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Статті в журналах з теми "Instability constant"
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Monastra, A. G., M. F. Carusela, M. V. D’Angelo, and L. Bruno. "Filament instability under constant loads." Journal of Physics: Conference Series 1012 (April 2018): 012010. http://dx.doi.org/10.1088/1742-6596/1012/1/012010.
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Wallace, J. M., and E. M. Epperlein. "Weibel instability with constant driving source." Physics of Fluids B: Plasma Physics 3, no. 7 (July 1991): 1579–86. http://dx.doi.org/10.1063/1.859677.
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Çakırlı, Ö. "“Constant” eclipsing binary in the instability strip." New Astronomy 37 (May 2015): 70–75. http://dx.doi.org/10.1016/j.newast.2014.12.006.
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Alipour, M. J., and A. Lashkari. "Sand instability under constant shear drained stress path." International Journal of Solids and Structures 150 (October 2018): 66–82. http://dx.doi.org/10.1016/j.ijsolstr.2018.06.003.
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Petrov, A. G., and M. A. Yudin. "Cylinder instability in bounded flow with constant vorticity." Journal of Physics: Conference Series 894 (October 2017): 012126. http://dx.doi.org/10.1088/1742-6596/894/1/012126.
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Chan, San To, Stylianos Varchanis, Simon J. Haward, and Amy Q. Shen. "Torsional instability of constant viscosity elastic liquid bridges." Soft Matter 18, no. 10 (2022): 1965–77. http://dx.doi.org/10.1039/d1sm01804c.
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GIDDINGS, STEVEN B. "THE CONFORMAL FACTOR AND THE COSMOLOGICAL CONSTANT." International Journal of Modern Physics A 05, no. 19 (October 10, 1990): 3811–29. http://dx.doi.org/10.1142/s0217751x9000163x.
Повний текст джерелаАнотація:
The issue of the conformal factor in quantum gravity is examined for Lorentzian signature spacetimes. In Euclidean signature, the “wrong” sign of the conformal action makes the path integral undefined, but in Lorentzian signature this sign is tied to the instability of gravity and once this is accounted for the path integral should be well-defined. In this approach it is not obvious that the Baum-Hawking-Coleman mechanism for suppression of the cosmological constant functions. It is conceivable that since the multiuniverse system exhibits an instability for positive cosmological constant, the dynamics should force the system to zero cosmological constant.
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Matsebula, Lindiwe Fortunate. "Shoulder Function Following Latarjet Procedure for Recurrent Anterior Shoulder Instability." Journal of Orthopaedics & Bone Disorders 5, no. 1 (2021): 1–8. http://dx.doi.org/10.23880/jobd-16000205.
Повний текст джерелаАнотація:
Introduction: Anterior shoulder dislocation and recurrent glenohumeral instability is very common in the young active population. It is usually caused by trauma, and often compounded by associated bony Bankart and Hill-Sachs lesions, which distort the anatomy. This causes instability and dysfunction of the joint and these can be addressed by, amongst others, a Latarjet surgical procedure. Hypothesis: We hypothesize that since the Latarjet procedure results in stability and good functional outcome, our results are expected to compare favourably to the rest of the published literature. Methods: A retrospective study of 31 patients treated with the Latarjet procedure at Helen Joseph hospital, Johannesburg South Africa was undertaken during the period of January 2005 to December 2013. The minimum follow up was 6 months. Stability was assessed looking at re-dislocation rate and the clinical functional outcome was measured using the Constant Score. Results: There were no shoulder re-dislocations and the mean Constant score was 85.35. 74% had a Constant Score above 80. 68% were pain free and 61% had normal activities of daily living while 68% had a full range of motion and 68% had full power. Conclusion: The Latarjet results in stability and good functional outcome. In our patient cohort, the Latarjet procedure provided reliable stability to the shoulder joint. Pain was alleviated, shoulder muscle power was preserved, range of shoulder motion was restored and patients did return to pre injury activities of daily living.
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Obligado, Martín, Nathanaël Machicoane, Agathe Chouippe, Romain Volk, Markus Uhlmann, and Mickaël Bourgoin. "Path instability on a sphere towed at constant speed." Journal of Fluids and Structures 58 (October 2015): 99–108. http://dx.doi.org/10.1016/j.jfluidstructs.2015.08.003.
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Tahiri, Abdellah, Mohamed Idiri, and Brahim Boubeker. "Mechanicals Behaviors of Tungsten-Rhenium Alloy Single Crystals from 77K to 300K - Atomic Simulation Study." International Journal of Engineering Research in Africa 50 (September 2020): 177–81. http://dx.doi.org/10.4028/www.scientific.net/jera.50.177.
Повний текст джерелаАнотація:
The elastic constants of tungsten-rhenium alloy single crystals were calculated by simulation atomic method using embedded method atom of interatomic potential. The found results show that elastic constants are proportional to the rhenium concentration up to 25 at% Re at room temperature. By following, we observed the elastic constant C44 dependency of temperature and decreased of elastic constant C’=1/2(C11-C12) when the Re atom addition increases. We have found that a growing instability of the bcc crystal structure. Our parameter calculation model is in good agreement with experimental data.
Дисертації з теми "Instability constant"
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Tyagi, P. K. "Linear Instability Of Laterally Strained Constant Pressure Boundary Layer Flows." Thesis, Indian Institute of Science, 2001. http://hdl.handle.net/2005/265.
Повний текст джерелаАнотація:
The linear instability of laterally diverging/converging flows is an important aspect towards understanding the laminar-transition process in many viscous flows. In this work the linear instability of constant pressure laterally diverging/converging flow has been investigated.
The laminar velocity field for laterally diverging/converging flows, under the source/sink approximation, has been reduced to two-dimensional flows. This reduction is alternative to the Mangier transformation used earlier. For a constant pressure laterally strained flow, the laminar velocity is found to be governed by the Blasius equation for flow over a flat plate.
The non-parallel linear instability of constant pressure laterally strained flows has been examined. The instability equation is found to be same as that for the Blasius flow. This implies that the stability is same as that for the Blasius flow. A lateral divergence/convergence is shown to alter the Reynolds number from that in a two-dimensional flow. The instability of a laterally converging/diverging flow thus can be obtained from the available results for the Blasius flow by scaling the Reynolds numbers. This leads to the result that while a diverging flow is more unstable than the Blasius flow, a converging flow is more stable. Some additional relevant results are also presented.
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Bahadornejad, Momen. "On-line local load measurement based voltage instability prediction." Queensland University of Technology, 2005. http://eprints.qut.edu.au/16187/.
Повний текст джерелаАнотація:
Voltage instability is a major concern in operation of power systems and it is well known that voltage instability and collapse have led to blackout or abnormally low voltages in a significant part of the power system. Consequently, tracking the proximity of the power system to an insecure voltage condition has become an important element of any protection and control scheme. The expected time until instability is a critical aspect. There are a few energy management systems including voltage stability analysis function in the real-time environment of control centres, these are based on assumptions (such as off-line models of the system loads) that may lead the system to an insecure operation and/or poor utilization of the resources. Voltage instability is driven by the load dynamics, and investigations have shown that load restoration due to the on-load tap changer (OLTC) action is the main cause of the voltage instability. However, the aggregate loads seen from bulk power delivery transformers are still the most uncertain power system components, due to the uncertainty of the participation of individual loads and shortcomings of the present approaches in the load modeling. In order to develop and implement a true on-line voltage stability analysis method, the on-line accurate modeling of the higher voltage (supply system) and the lower voltage level (aggregate load) based on the local measurements is required. In this research, using the changes in the load bus measured voltage and current, novel methods are developed to estimate the supply system equivalent and to identify load parameters. Random changes in the load voltage and current are processed to estimate the supply system Thevenin impedance and the composite load components are identified in a peeling process using the load bus data changes during a large disturbance in the system. The results are then used to anticipate a possible long-term voltage instability caused by the on-load tap changer operation following the disturbance. Work on the standard test system is provided to validate the proposed methods. The findings in this research are expected to provide a better understanding of the load dynamics role in the voltage stability, and improve the reliability and economy of the system operation by making it possible to decrease uncertainty in security margins and determine accurately the transfer limits.
