999 resultados para base di trascendenza disgiunzione lineare estensione separabile base di trascendenza campo perfetto


Relevância:

40.00% 40.00%

Publicador:

Resumo:

This study was undertaken to evaluate the suitability of various stones which play an important role in the properties of compacted mixtures in asphalt treated bases. The determination of the effect of water temperature on the cohesion of the mixes is investigated. A number of stones were prepared for the test. Attention is paid to the particular source of stone with the corresponding test results. A preliminary study of the effect of lime when added to mixed aggregate was also conducted. The purpose of this study is to provide needed information on the cohesive characteristics of asphalt treated bases using a wide range of stones. This study is also to evaluate the suitability of the various stone sources.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

In recent years, it has become apparent that the design and maintenance of pavement drainage extends the service life of pavements. Most pavement structures now incorporate subsurface layers. Part of the function of these subsurface layers is to drain away excess water, which can be extremely deleterious to the life of the pavement. To assure the effectiveness of such drainage layers after they have been spread and compacted, simple, rapid, in-situ permeability and stability testing and end-result specification are needed. This report includes conclusions and recommendations related to four main study objectives: (1) Determine the optimal range for in-place stability and in-place permeability based on Iowa aggregate sources; (2) Evaluate the feasibility of an air permeameter for determining the permeability of open and well-graded drainage layers in situ; (3) Develop reliable end-result quality control/quality assurance specifications for stability and permeability; and (4) Refine aggregate placement and construction methods to optimize uniformity.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

The problems of laboratory compaction procedures, the effect of gradation and mineralogy on shearing strength, and effect of stabilizing agents on shearing strength of granular base course mixes are discussed. For the materials tested, a suitable laboratory compaction procedure was developed which involves the use of a vibratory table to prepare triaxial test specimens. A computer program has been developed to facilitate the analysis of the test data of the effect of gradation and mineralogy on shearing strength of soils. The effects of the following materials have been selected for evaluation as stabilizing agents’ portland cement, sodium and calcium chloride, lime organic cationic waterproofer, and asphaltic materials.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

The problems of laboratory compaction procedures, the effect of gradation and mineralogy on shearing strength, and effect of stabilizing agents on shearing strength of granular base course mixes are discussed. For the materials tested, a suitable laboratory compaction procedure was developed which involves the use of a vibratory table to prepare triaxial test specimens. A computer program has been developed to facilitate the analysis of the test data of the effect of gradation and mineralogy on shearing strength of soils. The effects of the following materials have been selected for evaluation as stabilizing agents’ portland cement, sodium and calcium chloride, lime organic cationic waterproofer, and asphaltic materials.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

The problems of laboratory compaction procedures, the effect of gradation and mineralogy on shearing strength, and effect of stabilizing agents on shearing strength of granular base course mixes are discussed. For the materials tested, a suitable laboratory compaction procedure was developed which involves the use of a vibratory table to prepare triaxial test specimens. A computer program has been developed to facilitate the analysis of the test data of the effect of gradation and mineralogy on shearing strength of soils. The effects of the following materials have been selected for evaluation as stabilizing agents’ portland cement, sodium and calcium chloride, lime organic cationic waterproofer, and asphaltic materials.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Results are presented of triaxial testing of three crushed limestones to which either hydrated high-calcium lime, sodium chloride or calcium chloride had been added. Lime was added at rates of 1, 3, 10 and 16 percent, chlorides were added at 0.5 percent rate only. Speciments were compacted using vibratory compaction apparatus and were tested in triaxial compression using lateral pressures from 10 to 100 psi. Triaxial test results indicate that: (1) sodium chloride slightly decreased the angle of internal friction and increased cohesion, (2) calcium chloride slightly increased the angle of internal friction and decreased cohesion, and (3) lime had no appreciable effect on angle of internal friction but increased cohesion, decreased density and increased pore water pressure.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

