Oscillation criteria for second order nonlinear perturbed differential equations

Sufficient conditions for the oscillation of the nonlinear second order differential equation $(a(t)x^{\prime })^{\prime }+Q(t,x^{\prime})=P(t,x,x^{\prime })$ are established where the coefficients are continuous and $a(t)$ is nonnegative

Ultimate boundedness and periodicity results for a certain system Of third-order nonlinear Vector delay differential equations

In the last years, there has been increasing interest in obtaining the sufficient conditions for stability, instability, boundedness, ultimately boundedness, convergence, etc. For instance, in applied sciences some practical problems concerning mechanics, engineering technique fields, economy, control theory, physical sciences and so on are associated with third, fourth and higher order nonlinear differential equations. The problem of the boundedness and stability of solutions of vector differential equations has been widely studied by many authors, who have provided many techniques especially for delay differential equations. In this work a class of third order nonlinear non-autonomous vector delay differential equations is considered by employing the direct technique of Lyapunov as basic tool, where a complete Lyapunov functional is constructed and used to obtain sufficient conditions that guarantee existence of solutions that are periodic, uniformly asymptotically stable, uniformly ultimately bounded and the behavior of solutions at infinity. In addition to being for a more general equation, the obtained results here are new even when our equation is specialized to the forms previously studied and include many recent results in the literature. Finally, an example is given to show the feasibility of our results

On stability, boundedness, and square integrability of solutions of certain third order neutral differential equations

summary:The authors establish some new sufficient conditions under which all solutions of a certain class of nonlinear neutral delay differential equations of the third order are stable, bounded, and square integrable. Illustrative examples are given to demonstrate the main results

On the stability, boundedness, and square integrability of solutions of third order neutral delay differential equations

In this paper, sufficient conditions are established for the stability, boundedness and square integrability of solutions for some non-linear neutral delay differential equations of third order. Lyapunov’s direct method is used to obtain the results

Caracteriza??o f?sico-qu?mica e perfil sensorial de m?is de abelhas nativas, sem ferr?o, oriundas da regi?o centro-sul do estado do Paran?, Brasil

