928 resultados para Irrigation system design
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Background: Burnout syndrome (BS) is increasing among health professionals, including family doctors (FD). Aim: To characterize the prevalence of BS in a sample of FDs working in the Portuguese National Health System. Design: Cross-sectional survey. Setting: Primary Health Care Centers (HCC) from the 18 continental districts and 2 archipelagos of Portugal. Method: The Portuguese version of the Maslach Burnout Inventory - Human Services Survey (MBI - HSS) was sent to 40 randomly selected health-care centers (HCC) and distributed to the FDs employed. Sociodemographic and work-related data was also collected. Participants were classified as having high, average or low levels of emotional exhaustion (EE), depersonalization (DP) and personal accomplishment (PA) dimensions of burnout. Results: 371 questionnaires were sent, of which 153 (83 women, age range 29-64 years; response rate 41%) returned. One quarter (25.5%) of participants had high EE, 10.1% high DP and 11.4% high PA, but only 2.0% of participants scored high for all three dimensions. Women had significantly higher DP and PA scores than men; increased daily workload also led to increased PA scores. Conversely, no association was found between BS scores and age, marital status, number of years of practice or type of HCC (Family or Personalized). Conclusion: High burnout is relatively common among Portuguese family doctors, yet slightly lower than reported for other European countries. Burnout relief measures should be developed in order to prevent a further increase of BS among Portuguese FDs.
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A informação sobre a formação do custo de produção, a produtividade e conhecimento dos elementos que formam o custo de produção, são fundamentais para a tomada de decisão dos agricultores na adopção de técnicas para a realização das suas actividades agrícolas. Com este trabalho pretende-se analisar a produção, o custo de produção e os níveis de rentabilidade das culturas de tomate, repolho e cenoura comparativamente às duas tecnologias de rega utilizadas, nas condições do cultivo do agricultor da Ilha de Santiago. Para isso foi concebido uma ficha de inquérito, na qual foi registadas todas as informações técnicas e económicas junto dos agricultores referente às culturas mencionadas, à medida que vem se efectuando visitas as suas explorações agrícolas. Os resultados demonstram que produzir cenoura no sistema gota-gota garantam maior produtividade em relação ao sistema tradicional. O mesmo não se pode dizer em relação ao tomate e repolho. Em relação ao custo de produção comparativamente às tecnologias de rega a analise estatística não acusou diferenças significativas. Os resultados demonstram ainda que a produção das citadas culturas em ambas tecnologias é rentável e com a economia de água na ordem dos 50% quando as mesmas são praticadas no sistema gota-gota. Entretanto, concluiu-se que o rendimento do agricultor é determinado pelo nível de produção e pela época de produção, pois no período quente o preço de produtos em causa é mais elevado e consequentemente o produtor arrecada maior receita.
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The Neolithic was marked by a transition from small and relatively egalitarian groups to much larger groups with increased stratification. But, the dynamics of this remain poorly understood. It is hard to see how despotism can arise without coercion, yet coercion could not easily have occurred in an egalitarian setting. Using a quantitative model of evolution in a patch-structured population, we demonstrate that the interaction between demographic and ecological factors can overcome this conundrum. We model the coevolution of individual preferences for hierarchy alongside the degree of despotism of leaders, and the dispersal preferences of followers. We show that voluntary leadership without coercion can evolve in small groups, when leaders help to solve coordination problems related to resource production. An example is coordinating construction of an irrigation system. Our model predicts that the transition to larger despotic groups will then occur when: (i) surplus resources lead to demographic expansion of groups, removing the viability of an acephalous niche in the same area and so locking individuals into hierarchy; (ii) high dispersal costs limit followers' ability to escape a despot. Empirical evidence suggests that these conditions were probably met, for the first time, during the subsistence intensification of the Neolithic.
