Backpressure effects on the flow-pressure relation of driplines

ABSTRACT For drip irrigation design and management, it is necessary to know the relation between flow and pressure acting on emitters. In the case of subsurface drip irrigation, the backpressure phenomenon may change the hydraulic characteristics of emitters. Thus, this study aimed at determining such relationship between flow and pressure of different driplines in surface and subsurface conditions; aiming to find possible differences in hydraulic behavior. We tested four emitter types; two pressure compensating (D5000 and Hydro PCND) and two non-pressure compensating (TalDrip and Jardiline). Emitter flow rates were attained in atmospheric conditions and submerged in water, in which submergence levels represented backpressure. Assays were performed using inlet pressures of 80, 100, 120, and 150 kPa for the Hydro PCND dripline and 25, 50, 100, and 150 kPa for the other ones; the backpressures were of 0.49, 1.47, 2.45, 4.41 and 6.37 kPa with four replications. The emitters had their proportionality constants and discharge exponents changed in submerged applications, representing backpressure effect. Non-pressure compensating emitters had their discharge exponent decreased, while in pressure compensating ones, it was increased. Backpressure reduced emitter flow rates at all evaluated pressures.

Volvo da vesícula biliar

A case of torsion of the gallbladder is presented. This is a rare condition that occurs when it is associated with anatomical variants related to abnormal fixation of the gallbladder to the liver bed. The blood irrigation is insufficient and the gallbladder develops necrosis. The abnormal implantation occurs in 4% of the population. If the gallbladder losses its fixations to the inferior margin of the liver with the presence of a 1011.g mesocyst a torsion can occur when this gallbladder twists axially with subsequent occlusion of the blood flow. The signs and symptoms are similar to those of severe acute cholecystitis: abrupt onset of the pain and large palpable mass below the right costal margin. The ultrasound can show a very large and anteriorly floating gallbladder: In this case, the ultrasound did not show any abnormal signs, so it is usually diagnosed at laparotomy and the treatement consists of cholecystectomy. This condition should be suspected in acute abdominal pain of unknown origin.

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.

Pseudomixoma peritoneal: abordagem cirúrgica em dois casos

The authors report the surgical procedure in two patients with pseudomyxoma peritonei, histologically considered as mucinous adenocarcinoma. In both patients, intestinal loops and other visceras were blocked and it was not possible to localize the tumor's origin. There was, in both cases, a great volume of mucinous ascitis. In the first patient a laparotomy was performed and a drainage by a five centimeters peritoneostomy in the abdominal upper left quadrant. In the second just a peritoneostomy was performed in the same location. The sequential irrigation of the abdominal cavity controlled the ascitis in a few days. Certainly this approach avoided a second procedure to clean the mucinous ascitis.

Linfoma esofágico primário

We describe the case of a 54 year old woman seen with an esophageal mass diagnosed as a primary esophageal lymphoma. The main symptom was dysphagia of seven months duration. The treatment consisted in resection of the tumor, and reconstruction of the defect with a reversed pleural flap, followed by a chemotherapy regimen that consisted of five drugs, cyclophosphamid, prednisone, doxorubicin, rituximab and vincristine (R-CHOP). The patient developed an esophageal pleural fistula treated with pleural drainage and irrigation that closed in 45 days. Two and one half years later she is doing well and disease free.