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Nguyen, Kien Trung. "Etude expérimentale du comportement instable d'un sable silteux : application aux digues de protection." Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM4709/document.
Повний текст джерелаАнотація:
Les matériaux constitutifs des digues sont souvent des sables silteux dont le comportement mécanique peut manifester une « instabilité » à des états de contraintes situés bien avant la limite de plasticité de Mohr-Coulomb. Ce mécanisme de rupture pourrait expliquer plusieurs brèches dont l'occurrence n'a pas été attribuée aux mécanismes classiques de rupture de digues telle que l'érosion interne. L'objectif de cette thèse est de mieux comprendre, au regard de ce phénomène d'instabilité, le comportement mécanique d'un sable silteux provenant de la zone adjacente à une brèche de digue du Rhône lors de la crue de 2003, à l'aide d'essais triaxiaux.Les résultats sur le sable propre montrent que le matériau étudié est très sensible au phénomène d'instabilité. Ce dernier peut être prédit par une courbe d'instabilité reliant, au déclenchement de l'instabilité, le rapport des contraintes au paramètre d'état. L'analyse de ces résultats suggère qu'une forte contractance du matériau est la condition nécessaire pour que l'instabilité du sable lâche ait lieu et qu'une direction appropriée du vecteur d'incrément de contraintes est la condition suffisante.Les résultats sur les mélanges constitués du sable avec des fines montrent qu'un départ de fines, causé par exemple une érosion de type suffusion, favorise l'occurrence de l'instabilité dans les digues. Par ailleurs, ces résultats révèlent que l'indice des vides équivalent est un paramètre pertinent dans l'analyse du comportement du sable silteux. Le calcul de l'indice des vides équivalent nécessite la détermination du paramètre b pour lequel une nouvelle formule a été proposéeThe constitutive materials of dikes are often silty sands whose mechanical behavior can become unstable at stress states located well under the Mohr-Coulomb plasticity limit criterion. This failure mechanism could explain several dike breaches whose occurrence has not been assigned to conventional mechanisms of dike failure such as internal erosion. The objective of this thesis is to better understand, with respect to the instability phenomenon, the mechanical behavior of a silty sand which is collected in the area adjacent of a breach of the Rhone embankment dike during the flood of 2003, by means of triaxial tests.The test results obtained on clean sand show that this material is very sensitive to the instability phenomenon. The occurrence of the latter can be predicted by an instability curve relating, at the onset of instability, the stress ratio to the state parameter. The analysis of these results suggests that a strong contractiveness of the material is the necessary condition for instability of loose sand and an appropriate direction of stress increment vector is the sufficient condition.The test results obtained on mixtures of sand with fines show that a removal of fine particles caused by an erosion, such as suffusion for example, favors the occurrence of instability in the dikes. Moreover, these results indicate that the equivalent void ratio is a relevant parameter in analyzing the behavior of silty sand. The calculation of the equivalent void ratio requires the determination of the parameter b for which a new formula has been proposed
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Yogi, Leda Shizuka. "Estudo comparativo entre métodos de avaliação funcional do ombro nas cirurgias de descompressão subacromial e capsuloplastia: avaliação de 60 pacientes com os métodos ASES, CONSTANT, ROWE, SF-36, SST e UCLA shoulder rating." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/5/5140/tde-30052007-152653/.
Повний текст джерелаАнотація:
Realizamos estudo prospectivo randomizado para comparar cinco métodos específicos de avaliação funcional do ombro e uma avaliação genérica da saúde em pacientes operados de capsuloplastia e descompressão subacromial associado à reparação do manguito rotador. Foram estudados 30 pacientes de cada grupo, avaliados no período entre cinco a seis meses após o tratamento cirúrgico com os questionários dos Cirurgiões Americanos de Ombro e Cotovelo(ASES), Sistema de Pontuação do Ombro de Constant & Murley (CONSTANT), Folha de Classificação da Reparação de Bankart (ROWE), Teste Simples de Ombro (SST), Escala de Avaliação do Ombro da Universidade de Califórnia - Los Angeles (UCLA) e o Questionário Genérico de Avaliação de Qualidade de Vida (SF-36). A idade no grupo de \"Descompressão\" variou de 44 a 77 anos (média 59,2) e no grupo de \"Capsuloplastia\" foi de 17 a 65 anos (média de 31,4). Em relação ao sexo, o grupo da \"Descompressão\" foi predominantemente feminino e no grupo da \"Capsuloplastia\" foi predominante o sexo masculino. As médias da pontuação no grupo de \"Capsuloplastia\" são maiores que no \"Descompressão\" (93,6 e 71,7 respectivamente). A variabilidade dos escores observado no grupo \"Capsuloplastia\" (89,1 a 100) é inferior ao do grupo \"Descompressão\" (65,1 a 95,9). Não existe uma forte concordância entre os resultados obtidos pelos diferentes questionários (variação de zero a 0,51). A média nos oito domínios do SF-36 no grupo \"Descompressão\" foi de 70,8 variando de 60,4 (Vitalidade) a 89,2 (Aspectos Sociais). Para o grupo \"Capsuloplastia\" a média foi de 91,2 variando de 83,4 (Saúde Mental) a 96,6 (Aspectos Emocionais). Nos coeficientes de correlação linear de Pearson, não foi detectada associação linear entre a escala de CONSTANT e SF-36 no grupo \"Descompressão\" e entre ROWE e SF-36 no grupo \"Capsuloplastia\". Em ambos os grupos a maior correlação encontrada foi entre os questionários UCLA e ASES (0,900 na \"Descompressão\" e 0,893 na \"Capsuloplastia\"). Concluiu-se que nas cirurgias de descompressão subacromial o questionário UCLA foi o mais completo mostrando maior confiabilidade e reprodutibilidade e para as capsuloplastias o método ROWE apresentou maior confiabilidade, reprodutibilidade e praticidade.A prospective randomized study was realized to compare methods of both disease specific and generic health status of shoulder\'s functional assessment in patients after operative treatment of subacromial decompression associated a repair of a tear of the rotator cuff and capsuloplasty. The thirty patients in each group were studied and at follow-up five to six months later, with the following questionnaires: American Shoulder and Elbow Surgeons Shoulder Evaluation Form (ASES), Constant-Murley Shoulder Scoring System (CONSTANT), Rating Sheet for Bankart Repair (ROWE), Simple Shoulder Test (SST), University of California at Los Angeles Shoulder Rating Scale (UCLA) and the Short Form-36 (SF-36). The age in Decompression group was greater than Capsuloplasty group and the gender of first group was predominantly consisted of women and in the second group was men. The scores averages of Capsuloplasty group were higher than Decompression group (93,6 and 71,7 respectively). The variability of the scores observed in the Capsuloplasty group, 89,1 to 100,0 was less than in the Decompression group, 65,1 to 95,9. A strong interrater reliability between the questionnaires does not exist - variation 0 to 0,51. The average in the eight domains of SF-36 in Decompression group was 70,8 [range 60,4 (Vitality) to 89,2 (Social Aspect)]. In Capsuloplasty group the average was 91,2 [range 83,4 (Mental Health) to 96,6 (Emotional Aspect) ]. Pearson\'s coefficient analysis, shows that the correlation between CONSTANT and SF-36 was not detect, and in Capsuloplasty was not detect in ROWE and SF-36. In both groups Capsuloplasty (0,893) and Decompression (0,900), a strong correlation between UCLA and ASES were observed. It follows that to subacromial decompression surgery, UCLA shows more reliability and in Capsuloplasty, the Rowe method shows more applicability.
