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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The marketing analysis of piggyback operations : with special emphasis on functional relationships /

Sleeper, David Chesley January 1965 (has links)
No description available.
2

Comparação das técnicas do piggyback com e sem oclusão da veia cava inferior em pacientes submetidos ao transplante ortotópico de fígado

SETTE, Marcelo José Antunes 31 January 2008 (has links)
Made available in DSpace on 2014-06-12T16:25:24Z (GMT). No. of bitstreams: 2 arquivo2069_1.pdf: 1456215 bytes, checksum: 985e87c2fe21aaea76f6f5e94a931ca8 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2008 / Objetivo: Comparar as técnicas de piggyback com e sem oclusão da veia cava inferior (OVCI) no transplante ortotópico de fígado (TOF). Pacientes e Método: Entre 2002 e 2005, 136 pacientes foram submetidos à TOF em dois hospitais um em Recife e outro em São Paulo, Brasil, sendo excluídos 36 pacientes. De acordo com a técnica de piggyback utilizada, os pacientes foram divididos em dois grupos: grupo A com OVCI = 47 pacientes; grupo B sem OVCI = 53 pacientes. Resultados: Não se observou diferença significante em relação ao sexo, idade, doença primaria do fígado, MELD e nem da função renal e hepática antes do TOF, quando se comparou os dois grupos. O estudo revelou que o tempo operatório foi 83,4 minutos a menos no grupo A em relação ao grupo B (grupo A = 7,13 ± 1,90 h e grupo B = 8,52 ± 1,90 h; p = 0,001), e requereu duas unidades de concentrados de hemácias a menos (grupo A = 3.63 ± 1.96 e grupo B = 5.63 ± 4.23 concentrado de hemácias; p = 0,016). Não se observou diferença significante entre os dois grupos referentes aos parâmetros hemodinâmicos durante a cirurgia, e nem em relação ao comprometimento da função hepática e renal no período de pós-operatório precoce. Conclusão: As duas técnicas foram semelhantes quando se avaliou os parâmetros hemodinâmicos no intra-operatório e os testes de função hepática e renal no pós-operatório precoce, no entanto a técnica de piggyback com OVCI foi executada em menor tempo cirúrgico e consumiu menos concentrados de hemácias
3

Biomechanical comparisons considering risk to the lumbar spine: walking with no load, a backpack, and a person on the back

Graham, Sheena 11 February 2015 (has links)
Participants were twelve 70+ kg male strength-trained athletes and one passenger child with a mass of 29 kg. The male participants walked three times over a force plate embedded in an eight metre walkway for each of three conditions: carrying no load, a 29 kg backpack, or a 29 kg passenger. Variables were compared using a repeated measures ANOVA test with a Bonferroni correction. Both load conditions produced compensatory trunk flexion; trunk flexion increased from no load to piggybacking to backpacking. Trunk range of motion was similar for no load and piggybacking, but increased to backpacking. The backpack load caused greater resultant and total magnitude of torque than the passenger load. The trunk extensors dominated with no load and piggybacking and the trunk flexors dominated with backpacking. Many of the significant differences between conditions suggest that piggybacking is biomechanically more similar to natural gait than is backpacking.
4

Transplante ortotópico de fígado sem desvio veno-venoso pelas técnicas convencional e piggyback