Prosessihöyryn tuotannon kustannusoptimointi

Tässä työssä on tutkittu prosessihöyryn tuotantokustannusten optimointia Neste Oil Oy:n Naantalin jalostamolla. Työssä on keskitytty ennen kaikkea prosessi-höyryn tuotantoon öljynjalostamolla. Tavoitteena oli luoda yksinkertainen työkalu, jonka avulla voidaan vertailla höyryntuotantokustannuksia jalostamon tuotan-toyksiköissä. Samalla oli tarkoituksena kartoittaa höyryn tuotantomahdollisuudet yksiköissä. Työn tuloksena tehty Excel-pohjainen laskentataulukko on esitelty tässä työssä. Ohjelman tarkkuutta on mahdollista parantaa prosessikoeajojen avul-la. Jo nykyisellä laskentatarkkuudella ohjelma täyttää kuitenkin asetetut tavoitteet eli antaa mahdollisuuden vertailla helposti ja havainnollisesti tuotantokustannuksia yksiköiden välillä. Oman höyryntuotannon lisäksi Naantalin jalostamo ostaa höyryä viereiseltä Fortumin Naantalin voimalaitokselta. Ostohöyryn hinta on las-kettu työkalussa mukaan vertailuun. Työn perusteella ostohöyry on Naantalin ja-lostamon tapauksessa selkeästi omatuotantoa edullisempi vaihtoehto. Ero kustan-nuksissa syntyy käytettävästä polttoaineesta, joka jalostamon tapauksessa on ja-lostamo- eli polttokaasu. Nykyisen tasoisella raakaöljyn hinnalla tilanne säilynee tällaisena tulevaisuudessakin. Jalostamolta löytyi myös kohteita, joissa energiatehokkuutta on mahdollista kehit-tää nykyisen höyryverkon ulkopuolella. Esimerkkeinä tällaisista kohteista tässä työssä on tarkasteltu toisen jätelämpökattilan rakentamista nykyisen toiminnassa olevan rinnalle, sekä höyryturbiinien asentamista paineenalennuslinjoihin. Näistä hankkeista jätelämpökattila osoittautui erittäin suositeltavaksi investoinniksi.

Working capital management in the small and medium-sized enterprises Case: Project-based business environment in Flowrox Oy

This Master´s thesis illustrates how growing a business ties up the company´s working capital and what the cost of committed capital. In order to manage a company´s working capital in rapid business growth phase, the thesis suggests that by monitoring and managing the operating and cash conversion cycles of customers´ projects, a company can find ways to secure the required amount of capital. The research method of this thesis was based on literature reviews and case study research. The theoretical review presents the concepts of working capital and provides the background for understanding how to improve working capital management. The company in subject is a global small and medium-sized enterprise that manufactures pumps and valves for demanding process conditions. The company is expanding, which creates lots of challenges. This thesis concentrates to the company´s working capital management and its efficiency through the supply chain and value chain perspective. The main elements of working capital management are inventory management, accounts receivable management and accounts payable management. Prepayments also play a significant role, particularly in project-based businesses. Developing companies´ working capital management requires knowledge from different kind of key operations´ in the company, like purchasing, production, sales, logistics and financing. The perspective to develop and describe working capital management is an operational. After literature reviews the thesis present pilot projects that formed the basis of a model to monitor working capital in the case company. Based on analysis and pilot projects, the thesis introduces a rough model for monitoring capital commitments in short time period. With the model the company can more efficiently monitor and manage their customer projects.

Automatic system identification and optimization of centrifugal pump operation

Centrifugal pumps are a notable end-consumer of electrical energy. Typical application of a centrifugal pump is the filling or emptying of a reservoir tank, where the pump is often operated at a constant speed until the process is completed. Installing a frequency converter to control the motor substitutes the traditional fixed-speed pumping system, allows the optimization of rotational speed profile for the pumping tasks and enables the estimation of rotational speed and shaft torque of an induction motor without any additional measurements from the motor shaft. Utilization of variable-speed operation provides the possibility to decrease the overall energy consumption of the pumping task. The static head of the pumping process may change during the pumping task. In such systems, the minimum rotational speed changes during reservoir filling or emptying, and the minimum energy consumption can’t be achieved with a fixed rotational speed. This thesis presents embedded algorithms to automatically identify, optimize and monitor pumping processes between supply and destination reservoirs, and evaluates the changing static head –based optimization method.

Lämpöpumppujen käytön potentiaali Suomessa

Tämä kandidaatintyö käsittelee lämpöpumppuja, niiden toimintaa ja niiden käytön tulevaisuutta. Työ on rajattu asuintalojen lämmittämiseen ja erityisesti käsitellään erillisiä pientaloja. Työn tavoite on esitellä lämpöpumppujen toimintaperiaate ja tekniikka, eri lämpöpumpputyypit ja niiden lämmönlähteet sekä lämpöpumppujen käyttöä rajoittavia tekijöitä. Lisäksi esitellään Suomen lämmitystapojen jakauma sekä pohditaan siihen tulevia muutoksia. Tilastojen pohjalta tehdään lopulta arvioita lämpöpumppujen käytön tulevaisuuden kehityksestä.

