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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.
211

La suspension du contrat en cas d’obstacle à l’exécution : en droit comparé français chinois / Suspension of contract in case of obstacle to the execution : In Sino-French comparative law

Yang, Liu 18 December 2013 (has links)
En pratique, de nombreux obstacles peuvent empêcher le déroulement naturel du contrat. Lorsque ces obstacles n'ont qu'un caractère provisoire, le droit contemporain offre au contractant une solution temporaire : la suspension du contrat. Cependant, jusqu'à nos jours, cette solution du droit n'est pas soumise à un régime juridique unitaire. La suspension se dissimule dans diverses techniques juridiques, traditionnelles ou modernes. Le droit comparé français chinois à l'égard de la suspension permet d'identifier clairement l'ensemble de ces techniques, d'en envisager une nouvelle compréhension et de proposer une systématisation du phénomène complexe de suspension. Notre étude a révélé plusieurs constatations importantes. Pour un contractant, la suspension n'est pas uniquement une solution permettant de sanctionner l'inexécution temporaire de son cocontractant, elle peut également servir à justifier son inexécution légitime. En outre, la suspension peut être utilisée non seulement en cas d'inexécution du contrat, mais aussi en cas de risque d'inexécution. Enfin, l'objet visé par la suspension peut être non seulement la prestation contractuelle, mais aussi les travaux préparatoires à celle-ci. / In practice several obstacles may prevent the natural progress of the contract. When those obstacles are not permanent in nature, modern law offers the contracting party a temporary solution : suspension of the contract. However, up until now, that legal solution has not been subject to a unitary legal system. Suspension is concealed by a range of traditional and modern legal techniques. Sino-French comparative law in relation to suspension makes it possible to clearly identify all these techniques, to envisage a new understanding and to offer a systematization of the complex phenomenon of suspension. Our study has revealed several important findings. For a contracting party, suspension is not merely a way to enable the sanctioning of temporary breach by the other contracting party; it can also be used to prove his legitimate breach. In addition, suspension can be used, not only in the event of breach of contract, but also in the event of the risk of breach. Lastly, the object affected by the suspension may not only be the contractual arrangement, but also the work leading up to it.
212

Kultury léčivých rostlin in vitro - XX / In vitro cultures of medicinal plants XX

Chreňová, Kateřina January 2016 (has links)
The study is aimed to enhance in vitro production of secondary metabolites in Genista tinctoria L. via elicitor treatment. The different levels of elicitor concentration - selenium dioxide were utilized to affect the quantity of isoflavonoids occurred in cultures. Experiment was perfomed in callus and suspension cultures on MS nutrient media supplemented with 10 g l-1 of NAA (α-naphtylacetic acid) as growth regulator. The elicitor was added in the form of solution in concentrations of 9,012.10-3 mol l-1 ; 9,012.10-4 mol l-1 and 9,012.10-5 mol l-1 . It was exposed for 6, 12, 24, 48, 72 and 168 hours. The content of isoflavonoids was determined by HPLC in dry weight (DW) and medium. The most effective production of genistin (6,20 mg. g-1 DW, 8,30 mg. g-1 DW) in callus culture was measured. It was reached in concentrations of 9,012.10-4 mol l-1 and 9,012.10-5 mol l-1 after 168 h elicitor treatment. The second most satisfactory genistin level 5,20 mg g-1 DW was detected after elicitor application in concentration of 9,012.10-4 mol l-1 after 6 h. The content of genistein, daidzein and formononetin in callus culture was low and in the most cases equal zero compared to control samples. The content of biochanin A was equal zero compared to control samples. The most efficient daidzein production (37,10 mg...
213

Kultury léčivých rostlin in vitro - IXX / In vitro cultures of medicinal plants IXX

Seidlová, Markéta January 2016 (has links)
In vitro cultures of medicinal plants - IXX The subject of this thesis is the evaluation of secondary metabolites production in in vitro cultures of Silybum marianum L. after elicitor treatment. In this study selenium dioxide as elicitor in concentrations of 9,012.10-3 mol/l; 9,012.10-4 mol/l; 9,012.10-5 mol/l was used. The samples were taken after 6, 12, 24, 48, 72 and 168 hours of elicitor treatment. The effect of elicitor was compared with control samples, which were cultured without elicitation. The content of taxifolin and flavonolignans was determined by the method of HPLC. The results showed, that almost all observed metabolites were released into a nutrient medium. Cells of callus and suspension cultures produced only small amounts of taxifolin (0.01 mg/g DW). Taxifolin and silymarin complex releasing into nutrient media was observed as in control and also in the elicitated samples of callus and suspension cultures. Selenium dioxide elicitation caused statistically significant increases in releasing taxifolin and silymarin complex into the nutrient medium. The statistically significant releasing of flavonolignans (2.2 mg/100 ml) to the medium of suspension culture was reached after 72 hours of treatment with selenium dioxide in concentration of c1 (9,012.10-3 mol/l). The statistically...
214

