271 |
Characteristics associated with unplanned extubation in an intensive care unit Nairobi, KenyaAhamed, Parin Hanif 11 1900 (has links)
Unplanned extubation is premature removal of endotracheal tube, is an adverse event; which can either, be accidental during a nursing procedure or self deliberate by the patient. The AACN Synergy Model for Patient Care was used as conceptual model for this study. A retrospective descriptive design revealed that over a period of two years, 327 patients admitted to the intensive care unit require intubation of which 40.4% were self-deliberate extubation and 59.4% accidental extubation. Of the accidental extubated patients, 29.8% had physical restrains, 57.6% received sedation, 43.9% had analgesic infusion and 38.9% were on neuromuscular blockade. A means Glasco Coma Scale was 9.4 and 56% of the patients were reported as being. Most patients (89.9%) required re-intubation. The findings also revealed that 49.1% of the nurses who cared for the patients when the extubation occured had one patient at the time. Also, 84.2% of nurses had 0-6 years of nursing experience and 74% of nurses had less than five years of ICU experience. / Health Studies / M.A. (Health Studies)
|
272 |
A collaborative approach towards enhancing synergy in a critical care unit in GautengDe Kock, Juliana 22 April 2014 (has links)
In today’s world healthcare all over the world is profoundly challenged by rapid
technological advancements, violence, terrorism, diverse cultures, proliferating chronic
diseases, and the worst nursing shortage. In addition to these complex and daunting
challenges healthcare continue to focus the attention on hospitals to review and modify
the way care is delivered to patients. As key role players and consistent members of the
multidisciplinary team critical care nurses are uniquely positioned to modify and review
the quality of patient care through synergy between the patients’ needs, the nurses’
competencies, and the critical care environment.
A collaborative approach towards enhancing synergy in a CCU was undertaken in a
CCU in a private hospital in Gauteng. The study was guided by the American
Association for Critical Care Nurses Synergy Model for Patient Care and conducted
within the critical social theory paradigm. The nature of the research was descriptive,
explorative and contextual and both qualitative and quantitative approaches were used.
Action research cycles were followed to assess existing synergy between the patients’
needs, the nurses’ competencies and the characteristics of the environment in the CCU.
An action plan was formulated and implemented towards enhancing synergy in the
CCU. The implemented plan was adjusted based on observations and reflections
following each of the five cycles of the project / Health Studies / D. Litt. et Phil. (Health Studies)
|
273 |
The didactics of an English-Bemba anthology of oral traditional narratives in the Zambian Grade Ten literature classMwelwa, Joseph Mulenga 06 1900 (has links)
Within the multilingual context of Zambia, Grade Ten Literature in English language pedagogy could incorporate the learners’ language and culture to help enrich participation and facilitate understanding of concepts among the learners who are in the foundational year of the literature course. However, current Literature in English language pedagogy is characterized by a monolingual practice with English dominating the literature learning/teaching classroom space – thus rendering the learners’ local linguistic and cultural knowledge impotent. To remedy the situation, the study investigated a dominant local language – Bemba – for a linguistic genre suitable for use in Literature in English language pedagogy. Archival retrieval and live recording of Bemba oral traditional narratives produced the initial research data. Transcription and translation techniques created an anthology from which a bilingual resource (BR) was derived. The BR was then trialled among Grade Ten Literature in English language learners in schools in the Copperbelt province of Zambia. Focus group discussions by participants generated evaluative data whose analysis using qualitative techniques indicate that learners responded positively to the bilingual materials and approach. Teachers were equally enthusiastic, describing the bilingual approach to Literature in English language pedagogy as unique, innovative and liberating. A Linguistic Synergy theory was thus developed to account for teachers’ and learners’ experiences in a bilingual Literature in English classroom. / English Studies / D. Litt. et Phil. (English)
|
274 |
Management's perception of customers' service feedback in an ICT company : an explorative studyFaasen, Zanne 11 1900 (has links)
The purpose of this research was to explore how management explains the difference between the overall service quality ratings of staff at Company X versus the overall service quality ratings of Company X. The organisation conducts customer service measurements on a regular basis to monitor their customers overall service experience regarding the staff and the organisation. The results of the research identified a discrepancy regarding customer perceptions of the service they receive from the staff versus the service Company X is providing. Management was the focus of the study due to management having a direct or indirect influence on service gaps in the organisation.