AT1-receptor mediated vascular damage in myocardium, kidneys and liver in rats

The systemic aspect of vascular damage induced by angiotensin II (ANG II) has been poorly explored in the literature. Considering the presence of ANG II and its specific receptor AT1, in several organs, all tissues might be potentially affected by its effects. The aims of this study were: To evaluate the early histological changes in the heart, liver and kidneys, produced by ANG II infusion, to evaluate the protective effect of losartan. Wistar rats were distributed into three groups: control (no treatment), treated with ANG II, and treated with ANG II + losartan. ANG II was continuously infused over 72 hours by subcutaneous osmotic pumps. Histological sections of the myocardium, kidneys and liver were stained and observed for the presence of necrosis. There were ANG II-induced perivascular inflammation and necrosis of the arteriolar wall in the myocardium, kidney, and liver by, which were partially prevented by losartan. There was no significant correlation between heart and kidney damage. Tissue lesion severity was lower than that of vascular lesions, without statistical difference between groups. ANG II causes vascular injury in the heart, kidneys and liver, indicating a systemic vasculotoxic effect; the mechanisms of damage/protection vary depending on the target organ; perivascular lesions may occur even when anti-hypertensive doses of losartan are used.

Characterization of capacitive sensors for measurements of the moisture in irrigated soils

The irrigation is a technique developed to supply the hydric needs of the plants. The use of the water should be optimized so that the culture just has enough for its growth, avoiding waste. The objective of this work was to characterize the behavior of capacitive sensors of humidity to monitor the moisture in the soils. In first instance, it was appraised sensors with dielectric built of synthetic pomes stone (Rd = 0,4 and Rd = 0,8) and of soil samples (Rd = 0,8 and Rd = 1,0), being the Rd parameter a geometric factor that relates the distance between the capacitor plates with radius of the plates. For the calibration, the sensors were installed in PVC recipient of cylindrical shape, filled with soil. The set (sensor and soil) was humidified by capillary effect and submitted by a natural drying very slowly. The parameter readings were taken daily, which allowed obtain the curves relating the humidity percentage, expressed in terms of dry weight, with the output voltage fort the sensor. The experiments were performed in sand soil and in dark red latossolo. The obtained results allowed to infer that the behavior of the sensor has a specific feature for each type of soil, being, therefore, necessary to develop a own calibration curve for the sensor, when used in soil with specific characteristic.

Häiriöanalyysejä tehonkorotetun kiehutusvesivoimalaitoksen käytettävyyden varmistamiseksi

TVO suunnittelee reaktoritehon 10 %:n korotusta Olkiluoto 1 ja 2 -voimalaitoksille. Reaktoriteho nostetaan 2500 MW:sta 2750 MW:iin polttoaineen rikastusastetta nostamalla ja pääkiertovirtausta kasvattamalla. Samalla syöttövesivirtaus reaktoriin ja tuorehöyryvirtaus turpiineille kasvaa. Lauhteenpuhdistusjärjestelmän kapasiteettia ei voida kuitenkaan kasvattaa, joten massavirran lisäys toteutetaan ottamalla käyttöön korkeapainesivulauhteen eteenpäinpumppaus. Lauhteen esilämmityslinjojen, lauhteenpuhdistuksen ja syöttövesipumppujen massavirta säilyy siten nykyisellään. Muita merkittäviä tehonkorotukseen liittyviä laitosmuutoksia ovat pääkiertopumppujen uusinta ja korkeapaineturpiinin muutokset. Tehonkorotetun prosessin käytettävyyden varmistamiseksi tehdään häiriöanalyysejä Apros-prosessisimulointiohjelmistoa käyttäen. OL1 ja OL2 -laitoksista on olemassa validoitu 2500 MW:n laitosmalli, josta muokatulla 2750 MW:n laitosmallilla simuloinnit tehdään. Häiriöanalyysien avulla selvitetään säätöjärjestelmien kyky pitää prosessin tila hallinnassa ilman suojausautomaation laukeamista. Simuloituihin tapauksiin kuuluu pumppujen ja venttiilien vikaantumistapauksia sekä turpiini- ja reaktoripuolen pikasulku- ja osittaispikasulkutapauksia. Myös meriveden lämpötilan vaikutusta häiriötilanteisiin tarkastellaan. Analyysien perusteella voimalaitosten ohjaus- ja suojausautomaatio toimivat hyvin myös korotetulla teholla. Tehonkorotuksen jälkeiset suuremmat massavirrat aiheuttavat kuitenkin voimakkaampia reaktoripaineen ja -tehon vaihteluita varsinkin venttiilien sulkeutumistapauksissa. Simuloinnit osoittivat, että tehonkorotus 2500 MW:sta 2750 MW:iin on mahdollinen, mutta aiheuttaa pieniä muutoksia laitoksen suojausjärjestelmien laukaisurajoihin.