Analyse de l’influence des non-linéarités dans l’approche CRONE : application en isolation vibratoire

Serrier, Pascal 30 September 2008 (has links)
Cette thèse traite de la synthèse et de la réalisation d’un intégrateur d’ordre non entier borné en fréquence. La réalisation est faite par un réseau constitué d’un faible nombre de cellules capacitives et dissipatives. La première partie de ce mémoire s’attache à développer des méthodes permettant de déterminer les paramètres physiques des éléments du réseau à partir des quatre paramètres de haut niveau qui caractérisent l’intégrateur d’ordre non entier à réaliser. Les spécificités liées à une réalisation en technologie hydropneumatique sont détaillées. Il est montré, dans un contexte d’isolation vibratoire, qu’elles conduisent à des performances remarquables de robustesse du degré de stabilité et de robustesse de la rapidité vis-à-vis des variations de la masse suspendue, et ce, malgré l’existence de non-linéarités. Les non-linéarités sont étudiées à l’aide des séries de Volterra. La seconde partie est consacrée à l’application au secteur de l’automobile des résultats de la première partie. La synthèse et la réalisation d’une suspension CRONE hydractive, suspension multi-états dont le mode souple assure la robustesse du degré de stabilité de la caisse vis-à-vis des variations de la masse suspendue, sont proposées et validées en simulation sur un modèle de véhicule à 14 degrés de liberté. / The thesis deals with the synthesis and the realisation of a band limited fractional differentiator. The realisation is made thanks to a small number of resistive and capacitive cells (RC cells). The first part of this thesis is about some new methods to compute the physical parameters of the RC cells from the 4 high-level parameters of the band limited fractional differentiator. The specificities of a realisation using hydropneumatic technology are detailed. It is shown that, in vibration isolation, they lead to remarkable performances. The stability degree robustness and the rapidity robustness towards the variation of the sprung mass value are obtained in spite of non- linearities. Volterra serie expansion is used to study the non-linearities. The second part is about the application of the previous results to the automotive field. The design and the realisation of an hydractive CRONE suspension is proposed. An hydractive CRONE suspension is a suspension with several operating modes and which allows to obtain the stability degree robustness. The hydractive CRONE suspension is then test with a 14 degrees of freedom model of a car.
215

Modeling and Identification of Air Suspension in Heavy-Duty Vehicles

Lartén, Carl-Philip January 2016 (has links)
A heavy-duty vehicle can benefit from the height control of the chassis that anair suspension provides. For example, to retain a pitch angle parallel to the road,regardless of what load it carries. For the purpose of developing a controller,a model of the air suspension provides evaluation and testing opportunities aswell as it gives the option for more advanced model based controller algorithms.Furthermore, a model can provide with an accurate axle weight estimation. Inthis thesis, both physical and statistical models are developed and parametersare estimated by solving minimization problems. They are then evaluated usingdata collected from a Scania truck, comparing normalized mean-root error valuesas well as residual analysis of each model.
216

Rostlinné explantátové kultury jako potenciální zdroj fenylpropanoidů II. / Plant tissue cultures as a potential source of phenylpropanoids II.

Šandová, Kateřina January 2019 (has links)
1 ABSTRACT Charles University in Prague Faculty of pharmacy in Hradec Králové Department of pharmacognosy Student: Kateřina Šandová Supervisor: PharmDr. Marie Kašparová, PhD. Title of diploma thesis: Plant tissue cultures as a potential source of phenylpropanoids II. This diploma thesis deals with the monitoring of jasmonic acid biotic elicitation impact on the production of podophyllotoxin in Juniperus virginiana suspension culture. The monitoring was carried out in two varieties of J. virginiana: var. 'Glauca' (7th and 19th passage) and var. 'Hetzii' (7th passage). The elicitation of the suspension culture was performed in 4 jasmonic acid concentrations: 0.005 mmol/l, 0.05 mmol/l, 0.5 mmol/l, 5 mmol/l. Samples were taken after 6, 24, 48 and 168 hours of elicitation. The best podophyllotoxin production increase was observed in the suspension culture of Juniperus virginiana var. 'Glauca' (7th passage). To achieve this result, the concentration of elicitor was 5 mmol/l and elicitor was applied for 168 hours. The podophyllotoxin production percentage was 0.067% and production increased by 179% over the control. Keywords: Juniperus virginiana, suspension cultures, podophyllotoxin, elicitation
217

Ovlivnění produkce sekundárních látek deriváty pyrazinu v in vitro kulturách léčivých rostlin I. / The effect of pyrazine derivatives on the secondary metabolites production in in vitro cultures of medicinal plants I.