Sérgio Vieira de Melo, Paulo 31 January 2009 (has links)
Made available in DSpace on 2014-06-12T16:24:35Z (GMT). No. of bitstreams: 2 arquivo1354_1.pdf: 3344224 bytes, checksum: 930b951b851e2e5fbe0ea652b1000fba (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2009 / Introdução: O transplante ortotópico de fígado é amplamente utilizado no tratamento das doenças hepáticas irreversíveis e sem possibilidade de tratamento clínico. Na realização desse procedimento, ao se empregar a técnica convencional, a veia cava retro-hepática é removida juntamente com o fígado nativo. A veia cava inferior (VCI), portanto, permanece clampeada até a revascularização do enxerto e, nesse período, ocorre diminuição do retorno venoso, que pode induzir queda do débito cardíaco (em até 50%), instabilidade hemodinâmica e diminuição da pressão de perfusão renal. A utilização do sistema de desvio veno-venoso (DVV) porto-fêmoro-axilar, onde o sangue proveniente da veia femoral e da veia porta retorna ao coração, pela veia axilar, impulsionado por uma bomba centrífuga, tem como objetivo minimizar os efeitos do clampeamento da VCI. Na técnica piggyback, o fígado nativo é retirado preservando-se a veia cava do receptor, que é clampeada apenas parcialmente. O Serviço de Transplante Hepático dos hospitais Universitário Oswaldo Cruz e Jayme da Fonte têm empregado as duas técnicas sem a utilização do DVV há dez anos. O objetivo do presente estudo foi comparar os resultados com a utilização das duas técnicas. Casuística e Métodos: Foram analisados, retrospectivamente, 195 pacientes, transplantados entre 1999 e 2008, sendo 125 pela técnica convencional sem desvio veno-venoso (grupo CON) e 70 pela técnica piggyback (grupo PB). Os dados referentes aos receptores, no período pré-transplante, e aos doadores foram comparáveis. Analisaram-se parâmetros transoperatórios (tempo cirúrgico, tempo de isquemia, uso de hemoderivados e diurese), suporte de terapia intensiva (tempo de permanência e uso de drogas vasoativas), período de intubação, período de internamento hospitalar, função renal, função do enxerto, variação de peso, complicações pós-operatórias, retransplante e sobrevida dos pacientes. Resultados: O grupo PB apresentou redução do tempo cirúrgico, do tempo de isquemia total, do tempo de isquemia quente, do uso de concentrado de hemácias e plasma fresco, do tempo de internamento hospitalar e da mortalidade em 30 dias (p<0,05). Não houve diferença com relação à diurese transoperatória, ao tempo de permanência e ao uso de drogas vasoativas na UTI, ao período de intubação, à função renal, à função do enxerto, à variação de peso, à necessidade de reoperação, à incidência de sepse, às complicações biliares, às complicações vasculares, à necessidade de retransplante e à sobrevida atuarial de seis meses. Conclusão: O transplante ortotópico de fígado pode ser realizado sem DVV, com bons resultados, tanto pela técnica convencional quanto pela técnica piggyback. Desde que não haja contra-indicação técnica ou previsão de tempo de isquemia prolongado, a técnica piggyback deve ser preferida
5

Investigation on scour protection of submarine piggyback pipeline

Yang, S., Shi, B., Guo, Yakun, Yang, L. 08 May 2019 (has links)
Yes / This paper presents the results of laboratory experiments and numerical simulations to investigate the effect of different piggyback pipeline configuration on the morphology of local seabed scour subject to steady currents. Piggyback pipeline configuration investigated includes the commonly used piggyback pipeline, namely a small pipe attached on the top of large pipe and new form of piggyback pipeline proposed in this study in which a small pipe is attached to the large pipe on the upstream and downstream side, respectively. Pressure gradient, drag coefficient, lift coefficient and scour extent around pipelines are measured and analyzed for a range of pipelines and current conditions. Results show that the vortex strength downstream of the commonly used piggyback pipeline is larger than that for a single as well as the new piggyback pipeline under the same condition. This new type piggyback pipeline can effectively reduce the depth and width of the scour hole. In particular, when the ratio of the small pipe diameter over the large pipe diameter is greater than 0.3, little scour under this new type piggyback pipeline occurs for the test conditions. The bed topography downstream of the pipe has also been altered to favor the backfill. / National Natural Science Foundation of China (No. 51279189).
6

Caractérisation et facteurs de contrôle des distributions minéralogiques du Bassin Piggyback de Graus-Tremp-Ainsa (Espagne), à l’Eocène Inférieur. / Mineralogical distributions and associate controlling factors in the Graus-Tremp-Ainsa piggyback Basin (Spain) during the Early Eocene.