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Гапон, Юліана Костянтинівна. "Функціональні покриття тернарними сплавами кобальту з тугоплавкими металами". Thesis, НТУ "ХПІ", 2017. http://repository.kpi.kharkov.ua/handle/KhPI-Press/27602.
Повний текст джерелаАнотація:
Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.17.03 – технічна електрохімія. – Національний технічний університет "Харківський політехнічний інститут", м. Харків, 2017 р.
Дисертацію присвячено розробці технології гальванохімічного синтезу покриттів тернарними сплавами кобальт-молібден-вольфрам з полілігандних електролітів для одержання матеріалів з поліпшеними фізико-механічними властивостями. Визначено константи нестійкості та склад моно- та білігандних комплексів кобальту та запропоновано цитратно-дифосфатну та амонійно-цитратну системи для осадження сплавів кобальту з вольфрамом та молібденом. На підставі аналізу кінетичних закономірностей встановлено механізм осадження сплаву. Із цитратно-дифосфатного електроліту відбувається стадійне відновлення металів з гетероядерних комплексів складу [MO₄Со(P₂O₇)]⁴⁻, де М = Mo, W та Со(Cit)₂⁴⁻, а з амонійно-цитратного електроліту спряжений процес відновлення реалізується за участю комплексів [MO₄Со(Cit)]³⁻. Обґрунтовано вплив складу електролітів та режимів осадження (стаціонарний та імпульсний) на вміст компонентів, морфологію, структуру, функціональні властивості та ефективність процесу. Запропоновано технологічну схему електролітичного формування функціональних покриттів сплавами кобальту з молібденом і вольфрамом та розроблено відповідні технологічні інструкції. Встановлено високу корозійну стійкість покриттів і нададитвне зростання мікротвердості та каталітичної активності порівняно з вихідними компонентами сплаву.Thesis for the Degree of Candidate of Technical sciences in specialty 05.17.03 – Technical Electrochemistry. – National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2017. The thesis is devoted to development of technologies for galvanic coatings synthesis of the ternary alloys cobalt-molybdenum-tungsten from poly-ligand electrolytes to produce materials with improved physical and mechanical properties. The constant instability and composition of mono- and bi-ligand complexes of cobalt are determined, and both citrate-diphosphate and ammonia-citrate systems suggested for the deposition of cobalt alloys with tungsten and molybdenum. The mechanism of alloy deposition is defined based on kinetic patterns analysis. Metals recovered by stages from hetero-nuclear complexes of composition [MO₄Со(P₂O₇)]⁴⁻ and mononuclear Со(Cit)₂⁴⁻ (where M = Mo, W) when deposited from citrate-diphosphate bath. Conjugate deposition of metals in alloy from ammonia-citrate electrolyte occurred from complexes [MO₄Со(Cit)]³⁻. The effect of electrolytes composition and deposition modes (stationary and pulse) on the components content, morphology, structure and functional properties of alloys as well as process efficiency are substantiated. A technological scheme for functional electrolytic cobalt alloy coatings deposition with molybdenum and tungsten is offered and relevant technological instructions are developed. It was established high corrosion resistance coatings, synergic growth of microhardness and catalytic activity compared with alloying components.
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Гапон, Юліана Костянтинівна. "Функціональні покриття тернарними сплавами кобальту з тугоплавкими металами". Thesis, НТУ "ХПІ", 2017. http://repository.kpi.kharkov.ua/handle/KhPI-Press/27601.
Повний текст джерелаАнотація:
Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.17.03 – технічна електрохімія. – Національний технічний університет "Харківський політехнічний інститут", м. Харків, 2017 р.
Дисертацію присвячено розробці технології гальванохімічного синтезу покриттів тернарними сплавами кобальт-молібден-вольфрам з полілігандних електролітів для одержання матеріалів з поліпшеними фізико-механічними властивостями. Визначено константи нестійкості та склад моно- та білігандних комплексів кобальту та запропоновано цитратно-дифосфатну та амонійно-цитратну системи для осадження сплавів кобальту з вольфрамом та молібденом. На підставі аналізу кінетичних закономірностей встановлено механізм осадження сплаву. Із цитратно-дифосфатного електроліту відбувається стадійне відновлення металів з гетероядерних комплексів складу [MO₄Со(P₂O₇)]⁴⁻, де М = Mo, W та Со(Cit)₂⁴⁻, а з амонійно-цитратного електроліту спряжений процес відновлення реалізується за участю комплексів [MO₄Со(Cit)]³⁻. Обґрунтовано вплив складу електролітів та режимів осадження (стаціонарний та імпульсний) на вміст компонентів, морфологію, структуру, функціональні властивості та ефективність процесу. Запропоновано технологічну схему електролітичного формування функціональних покриттів сплавами кобальту з молібденом і вольфрамом та розроблено відповідні технологічні інструкції. Встановлено високу корозійну стійкість покриттів і нададитвне зростання мікротвердості та каталітичної активності порівняно з вихідними компонентами сплаву.Thesis for the Degree of Candidate of Technical sciences in specialty 05.17.03 – Technical Electrochemistry. – National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2017. The thesis is devoted to development of technologies for galvanic coatings synthesis of the ternary alloys cobalt-molybdenum-tungsten from poly-ligand electrolytes to produce materials with improved physical and mechanical properties. The constant instability and composition of mono- and bi-ligand complexes of cobalt are determined, and both citrate-diphosphate and ammonia-citrate systems suggested for the deposition of cobalt alloys with tungsten and molybdenum. The mechanism of alloy deposition is defined based on kinetic patterns analysis. Metals recovered by stages from hetero-nuclear complexes of composition [MO₄Со(P₂O₇)]⁴⁻ and mononuclear Со(Cit)₂⁴⁻ (where M = Mo, W) when deposited from citrate-diphosphate bath. Conjugate deposition of metals in alloy from ammonia-citrate electrolyte occurred from complexes [MO₄Со(Cit)]³⁻. The effect of electrolytes composition and deposition modes (stationary and pulse) on the components content, morphology, structure and functional properties of alloys as well as process efficiency are substantiated. A technological scheme for functional electrolytic cobalt alloy coatings deposition with molybdenum and tungsten is offered and relevant technological instructions are developed. It was established high corrosion resistance coatings, synergic growth of microhardness and catalytic activity compared with alloying components.
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Renaudière, de Vaux Sébastien. "Convection thermique en présence d'un champ magnétique constant, alternatif, ou d'une source de chaleur dispersée." Phd thesis, Toulouse, INPT, 2017. http://oatao.univ-toulouse.fr/19752/1/renaudiere.pdf.