Dvořáková, Jana January 2019 (has links)
The aim of this work was to investigate the effect of pyrazine derivative, 1-octyl-3-(pyrazin-2- yl)urea, as an abiotic elicitor on the production of flavonoid rutin in in vitro cultures of Fagopyrum esculentum Moench., Cultivar Bamby. Suspension and callus cultures were cultivated on Murashige and Skoog nutrient medium (MS) with the addition of 2,4-dichlorophenoxyacetic acid (2,4-D) as growth regulator at a concentration of 1 mg/l. The elicitor solution was added to the cultures at three concentrations: c1 (100,0 mg/100 ml), c2 (10,0 mg/100 ml) and c3 (1,0 mg/100 ml). The elicitor was monitored at six time intervals: 6, 12, 24, 48, 72 and 168 hours. To control samples 1 ml of ethanol 96% was added instead of elicitor solution and samples were collected after 24 and 168 hours. Samples were taken at given time intervals and dried. Subsequently, the rutin content was monitored by HPLC. The rutin release into the nutrient medium was also tested. During the experiment on the callus cultures no statistically significant increase in rutin production after elicitor treatment was observed. But elicitor increased rutin production in suspension cultures after treatment in all tested concentrations. The calluses always released rutin into the nutrient medium. The rutin content in the media ranged from 53,4 to...
218

Digital konstruktion samt verifiering av hjulupphängning till JU Solar Team´s solbil 2019 / Digital construction and verification of wheel suspension for JU Solar Team´s solar car 2019

Svensson, Marcus, Gränsmark, Arvid January 2019 (has links)
There is a need to improve the JU Solar Team's new solar cell powered electric car's driving capabilities for the Bridgestone World Solar Challenge 2019. Partly to improve the car's safety and the ability to meet the competition requirements, but also to minimize effects that contribute to increased rolling resistance. The work is carried out at Jönköping Institute of Technology with support from ÅF Automotive in Trollhättan. The work aims to parameterize driving characteristics with engineering requirements, evaluate how the rolling resistance can be minimized, how negative driving characteristics can be minimized and a weight comparison with wheel suspension from 2017. This is the basis for the construction of the 2019 wheel suspension adapted for new body designed and manufactured in parallel with this work. The study includes performed measurements of the side force impact on steering angle change and camber change, calculation of load case, concept generation and evaluation, computer-aided strength evaluations. The results of the survey show great weaknesses in the 2017 solar car. In the case of an applied side force in the front wheel, a large wheel angle change occurs. This is largely due to under-dimensioned steering arms and the geometric design of the points. The influence of the side force on the steering angle has theoretically been reduced by at least 44% verified in CAD environment. In addition to this improvement, the entire wheel suspension system's attachments and sub-components are stiffer, which should contribute to an even greater improvement. The study also shows that the steering angle was insufficient to meet the competition requirements, which could be improved by 21.2% greater steering angle on the wheels. The spring and damper's operating ratio in comparison with the wheel has also been evaluated and has been able to be increased from 31% to 51.5%. This leads to reduced forces on the link arms and body by 20.5% during the same external load case. The study is limited to evaluating the hard points of the wheel suspension as well as the strength and design of the link arms, steering arm, suspension and damping attachment.
219

Modelagem matemática de processo de produção de PVC por polimerização em suspensão em reator de batelada. / Mathematical modelling of PVC production process by suspension polymerization in batch reactor.