The SERVQUAL model, together with systems theory, was applied as a framework to explore management perceptions as to why a service quality gap exists. In-depth face-to-face interviews were conducted with management staff of Company X who are responsible for customer service. Thematic analysis was used to analyse the interviews and through content analysis six main themes were identified with various subthemes. The theoretical and empirical objectives were addressed and it was concluded that inconsistent practices within the organisation specifically the lack of consistent performance management can create an inconsistent service experience. The findings also revealed that Company X have various focus areas to improve the overall customer experience of the organisation. / Psychology / M.A. (Psychology (Research consultation))
|
275 |
Especificidade do apetite ao sódio: uma possível contribuição hormonal. / Sodium appetite specificity: a possible hormonal contribution.David, Richard Boarato 24 August 2006 (has links)
Made available in DSpace on 2016-06-02T19:22:47Z (GMT). No. of bitstreams: 1
DissRBD.pdf: 921826 bytes, checksum: 40bd9588528375b232a2fdf78d110ff9 (MD5)
Previous issue date: 2006-08-24 / The hypothesis of a synergy between two hormones responsible for sodium
conservation, aldosterone and angiotensin II (ANG II), explains the expression of a
characteristic of sodium appetite, hypertonic NaCl intake, in a hypovolemic animal.
Hypertonic NaCl intake can be induced in normovolemic rats that received a combined
treatment of mineralocorticoid and ANG II at individual doses not sufficient to induce sodium
intake (paradigmatic synergy test). Considering the motivation to specific sodium intake
another characteristic of sodium appetite, the objective of the present dissertation was to find
out a role for the interaction between mineralocorticoid and ANG II on the specificity of
sodium appetite.
Sprague-Dawley Holtzman rats (≅ 300 g b.w.) were housed with access to water and
one or more palatable (0.01 M KCl, 0.05 mM CaCl2, 0.15 M NaHCO3, 0.15 M NaCl) or
hypertonic (0.50 M NaCl) mineral solutions for ingestion. In two-bottle tests, a bottle
contained water and another bottle contained either 0.01 M KCl, 0.15 M NaHCO3, 0.15 M
NaCl or 0.50 M NaCl. In five-bottle tests, a bottle contained water and each one of the
remaining four bottles contained either 0.01 M KCl, 0.05 mM CaCl2, 0.15 M NaHCO3 or 0.15
M NaCl, respectively.
In sodium depletion tests, intact rats received each a 10 mg sc. injection of furosemide
or vehicle followed by 24 h access to sodium deficient food and water. Then, food was
removed and mineral solutions and water were offered for recording their intake (sodium
appetite test). In the paradigmatic synergy test, the animals received daily single sc injection
of 2.5 mg of deoxycorticosterone acetate (DOCA) or sunflower oil (vehicle) for three days
and a left lateral cerebroventricular injection of 50 ng of ANG II four hours after the last
DOCA or oil injection. Fluid intake record began immediately after ANG II injection and
food removal.
The daily intake record showed no preference for any solution or water when animals
had access to five bottles. Sodium depletion induced a preferential sodium intake, with higher
NaCl than NaHCO3 intake, in either two- or five-bottle sodium appetite tests. DOCA alone
enhanced the daily 0.15 M NaCl and NaHCO3 intake, but did not alter KCl or 0.50 M NaCl
intake in two-bottle tests. In the paradigmatic tests with normovolemic animals, ANG II
combined to oil induced the ingestion of all three palatable mineral solutions (KCl, NaHCO3,
NaCl) and water, in two-bottle tests, and preference for NaHCO3 in five-bottle tests. DOCA
pretreatment enhanced only sodium solution intake, particularly NaCl intake, induced by
ANG II in two-bottle tests (0.15 M NaCl: DOCA/ANG II = 24.5 ± 6.7 ml/120 min. vs.
OIL/ANG II = 9.2 ± 1.8 ml/120 min.; 0.15 M NaHCO3: DOCA/ANG II = 17.0 ± 1.8 ml/120
min. vs. OIL/ANG II = 14.6 ± 2.1 ml/120 min.; 0.01 M KCl: DOCA/ANG II = 9.8 ± 1.9
ml/120 min. vs. 11.9 ± 1.2 ml/120 min.), and enhanced by 80 % the total sodium solution
intake in the beginning of the five-bottle test. The combined effect of DOCA with ANG II on
the induction of 0.50 M NaCl intake in a two-bottle test was replicated in our animals.