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AIM: To characterise the prevalence of burnout syndrome in a sample of family doctors (FDs) working in the Portuguese National Health System. DESIGN: Cross-sectional survey. SETTING: Primary healthcare centres from the 18 continental districts and two archipelagos of Portugal. METHOD: The Portuguese version of the Maslach Burnout Inventory-Human Services Survey was sent to 40 randomly selected healthcare centres and distributed to the FDs employed. Socio-demographic and work-related data were also collected. Participants were classified as having high, average or low levels of emotional exhaustion (EE), depersonalisation (DP) and personal accomplishment (PA) dimensions of burnout. RESULTS: 371 questionnaires were sent, of which 153 (83 women, age range 29-64 years; response rate 41%) returned. One-quarter (25.3%, 95% CI 18.6% to 33.1%) of FDs scored high for EE, 16.2% (10.7% to 23.2%) for DP and 16.7% (11.1% to 23.6%) for lack of PA. On multivariate analysis, being married, of older age, having many years of practice or working in a personalised healthcare unit tended to be associated with increased burnout components. Men tended to present higher EE and DP but lower lack of PA than women. Finally, the prevalence (95% CI) of burnout ranged between 4.1% (1.5% to 8.6%) and 32.4% (25.0% to 40.6%), depending on the definition used. CONCLUSIONS: High burnout is relatively common among Portuguese FDs. Burnout relief measures should be developed in order to prevent a further increase of burnout syndrome among Portuguese FDs.
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Las tecnologías multiplataforma y multicanal permiten la movilidad de la información, cosa que tiene una incidencia directa sobre la evolución del libro electrónico. El cambio viene dado por la aparición de una nueva generación de dispositivos de tinta electrónica, así como por los propios modelos de gestión de la información. En el presente trabajo se revisa el concepto de libro electrónico y se presentan las características básicas de los dispositivos que se pueden encontrar en el mercado, para a continuación exponer los elementos necesarios para la ejecución de proyectos de producción de obras para dispositivos de tinta electrónica.
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BACKGROUND: Previous published studies have shown significant variations in colonoscopy performance, even when medical factors are taken into account. This study aimed to examine the role of nonmedical factors (ie, embodied in health care system design) as possible contributors to variations in colonoscopy performance. METHODS: Patient data from a multicenter observational study conducted between 2000 and 2002 in 21 centers in 11 western countries were used. Variability was captured through 2 performance outcomes (diagnostic yield and colonoscopy withdrawal time), jointly studied as dependent variables, using a multilevel 2-equation system. RESULTS: Results showed that open-access systems and high-volume colonoscopy centers were independently associated with a higher likelihood of detecting significant lesions and longer withdrawal durations. Fee for service (FFS) payment was associated with shorter withdrawal durations, and so had an indirect negative impact on the diagnostic yield. Teaching centers exhibited lower detection rates and longer withdrawal times. CONCLUSIONS: Our results suggest that gatekeeping colonoscopy is likely to miss patients with significant lesions and that developing specialized colonoscopy units is important to improve performance. Results also suggest that FFS may result in a lower quality of care in colonoscopy practice and highlight the fact that longer withdrawal times do not necessarily indicate higher quality in teaching centers.
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This report documents work undertaken in the demonstration of a low-cost Automatic Weight and Classification System (AWACS). An AWACS procurement specification and details of the results of the project are also included. The intent of the project is to support and encourage transferring research knowledge to state and local agencies and manufacturers through field demonstrations. Presently available, Weigh-in-Motion and Classification Systems are typically too expensive to permit the wide deployment necessary to obtain representative vehicle data. Piezo electric technology has been used in the United Kingdom and Europe and is believed to be the basic element in a low-cost AWACS. Low-cost systems have been installed at two sites, one in Portland Cement Concrete (PCC) pavement in Iowa and the other in Asphaltic Cement Concrete (ACC) pavement in Minnesota to provide experience with both types of pavement. The systems provide axle weights, gross vehicle weight, axle spacing, vehicle classification, vehicle speed, vehicle count, and time of arrival. In addition, system self-calibration and a method to predict contact tire pressure is included in the system design. The study has shown that in the PCC pavement, the AWACS is capable of meeting the needs of state and federal highway agencies, producing accuracies comparable to many current commercial WIM devices. This is being achieved at a procurement cost of substantially less than currently available equipment. In the ACC pavement the accuracies were less than those observed in the PCC pavement which is concluded to result from a low pavement rigidity at this site. Further work is needed to assess the AWACS performance at a range of sites in ACC pavements.