Повний текст джерелаАнотація:
On s’intéresse dans ce travail à la convection thermique en présence de champ magnétique, en lien avec les essais Vulcano du CEA de Cadarache. Ces essais ont pour but de reproduire en laboratoire les écoulements générés par un chauffage volumique dues aux matières radioactives issues d’accidents nucléaires. Le chauffage par induction électromagnétique de ces fluides permet de simuler en laboratoire la puissance volumique des désintégrations nucléaires en évitant l’utilisation de matériaux radioactifs. Néanmoins, ce forçage électromagnétique génère un couplage entre l’écoulement fluide et le champ magnétique, par la force de Lorentz d’une part, et d’autre part le chauffage volumique par effet Joule se concentre dans l’épaisseur de peau. De plus, il peut y avoir dans ces essais présence d’une phase dispersée métallique qui risque de perturber le chauffage inductif de la phase continue (oxyde). Il est nécessaire d’étudier comment ces effets d’origine électromagnétique modifient l’écoulement. À plus petite échelle, les phénomènes magnétiques en jeu peuvent être reproduits grâce à des métaux liquides à température ambiante. Lorsqu’un champ magnétique harmonique est appliqué à la frontière d’un métal liquide, l’effet stabilisant de la force de Lorentz sera prépondérant devant l’effet Joule à basses fréquences, alors que l’effet Joule devient significatif à hautes fréquences. On considère alors plusieurs situations canoniques permettant d’analyser l’effet d’un champ magnétique constant DC et alternatif AC sur un écoulement de convection naturelle monophasique, ou en présence d’une phase dispersée très conductrice. Une première partie est consacrée à l’étude expérimentale d’une méthode de vélocimétrie acoustique sur une cellule de convection naturelle en eau. Par comparaison avec des mesures de vitesse par imagerie de particules (PIV) et des simulations numériques directes (DNS), cela a permis de valider la méthode acoustique en vue de futures expériences en métal liquide. Une seconde étude est dédiée à l’analyse numérique de l’instabilité de Rayleigh-Bénard en présence d’un champ magnétique DC vertical. Les taux de croissance sont déterminés par analyse de stabilité linéaire pour des nombres de Hartmann 0 _ Ha _ 100 et des nombres de Rayleigh 103 _ Ra _ 1.5 × 105. Ces prédictions sont confirmées par DNS. En régime stationnaire, l’analyse des DNS a permis de mettre en évidence un effet marqué de la force de Lorentz sur les structures, à travers leur nombre d’onde et leur orientation. La troisième configuration étudiée est le chauffage inductif d’une couche de métal liquide en imposant un champ magnétique harmonique au niveau de la paroi basse pour des nombres de Rayleigh proportionnels à la puissance déposée 1.1×104 _ Ra _ 1.2×105 et pour des épaisseurs de peau inférieures à la moitié de l’épaisseur de liquide. Dans ce cas, les courants induits sont dissipés par effet Joule sur l’épaisseur de peau. La prédiction des taux de croissance requiert l’utilisation de méthodes adaptées car ici le développement de l’instabilité est concomitant à la conduction instationnaire de la chaleur. Malgré la perte de symétrie des équations introduite par le terme source d’effet Joule, l’écoulement présente une symétrie de réflexion apparente, que ce soit en régimes transitoire ou stationnaire. Cela est lié au brassage conséquent par convection naturelle. Enfin une situation modèle de particules métalliques immergées dans un liquide transparent au champ magnétique est étudiée. Ici, l’énergie magnétique est dissipée sous forme thermique dans les particules, qui transmettent toute leur chaleur au fluide. Des mouvements convectifs se mettent alors en place. La convection est décrite par la concentration relative en particules. Selon les valeurs des paramètres, on observe la formation d’amas de particules en réponse au panache qu’elles génèrent.
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Cariolle, Joël. "Export instability, corruption and how the former influences the latter." Thesis, Clermont-Ferrand 1, 2013. http://www.theses.fr/2013CLF10419.
Повний текст джерелаАнотація:
Cette thèse a pour objectif d’approfondir l’analyse des conditions d’émergence et d’incidence de la corruption dans le monde. Nous y soulignons une dimension importante mais jusque-La peu documentée des activités de corruption, à savoir, leur contribution aux stratégies informelles d’adaptation et de gestion du risque mises en place par les agents économiques pour se protéger contre l’instabilité de leur revenu. Le premier chapitre propose un état des lieux de la recherche sur les définitions, les mesures, les typologies et les déterminants de la corruption. Dans le deuxième chapitre, les méthodes usuelles de calcul de l’instabilité macroéconomique sont expliquées, sont appliquées aux données sur les recettes d'exportation d’un échantillon de pays développes et en développement, et sont comparées entre elles. Le troisième chapitre présente et analyse une base de données rétrospectives sur l’Indice de Vulnérabilité Économique, reflétant le risque pour un pays de voir son développement entravé par des chocs naturels et des chocs d’exportations, que nous avons calculé pour un échantillon de 128 pays en développement et couvrant la période 1975- 2008. Dans le quatrième chapitre, nous analysons les effets de l’instabilité des exportations sur la corruption dans les pays développés et en développement. Ces effets sont décomposés en un effet ex post, résultant de l’expérience des agents économiques de l’instabilité des exportations, et un effet ex ante, résultant de leur perception de cette dernière. Nous testons empiriquement ces effets sur les perceptions de la corruption et sur les pots-De-Vin payés par les entreprises. Nous mettons en évidence des effets robustes, significatifs et non linéaires, dont le signe dépend de la fréquence et de la taille des chocs d’exportations. Nos résultats suggèrent également que la contrainte de liquidité est un canal transmission clé de ces effets: lorsque la contrainte de liquidité est forte l’instabilité des exportations aggrave l’incidence à la corruption, alors qu’elle la réduit lorsque cette contrainte se relâche. Ainsi, en l’absence d’État et de marches financiers capables d’atténuer les effets de l’instabilité sur les performances économiques et le bien-Être, il est probable que les agents économiques aient recours à la corruption pour se protéger contre les fluctuations économiquesThis thesis is an attempt to improve the understanding of the causes of corruption emergence and incidence around the world. It highlights an undocumented feature of corrupt transactions, that is, their contribution to informal risk-Coping and risk-Management mechanisms used by economic agents to protect against income fluctuations. We propose in a first introductory chapter a general state of art of researches on corruption definitions, measurements, typologies and determinants. In chapter two, we explain, apply and compare standard methods of computing instability indicators, using export revenue data from sample of developed and developing countries. In chapter three, we build a retrospective Economic Vulnerability Index – i.e. an index reflecting the risk for a country of seeing its development hampered by natural and trade shocks – for a sample of 128 developing countries over 1975-2008. In chapter 4, we analyse the effect of export instability on corruption in developed and developing countries. This effect is decomposed into an ex post effect, resulting from agents’ experience of export instability, and an ex ante effect, resulting from their perception of export instability. We test empirically these effects using data on corruption perceptions and on firms’ bribe payments. We find robust, significant and nonlinear ex post and ex ante effects of instability on corruption, and stress that their direction strongly depends on the frequency and size of export fluctuations. We show that the liquidity constraint is a key channel for these effects: when the liquidity constraint hardens, instability is found to foster corruption; while when it softens, instability is found to reduce it. Thus, corrupt strategies may act as a substitute for financial market imperfections and a low state capacity for mitigating the consequences of economic fluctuations on welfare
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Laghmach, Rabia. "Modélisation de la cristallisation des élastomères sous sollicitation mécanique par champ de phase." Thesis, Lyon, INSA, 2014. http://www.theses.fr/2014ISAL0061/document.