A highway base course may be defined as a layer of granular material which lies immediately below the wearing surface of a pavement and must possess high resistance to deformation in order to withstand pressures imposed by traffic. A material commonly used for base course construction is crushed limestone. Sources of limestone, acceptable for highway bases in the state of Iowa, occur almost entirely in the Pennsylvanian, Mississippian and Devonian strata. Performance records of the latter two have been quite good, while material from the Pennsylvanian stratum has failed on numerous occasions. The study reported herein is one segment of an extensive research program on compacted crushed limestone used for flexible highway base courses. The primary goals of the total study are: 1. Determination of a suitable and realistic laboratory method of compaction. 2. Effect of gradation, and mineralogy of the fines, on shearing strength. 3. Possible improvement of the shear strength with organic and inorganic chemical stabilization additives. Although the study reported herein deals primarily with the third goal, information gathered from work on the first two was required for this investigation. The primary goal of this study was the evaluation of various factors of stability of three crushed limestones when treated with small amounts of type I Portland cement. Investigation of the untreated materials has indicated that shear strength alone is not the controlling factor for stability of crushed stone bases. Thus the following observations were made in addition to shear strength parameters, to more adequately ascertain the stability of the cement treated materials: 1. Volume change during consolidation and shear testing. 2. Pore pressure during shear. The consolidated-undrained triaxial shear test was used for determination of the above factors.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Letterato versatile e curioso del presente, Sertorio Quattromani (Cosenza 1541-1603) fu uno dei migliori critici letterari della seconda metà del Cinquecento, come dimostrano innanzi tutto l'importante esposizione delle Rime di Della Casa (edita postuma nel 1616) e ora il commento alle Rime di Bembo, qui per la prima volta pubblicato, sulla base del manoscritto Palatino 1036 della Biblioteca Nazionale Centrale di Firenze, nel quale si conserva adespoto con il titolo Luoghi difficili del Bembo. Elaborato tra il 1564 e il 1570, il commento bembiano si presenta non del tutto compiuto, per quanto già ricco di chiose esplicative e di riferimenti intertestuali. Occorre tuttavia considerare che la tipologia esegetica scelta da Quattromani non è quella dell'esposizione continua ma quella del commento tecnico e selettivo, incentrato sulla spiegazione dei luoghi difficili e sull'allegazione dei loci paralleli, oltre che sulle censure di gusto e sui rilievi linguistici, stilistici e retorici. Focalizzata sulla parafrasi e sull'intertestualità, l'annotazione di Quattromani intende essere al servizio del testo e insieme offrire agli scrittori coevi la possibilità di entrare in uno dei più raffinati laboratori poetici del Rinascimento. Almeno due sono le ragioni per motivare il recupero di un'opera incompiuta, e che lo stesso autore non ritenne più adeguata ai tempi, impegnandosi nell'esegesi delle Rime dellacasiane. Innanzi tutto un motivo di ordine generale: letture e commenti di critici coevi all'autore sono di grande utilità per un'interpretazione dei testi storicamente fondata. Poi un motivo specifico, che riguarda lo sviluppo della lirica italiana: già da metà Cinquecento l'esegesi dei poeti contemporanei diventa uno strumento essenziale per costruire la lirica moderna sulle fondamenta gettate da Bembo prima e da Della Casa poi. Infatti nel commento bembiano di Quattromani la fitta allegazione di loci paralleli estratti dalla letteratura latina serve anche a rivelare quanto il petrarchismo di Bembo non si alimenti del solo Petrarca. Rispetto alla vulgata petrarchistica, ciò che emerge nel Bembo di Quattromani è pertanto l'impossibilità per un poeta non corrivo di attenersi a norme insensibili al mutare dei tempi. Il riuso del dettato petrarchesco resta ovviamente legge, ma a patto che accolga nuove commistioni e svariati incrementi. In particolare, si avverte come sempre più vitale la riappropriazione profonda di tutta la letteratura in latino, da quella antica a quella umanistico-rinascimentale, tanto da pervenire a una contaminazione di latino e volgare che può essere considerata uno dei principali fattori di apertura della strada verso il Barocco intrapresa a fine Cinquecento dalla poesia italiana.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

A aceroleira (Malpighia emarginata) é uma espécie da família Malpighiaceae que produz frutos com alto conteúdo de vitamina C. O crescimento da demanda da acerola e de seus derivados causou a procura de variedades melhoradas, para expansão dos plantios comerciais. O objetivo deste trabalho foi obter informações sobre o sistema de cruzamento de um pomar de aceroleiras localizado em Visconde do Rio Branco, MG. Dez famílias oriundas de sementes de polinização natural foram genotipadas usando-se sete locos izoenzimáticos (Idh, Mdh-1, Mdh-2, Pgm-1, Pgm-2, Est-1 e Pod), e os dados foram submetidos a análise pelo modelo misto de cruzamento. A estimativa da taxa de cruzamento da população utilizando todos os locos simultaneamente não diferiu estatisticamente de 1,00. Nas famílias, as estimativas variaram de 0,68 a 1,00, e duas diferiram significativamente de 1,00. Conclui-se que a aceroleira é predominantemente alógama e que a taxa de cruzamento varia entre famílias, fato que deve ser levado em consideração em programas de melhoramento e conservação de germoplasma.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Flores de zínia (Zinnia elegans Jacq.) são adaptadas às condições climáticas da Região Sudeste do País, com excelente potencial para a comercialização como flor de corte. O presente trabalho objetivou avaliar a influência da sacarose aplicada na forma de solução de condicionamento, e do corte periódico da base das hastes sobre a longevidade e absorção de água pelas flores. Hastes florais uniformizadas em tamanho foram submetidas ao condicionamento, por seis horas, com sacarose a 5, 10, 15 e 20% ou com soluções de 10% de sacarose por 0, 6, 12, 18 e 24 horas, com ou sem cortes periódicos na base das hastes a cada 48 horas. O tratamento das flores por seis horas com sacarose a 5, 10, 15 ou 20% não afetou a longevidade das flores, comparado àquelas mantidas somente com água destilada. O corte periódico da base das hastes promoveu melhor suprimento de água às flores, estendendo a longevidade. O condicionamento das flores com 10% de sacarose por 18 ou 24 horas acelerou a senescência das flores em vaso. A taxa de produção de etileno foi inibida pelo aumento da concentração de sacarose na solução de condicionamento.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