The results from the paradigmatic synergy test are coherent with results from sodium
appetite tests, suggesting that the mineralocorticoid may turn the effect of ANG II on mineral
intake more selective to sodium intake. Thus, the combined ANG II and mineralocorticoid
action could contribute to the expression of two characteristics of sodium appetite, not only
the acceptance of hypertonic sodium solutions, but also the selective sodium intake. / A hipótese do sinergismo entre dois hormônios responsáveis pela conservação de
sódio, a aldosterona e a ANG II, explica uma característica do apetite ao sódio, a ingestão de
NaCl hipertônico em um animal hipovolêmico. Ingestão de NaCl hipertônico pode ser
induzida em ratos normovolêmicos que receberam um tratamento combinado de
mineralocorticóide e ANG II, em doses individuais insuficientes para induzir a ingestão de
sódio (teste paradigmático do sinergismo). Sendo a motivação para uma ingestão específica
de sódio uma outra característica do apetite ao sódio, o objetivo desta dissertação foi o de
procurar um papel para a interação entre mineralocorticóide e ANG II na especificidade do
apetite ao sódio.
Foram utilizados ratos Sprague-Dawley Holtzman (≅ 300 g p.c.) ambientados com
livre acesso a bebedouros com água e uma ou mais soluções minerais palatáveis (KCl 0,01 M,
CaCl2 0,05 mM, NaHCO3 0,15 M, NaCl 0,15 M) ou hipertônica (NaCl 0,50 M). Em testes de
dois bebedouros, um dos bebedouros continha água e o outro, solução de KCl 0,01 M,
NaHCO3 0,15 M, NaCl 0,15 M ou NaCl 0,50 M. Em testes de cinco bebedouros, um dos
bebedouros continha água e cada um dos demais uma solução de KCl 0,01 M, CaCl2 0,05
mM, NaHCO3 0,15 M ou NaCl 0,15 M.
Testes com dois ou cinco bebedouros foram empregados em animais depletados de
sódio e no teste paradigmático do sinergismo. Nos testes de depleção de sódio, os animais
receberam injeção sc de 10 mg de furosemida ou veículo, seguida de acesso a uma dieta
hipossódica e água por vinte e quatro horas. Em seguida, o alimento foi removido e foram
oferecidas soluções minerais para registro da ingestão das mesmas e de água (teste do apetite
ao sódio). No teste paradigmático do sinergismo, os animais receberam injeção sc de 2,5 mg
de acetato de desoxicorticosterona (DOCA) ou óleo de girassol (veículo) uma vez ao dia,
durante três dias, e uma injeção de 50 ng de ANG II (ou salina) no ventrículo lateral esquerdo,
quatro horas após a última injeção de DOCA ou óleo. Passou-se a registrar a ingestão de
líquidos imediatamente após a injeção de ANG II e remoção da ração. O registro da ingestão diária mostrou que não houve preferência por nenhuma solução
ou água durante o período de ambientação com cinco bebedouros. A depleção de sódio
induziu ingestão preferencial de sódio no teste do apetite ao sódio, sendo a ingestão de NaCl
0,15 M maior do que a de NaHCO3 tanto nos testes de dois como de cinco bebedouros. O
tratamento com apenas DOCA aumentou a ingestão diária de NaCl 0,15 M e de NaHCO3 sem
alterar a ingestão diária de KCl e de NaCl 0,50 M, em testes de dois bebedouros. No teste
paradigmático com ratos normovolêmicos, a ANG II combinada ao óleo promoveu ingestão
das três soluções minerais palatáveis (KCl, NaHCO3, NaCl) e de água em testes de dupla
escolha, e preferência ao NaHCO3 no teste com cinco bebedouros. O pré-tratamento com
DOCA potenciou o efeito da ANG II apenas sobre a ingestão das soluções sódicas, mais
evidente para NaCl, no teste com dois bebedouros (NaCl 0,15 M: DOCA/ANG II = 24,5 ± 6,7
ml/120 min. vs. ÓLEO/ANG II = 9,2 ± 1,8 ml/120 min.; NaHCO3 0,15 M: DOCA/ANG II =
17,0 ± 1,8 ml/120 min. vs. ÓLEO/ANG II = 14,6 ± 2,1 ml/120 min.; KCl 0,01 M:
DOCA/ANG II = 9,8 ± 1,9 ml/120 min. vs. 11,9 ± 1,2 ml/120 min.), além de aumentar em 80
% a ingestão total de soluções sódicas no início do teste com cinco bebedouros. O efeito da
indução de ingestão de NaCl 0,50 M pela combinação de DOCA com ANG II em testes de
dois bebedouros foi replicado nos nossos animais.