Lacerda, Renata Argolo 18 March 2009 (has links)
O poli(cloreto de vinila) PVC é o segundo termoplástico mais consumido no mundo devido a sua versatilidade e seu amplo espectro de utilização. O desenvolvimento de modelos matemáticos representativos é de grande importância para o projeto, análise e otimização de processos de polimerização. A determinação das condições de operação ótimas para um reator de polimerização levando em conta as restrições operacionais e de qualidade do polímero produzido poderia, em princípio, ser realizada de maneira empírica. Entretanto, pode ser feita de maneira muito mais eficiente, econômica e segura através da solução de um problema de otimização. Para tanto, é imprescindível dispor de um modelo matemático representativo do processo de polimerização, confiável e validado experimentalmente em condições tão amplas quanto possível. Dentro deste panorama, o presente trabalho buscou desenvolver, a partir de modelos previamente descritos na literatura, um modelo matemático do processo de polimerização em suspensão de cloreto de vinila. Parâmetros do modelo referentes às limitações difusionais das constantes de terminação e propagação foram ajustados. As previsões do modelo foram comparadas com dados experimentais obtidos na literatura, referentes a diferentes tipos de iniciador, e diferentes condições operacionais. Verificou-se que o modelo desenvolvido foi capaz de representar adequadamente todos os dados experimentais testados quando ajustado individualmente para cada ensaio. Quando aplicada uma correlação generalizada para os parâmetros ajustáveis, o modelo representou de forma satisfatória, tanto qualitativa como quantitativamente, a maioria dos dados experimentais. As possíveis causas para as discrepâncias encontradas em alguns casos foram discutidas e recomendações para melhoramento do modelo foram apresentadas. / Poly (vinyl chloride) PVC is the second-largest thermoplastic that is consumed in the world because of its versatility and comprehensive series of application. The development of representative mathematical models is important for the design, analysis and optimization of polymerization processes. The determination of the optimal operational conditions for a polymerization reactor taking into account operational constraints and quality of the polymer produced could be, in principle, achieved by empirical trial-and-error procedure. However, this can be made in a much more efficient, economic, and safe way through the solution of an optimization problem for which it is required a representative mathematical model of the polymerization process. Such model should be reliable and validated over as wide a range of experimental conditions as possible. In this scenario, the objective of the present work was to develop a mathematical model for suspension polymerization of vinyl chloride, with the abovementioned features, from the models previously described in literature. Model parameters for the diffusion-controlled termination and propagation rate constant were estimated. The model predictions were compared with experimental data taken from the literature, covering different kinds of initiators and different operational conditions. It was found that the model was able to suitably represent all the experimental data tested when fitted for each run. When a general correlation for the adjustable parameters was obtained and included in the model, the model predictions reproduced satisfactorily most of the experimental data in both qualitative and quantitative fashions. Possible causes for the discrepancies found in some cases were discussed and recommendations for model improvement were suggested.
220

Adaptação de células CHO secretoras de prolactina humana e seus antagonistas para o crescimento em suspensão / Adaptation of CHO cells secreting human prolactin and their antagonists to growth in suspension

Arthuso, Fernanda dos Santos 11 February 2011 (has links)
O Grupo de Hormônios do Centro de Biotecnologia do IPEN desenvolveu várias linhagens de células de ovário de hamster chinês (CHO) modificadas geneticamente e comprovadamente eficientes na expressão de proteínas heterólogas, dentre elas a prolactina humana (hPRL) e os análogos antagonistas de prolactina (S179D-hPRL e G129R-hPRL). No entanto, todas as linhagens para expressão são cultivadas em monocamadas e dependentes da presença de soro fetal bovino (SFB) no meio de cultivo para um crescimento eficiente. As células em suspensão apresentam um grande interesse industrial-farmacêutico, tanto pela facilidade de cultivo e ampliação de escala, como pela produtividade volumétrica. Desenvolvemos um protocolo para adaptação de células CHO para o crescimento em suspensão e também processos de produção em frascos spinners. Nesse trabalho foi realizada a adaptação das linhagens produtoras de hPRL; S179D-hPRL e G129R-hPRL para o crescimento em suspensão e em meio livre de SFB. Realizamos também a produção em escala laboratorial com as três linhagens adaptadas, assim como a correspondente purificação e caracterização de quatro proteínas heterólogas, incluindo a prolactina humana glicosilada (G-hPRL). / The Hormone Group of the Biotechnology Center of IPEN has developed different cells lines of genetically modified chinese hamster ovary cells (CHO) for the expression of heterologus protein like human prolactin (hPRL) and its analogs/antagonists (S179D-hPRL and G129R-hPRL). All cell lines for expression are however cultured in monolayer culture dish and depend on fetal bovine serum (FBS) in the medium for an efficient growth. Cells in suspension show a great industrial-pharmaceutical interest, especially for the cultivation facility and scale enlargement as well as for volumetric productivity. We developed a protocol for adapting CHO cells to suspension growth, in spinner flasks. The adaption of our cell lines producing hPRL; S179D-hPRL and G129R-hPRL to suspension growth and in serum-free medium was obtained. We also carried out laboratory scale production with the three suspension-adapted culture line cells and the corresponding purification and characterization of four heterologous proteins, including glycosylated human prolactin (G-hPRL).

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