Chanvry, Emmanuelle 16 December 2016 (has links)
Cette thèse propose une méthodologie pour caractériser et intégrer les distributions minéralogiques des dépôts de l’Eocène Inférieur du Bassin de Graus-Tremp-Ainsa dans un cadre séquentiel reconstruit à haute résolution. Le couplage des approches stratigraphiques et géochimiques/minéralogiques permet d’évaluer la part des forçages tectoniques, climatiques, eustatiques et diagénétiques sur l’enregistrement sédimentaire et minéralogique du bassin. La caractérisation de la minéralogie repose sur un calcul automatisé utilisant la géochimie multi-élémentaire et calibré ponctuellement par les outils d’analyse minéralogique conventionnels (pétrographie, DRX, Qemscan, microsonde). Elle a l’avantage de permettre de traiter les évolutions minéralogiques à l’échelle du bassin et sur l’ensemble des lithologies rencontrées. Après avoir évalué les effets de la diagenèse, du tri hydrodynamique et reconstitué la composition minéralogique primaire des sédiments, nous caractérisons les différentes sources.Nous précisons l’évolution de la tectonique (avec un pas de temps de l’ordre du million d’années) et ses effets sur l’architecture sédimentaire et la minéralogie des dépôts. Ceux-ci montrent un contrôle spatial de la diagenèse et des changements spatio-temporels des sources, liés à une compétition entre la tectonique intrabassinale (activité des chevauchements locaux) et régionale (surrection de l’orogène et subsidence flexurale). Nous montrons également que l’impact de la tectonique est modulé par des anomalies climatiques ponctuelles de l’ordre de la centaine de milliers d’années (PETM, ELMO, X-Event), que nous avons reconnues par un changement marqué des environnements de dépôt et des cortèges argileux.Deux grands épisodes régionaux caractérisent l’évolution du Bassin piggyback de Graus-Tremp-Ainsa. Le stade précoce, d’âge Ilerdien-Cuisien Inférieur, est marqué par le passage d’une rampe carbonatée mixte à des systèmes deltaïques alimentés depuis l’orogène pyrénéen par des contributions plutoniques. Cet ensemble passe ensuite à un vaste système fluvio-deltaïque au Cuisien Inférieur / Moyen, montrant l’apport de lithiques carbonatés et silicoclastiques qui coïncide avec l’émergence des nappes sédimentaires. La fin de cet épisode est marquée par la propagation du chevauchement du Montsec et de ses rampes latérales, provoquant un partitionnement du bassin, induisant la surrection du Bassin de Graus-Tremp et une forte subsidence du Bassin d’Ainsa. Ce contraste de subsidence est souligné par un partitionnement de la diagenèse, avec une kaolinisation des formations supérieures du Bassin de Graus-Tremp, liée à la percolation d’eaux météoriques, et, dans le Bassin d’Ainsa, une albitisation des grès couplée à une illitisation des smectites dans les lutites, liée à une diagenèse d’enfouissement plus marquée. / We develop here a methodology to integrate the mineralogical record into a high resolution sequence stratigraphic framework realized in the Early Eocene Graus-Tremp-Ainsa Basin. Coupling stratigraphic with geochemical and mineralogical approaches allows us to unravel the effects of tectonics, climate, eustasy and diagenesis on basin architecture and mineralogy. An automated computed mineralogy is derived from whole-rock geochemical data, and calibrated against direct mineral quantifications (petrography, DRX, Qemscan, microprobe). It provides a basinscale view of mineral distribution, irrespective of the lithology. Diagenetic overprint and hydrodynamic sorting effects are evaluated first, then primary mineral distributions are reconstructed and ascribed to different types of sediment sources.We show that, at the million-year timescale, tectonics shape the architecture and the mineralogy of the deposits. Spatially distributed diagenesis and temporal and spatial changes in sediment sources reflect the competing effects of intrabasinal tectonics (local thrust displacements) versus basinscale flexural subsidence linked to the orogen uplift and loading. Tectonically-driven changes are also sensitive to higher frequency (100 ky) anomalic climatic events (PETM, ELMO, X-EVENT) leaving a mineralogical signal in clay fractions and environment deposits succession.The basinscale evolution displays two contrasting stages. During the Ilerdian to the lower Cuisian, a mixed carbonate ramp evolves to a set of deltaic fans of Northern (Pyrenean orogen) provenance delivering plutonic-dominated materials. Then, during the lower/mid Cuisian, they are overprinted by a large fluvial and deltaic system bringing recycled carbonates and siliciclastics sourced in the emerging eastern to southern sedimentary thrust sheets. Later on, the propagation of the Montsec thrust and its lateral ramp decouples the uplifted Graus-Tremp basin from the strongly subsiding Ainsa basin. These different subsidizing schemes are underlined diagenetic overprints diverge, with an extensive kaolinisation of the uppermost units in the Graus-Tremp Basin driven by meteoric fluid circulations, and a severe albitisation of sandstones in the Ainsa basin, coupled with the illitisation of smectites in the lutites and caused by deep basinal fluids.
7

A Healthcare Failure Mode and Effect Analysis on the Safety of Secondary Infusions