Повний текст джерелаАнотація:
La cristallisation induite par déformation des élastomères est un processus cinétique qui conduit à la formation de nano-cristallites thermodynamiquement stables. La présence de ces nano-cristallites au sein de la phase amorphe modifie considérablement les propriétés mécaniques des élastomères cristallisables. Ces élastomères ont en effet la propriété intéressante d'être auto-renforçants. L’objectif de ce travail est de développer un modèle physique capable de décrire localement l’évolution de la microstructure sous l’effet d’un champ de contrainte élastique durant la cristallisation. Dans ce but, un modèle de champ de phase est élaboré et mis en œuvre dans le cadre de la mécanique des milieux continus en couplant thermodynamique et mécanique avec une dynamique de transition de phase d’Allen-Cahn. La description thermodynamique de la cristallisation induite par déformation à petite échelle est basée sur la fonctionnelle d’énergie libre du système amorphe-cristal. Les conséquences du choix de cette formulation sont discutées, on étudie en particulier les effets de contraintes élastiques sur l’équilibre des phases en volumes ainsi que sur la cinétique de croissance des domaines cristallins au sein de l’amorphe. L’introduction de l’élasticité du réseau des contraintes topologiques induite par les enchevêtrements et/ou les nœuds de réticulation dans le modèle de champ de phase a permis de mettre en évidence l’existence d’un état stable de cristallites formées (modèle énergétique) mais aussi des instabilités de croissance (modèle cinétique). Sur la base de ces deux modèles, cinétique et énergétique, nous avons étudié systématiquement l’influence des contraintes topologiques sur la cinétique de croissance et nous montrons que cette cinétique est en effet contrôlée par l’accumulation de contraintes élastiques à l’interface. La prise en compte de l’élasticité du réseau des contraintes topologiques dans l’approche thermodynamique de cristallisation prédit une augmentation de la tension de surface et par conséquent un arrêt du mécanisme de croissance en donnant lieu à la formation de cristallites stables. Enfin, nous avons adopté le modèle énergétique pour modéliser le couplage entre nucléation, croissance et déformation cyclique. Pour valider le modèle local proposé une comparaison entre les résultats des simulations par champ de phase et les données expérimentales issues de la caractérisation d’un caoutchouc naturel réticulé est effectuée et nous montrons qualitativement l’accord entre l’expérience et le modèleNatural rubber NR and more generally elastomer presents unique physical properties that are very important for many engineering applications. Strain induced crystallization of elastomer presents a major interest because it improves considerably the mechanical properties. In fact, the presence of crystallites within the amorphous phase in a polymer network induces a strengthening of this material, giving NR a self-reinforcement character. In this thesis, we develop a mesoscopic model to describe the crystallization of elastomers under strain. In this context, we present a kinetic model using a new physical approach: a phase field model. This model combines the crystallization thermodynamics with the local stress field. The thermodynamic description of the phase transition is based on a Gibbs free energy functional F which contains all energy contributions of the system: the bulk contributions (enthalpy and entropy) and surface tension. To understand the experimental observation of nanometer size crystalites, an explicit account of the topological constraints induced by both entanglements and/or crosslinks is necessary. We investigated two limiting mechanisms, a kinetic limitation of the growth, and an energetic limitation. Based on both the kinetic and the energetic approaches, we have systematically studied the influence of topological constraints on the growth process. We have shown that the growth process is affected by the accumulation of elastic stress at the interface. The kinetic model predicts the existence of instabilities during the growth. These instabilities induce a heterogeneous dynamical growth which leads to the formation of dendrite like structures. On the contrary, the energetic approach predicts an exponential increase of the surface tension during the growth that limits the size of the crystallites very efficiently. In the last part we investigated elastomer crystallization under cyclic deformation. To this end, we coupled the previous energetic model with the nucleation process. Finally the simulation data are compared with experimental measurements
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Asker, Christian. "Effects of disorder in metallic systems from First-Principles calculations." Doctoral thesis, Linköpings universitet, Teoretisk Fysik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-53584.
Повний текст джерелаАнотація:
In this thesis, quantum-mechanical calculations within density-functional theory on metallic systems are presented. The overarching goal has been to investigate effects of disorder. In particular, one of the properties investigated is the bindingenergy shifts for core electrons in binary alloys using different theoretical methods. These methods are compared with each other and with experimental results. One such method, the so-called Slater-Janak transition state method relies on the assumption that the single-particle eigenvalues within density-functional theory are linear functions of their respective occupation number. This assumption is investigated and it is found that while the eigenvalues to a first approximation show linear behavior, there are also nonlinearities which can influence the core-level binding energy shifts. Another area of investigation has been iron based alloys at pressures corresponding to those in the Earth’s inner core. This has been done for the hexagonal close packed and face entered cubic structures. The effects of alloying iron with magnesium and nickel on the equation of state as well on the elastic properties have been investigated. The calculations have shown that the hexagonal close packed structure in FeNi is more isotropic than the face-centered cubic structure, and that adding Mg to Fe has a large impact on the elastic properties. Finally, the effects of disorder due to thermal motion of the atoms have been investigated through ab-initio molecular dynamics simulations. Within the limits of this method and the setup, it is found that the face-centered cubic structure of molybdenum can be dynamically stabilized at high temperature, leading to a metastable structure, on the average. The dynamical stabilization of face-centered cubic molybdenum also rendered it possible to accurately calculate the lattice stability relative to the body-centered cubic phase. Inclusion of temperature effects for the lattice stability using ab-initio molecular dynamics simulations resolves the disagreement between ab-initio calculations and thermochemical methods.
Книги з теми "Instability constant"
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Yatsimirskii, K. B., and V. P. Vasil’ev. Instability Constants of Complex Compounds. Boston, MA: Springer US, 1995. http://dx.doi.org/10.1007/978-1-4684-8404-5.
Повний текст джерела
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Todor, Arpad, ed. Willing to Pay? The Politics of Engendering Faith in the Post-Communist Romanian Tax System. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198796817.003.0011.
Повний текст джерелаАнотація:
Although the Romanian institutional landscape and its policies have dramatically improved since the 1990s, the low institutional capacity of its tax system remains mysteriously constant, despite continued efforts at improvement in this area and the fact that experimental data show that Romanians have apparently high tax morale. This puzzling situation is tackled in this chapter by detailing the institutional legacies upon which the post-Communist tax system has been built and tracing the evolution of tax policies over a quarter of a century within the context of post-Communist transformations. The chapter offers a nuanced explanation based on a combination of policy inadequacy and instability, tax evasion and corruption, and low spending on infrastructure, all of which limit the chances of creating an adequate legitimacy for the tax system.
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Uva, Christian. Sergio Leone. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190942687.001.0001.
Повний текст джерелаАнотація:
Spectacle, myth, fable. These are the main categories that have traditionally defined Sergio Leone’s cinematic production, but it is necessary to underline how much they are fueled by a profound, layered political interest. Leone’s cinema bears witness to a critical outlook both on the subjects it showcases and on its representational means. Far from any militancy and escaping ideological classifications, Leone’s perspective is problematic and unreconciled: it is grounded in the coexistence of different elements in a state of perennial productive tension and instability. The adjective “political” takes on a deeper meaning when it is used to denote the director’s ability to narrate and interpret key aspects of Italian national identity and history. The abstract quality of his production relies on an original use of different genres, particularly sword-and-sandal and the Spaghetti Western, which allowed Leone to insert frequent symbolic references to both history and then-current events. On the stylistic level, his constant disobedience to classical models and his need to revolutionize forms were motivated by an authorial desire to make films politically, though still within a conception of cinema as an industrial spectacle.
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Brown, Katherine E. Violence and Gender Politics in the Proto-State “Islamic State”. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780190644031.003.0011.
Повний текст джерелаАнотація:
This chapter explores the idea of the so-called Islamic State, also known as Daesh, as a proto-state. A proto-state operates in an environment of extreme instability but also, like the nucleus of an atom, manages to generate cohesion and structural integrity while constantly in flux. Because of this condition, and despite rejecting both nationalism and statehood in Islamic State’s rhetoric, this chapter argues that Daesh remains dependent on both. This is demonstrated by exploring the ideal-figure types of the “Muslimwoman” and the “warrior-monk,” and through understanding the organized public violence on the streets of its territory. The chapter reveals how these both transcend and depend upon nationalism and statism to create forms of authority and legitimacy for Daesh.
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Sim, Stuart. Bunyan, Poststructuralism, and Postmodernism. Edited by Michael Davies and W. R. Owens. Oxford University Press, 2018. http://dx.doi.org/10.1093/oxfordhb/9780199581306.013.31.