RESUME : La thèse examine les relations entre le duché de Milan et le Corps helvétique dans l'évolution du système westphalien, à travers l'étude des réformes institutionnelles opérées par les Austro-Lombards sur le territoire milanais au XVIIIe siècle, où le bon voisinage tend à remplacer les traités qui assuraient jusque là les échanges économiques et culturels. L'analyse met en lumière le caractère négocié de ces transformations sur la base de l'étude des pratiques des nouveaux agents issus des milieux militaire et aristocratique. L'étude des anciennes alliances et la permanence de l'héritage espagnol dans ses relations avec le Corps hevétique rendent compte, dans une première partie, des modalités selon lesquelles la raison d'Etat donne à lire la modernité des pratiques austro-lombardes pour intégrer le duché dans la monarchie des Habsbourg. Les trois chapitres suivants saisissent l'impact des réformes qui amorcent une centralisation politique, où le choix des négociateurs milanais reflète la nouvelle situation du duché, dont les tractations frontalières définissent la rationalité du territoire comme limite de l'Autre. Correspondances officielle et privée, mémoires ou autres essais rédigés par les nouvelles élites administratives et diplomatiques milanaises ou viennoises illustrent les modalités selon lesquelles la suppression des anciennes alliances confessionnelles développe un système d'informations politiques pluralistes et sécularisées. Celui-ci se base sur une connaissance politique du voisin helvétique, rapportée par des observateurs mandés comme experts dont la pratique est tributaire des intérêts personnels et de la loyauté envers le monarque. Enfin, les deux dernières parties saisissent la centralité financière et culturelle des villes protestantes suisses, où l'essor bancaire supplante progressivement le système des capitulations militaires mais où les résistances politiques limitent les améliorations en matière de passage ou de sécurité frontalière. L'intense activité éditoriale des centres protestants helvétiques confirme l'attention des élites austro-lombardes sur les modèles d'émancipation économique et culturelle tels que celui de la République de Genève. A la veille d'un nouvel ordre européen, ils rendent compte de l'enchevêtrement des réseaux où émerge une classe de fonctionnaires qui, dans leur mission au service du prince, allient désormais leurs intérêts pour la République des lettres à une volonté de réformer l'Etat.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Isolated avulsion fracture of the peroneus longus tendon insertion at the base of the first metatarsal is very rare. Similar to most avulsion fractures that result from excessive strain at a tendon or ligament insertion, this type of injury is caused by the strong tension exerted by the peroneus longus tendon. The mechanisms leading to this lesion and treatment options are not clearly defined. We present the case of an isolated minimally displaced intra-articular avulsion fracture at the plantar lateral base of the first metatarsal. Faced with a painful non-union following conservative treatment we considered excision of the bony fragment and first tarsometatarsal arthrodesis. This leads to a favourable functional outcome.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

This report is one of two products for this project with the other being a design guide. This report describes test results and comparative analysis from 16 different portland cement concrete (PCC) pavement sites on local city and county roads in Iowa. At each site the surface conditions of the pavement (i.e., crack survey) and foundation layer strength, stiffness, and hydraulic conductivity properties were documented. The field test results were used to calculate in situ parameters used in pavement design per SUDAS and AASHTO (1993) design methodologies. Overall, the results of this study demonstrate how in situ and lab testing can be used to assess the support conditions and design values for pavement foundation layers and how the measurements compare to the assumed design values. The measurements show that in Iowa, a wide range of pavement conditions and foundation layer support values exist. The calculated design input values for the test sites (modulus of subgrade reaction, coefficient of drainage, and loss of support) were found to be different than typically assumed. This finding was true for the full range of materials tested. The findings of this study support the recommendation to incorporate field testing as part of the process to field verify pavement design values and to consider the foundation as a design element in the pavement system. Recommendations are provided in the form of a simple matrix for alternative foundation treatment options if the existing foundation materials do not meet the design intent. The PCI prediction model developed from multi-variate analysis in this study demonstrated a link between pavement foundation conditions and PCI. The model analysis shows that by measuring properties of the pavement foundation, the engineer will be able to predict long term performance with higher reliability than by considering age alone. This prediction can be used as motivation to then control the engineering properties of the pavement foundation for new or re-constructed PCC pavements to achieve some desired level of performance (i.e., PCI) with time.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Desenvolupament d'aplicacions web en Django per al Segon Concurs de fotografia matemàtica FotoMath 2011. Allotjades en servidor Apachez, gestionades amb mòdul wsgi i relacionades amb una base de dades postgresql.