Os resultados do teste paradigmático do sinergismo são coerentes com os testes do
apetite ao sódio, sugerindo que o mineralocorticóide possa tornar mais seletivo o efeito da
ANG II sobre a ingestão mineral. Assim, uma interação entre ANG II e mineralocorticóide
poderia contribuir para a expressão de duas características do apetite ao sódio, não apenas a
aceitação de soluções hipertônicas de NaCl, mas também a ingestão seletiva de sódio.
|
276 |
Sustaining Sustainable Mobility : the Integration of Multimodal Public Transportation in Addis Ababa / Favoriser une mobilité durable : l’intégration du transport public multimodal à Addis AbebaHussen, Berhanu Woldetensae 27 May 2016 (has links)
Addis-Abeba, qui s’étend sur 540 km2 et compte 3,1 millions d’habitants, connait aujourd’hui des transformations socio-économiques et spatiales rapides. Elle n’est pas seulement le coeur politique, commercial, économique et financier du pays mais aussi une ville internationale accueillant le siège de l’Union africaine et d’autres institutions internationales. Comme d’autres villes africaines, elle connait un rythme élevé d’urbanisation. Ce processus a impliqué la croissance du nombre d’habitants mais aussi une extension spatiale accrue. En conséquence, la demande de déplacements et la longueur des parcours ont augmenté. Le transport joue ainsi un rôle clé, pesant sur le développement socio-économique et la configuration de l’espace urbain. Tout aussi important, en tant que demande dérivée, il joue sur la capacité des citadins à accomplir leurs diverses activités. La motorisation des ménages restant faible en dépit d’une lente progression, le transport public constitue le principal moyen d’accès à une mobilité motorisée pour la majorité de la population. L’offre est constituée d’une multitude d’opérateurs formels et informels, travaillant selon un schéma artisanal. On estime à plus de 18 000 les véhicules de transport public, la plupart de faible capacité, qui parcourent chaque jour les rues d’Addis-Abeba. En dépit de son importance, le transport public souffre de capacités d’investissement insuffisantes ainsi que, jusqu’à récemment, du manque d’une politique publique claire et affirmée. Il pâtit également de l’absence d’une approche intégrée, pour sa planification, sa gestion et sa mise en oeuvre. De nombreuses villes du Nord, parfois depuis près d’un demi-siècle, ont choisi de construire un service intégré de transport public. L’intégration y est vue comme un outil viable pour offrir un transport urbain de haute qualité et « sans couture », permettant un développement urbain durable. Par contre, les villes africaines, caractérisées par une urbanisation rapide, des taux d’équipement automobile faibles, un système de transport public déficient et des contraintes financières majeures manquent de telles expériences d’intégration du transport public. Notre question est donc : « Comment les villes africaines peuvent-elles reproduire et mettre en oeuvre des politiques d’intégration du transport public ? », originellement développées dans les villes du Nord. La thèse essaie d’apporter des éléments de réponse à cette question. Elle s’appuie sur une analyse des différentes formes d’intégration du transport public. Puis elle propose un schéma de conception et de mise en oeuvre d’un système de transport public intégré, appréhendé comme un outil de mobilité urbaine durable pour Addis-Abeba. / Addis Ababa, with an area of 540 km2 and with population of 3.1 million people is experiencing a rapid pace of socio-economic and physical transformation. The city is not only the political, commercial, economic and financial hub of the country but also an international city serving as the seat of the African Union and various international organizations. Alike many African Cities, Addis Ababa has been undergoing a high rate of urbanization. This process of rapid urbanization has resulted in the increase in the size of the population and the physical expansion of the city. As a consequence, travel demand and length of the trip are increasing. Transportation plays a key role in determining the socioeconomic development and shaping the spatial development framework of the city. Equally important, transportation as derived demand is also a fundamental means for residents to fulfill their various activities. In Addis Ababa motorization, although on the increase, is low and public transportation is the most important mode of motorized mobility for the large majority of the city’s population. There are various formal and informal operators of the public transport mainly operating on individual basis. It is estimated that there are over 18,000 public transport vehicles that are daily running in Addis Ababa, most of them low capacity vehicles. Despite its importance, the public transport sector not only suffers from shortage, insufficient capital investment, and until recently lack of clear governmental policy and leadership but also from the absence of integrated approach to its operation, planning and management.Many cities in the North have embarked on integrating the provision of public transportation for nearly half a century now. In these cities, integration in public transportation has been recommended as a viable instrument for providing high quality and seamless urban transport and enhancing sustainable urban development. African cities which are characterized by their high urbanization rate, low level of private car ownership, deficient public transportation system and significant financial constraints lack public transportation integration experiences. The question is then ‘how do African cities replicate and implement public transport integration practices?’ that have been originally developed for the Cities of the North. The thesis attempts to answer this question and analyses the different forms of public transport integration. It then proposes a framework for implementing integrated public transport as a sustainable means of urban mobility in Addis Ababa.