The objective of this study was to perform the physico-chemical and microbiological characterization. In addition, was evaluated the sensory profile of three honeys of native stingless bees Tetragonisca angustula, Melipona quadrifasciata quadrifasciata, and Scaptotrigona posti?a, obtained in the Central-Southern region of the State of Paran?, were evaluated in order to compare the characteristics among the species. Seven samples were characterized by analysis of water activity, moisture, pH, titratable total acidity, color, total soluble solids -SST- (?Brix), total phenolic compounds, hydroxymethylfurfural (HMF) and chemical elements. The honeys of Tetragonisca angustula have been shown to have singularities in their composition, differing from the other evaluated species. These honeys have lower water content (21.07 to 22.40%) and lower concentrations of total acidity (38-75 mEq / kg). The honeys of the species Tetragonisca angustula were considered light to dark amber, while the species Melipona quadrifasciata quadrifasciata, and Scaptotrigona postigo, were classified as extra light amber color and colorations close to yellow. For TSS, the species Tetragonisca angustula presented higher concentrations (75.93 to 77.17) and the same was observed for total phenolic compounds (18.30 to 39.60 mg AG / 100 g). Nineteen chemical elements were quantified, with the major components: K, Na, P, Ca and Mg, in all samples. The microbiological evaluation was carried out through determinations of molds and yeasts, total coliforms and thermotolerant coliforms, and demonstrated that honeys are suitable for immediate consumption. All samples of stingless bee honeys diverged from honey identity and quality standards. Honey from stingless bees has unique characteristics of A. mellifera, requiring specific regulation of stingless bee species. In the results of the sensory analysis, the sample 4 (Tetragonisca angustula) presented the most significant differences in the acceptance test, for all evaluated attributes (aroma, appearance, color, flavor and texture), presenting averages above 7.0, representing a positive assessment. Sample 7 (Melipona q. quadrifasciata) was rejected by the tasters, as it showed lower averages for flavor and texture, 4.0 and 5.0, respectively. By means of purchase intention, Sample 4 (Tetragonisca angustula) was the most accepted by the tasters. Thus, the species Tetragonisca angustula differs in its physico-chemical characteristics interfering in the sensory parameters and, consequently, resulting in the sensory approval before the judges. This demonstrated that the physico-chemical characteristics can aid in the choice of sensorial preference of honeys. Finally, the research contributed to the observation that consumers prefer sweet honeys of lower acidity, with viscous texture and dark coloring.O objetivo deste estudo foi realizar a caracteriza??o f?sico-qu?mica e microbiol?gica, al?m disso foi avaliado o perfil sensorial de tr?s m?is de abelhas nativas sem ferr?o Tetragonisca angustula, Melipona quadrifasciata quadrifasciata, e Scaptotrigona posti?a, obtidos na regi?o Centro-Sul do Estado do Paran?, a fim de comparar as caracter?sticas entre as esp?cies. Sete amostras foram caracterizadas por meio das an?lises de atividade de ?gua, umidade, pH, acidez total titul?vel, cor, S?lidos Sol?veis Totais -SST- (?Brix), compostos fen?licos totais, hidroximetilfurfural (HMF) e elementos qu?micos. Os m?is de Tetragonisca angustula demonstraram ter singularidades em sua composi??o, diferindo-se das demais esp?cies avaliadas. Esses m?is possuem menor conte?do de ?gua (21,07 a 22,40%) e concentra??es inferiores de acidez total (38-75 mEq/Kg). Os m?is da esp?cie Tetragonisca angustula foram considerados com colora??o ?mbar-claro a escuro, enquanto as esp?cies Melipona quadrifasciata quadrifasciata, e Scaptotrigona posti?a, foram classificadas com cor extra ?mbar claro e colora??es pr?ximas ao amarelo. Para SST, a esp?cie Tetragonisca angustula apresentou maiores concentra??es (75,93-77,17) e o mesmo foi observado para os compostos fen?licos totais (18,30-39,60 mg AG/100 g). Dezenove elementos qu?micos foram quantificados, sendo os componentes majorit?rios: K, Na, P, Ca e Mg, em todas as amostras. A avalia??o microbiol?gica foi desenvolvida atrav?s das determina??es de bolores e leveduras, coliformes totais e coliformes termotolerantes, e demonstraram que os m?is s?o aptos para o consumo imediato. Todas as amostras de m?is de abelhas sem ferr?o divergiram dos padr?es de identidade e qualidade do mel. O mel de abelhas sem ferr?o possui caracter?sticas singulares das A. mellifera, sendo necess?ria uma regulamenta??o espec?fica ?s esp?cies de abelhas sem ferr?o. Nos resultados da an?lise sensorial, a amostra 4 (Tetragonisca angustula) foi a que mais apresentou diferen?as significativas no teste de aceita??o, para todos os atributos avaliados (aroma, apar?ncia, cor, sabor e textura), apresentando m?dias acima de 7,0, representando uma avalia??o positiva. A amostra 7 (Melipona q. quadrifasciata) foi rejeitada pelos provadores, pois exibiu m?dias inferiores para sabor e textura, 4,0 e 5,0, respectivamente. Por meio da inten??o de compra, a amostra 4 (Tetragonisca angustula) foi a mais aceita pelos provadores. Deste modo, a esp?cie Tetragonisca angustula se difere em suas caracter?sticas f?sico-qu?micas interferindo nos par?metros sensorias e, consequentemente, resultando na aprova??o sensorial perante os julgadores. Isso demonstrou que as caracter?sticas f?sico-qu?micas podem auxiliar na escolha de prefer?ncia sensorial de m?is. Por fim, a pesquisa contribuiu para observar que os consumidores preferem m?is doces de menor acidez, com textura viscosa e de colora??o escura