Повний текст джерелаАнотація:
This chapter surveys examples of the use of poststructuralist and postmodernist theory to analyse Bunyan’s work. The primary concerns and general agenda of poststructuralist/postmodernist theory are identified to assess their applicability to Bunyan’s writings (particularly his fiction and spiritual autobiography), focusing on the concepts of difference, différance, discourse, grand and little narratives, and the differend, as outlined in the work of Jean-François Lyotard, Jacques Derrida, and Michel Foucault. It is argued that such theories emphasize instability, and that this was a prominent feature of life in later seventeenth-century England: a period of considerable socio-political turmoil in which various ideological narratives were vying for power. Bunyan is seen to be someone constantly struggling against difference, différance, and differends: a factor that renders his writings particularly receptive to poststructuralist/postmodernist readings.
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Bebbington, Anthony, Abdul-Gafaru Abdulai, Denise Humphreys Bebbington, Marja Hinfelaar, Cynthia A. Sanborn, Jessica Achberger, Celina Grisi Huber, Verónica Hurtado, Tania Ramírez, and Scott D. Odell. Political Settlements, Natural Resource Extraction, and Inclusion in Bolivia. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198820932.003.0003.
Повний текст джерелаАнотація:
Bolivia’s natural resources have served as a ‘mechanism of trade’ mobilized by competing interest groups to build coalitions, create political pacts, and negotiate political settlements in which dominant actors attempt to win over those resistant to a particular vision of development and/or governance. These pacts and settlements are revisited constantly, reflecting the weak and fragmented power of the central state and of the elite and persistent tensions between national and subnational elites. Ideas about, and modes of, natural resource governance have been central to periods of instability and stability, and to significant periods of political rupture. The period since 2006 has been characterized by a stable settlement involving an alliance between the presidency, his dominant party, and national social movements. This settlement is sustained through bargains with parts of the economic elite and subnational actors with holding power, as well as through ideas of resource nationalism and state-led developmentalism.
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Shengelia, Revaz. Modern Economics. Universal, Georgia, 2021. http://dx.doi.org/10.36962/rsme012021.
Повний текст джерелаАнотація:
Economy and mankind are inextricably interlinked. Just as the economy or the production of material wealth is unimaginable without a man, so human existence and development are impossible without the wealth created in the economy. Shortly, both the goal and the means of achieving and realization of the economy are still the human resources. People have long ago noticed that it was the economy that created livelihoods, and the delays in their production led to the catastrophic events such as hunger, poverty, civil wars, social upheavals, revolutions, moral degeneration, and more. Therefore, the special interest of people in understanding the regulatory framework of the functioning of the economy has existed and exists in all historical epochs [A. Sisvadze. Economic theory. Part One. 2006y. p. 22]. The system of economic disciplines studies economy or economic activities of a society. All of them are based on science, which is currently called economic theory in the post-socialist space (the science of economics, the principles of economics or modern economics), and in most countries of the world - predominantly in the Greek-Latin manner - economics. The title of the present book is also Modern Economics. Economics (economic theory) is the science that studies the efficient use of limited resources to produce and distribute goods and services in order to satisfy as much as possible the unlimited needs and demands of the society. More simply, economics is the science of choice and how society manages its limited resources. Moreover, it should be emphasized that economics (economic theory) studies only the distribution, exchange and consumption of the economic wealth (food, beverages, clothing, housing, machine tools, computers, services, etc.), the production of which is possible and limited. And the wealth that exists indefinitely: no economic relations are formed in the production and distribution of solar energy, air, and the like. This current book is the second complete updated edition of the challenges of the modern global economy in the context of the coronary crisis, taking into account some of the priority directions of the country's development. Its purpose is to help students and interested readers gain a thorough knowledge of economics and show them how this knowledge can be applied pragmatically (professionally) in professional activities or in everyday life. To achieve this goal, this textbook, which consists of two parts and tests, discusses in simple and clear language issues such as: the essence of economics as a science, reasons for origin, purpose, tasks, usefulness and functions; Basic principles, problems and peculiarities of economics in different economic systems; Needs and demand, the essence of economic resources, types and limitations; Interaction, mobility, interchangeability and efficient use of economic resources. The essence and types of wealth; The essence, types and models of the economic system; The interaction of households and firms in the market of resources and products; Market mechanism and its elements - demand, supply and price; Demand and supply elasticity; Production costs and the ways to reduce them; Forms of the market - perfect and incomplete competition markets and their peculiarities; Markets for Production Factors and factor incomes; The essence of macroeconomics, causes and importance of origin; The essence and calculation of key macroeconomic indicators (gross national product, gross domestic product, net national product, national income, etc.); Macroeconomic stability and instability, unemployment, inflation and anti-inflationary policies; State regulation of the economy and economic policy; Monetary and fiscal policy; Income and standard of living; Economic Growth; The Corona Pandemic as a Defect and Effect of Globalization; National Economic Problems and New Opportunities for Development in the conditions of the Coronary Crisis; The Socio-economic problems of moral obsolescence in digital technologies; Education and creativity are the main solution way to overcome the economic crisis caused by the coronavirus; Positive and negative effects of tourism in Georgia; Formation of the middle class as a contributing factor to the development of tourism in Georgia; Corporate culture in Georgian travel companies, etc. The axiomatic truth is that economics is the union of people in constant interaction. Given that the behavior of the economy reflects the behavior of the people who make up the economy, after clarifying the essence of the economy, we move on to the analysis of the four principles of individual decision-making. Furtermore, the book describes how people make independent decisions. The key to making an individual decision is that people have to choose from alternative options, that the value of any action is measured by the value of what must be given or what must be given up to get something, that the rational, smart people make decisions based on the comparison of the marginal costs and marginal returns (benefits), and that people behave accordingly to stimuli. Afterwards, the need for human interaction is then analyzed and substantiated. If a person is isolated, he will have to take care of his own food, clothes, shoes, his own house and so on. In the case of such a closed economy and universalization of labor, firstly, its productivity will be low and, secondly, it will be able to consume only what it produces. It is clear that human productivity will be higher and more profitable as a result of labor specialization and the opportunity to trade with others. Indeed, trade allows each person to specialize, to engage in the activities that are most successful, be it agriculture, sewing or construction, and to buy more diverse goods and services from others at a relatively lower price. The key to such human interactions is that trade is mutually beneficial; That markets are usually the good means of coordination between people and that the government can improve the results of market functioning if the market reveals weakness or the results of market functioning are not fair. Moroever, it also shows how the economy works as a whole. In particular, it is argued that productivity is a key determinant of living standards, that an increase in the money supply is a major source of inflation, and that one of the main impediments to avoiding inflation is the existence of an alternative between inflation and unemployment in the short term, that the inflation decrease causes the temporary decline in unemployement and vice versa. The Understanding creatively of all above mentioned issues, we think, will help the reader to develop market economy-appropriate thinking and rational economic-commercial-financial behaviors, to be more competitive in the domestic and international labor markets, and thus to ensure both their own prosperity and the functioning of the country's economy. How he/she copes with the tasks, it is up to the individual reader to decide. At the same time, we will receive all the smart useful advices with a sense of gratitude and will take it into account in the further work. We also would like to thank the editor and reviewers of the books. Finally, there are many things changing, so it is very important to realize that the XXI century has come: 1. The century of the new economy; 2. Age of Knowledge; 3. Age of Information and economic activities are changing in term of innovations. 1. Why is the 21st century the century of the new economy? Because for this period the economic resources, especially non-productive, non-recoverable ones (oil, natural gas, coal, etc.) are becoming increasingly limited. According to the World Energy Council, there are currently 43 years of gas and oil reserves left in the world (see “New Commersant 2007 # 2, p. 16). Under such conditions, sustainable growth of real gross domestic product (GDP) and maximum satisfaction of uncertain needs should be achieved not through the use of more land, labor and capital (extensification), but through more efficient use of available resources (intensification) or innovative economy. And economics, as it was said, is the science of finding the ways about the more effective usage of the limited resources. At the same time, with the sustainable growth and development of the economy, the present needs must be met in a way that does not deprive future generations of the opportunity to meet their needs; 2. Why is the 21st century the age of knowledge? Because in a modern economy, it is not land (natural resources), labor and capital that is crucial, but knowledge. Modern production, its factors and products are not time-consuming and capital-intensive, but science-intensive, knowledge-intensive. The good example of this is a Japanese enterprise (firm) where the production process is going on but people are almost invisible, also, the result of such production (Japanese product) is a miniature or a sample of how to get the maximum result at the lowest cost; 3. Why is the 21st century the age of information? Because the efficient functioning of the modern economy, the effective organization of the material and personal factors of production largely depend on the right governance decision. The right governance decision requires prompt and accurate information. Gone are the days when the main means of transport was a sailing ship, the main form of data processing was pencil and paper, and the main means of transmitting information was sending letters through a postman on horseback. By the modern transport infrastructure (highways, railways, ships, regular domestic and international flights, oil and gas pipelines, etc.), the movement of goods, services and labor resoucres has been significantly accelerated, while through the modern means of communication (mobile phone, internet, other) the information is spreading rapidly globally, which seems to have "shrunk" the world and made it a single large country. The Authors of the book: Ushangi Samadashvili, Doctor of Economic Sciences, Associate Professor of Ivane Javakhishvili Tbilisi State University - Introduction, Chapters - 1, 2, 3, 4, 5, 6, 9, 10, 11,12, 15,16, 17.1,18 , Tests, Revaz Shengelia, Doctor of Economics, Professor of Georgian Technical University, Chapters_7, 8, 13. 14, 17.2, 17.4; Zhuzhuna Tsiklauri - Doctor of Economics, Professor of Georgian Technical University - Chapters 13.6, 13.7,17.2, 17.3, 18. We also thank the editor and reviewers of the book.