|
277 |
Etude des propriétés immunostimulantes de composés pariétaux de levure sur les macrophages murins et évaluation dans des modèles infectieux / Immuno-modulatory effects of yeast cell wall compounds on murine macrophages and their stakes in bacterial infections of mammary glandWalachowski, Sarah 17 June 2016 (has links)
Les ß-glucanes (BG) sont les polysaccharides les plus abondants de la paroi de Saccharomyces cerevisiae. Depuis des millénaires, ils sont utilisés pour leurs propriétés immunostimulantes et leurs potentiels thérapeutiques. L'objectif de ce travail était de caractériser la réponse immunitaire induite par les BG et de comprendre leurs modes d'action sur les macrophages murins en contexte infectieux. Nous avons montré que (i) les extraits de paroi enrichis en BG n'induisent qu'une faible production de cytokines par les macrophages contrairement aux extraits bruts, (ii) la réponse inflammatoire médiée par les extraits bruts résulte de la signalisation des TLRs et non de Dectin-1 et (iii) les BG stimulent la synthèse tardive de GM-CSF via Dectin-1. En conditions infectieuses, les BG enrichis confèrent une forte signature inflammatoire aux macrophages prétraités conduisant à l'amplification de la production cytokinique, à la synthèse de ROS et l'optimisation de la clairance bactérienne. En conclusion, cette étude souligne les enjeux de l'utilisation des BG enrichis comme adjuvants dans l'amélioration de la résistance des individus aux infections. / ß-glucans (BG) are the most abundant polysaccharides of the Saccharomyces cerevisiae cell wall. For decades, they have been extensively used because of their immuno-modulatory properties and their potential therapeutic effects. The aim of this study was to characterize the immune response induced by BG and to understand their mechanisms of action on murine macrophages occurring upon bacterial infections. We demonstrated that (i) BG-enriched extracts trigger low amounts of cytokine production in contrast with crude products, (ii) the immune response mediated by crude extracts results from TLRs and not from Dectin-1 signaling and (iii) BG-enriched compounds stimulate the late and strong induction of GM-CSF in a Dectin-1-dependent manner. Upon bacteria exposure, BG-enriched extracts confer a strong inflammatory to pretreated macrophages leading to synergistic increase of cytokine release, ROS production and better clearance of pathogens. Altogether, our findings emphasize the relevancy of using BG-enriched extracts for the design of novel adjuvant formulations contributing to individuals' resistance to infections.
|
278 |
Biceps brachii synergy and its contribution to target reaching tasks within a virtual cubeHe, Liang 07 1900 (has links)
Ces dernières années, des travaux importants ont été observés dans le développement du contrôle prothétique afin d'aider les personnes amputées du membre supérieur à améliorer leur qualité de vie au quotidien. Certaines prothèses myoélectriques modernes des membres supérieurs disponibles dans le commerce ont de nombreux degrés de liberté et nécessitent de nombreux signaux de contrôle pour réaliser plusieurs tâches fréquemment utilisées dans la vie quotidienne. Pour obtenir plusieurs signaux de contrôle, de nombreux muscles sont requis mais pour les personnes ayant subi une amputation du membre supérieur, le nombre de muscles disponibles est plus ou moins réduit selon le niveau de l’amputation. Pour accroître le nombre de signaux de contrôle, nous nous sommes intéressés au biceps brachial, vu qu’anatomiquement il est formé de 2 chefs et que de la présence de compartiments a été observée sur sa face interne. Physiologiquement, il a été trouvé que les unités motrices du biceps sont activées à différents endroits du muscle lors de la production de diverses tâches fonctionnelles. De plus, il semblerait que le système nerveux central puisse se servir de la synergie musculaire pour arriver à facilement produire plusieurs mouvements. Dans un premier temps on a donc identifié que la synergie musculaire était présente chez le biceps de sujets normaux et on a montré que les caractéristiques de cette synergie permettaient d’identifier la posture statique de la main lorsque les signaux du biceps avaient été enregistrés. Dans un deuxième temps, on a réussi à démontrer qu’il était possible, dans un cube présenté sur écran, à contrôler la position d’une sphère en vue d’atteindre diverses cibles en utilisant la synergie musculaire du biceps. Les techniques de classification utilisées pourraient servir à faciliter le contrôle des prothèses myoélectriques. / In recent years, important work has been done in the development of prosthetic control to help upper limb amputees improve their quality of life on a daily basis. Some modern commercially available upper limb myoelectric prostheses have many degrees of freedom and require many control signals to perform several tasks commonly used in everyday life. To obtain several control signals, many muscles are required, but for people with upper limb amputation, the number of muscles available is more or less reduced, depending on the level of amputation. To increase the number of control signals, we were interested in the biceps brachii, since it is anatomically composed of 2 heads and the presence of compartments was observed on its internal face. Physiologically, it has been found that the motor units of the biceps are activated at different places of the muscle during production of various functional tasks. In addition, it appears that the central nervous system can use muscle synergy to easily produce multiple movements. In this research, muscle synergy was first identified to be present in the biceps of normal subjects, and it was shown that the characteristics of this synergy allowed the identification of static posture of the hand when the biceps signals had been recorded. In a second investigation, we demonstrated that it was possible in a virtual cube presented on a screen to control online the position of a sphere to reach various targets by using muscle synergy of the biceps. Classification techniques have been used to improve the classification of muscular synergy features, and these classification techniques can be integrated with control algorithm that produces dynamic movement of myoelectric prostheses to facilitate the training of prosthetic control.