Yue, Ying Kwan 27 November 2012 (has links)
Secondary infusions are a common and convenient method to administer intermittent infusions unattended through a single IV access using infusion pump technology. Previous studies have indicated that clinicians have a high frequency of committing operation errors while administering secondary infusions, which can cause patient harm. The purpose of this study was to evaluate the safety of secondary infusion practice by identifying and analyzing potential failure modes when delivering secondary infusions on five different smart infusion pumps. Healthcare Failure Mode and Effect Analysis (HFMEA) was used to prioritize potential failure modes that are considered high-risk for each pump. Results showed that four of the five pumps were not able to mitigate physical set-up errors. As well, each pump contributed differently to programming errors due to difference in interface design. Recommendations from this study focused on outlining desired infusion pump features and mitigation strategies to help alleviate high-risk secondary infusion failure modes.
8

A Healthcare Failure Mode and Effect Analysis on the Safety of Secondary Infusions

Yue, Ying Kwan 27 November 2012 (has links)
Secondary infusions are a common and convenient method to administer intermittent infusions unattended through a single IV access using infusion pump technology. Previous studies have indicated that clinicians have a high frequency of committing operation errors while administering secondary infusions, which can cause patient harm. The purpose of this study was to evaluate the safety of secondary infusion practice by identifying and analyzing potential failure modes when delivering secondary infusions on five different smart infusion pumps. Healthcare Failure Mode and Effect Analysis (HFMEA) was used to prioritize potential failure modes that are considered high-risk for each pump. Results showed that four of the five pumps were not able to mitigate physical set-up errors. As well, each pump contributed differently to programming errors due to difference in interface design. Recommendations from this study focused on outlining desired infusion pump features and mitigation strategies to help alleviate high-risk secondary infusion failure modes.
9

Architecture of deposits formed in a tectonically generated tidal strait, upper Baronia Fm., Ager Basin, South Central Pyrenees, Spain

Bens, Ashley Elizabeth 15 July 2011 (has links)
The upper Baronia Fm. of the Ager Basin, Spain, is composed of a hierarchy of prominently stacked sets of primarily unidirectional cross-strata in units up to 40m thick. These large sets of cross-strata are interpreted as deposits of migrating subaqueous tidal simple dunes, compound dunes, and compound dune complexes within an approximately 10km wide north-east to south-west oriented seaway with water depths of a calculated 60-90m. These interpretations are opposed to prior interpretations of the upper Baronia Fm. which suggests deposits were formed by tidal bars within a deltaic environment (Mutti et al., 1985). Dunes developed due to dominantly north-east directed tidal currents driven through the strait by tidal phase differences between the two bodies of water (Mediterranean and Atlantic basins) connected by the seaway. Evidence for syn-tectonic deposition further constrains timing of movement of the northern basin bounding Montsec thrust to the early Eocene. Indicators for movement on the Montsec thrust include the development of the Ager Basin elongate to the thrust front, and syn-tectonic signals in the fill of the basin such as local conglomerate wedges and emplacement of olistoliths. Individual cross-stratified successions are interpreted to have formed with variable flow velocity and orientation, resulting in a basin wide stacking of compound dune complexes. These compound dune complexes form cross stratified successions which are distributed throughout the basin according to the variable current speeds, dune size which impacts migration, and sediment availability during deposition. This results in the observed distributions of muddy and sandy sediments, where finer grained materials accumulate preferentially in the low energy troughs of the hierarchy of compound dunes. / text
10

Contribuições ao modelo de manutenção preventiva “PIGGYBACK” pela abordagem multicritério e de gestão de sobressalentes