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A good system of preventive bridge maintenance enhances the ability of engineers to manage and monitor bridge conditions, and take proper action at the right time. Traditionally infrastructure inspection is performed via infrequent periodical visual inspection in the field. Wireless sensor technology provides an alternative cost-effective approach for constant monitoring of infrastructures. Scientific data-acquisition systems make reliable structural measurements, even in inaccessible and harsh environments by using wireless sensors. With advances in sensor technology and availability of low cost integrated circuits, a wireless monitoring sensor network has been considered to be the new generation technology for structural health monitoring. The main goal of this project was to implement a wireless sensor network for monitoring the behavior and integrity of highway bridges. At the core of the system is a low-cost, low power wireless strain sensor node whose hardware design is optimized for structural monitoring applications. The key components of the systems are the control unit, sensors, software and communication capability. The extensive information developed for each of these areas has been used to design the system. The performance and reliability of the proposed wireless monitoring system is validated on a 34 feet span composite beam in slab bridge in Black Hawk County, Iowa. The micro strain data is successfully extracted from output-only response collected by the wireless monitoring system. The energy efficiency of the system was investigated to estimate the battery lifetime of the wireless sensor nodes. This report also documents system design, the method used for data acquisition, and system validation and field testing. Recommendations on further implementation of wireless sensor networks for long term monitoring are provided.
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This abstract presents how we redesigned, with user-centred design methods, the way we organize and present the content on the UOC Virtual Library website. The content is now offered in a way that is more intuitive, usable and easy to understand, based on criteria of customization, transparency and proximity.The techniques used to achieve these objectives included benchmarking, interviews and focus groups during the user requirement capture phase and user tests to assess the process and results.
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Vanerin tai kertopuun valmistusprosessissaviilun kuivaukseen käytetään suurin osa koko valmistusprosessin primäärienergiasta. Viilunkuivauskoneessa viilun sisältämä vesi siirretään tyypillisesti prosessihöyryllä lämmitettyyn viilunkuivaajan kiertoilmaan höyrystämällä ja poistetaanviilunkuivaajasta poistoilman mukana. Viilunkuivaajan poistoilma on lämmintä jaerittäin suuren kosteuspitoisuutensa takia sisältää runsaasti energiaa. Tyypillisellä viilunkuivaajalla poistoilmaan sitoutunut lämpöteho vaihtelee prosessiolosuhteista riippuen välillä 2,7-5,7 MW. Diplomityössä tutkittiin viilunkuivaajan poistoilman sisältämän lämmön talteenottoa laitteistolla, johon kuuluu lämmöntalteenottopesuri, jossa poistoilmalla lämmitetään tuotantolaitoksen tukkipuun hautomon kiertovettä sekä ilma-ilma-lämmönsiirrin, jolla lämmitetään pesurista poistuvan ilman jäännöslämmöllä ulkoilmaa tehdassalin tuloilmakäyttöön. Työn tavoitteena oli kehittää lämmöntalteenottojärjestelmän suunnittelua, mitoitusta ja ajotapoja. Työssä analysoitiin teoreettisesti pesuria ja ilmalämmönsiirrintä, kehitettiin lämmöntalteenottopesurin simulointimenetelmä ja mitattiin toiminnassa olevia talteenottolaitteistoja. Tutkimuksessa todettiin lämmöntalteenottohyötysuhteen vaihtelevan lämmityskaudella välillä 50-70 %. Lämmöntalteenottolaitteiston pesurin veteen saatava teho riippuu ensisijaisesti viilunkuivaajan poistoilman lämpösisällöstä, joka on enimmäkseen kosteusriippuvainen ja ilmanvaihtoilmaan saatava teho ulkolämpö-tilan määräämästä tehontarpeesta. Pesurin vesijärjestelmän vaikutusmekanismit pesurin suorituskykyyn tunnistettiin ja niiden pohjalta annetaan suositukset mitoitukseen ja ajotapaan. Lämmöntalteenottolaitteiston lämpötehon tasapainottamiseen pesurin ja ilma-ilma-lämmönsiirtimen välillä mitoituksen avulla esitellään työkalut.
