump inhibitor (omeprazole) as for the incidence of esophagitis and Barrett's esophagus in the remaining stump. Methods : We studied patients with advanced megaesophagus undergoing esophagectomy and transmediastinal esophagogastroplasty. Patients were divided into three groups: A (20) with esophageal replacement by full stomach, without the use of omeprazole; B (20) with esophageal replacement by full stomach, with omeprazole 40 mg/day introduced after the first postoperative endoscopy and maintained for six years; and C (30) with esophageal replacement by gastric tube with use of omeprazole. Dysphagia, weight loss and BMI were clinical parameters we analyzed. Upper gastrointestinal endoscopy was performed in all patients, and determined the height of the anastomosis, the aspect of the mucosa, with special attention to possible injuries arising from gastroesophageal reflux, and the patency of the esophagogastric anastomosis. Results : We studied 50 patients, 28 males (56%) and 22 (44%) females. All underwent endoscopy every year. In the first endoscopy, erosive esophagitis was present in nine patients (18%) and Barrett's esophagus, in four (8%); in the last endoscopy, erosive esophagitis was present in five patients (8%) and Barrett's esophagus in one (2%). When comparing groups B and C, there was no evidence that the manufacturing of a gastric tube reduced esophagitis and Barrett's esophagus. However, when comparing groups A and C, omeprazole use was correlated with reduction of reflux complications such as esophagitis and Barrett's esophagus (p <0.005). Conclusion : The use of omeprazole (40 mg/day) reduced the onset of erosive esophagitis and Barrett's esophagus during the late postoperative period.