RODRIGUEZ, Túlio Fidel Orrego 29 February 2016 (has links)
Submitted by Isaac Francisco de Souza Dias (isaac.souzadias@ufpe.br) on 2016-07-05T18:15:55Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação - Tulio Orrego - Ficha catalografica.pdf: 1800798 bytes, checksum: 9949d1db150744a49de034ac385fec55 (MD5) / Made available in DSpace on 2016-07-05T18:15:55Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação - Tulio Orrego - Ficha catalografica.pdf: 1800798 bytes, checksum: 9949d1db150744a49de034ac385fec55 (MD5) Previous issue date: 2016-03-16 / CAPES / A competitividade causada pela globalização é um dos fatores mais importantes que impactam as organizações prestadoras de serviços e às empresas produtoras. É por isso que é mais frequente focar os seus esforços no melhoramento de estratégias de manutenção, mais especificamente em aquelas operações que possuem um grande impacto no nível de serviço e de produção, como é o caso de manter a confiabilidade do sistema em níveis que assegurem a produtividade. Para garantir que a área de manutenção seja eficaz, deve-se estudar qual política de manutenção é mais apropriada definindo qual, ou quais, modelo é o mais eficiente. A decisão de estabelecer o modelo de manutenção representa uma das decisões mais importantes dentro desse contexto, devido a que esta atividade compreende uma taxa importante dos custos operacionais e envolve grande quantidade dos recursos atribuídos aos trabalhos dentro da unidade produtiva. Nesta pesquisa tem-se grande interesse em estudar o comportamento particular da política de manutenção preventiva chamada de Piggyback desenvolvida por Tom Y. Liang no ano de 1985, a qual até hoje não conta com indícios de ter sido novamente explorada. Esta política gera grande curiosidade por possuir uma metodologia de manutenção simples e de fácil aplicabilidade para ser utilizada em unidades de produção, além de não precisar de grande investimento para pô-la em prática. A primeira parte desta pesquisa foi desenvolvida com base nos resultados apresentados por Liang (1985) referidos ao custo de serviço (CS) e às manutenções não programadas (UM por sua sigla em inglês) ao usar o modelo 1 da política Piggyback. Nesse modelo, o sistema é composto por dois equipamentos A e B, cujos tempos de falha estão configurados em série e seguem distribuições de probabilidade Exponencial e Weibull, respectivamente. Assim, o objetivo deste estudo é a definição do intervalo de manutenção preventiva (T) que proporcione a maior utilidade global de acordo às preferências de um decisor, utilizando a Teoria da Utilidade Multiatributo (MAUT por sua sigla em inglês) como método de decisão. Por último, é apresentada a integração do modelo de manutenção preventiva Piggyback com o modelo de gestão de sobressalentes, particularmente definido como revisão contínua. A ligação entre estes modelos é baseada nos tempos de falha dos equipamentos, os quais são gerados aleatoriamente seguindo uma distribuição de probabilidade e no intervalo (T), e são avaliados com os possíveis casos pré-estabelecidos para cada um dos modelos; portanto este procedimento é marcado pela simulação de N sistemas. A importância da integração da manutenção com a gestão de sobressalentes é baseada principalmente em assegurar a disponibilidade da unidade produtiva com o menor custo global de serviço. Para fazer isso, as variáveis de decisão devem ser estabelecidas visando o ganho geral por acima dos ganhos individuais, o que se consegue otimizando as variáveis de forma simultânea. Desse modo, a integração dos modelos pode ser útil para o melhoramento da disponibilidade de unidades produtivas agregando valor à tomada de decisão mediante a inclusão de todos os objetivos relevantes no julgamento. / The competitiveness caused by globalization is one of the most important factors that impact the service organizations and manufacturing companies. Therefore enterprises usually focus their efforts on improving maintenance strategies, particularly in those operations which have a major impact on the level of service and production, as the case of maintaining system reliability levels that ensures productivity. In order to confirm that the maintenance area to be effective, one have to consider which maintenance policy is more appropriate, defining which model, or models, is most efficient. The decision about establishing the maintenance model is one of the most important decisions in this context, because this activity contains an important rate of operating costs and it involves large amount of resources allocated to work within the productive unit. This research has great interest in studying the particular behavior of preventive maintenance policy called Piggyback developed by Tom Y. Liang in 1985, which nowadays does not have evidence of being explored again. This policy creates great curiosity because it has a simple maintenance methodology and it is easily applicable for use in factories, besides it not needs big investment to put it into practice. The first part of this research was developed based on the results presented by Liang (1985) referred to the Service Cost (SC) and unscheduled maintenance (UM) when the model 1 of Piggyback policy is used. In that model the system contains two pieces of equipment A and B whose failure times are configured in séries and have exponential and Weibull probability distributions respectively. Thus, the aim of this study is the definition of preventive maintenance interval (T) that provides the most global utility according to decision maker preferences and using the Multi-Attribute Utility Theroy (MAUT) as a decision-making method. Finally, it shows the integration of preventive maintenance model Piggyback with the model of spare management, particularly set as contínuous review. The connection between these models is based on the equipment failure times, which are randomly generated by a probability distribution and the interval (T), and are evaluated with possible pre-established cases for each model, so this procedure is marked by simulation of N systems. The importance of integrating maintenance with spare management is based primarily on ensuring the availability of the plant with the lowest overall cost of service. To do this, the decision variables should be established in order to put the overall gain on top of individual earnings, which is achieved by simultaneously optimizing the variables. Thereby the integration of the models may be useful for improving the availability of facilities adding value to decision-making process by including all relevant goals of the process.

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