Le comportement stratégique face à une rupture institutionnelle programmée

L'objectif de cette thèse est de contribuer à une meilleure compréhension de la formulation et du renouvellement des stratégies à travers le temps. Nous avons pour ce faire choisi d'analyser les comportements stratégiques de trois entreprises face à un choc prévisible annoncé plusieurs années d'avance. Il s'agit de l'abolition des quotas à l'importation de vêtements décidée par l'Organisation Mondiale du Commerce en 1995, et qui devait prendre effet en 2005. La recherche a porté sur les deux questions suivantes : • Quels sont les facteurs qui peuvent nous aider à comprendre la réaction et le comportement d'une entreprise à la suite d'une rupture institutionnelle programmée? • Existe-t-il des régularités qui se dégagent de l'évolution du processus stratégique prenant place à la suite d'une rupture institutionnelle programmée? La recherche est exploratoire et qualitative. Elle a été guidée par un modèle interactif de type contextualiste construit à partir de la littérature, qui met en relation trois éléments centraux : la création de sens par les décideurs, le contexte de chaque entreprise et les ressources relationnelles liant les entreprises et leurs parties prenantes. Ce modèle est globalement validé par le terrain. Il nous a permis, d'une part, de saisir les logiques sous-jacentes aux réponses formulées par les entreprises face à la rupture annoncée et, d'autre part, de replacer ces logiques dans l'évolution générale de la stratégie de ces entreprises à travers le temps. L'analyse de nos résultats nous a révélé l'existence d'une forte cohérence entre les différents éléments de réponse aux questions posées. Nous proposons de les intégrer dans un modèle centré sur le concept de « maturité stratégique », défini comme l'acquisition par une entreprise de l'expertise nécessaire à la construction et au renouvellement de sa vision et de son action stratégiques. La maturité stratégique est faite à la fois de clairvoyance proactive et de capacité d'action. Elle s'enrichit dans le temps au cours d'un processus collectif d'apprentissage au contact des différentes problématiques internes et externes auxquelles les dirigeants sont appelés à se mesurer. La maturité stratégique expliquerait ainsi pourquoi les entreprises d'une même industrie ont su profiter mieux que d'autres du délai de dix ans dont elles disposaient avant l'abolition définitive des quotas à l'importation.\ud ______________________________________________________________________________ \ud MOTS-CLÉS DE L’AUTEUR : formation des stratégies, rupture institutionnelle programmée, dirigeant, contexte, ressources relationnelles, création de sens, industrie du vêtement, abolition des quotas

Boundedness and Square Integrability in Neutral Differential Systems of Fourth Order

The aim of this paper is to study the asymptotic behavior of solutions to a class of fourth-order neutral differential equations. We discuss the stability, boundedness and square integrability of solutions for the considered system. The technique of proofs involves defining an appropriate Lyapunov functional. Our results obtained in this work improve and extend some existing well-known related results in the relevant literature which were obtained for nonlinear differential equations of fourth order with a constant delay. The obtained results here are new even when our equation is specialized to the forms previously studied and include many recent results in the literature. Finally, an example is given to show the feasibility of our results

Roma Cezayiri’nin Dionysiak döşemeleri üzerindeki ifadeler ve duygular

The figurative ancient mosaics often represent “living” paintings which depict mythological, historical or real personages who manage to express various feelings thanks to the ingenuity of the mosaic craftsmen. Indeed, the art of ancient mosaic has not ceased to evolve since the Hellenistic period in the direction of the translation of the emotions and feelings that give life to the myths and legends represented. The mosaics which decorated the ceremonial and reception rooms in luxurious domus did not only play an ornamental role, they entertained the guests, stimulated all their senses and provoked the exchange of conversations around the table. The Dionysian mosaics were particularly intended for this function because Dionysus is the god of the banquet! By admiring some of the many pavements of the Dionysian legend of Roman Algeria, one can detect the rendering of emotions and soak up an unreal and almost real atmosphere at the same time! ... This article is an invitation to discover a whole range of sometimes contradictory feelings that appear on mosaics; we will thus be able to see how the African mosaicists from the end of the 2nd to the 5th century A.D. used various methods to make their personages more expressive and alive.Figüratif antik mozaikler, mozaik ustalarının hünerleri sayesinde çeşitli duygularını ifade etmeyi başaran mitolojik, tarihi veya gerçek kişilikleri betimleyen “canlı” resimleri sıklıkla temsil etmektedir. Nitekim antik mozaik sanatı, temsil edilen mit ve efsanelere hayat veren duygu ve hislerin tercümesi doğrultusunda Helenistik Dönem’den bu yana gelişmeyi bırakmamıştır. Lüks domustaki tören ve kabul odalarını süsleyen mozaikler, sadece bir dekorasyon görevi üstlenmemiş, misafirleri eğlendirmiş, tüm duyuları harekete geçirmiş ve masa etrafında karşılıklı sohbetlerin yaşanmasına neden olmuştur. Dionysos mozaikleri özellikle bu işlev için tasarlanmıştır çünkü Dionysos ziyafetin tanrısıdır! Roma Cezayiri’nin Dionysos efsanesinin birçok döşemeden bazılarına hayran kalınarak, duyguların yorumlanması algılanabilir ve aynı anda hem gerçek dışı hem de neredeyse gerçek bir atmosfer kişiyi içine çekebilir! ... Bu makale, mozaiklerde ortaya çıkan, bazen birbiriyle çelişen bir dizi duyguyu keşfetmeye bir davettir; 2. yüzyılın sonundan 5. yüzyıla kadar Afrikalı mozaik ustalarının kişiliklerini daha etkileyici ve canlı kılmak için çeşitli yöntemler kullandıklarını böylece görebiliriz