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Cooperative transmission can be seen as a "virtual" MIMO system, where themultiple transmit antennas are in fact implemented distributed by the antennas both at the source and the relay terminal. Depending on the system design, diversity/multiplexing gainsare achievable. This design involves the definition of the type of retransmission (incrementalredundancy, repetition coding), the design of the distributed space-time codes, the errorcorrecting scheme, the operation of the relay (decode&forward or amplify&forward) and thenumber of antennas at each terminal. Proposed schemes are evaluated in different conditionsin combination with forward error correcting codes (FEC), both for linear and near-optimum(sphere decoder) receivers, for its possible implementation in downlink high speed packetservices of cellular networks. Results show the benefits of coded cooperation over directtransmission in terms of increased throughput. It is shown that multiplexing gains areobserved even if the mobile station features a single antenna, provided that cell wide reuse of the relay radio resource is possible.
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Palvelukeskeiseen arkkitehtuuriin perustuvia järjestelmiä voidaan kehittää käyttämällä useita vaihtoehtoisia teknologioita. Toteuttamiseen parhaiten soveltuvia teknologioita ovat erilaiset standardikokoelmat, jotka tukevat useiden toisistaan toteutustavaltaan poikkeavien järjestelmien yhdistämistä käyttämällä standardeihin perustuvia rajapintoja. Täten kyseiset kokoelmat tukevat laajojen, useista erillisistä osista koostuvien palvelujärjestelmien kehittämistä. Tässä työssä selvitetään mikä palvelukeskeinen arkkitehtuuri on sekä millaisia komponentteja ja teknologioita kyseiseen arkkitehtuuriin perustuvan palvelujärjestelmän toteuttamiseen tarvitaan. Tavoitteena on esitellä palvelukeskeinen arkkitehtuuri ja siihen liittyvät teknologiat sekä suunnitella korkealla tasolla kyseisiä teknologioita hyödyntävä integraatioalusta käyttäjien ja useiden palvelun tarjoajien yhdistämiseksi. Työn tuloksena syntyvän teknologiaselvitysraportin selvitysluonteen vuoksi työssä ei suunnitella tarkasti toteutettavaa järjestelmää vaan ainoastaanpohjustetaan järjestelmän suunnittelua sekä esitellään siihen liittyviä arkkitehtuuri- ja toteutusmahdollisuuksia. Internet-pohjainen palvelukeskeiseen arkkitehtuuriin perustuva järjestelmä voi perustua suoriinverkon välisiin yhteyksiin tai vaihtoehtoisesti erityyppisiin välitason sovelluksiin. Välitason sovellukset mahdollistavat niiden tyypistä riippuen järjestelmän erilaisten lisäominaisuuksien toteuttamisen ja tukevat useita yleisimpiä palvelukeskeisiä teknologioita. Työn tuloksena syntyneen teknologiaselvityksen perusteella näistä teknologioista Web-palvelu -arkkitehtuuri ja siihen liittyvät menetelmät soveltuvat parhaiten suunniteltavan järjestelmän rakenneosiksi. Järjestelmän tarkemmat toteutustavat riippuvat myöhemmin määriteltävistä yksityiskohtaisista vaatimuksista sekä valittavasta välitason ohjelmiston toteutuksesta.
Resumo:
This abstract presents how we redesigned, with user-centred design methods, the way we organize and present the content on the UOC Virtual Library website. The content is now offered in a way that is more intuitive, usable and easy to understand, based on criteria of customization, transparency and proximity.The techniques used to achieve these objectives included benchmarking, interviews and focus groups during the user requirement capture phase and user tests to assess the process and results.