|
279 |
Modellierung und Simulation der Vergasung von BrennstoffmischungenGärtner, Lars-Erik 02 October 2015 (has links)
Mit Hilfe eines variabel einsetzbaren Reaktornetzwerkmodells (RNM) wird in der vorliegenden Dissertation der Prozess der Vergasung von Brennstoffmischungen in der Fließbildsimulation beschrieben. Neben der Untersuchung von gestuften Prozessketten zur Veredelung von kohlenstoffhaltigen Energieträgern ist damit auch die differenzierte Analyse von Effekten während der Vergasung von binären und ternären Brennstoffmischungen möglich. Die Erstellung sowie Validierung des RNM wird anhand des PEFR-Vergasers, des SFGT-Vergasers und des Hybridwandvergaser vorgenommen. Die anschließende Analyse der Vergasung von Brennstoffmischungen zeigt, dass in ihren Eigenschaften sehr heterogene Brenn¬stoffmischungen Synergieeffekte bei der Vergasung hervorrufen. Diese sind in der Literatur schon oft beschrieben worden, eine systematische Analyse wird jedoch erst in der vorliegenden Dissertation durchgeführt.:Nomenklatur XIV
1 Einleitung 1
2 Grundlagen 3
2.1 VERGASUNG 3
2.1.1 Vergasungsreaktionen 3
2.1.2 Vergasungskennzahlen 4
2.1.3 Modellierung der Vergasung 6
2.2 CO-VERGASUNG 8
2.2.1 Brennstoffe 8
2.2.2 Großtechnische Anwendung 8
2.2.3 Experimentelle Arbeiten 10
2.2.4 Modellierung und Simulation 13
2.2.5 Synergieeffekte 13
2.3 STOFFGEFÜHRTE PROZESSKETTE 15
2.4 BRENNSTOFFAUSWAHL UND BRENNSTOFFEIGENSCHAFTEN 16
2.5 ABLEITUNG DER AUFGABENSTELLUNG UND METHODIK 19
3 Entwicklung des Reaktornetzwerkmodells 22
3.1 MODELLIERUNGSUMGEBUNG 23
3.2 THERMODYNAMISCHE ZUSTANDSGLEICHUNG 23
3.3 STOFFDATENBANK 24
3.4 STRÖMUNGSBEDINGUNGEN IM FLUGSTROMREAKTOR 25
3.4.1 Zonenmodell 25
3.4.2 Verweilzeitverhalten 29
3.5 PARTIKELMODELL 31
3.6 MODELLIERUNG DER REAKTORZONEN 35
3.6.1 Nahbrennerzone (Zone I) 35
3.6.2 Jetzone (Zone II) 36
3.6.3 Rezirkulationszone (Zone III) 41
3.6.4 Auslaufzone (Zone IV) 41
3.6.5 Wasserquench (Zone V) 41
3.7 REGELMECHANISMEN 42
3.7.1 Regelung der Aschefließtemperatur 42
3.7.2 Regelung des Kohlenstoffumsatzgrades 46
3.7.3 Regelung der maximalen Reaktoraustrittstemperatur 47
3.7.4 Kombinierte Regelung 47
3.8 LÖSUNGSALGORITHMEN UND KONVERGENZVERHALTEN 48
4 Validierung des Reaktornetzwerkmodells 51
4.1 REAKTORNETZWERKMODELL PEFR-VERGASER 51
4.1.1 Aufbau des PEFR-RNM 51
4.1.2 Validierung des PEFR-RNM 54
4.2 REAKTORNETZWERKMODELL SFGT-VERGASER 61
4.2.1 Aufbau des SFGT-RNM 61
4.2.2 Validierung des SFGT-RNM 62
4.3 REAKTORNETZWERKMODELL HYBRIDWANDVERGASER 74
4.3.1 Beschreibung der Technologie Hybridwandvergaser 74
4.3.2 Aufbau des Hybridwandvergaser-RNM 75
4.3.3 Validierung des Hybridwandvergaser-RNM 78
5 RNM-Analyse der Vergasung von Brennstoffmischungen 85
5.1 VORÜBERLEGUNGEN 85
5.1.1 Festlegung der Randbedingungen 85
5.1.2 Thermische Vergaserleistung 86
5.1.3 Simulationsdauer und Automatisierung 87
5.2 AUSWERTUNG DER RNM-ANALYSE VON BRENNSTOFFMISCHUNGEN 89
5.2.1 RNM-Analyse BSM-BRP (binär) im SFGT-Vergaser 89
5.2.2 RNM-Analyse BSM-BRP (ternär) im SFGT-Vergaser 95
5.2.3 RNM-Analyse BSM-ibi (binär) im SFGT-Vergaser 100
5.2.4 RNM-Analyse BSM-ibi (ternär) im SFGT-Vergaser 102
5.3 DISKUSSION DER ERGEBNISSE AUS RNM-ANALYSE 106
5.4 BSM-DIAGRAMME FÜR VERGASERBETRIEB 109
5.4.1 BSM-Diagramme für SFGT-Vergaser 109