Частини книг з теми "Instability constant"
1
Pauly, Ralf. "A Review of the History of the Economy and Its Concepts: Change Is a Constant." In Economic Instability and Stabilization Policy, 31–93. Wiesbaden: Springer Fachmedien Wiesbaden, 2021. http://dx.doi.org/10.1007/978-3-658-33626-4_2.
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Alipour, M. J., and A. Lashkari. "Prediction of Sand Instability Under Constant Shear Drained Paths." In Springer Series in Geomechanics and Geoengineering, 105–10. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-56397-8_13.
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Tiwari, Udit, and Sahab Dass. "Moisture Stable Soot Coated Methylammonium Lead Iodide Perovskite Photoelectrodes for Hydrogen Production in Water." In Springer Proceedings in Energy, 141–48. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-63916-7_18.
Повний текст джерелаАнотація:
AbstractMetal halide perovskites have triggered a quantum leap in the photovoltaic technology marked by a humongous improvement in the device performance in a matter of just a few years. Despite their promising optoelectronic properties, their use in the photovoltaic sector remains restricted due to their inherent instability towards moisture. Here, we report a simple, cost-effective and highly efficient protection strategy that enables their use as photoelectrodes for photoelectrochemical hydrogen production while being immersed in water. A uniform coating of candle soot and silica is developed as an efficient hydrophobic coating that protects the perovskite from water while allowing the photogenerated electrons to reach the counter electrode. We achieve remarkable stability with photocurrent density above 1.5 mA cm−2 at 1 V versus saturated calomel electrode (SCE) for ~1 h under constant illumination. These results indicate an efficient route for the development of stable perovskite photoelectrodes for solar water splitting.
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Vahid-Araghi, Orang, and Farid Golnaraghi. "Kinematic Constraint Instability Mechanism." In Friction-Induced Vibration in Lead Screw Drives, 135–56. New York, NY: Springer New York, 2010. http://dx.doi.org/10.1007/978-1-4419-1752-2_8.
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Epstein, Gerald A. "The Mystery of the Missing Minsky: Financial Instability as a Constraint on MMT Macroeconomic Policy." In What's Wrong with Modern Money Theory?, 65–75. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-26504-5_6.
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Alboiu, Gabriela, and Virginia Hill. "Diachronic change and feature instability." In Syntactic Features and the Limits of Syntactic Change, 64–83. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198832584.003.0004.
Повний текст джерелаАнотація:
This chapter focuses on diachronic changes of obligatory control (OC) constructions in Romanian. We argue that the setting for the OC parameter has remained constant since the 16th century, but that the values of the features associated with the C/T/Agr system show systematic change. Specifically, Romanian OC follows the Balkan paradigm (i.e., truncated/FinP clause) which is under tension to accommodate the Romance morphology with Force features that it employs. This pressure results in a continuous cycle, from syncretic to split and, again, to remerged C. This process affects Fin, the only C head available to Romanian OC, alongside constant flux of the T/Agr specifications (i.e., inflected versus uninflected). These findings support the Borer-Chomsky Conjecture (BCC) that sees variation as being restricted to formal features of functional heads (Baker 2008), namely, [+/- Agr] of C/T, while aligning with Biberauer and Walkden’s (2015) observation that diachronic syntax has shifted from the “macro” to the “micro” level.
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Gouveia, José António Velho. "Safety and Security as Premises for the Competitiveness of Coastal and Maritime Tourism." In Managing, Marketing, and Maintaining Maritime and Coastal Tourism, 33–51. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-1522-8.ch003.
Повний текст джерелаАнотація:
The multiple aspects of safety and security of people have always deserved the highest importance in human society. Today, the world faces huge, general instability with constant global risks and threats in daily life. Instability and insecurity jeopardize the economy and social relations at all levels. Those involved in economic activities like tourism have always understood safety and security are essential conditions for development. Coastal and maritime tourism are very vulnerable. This chapter covers the safety and security of the tourist in activities he can perform in coastal and maritime territories and the risks and threats he can face there. Authors present a Portuguese situation on the subject, and give ideas to minimize insecurity from both points of view (safety and security) in coastal and maritime tourism.
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Wani, Aijaz Ashraf. "Conclusion." In What Happened to Governance in Kashmir?, 345–56. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780199487608.003.0007.
Повний текст джерелаАнотація:
Governance is the function of a cluster of factors. The priorities of governance and their hierarchical order vary from place to place, depending on specific contexts. Jammu and Kashmir is a conflicted state with both exogenous and endogenous dimensions. There is a dispute over Kashmir, a dispute with the centre, and the dispute among the regions of the state. All cumulatively create permanent instability in Kashmir. The conflict began with the Partition and it continues to stay. In July 1952, Nehru stated in the Indian Parliament, ‘If you go to Kashmir you will find normalcy and that the state is functioning adequately; but behind this normalcy is the constant tension because of the enemy trying to come in to create trouble and disturb.’...
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Kafi, Farhad, and Majid Kafi. "Information Quality in Supply Chain Software." In Handbook of Research on Global Supply Chain Management, 105–26. IGI Global, 2016. http://dx.doi.org/10.4018/978-1-4666-9639-6.ch006.
Повний текст джерелаАнотація:
In the new dynamic economic environment where supply chains increasingly face constant change and instability, the better supply chain planning and management enabled by advanced data management systems provides enhanced value proposition for customers resulting in improved profitability for firms along the supply chain. However, achieving such high quality level of supply chain visibility is not an easy task requiring technological capability, organizational willingness and data quality management intensively demanding attention from both managers and scholars. Therefore, the chapter begins with an overview of the role of information systems in supply chain management followed by a discussion regarding the role of information quality in successful supply chain interactions. Data quality management in terms of strategy and data governance is then reviewed. Finally, data quality tools complementing strategy dimension of data quality management are studied.