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Tämän työn tavoitteena on suunnitella yksinkertainen Internet-pohjainen mielipidekyselyjärjestelmä sekä esitellä yksityiskohtaisesti järjestelmän toteutus ja siihen liittyvät menetelmät. Menetelmistäesitellään ainoastaan ennalta valitut menetelmät järjestelmän toteutukseen, tietojen esittämiseen, esitystavan muotoiluun sekä tietojen varastointiin. Järjestelmä toteutetaan HTML- ja PHP-kielillä sekä käyttämällä CSS-menetelmän tyylimuotoiluja ja XML-kielen muotoiluun perustuvia tiedostoja tietovarastoina. Järjestelmän suunnitteluun liittyen työssä pyritään kuvaamaan järjestelmään toteutettavat kaksi erillistä käyttöliittymää, pääkäyttäjän käyttöliittymä ja normaalin käyttäjän käyttöliittymä, sekä näihin toteutettavat toiminnot. Pääkäyttäjän tärkeimmät toiminnot ovat mielipidekyselyiden luominen, käyttäjien lisääminen kyselyihin sekä kyselyiden tulosten seuranta. Normaalin käyttäjän toiminnot taas rajoittuvat kirjautumiseen ja kyselyyn vastaamiseen. Järjestelmän toteutuksen kuvauksessa kuvataan tarkasti edellä mainittujen kahden käyttöliittymän toiminnot sekä näiden toimintojen toteutustavat. Lisäksi toteutuksen kuvauksen yhteydessä määritellään tarkasti järjestelmän tietovarastoina toimivien tiedostojen sisällön muoto. Työn lopputuloksena syntyi valituilla toteutustavoilla toteutettu toimiva mielipidekyselyjärjestelmä sekä tämä järjestelmän suunnitteluun ja toteutuksen selvittämiseen keskittynyt dokumentti. Toteutetusta järjestelmästä ei tullut täydellinen vaan jatkokehityksessä voidaan harkita esimerkiksi tietokannan käyttämistä järjestelmän tietovarastoina sekä joidenkin lisäominaisuuksien toteuttamista. Tavoitteeseen päästiin kuitenkin, sillä toteutettu järjestelmä on toimiva ja käyttötarkoitukseensa sopiva.
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The changing business environment demands that chemical industrial processes be designed such that they enable the attainment of multi-objective requirements and the enhancement of innovativedesign activities. The requirements and key issues for conceptual process synthesis have changed and are no longer those of conventional process design; there is an increased emphasis on innovative research to develop new concepts, novel techniques and processes. A central issue, how to enhance the creativity of the design process, requires further research into methodologies. The thesis presentsa conflict-based methodology for conceptual process synthesis. The motivation of the work is to support decision-making in design and synthesis and to enhance the creativity of design activities. It deals with the multi-objective requirements and combinatorially complex nature of process synthesis. The work is carriedout based on a new concept and design paradigm adapted from Theory of InventiveProblem Solving methodology (TRIZ). TRIZ is claimed to be a `systematic creativity' framework thanks to its knowledge based and evolutionary-directed nature. The conflict concept, when applied to process synthesis, throws new lights on design problems and activities. The conflict model is proposed as a way of describing design problems and handling design information. The design tasks are represented as groups of conflicts and conflict table is built as the design tool. The general design paradigm is formulated to handle conflicts in both the early and detailed design stages. The methodology developed reflects the conflict nature of process design and synthesis. The method is implemented and verified through case studies of distillation system design, reactor/separator network design and waste minimization. Handling the various levels of conflicts evolve possible design alternatives in a systematic procedure which consists of establishing an efficient and compact solution space for the detailed design stage. The approach also provides the information to bridge the gap between the application of qualitative knowledge in the early stage and quantitative techniques in the detailed design stage. Enhancement of creativity is realized through the better understanding of the design problems gained from the conflict concept and in the improvement in engineering design practice via the systematic nature of the approach.