5.4.2 BSM-Diagramme für Hybridwandvergaser 112
6 Zusammenfassung und Ausblick 117
Literatur 121
Abbildungsverzeichnis 133
Tabellenverzeichnis 141
Anhang 145 / Within this document the modeling and simulation of fuel blend gasification is investigated based on a variably applicable Reduced Order Model (ROM) developed for the flowsheet simulation of entrained-flow gasification reactors and processes. On one hand this enables the investigation of cascaded solid fuel conversion technologies and on the other hand effects during gasification of binary and ternary fuel blends are describable. The development as well as the validation of the ROM has been carried out for the SFGT gasifier, the PEFR gasifier and the hybrid-wall gasifier. The subsequent analysis of binary and ternary fuel blend gasification shows that fuel blends with very heterogeneous component properties induce synergy effects which have been reported in various peer review publications.:Nomenklatur XIV
1 Einleitung 1
2 Grundlagen 3
2.1 VERGASUNG 3
2.1.1 Vergasungsreaktionen 3
2.1.2 Vergasungskennzahlen 4
2.1.3 Modellierung der Vergasung 6
2.2 CO-VERGASUNG 8
2.2.1 Brennstoffe 8
2.2.2 Großtechnische Anwendung 8
2.2.3 Experimentelle Arbeiten 10
2.2.4 Modellierung und Simulation 13
2.2.5 Synergieeffekte 13
2.3 STOFFGEFÜHRTE PROZESSKETTE 15
2.4 BRENNSTOFFAUSWAHL UND BRENNSTOFFEIGENSCHAFTEN 16
2.5 ABLEITUNG DER AUFGABENSTELLUNG UND METHODIK 19
3 Entwicklung des Reaktornetzwerkmodells 22
3.1 MODELLIERUNGSUMGEBUNG 23
3.2 THERMODYNAMISCHE ZUSTANDSGLEICHUNG 23
3.3 STOFFDATENBANK 24
3.4 STRÖMUNGSBEDINGUNGEN IM FLUGSTROMREAKTOR 25
3.4.1 Zonenmodell 25
3.4.2 Verweilzeitverhalten 29
3.5 PARTIKELMODELL 31
3.6 MODELLIERUNG DER REAKTORZONEN 35
3.6.1 Nahbrennerzone (Zone I) 35
3.6.2 Jetzone (Zone II) 36
3.6.3 Rezirkulationszone (Zone III) 41
3.6.4 Auslaufzone (Zone IV) 41
3.6.5 Wasserquench (Zone V) 41
3.7 REGELMECHANISMEN 42
3.7.1 Regelung der Aschefließtemperatur 42
3.7.2 Regelung des Kohlenstoffumsatzgrades 46
3.7.3 Regelung der maximalen Reaktoraustrittstemperatur 47
3.7.4 Kombinierte Regelung 47
3.8 LÖSUNGSALGORITHMEN UND KONVERGENZVERHALTEN 48
4 Validierung des Reaktornetzwerkmodells 51
4.1 REAKTORNETZWERKMODELL PEFR-VERGASER 51
4.1.1 Aufbau des PEFR-RNM 51
4.1.2 Validierung des PEFR-RNM 54
4.2 REAKTORNETZWERKMODELL SFGT-VERGASER 61
4.2.1 Aufbau des SFGT-RNM 61
4.2.2 Validierung des SFGT-RNM 62
4.3 REAKTORNETZWERKMODELL HYBRIDWANDVERGASER 74
4.3.1 Beschreibung der Technologie Hybridwandvergaser 74
4.3.2 Aufbau des Hybridwandvergaser-RNM 75
4.3.3 Validierung des Hybridwandvergaser-RNM 78
5 RNM-Analyse der Vergasung von Brennstoffmischungen 85
5.1 VORÜBERLEGUNGEN 85
5.1.1 Festlegung der Randbedingungen 85
5.1.2 Thermische Vergaserleistung 86
5.1.3 Simulationsdauer und Automatisierung 87
5.2 AUSWERTUNG DER RNM-ANALYSE VON BRENNSTOFFMISCHUNGEN 89
5.2.1 RNM-Analyse BSM-BRP (binär) im SFGT-Vergaser 89
5.2.2 RNM-Analyse BSM-BRP (ternär) im SFGT-Vergaser 95
5.2.3 RNM-Analyse BSM-ibi (binär) im SFGT-Vergaser 100
5.2.4 RNM-Analyse BSM-ibi (ternär) im SFGT-Vergaser 102
5.3 DISKUSSION DER ERGEBNISSE AUS RNM-ANALYSE 106
5.4 BSM-DIAGRAMME FÜR VERGASERBETRIEB 109
5.4.1 BSM-Diagramme für SFGT-Vergaser 109
5.4.2 BSM-Diagramme für Hybridwandvergaser 112