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Velasco, Diana Carolina, and Sergio Pulgarín. "Developing Innovation Using Entrepreneurial Strategies." In Evolving Entrepreneurial Strategies for Self-Sustainability in Vulnerable American Communities, 207–30. IGI Global, 2018. http://dx.doi.org/10.4018/978-1-5225-2860-9.ch011.
Повний текст джерелаАнотація:
This chapter analyzes the entrepreneurial strategies that Colombian coffee growers develop in order to deal with adverse social, economic, and environmental conditions. These entrepreneurs are part of a long and rich heritage dating as far back as the end of the 19th century, when coffee became an important economic resource in Colombia. Constant variations, including coffee price volatility, instability of exchange rates, or environmental factors, such as climatic change and crop disease, are common conditions for coffee farmers. In order to survive during turbulent environments, coffee growers have adopted strategies such as the introduction of new services and final products; improvements in the production chain; horizontal and vertical cooperation; creativity and flexibility in order to be resilient to the changing market conditions. More than 560,000 vulnerable families in Colombia depend on coffee production as a main source of income, so studies to help strengthen their business are highly relevant.
Тези доповідей конференцій з теми "Instability constant"
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S.I., Ikram Khan, Yusuf Panbiharwala, B. Srinivasan, and A. Prabhakar. "Detection of Fibre Laser Instability Using a Constant Fraction Discriminator." In 2017 IEEE Workshop on Recent Advances in Photonics (WRAP). IEEE, 2017. http://dx.doi.org/10.1109/wrap.2017.8468541.
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Ahmed, A., Li Ran, and J. R. Dumby. "Stalling region instability compensation for constant power soft stalling control." In 5th IET International Conference on Power Electronics, Machines and Drives (PEMD 2010). Institution of Engineering and Technology, 2010. http://dx.doi.org/10.1049/cp.2010.0044.
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Primavera, Leonardo, and Günther Rüdiger. "Magnetic shear instability for accretion tori of constant specific angular momentum." In Accretion processes in astrophysical systems: Some like it hot! - eigth astrophysics conference. AIP, 1998. http://dx.doi.org/10.1063/1.55944.
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Moussa, Sonia, Manel Jebali-Ben Ghorbal, Ilhem Slama-Belkhodja, Jean-Philippe Martin, and Serge Pierfederici. "DC bus voltage instability detection and stabilization under constant power load variation." In 2018 9th International Renewable Energy Congress (IREC). IEEE, 2018. http://dx.doi.org/10.1109/irec.2018.8362518.
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Sahay, C., and R. N. Dubey. "On Tool Instability During Machining." In ASME 1991 Design Technical Conferences. American Society of Mechanical Engineers, 1991. http://dx.doi.org/10.1115/detc1991-0335.
Повний текст джерелаАнотація:
Abstract The present paper describes the role of the tool in vibrations of a machining system. The cutting force has been assumed to be constant. The shear deformation of the tool is considered. The quasi-static analysis of the situation yields a maximum allowable uncut chip thickness, which shows how the frictional interaction at the tool face and the ratio of the components of cutting forces alter this value. The relationship also expresses the effect of tool dimensions and work material on the vibration of the tool.
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Lee, Hee Joon, and Shi-Chune Yao. "System Instability of Evaporative Micro-Channels." In ASME 2009 Heat Transfer Summer Conference collocated with the InterPACK09 and 3rd Energy Sustainability Conferences. ASMEDC, 2009. http://dx.doi.org/10.1115/ht2009-88217.
Повний текст джерелаАнотація:
During the operation of parallel evaporative micro-channels, system instability may occur in terms of cyclical fluctuations at a long period. This is due to the co-existence of the liquid phase flow at high mass flux and the two-phase flow at a lower mass flux among different parallel channels under the same total pressure drop. For a system at constant flow-rate pumping, with a pressure regulating tank, and a constant heating pre-heater, the system may experience severe alternations between these two states of boiling and non-boiling with a period of minutes. This cyclical system instability has been modeled. In the model, the existence of the liquid phase flow happens at conditions of inlet subcooling and low surface heat flux that the boiling inception is hard to occur. Accordingly, the system instability criteria are established in terms of a System binary states parameter S and a non-dimensional surface heat flux, which is normalized with the boiling incipient heat flux. This model has been validated experimentally.
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Nanua, Prabjot, and Kenneth J. Waldron. "Instability and Chaos in Quadruped Gallop." In ASME 1992 Design Technical Conferences. American Society of Mechanical Engineers, 1992. http://dx.doi.org/10.1115/detc1992-0264.
Повний текст джерелаАнотація:
Abstract A dynamic model for the two dimensional quadruped has been developed. The main body is modelled as a rigid bar and each leg consists of a constant stiffness spring, a viscous damper and a force actuator. Based on symmetry principles, a controller has been devised that will enable the quadruped to gallop at constant speed. The controller consists of two parts: an energy controller which will apply the required amount of force through the legs, and the speed controller that will control the forward speed by appropriately placing the legs. It will be shown that the body pitch need not be explicitly controlled. The stability of this controller will be examined using Poincare maps. Stable systems show either periodic or quasi-periodic response. This system also exhibits chaotic behavior and chaotic response leads to instability. The stability of the system with changes in the initial conditions, as well as variations in the system parameters, will also be examined. It will be shown that the system is stable for a range of leg stiffnesses. Outside this range, the system shows chaotic behavior.
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Vilathgamuwa, D. M., X. N. Zhang, S. D. G. Jayasinghe, B. S. Bhangu, C. J. Gajanayake, and King Jet Tseng. "Virtual resistance based active damping solution for constant power instability in AC microgrids." In IECON 2011 - 37th Annual Conference of IEEE Industrial Electronics. IEEE, 2011. http://dx.doi.org/10.1109/iecon.2011.6119901.
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Wong, G. K. L. "Using modulation instability to determine the propagation constant in a photonic crystal fibre." In 31st European Conference on Optical Communications (ECOC 2005). IEE, 2005. http://dx.doi.org/10.1049/cp:20050422.
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Malviya, P. S., and N. Yadav. "Colloidal effects on modulational instability in semiconductor plasma having strain dependent dielectric constant." In EMERGING INTERFACES OF PHYSICAL SCIENCES AND TECHNOLOGY 2019: EIPT2019. AIP Publishing, 2020. http://dx.doi.org/10.1063/5.0000472.
Повний текст джерелаЗвіти організацій з теми "Instability constant"
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Alexander, S. The Gravitational Instability of the Vacuum: Insight into the Cosmological Constant Problem. Office of Scientific and Technical Information (OSTI), July 2004. http://dx.doi.org/10.2172/827296.
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Soloviev, V. N., and Y. V. Romanenko. Economic analog of Heisenberg uncertainly principle and financial crisis. ESC "IASA" NTUU "Igor Sikorsky Kyiv Polytechnic Institute", May 2017. http://dx.doi.org/10.31812/0564/2463.
Повний текст джерелаАнотація:
The Heisenberg uncertainty principle is one of the cornerstones of quantum mechanics. The modern version of the uncertainty principle, deals not with the precision of a measurement and the disturbance it introduces, but with the intrinsic uncertainty any quantum state must possess, regardless of what measurement is performed. Recently, the study of uncertainty relations in general has been a topic of growing interest, specifically in the setting of quantum information and quantum cryptography, where it is fundamental to the security of certain protocols. The aim of this study is to analyze the concepts and fundamental physical constants in terms of achievements of modern theoretical physics, they search for adequate and useful analogues in the socio-economic phenomena and processes, and their possible use in early warning of adverse crisis in financial markets. The instability of global financial systems depending on ordinary and natural disturbances in modern markets and highly undesirable financial crises are the evidence of methodological crisis in modelling, predicting and interpretation of current socio-economic conditions.