Suurnopeuspumput

Suurnopeustekniikasta on tehty tutkimusta 1980-luvulta lähtien. On havaittu, että tiettyjen energiateknisten sovellusten hyötysuhde paranee, kun käytetään selkeästi tavanomaista suurempaa pyörimisnopeutta. Suurnopeuspumppuja on totuttu näkemään lähinnä erikoiskohteissa, kuten avaruustekniikassa. Tämän työn tarkoituksena on kartoittaa, voiko suurnopeuspumppuja käyttää tavallisissa teollisuussovelluksissa, joissa tarvitaan korkeapaineista vettä. Työssä selvitetään pumppujen laskentaan ja valintaan liittyvää käsitteistöä, sekä luodaan kirjallisuuskatsaus suurnopeuspumppujen kehitykseen. Työn tarkoituksena on myöskin luoda valmiuksia suurnopeuspumppujen tutkimukseen ja arviointiin.

Weed control and green ear yield in maize

The objective of this work was to evaluate the influence of weeding frequency on cultivar Centralmex green corn yield. Two experiments were conducted in Mossoró-RN (Brazil), with the use of sprinkler irrigation. A random block design with four replicates was used. It was observed that the total number and weight (TW) of unhusked green ears, the number and weight of marketable unhusked ears and the number and weight of marketable husked ears were reduced under no weeding treatment. The number timing of weedings did not influence green corn yield, except for one weeding at 60 DAP, which was equivalent to the "no weeding" treatment, for TW. When maize is marketed considering the total number of green ears, higher net income is obtained when one weeding is carried out 45 days after planting.

Energy-efficient control strategies for variable speed driven parallel pumping systems based on pump operation point monitoring with frequency converters

The pumping processes requiring wide range of flow are often equipped with parallelconnected centrifugal pumps. In parallel pumping systems, the use of variable speed control allows that the required output for the process can be delivered with a varying number of operated pump units and selected rotational speed references. However, the optimization of the parallel-connected rotational speed controlled pump units often requires adaptive modelling of both parallel pump characteristics and the surrounding system in varying operation conditions. The available information required for the system modelling in typical parallel pumping applications such as waste water treatment and various cooling and water delivery pumping tasks can be limited, and the lack of real-time operation point monitoring often sets limits for accurate energy efficiency optimization. Hence, alternatives for easily implementable control strategies which can be adopted with minimum system data are necessary. This doctoral thesis concentrates on the methods that allow the energy efficient use of variable speed controlled parallel pumps in system scenarios in which the parallel pump units consist of a centrifugal pump, an electric motor, and a frequency converter. Firstly, the suitable operation conditions for variable speed controlled parallel pumps are studied. Secondly, methods for determining the output of each parallel pump unit using characteristic curve-based operation point estimation with frequency converter are discussed. Thirdly, the implementation of the control strategy based on real-time pump operation point estimation and sub-optimization of each parallel pump unit is studied. The findings of the thesis support the idea that the energy efficiency of the pumping can be increased without the installation of new, more efficient components in the systems by simply adopting suitable control strategies. An easily implementable and adaptive control strategy for variable speed controlled parallel pumping systems can be created by utilizing the pump operation point estimation available in modern frequency converters. Hence, additional real-time flow metering, start-up measurements, and detailed system model are unnecessary, and the pumping task can be fulfilled by determining a speed reference for each parallel-pump unit which suggests the energy efficient operation of the pumping system.