6 Zusammenfassung und Ausblick 117
Literatur 121
Abbildungsverzeichnis 133
Tabellenverzeichnis 141
Anhang 145
|
280 |
Tre-stegsmetod för att kvantifiera komplexitet för IT-förslagAl-Qaysi, Ibrahim, Ghidei, Yonas January 2016 (has links)
Moderna företag är under ständig förändring. Företagen behöver således förändra, bygga ut och modifiera de applikationer som stödjer verksamheten. Att göra ändringar i arkitekturer på stora IT-system är inte heltbekymmerfritt. Det är ofta väldigt dyrt och tidskrävande. Problemet är att det inte finns några enkla metoder för att kvantifiera komplexitet på IT-förslag i tidigt skede av en implementation. Många verksamheter har således behov avatt kvantifiera komplexiteten på IT-förslag i deras beslutsprocess för att avgöra vilka system som är dyra och tidskrävande att implementera. Ett av dem är Sveriges militära försvarsorganisation, Försvarsmakten. Syftet förstudien blir sålunda att presentera en metod för att kvantifiera komplexitet och optimera implementation för IT-förslag. Målet för studien är därmed att presentera en modell som gör det möjligt för verksamheter att identifiera komplexa förslag som kan medföra onödiga projektrisker. Denna studie använder sig utav en kombination av kvalitativ och kvantitativ forskningsmetod med en induktiv forskningsansats. Studien evaluerar vilka olika sätt Försvarsmaktens mobilapplikation, FMTK kan implementeras på och vilken av implementationerna som är mest optimal beträffande komplexitet. Därefter presenteras resultatet för studien, Tre-stegsmetoden som inkorporerar den bästa implementationen. Slutligen drar studien slutsatsen, med hjälp av analyser och utvärderingar, att Tre-stegsmetoden är överlägsen andra metoder. / Modern enterprises are under constant change. Therefore, enterprises need to change, extend and modify the applications that support their businesses. Making changes in the architectures of large IT-systems however, are not straightforward. It is often very costly and time consuming. The problem is that there are no easy methods to quantify complexity and optimize an implementation in early phases of an application construction. Thus, many companies are in need of a method to quanitfy complexity of their IT-businessproposals in order to facilitate their decision-making process. One of them is the Swedish Armed Forces (sv. Försvarsmakten). The purpose of this study is therefore to present a simple method to quantify complexity and optimize implementation for IT-proposals. The purpose aligns with the goal, which is to present a model, which forms the basis for IT-proposals, for companies to consider in their process. This study uses a combination of a qualitative and quantitative research with an inductive research approach. Furthermore, this study evaluates in which ways Swedish Armed Forces application FMTK can be implemented and which implementations that are most optimal in terms of complexity. A method which incorporates the implementation is thereafter presented as a result of the study. Conclusively, the study shows with the help of analyses and evaluations that the presented method, namely the Three-stepmethod is superior to other methods.
|
Page generated in 0.032 seconds