Wind Loads on Dynamic Message Cabinets and Behavior of Supporting Trusses, TR-612, 2013

Large Dynamic Message Signs (DMSs) have been increasingly used on freeways, expressways and major arterials to better manage the traffic flow by providing accurate and timely information to drivers. Overhead truss structures are typically employed to support those DMSs allowing them to provide wider display to more lanes. In recent years, there is increasing evidence that the truss structures supporting these large and heavy signs are subjected to much more complex loadings than are typically accounted for in the codified design procedures. Consequently, some of these structures have required frequent inspections, retrofitting, and even premature replacement. Two manufacturing processes are primarily utilized on truss structures - welding and bolting. Recently, cracks at welding toes were reported for the structures employed in some states. Extremely large loads (e.g., due to high winds) could cause brittle fractures, and cyclic vibration (e.g., due to diurnal variation in temperature or due to oscillations in the wind force induced by vortex shedding behind the DMS) may lead to fatigue damage, as these are two major failures for the metallic material. Wind and strain resulting from temperature changes are the main loads that affect the structures during their lifetime. The American Association of State Highway and Transportation Officials (AASHTO) Specification defines the limit loads in dead load, wind load, ice load, and fatigue design for natural wind gust and truck-induced gust. The objectives of this study are to investigate wind and thermal effects in the bridge type overhead DMS truss structures and improve the current design specifications (e.g., for thermal design). In order to accomplish the objective, it is necessary to study structural behavior and detailed strain-stress of the truss structures caused by wind load on the DMS cabinet and thermal load on the truss supporting the DMS cabinet. The study is divided into two parts. The Computational Fluid Dynamics (CFD) component and part of the structural analysis component of the study were conducted at the University of Iowa while the field study and related structural analysis computations were conducted at the Iowa State University. The CFD simulations were used to determine the air-induced forces (wind loads) on the DMS cabinets and the finite element analysis was used to determine the response of the supporting trusses to these pressure forces. The field observation portion consisted of short-term monitoring of several DMS Cabinet/Trusses and long-term monitoring of one DMS Cabinet/Truss. The short-term monitoring was a single (or two) day event in which several message sign panel/trusses were tested. The long-term monitoring field study extended over several months. Analysis of the data focused on trying to identify important behaviors under both ambient and truck induced winds and the effect of daily temperature changes. Results of the CFD investigation, field experiments and structural analysis of the wind induced forces on the DMS cabinets and their effect on the supporting trusses showed that the passage of trucks cannot be responsible for the problems observed to develop at trusses supporting DMS cabinets. Rather the data pointed toward the important effect of the thermal load induced by cyclic (diurnal) variations of the temperature. Thermal influence is not discussed in the specification, either in limit load or fatigue design. Although the frequency of the thermal load is low, results showed that when temperature range is large the restress range would be significant to the structure, especially near welding areas where stress concentrations may occur. Moreover stress amplitude and range are the primary parameters for brittle fracture and fatigue life estimation. Long-term field monitoring of one of the overhead truss structures in Iowa was used as the research baseline to estimate the effects of diurnal temperature changes to fatigue damage. The evaluation of the collected data is an important approach for understanding the structural behavior and for the advancement of future code provisions. Finite element modeling was developed to estimate the strain and stress magnitudes, which were compared with the field monitoring data. Fatigue life of the truss structures was also estimated based on AASHTO specifications and the numerical modeling. The main conclusion of the study is that thermal induced fatigue damage of the truss structures supporting DMS cabinets is likely a significant contributing cause for the cracks observed to develop at such structures. Other probable causes for fatigue damage not investigated in this study are the cyclic oscillations of the total wind load associated with the vortex shedding behind the DMS cabinet at high wind conditions and fabrication tolerances and induced stresses due to fitting of tube to tube connections.

Density, climate and varying return points: an analysis of long-term population fluctuations in the threatened European tree frog.

Experimental research has identified many putative agents of amphibian decline, yet the population-level consequences of these agents remain unknown, owing to lack of information on compensatory density dependence in natural populations. Here, we investigate the relative importance of intrinsic (density-dependent) and extrinsic (climatic) factors impacting the dynamics of a tree frog (Hyla arborea) population over 22 years. A combination of log-linear density dependence and rainfall (with a 2-year time lag corresponding to development time) explain 75% of the variance in the rate of increase. Such fluctuations around a variable return point might be responsible for the seemingly erratic demography and disequilibrium dynamics of many amphibian populations.

Lignes ferroviaires régionales : ouvrir, fermer ou moderniser? : obstacles juridiques, techniques, géopolitiques ou absence de volonté politique? : études de quatre lignes ferroviaires franco-belges et franco-suisses

L'objectif de la présente étude est de cerner les facteurs de succès et d'échec des réouvertures et modernisations de lignes ferroviaires transfrontalières dans les zones limitrophes. L'enquête prend pour base deux lignes franco-belges (Mons-Valenciennes et Namur- Charleville-Mézières) et deux lignes franco-suisses (Delémont-Belfort et Neuchâtel- Besançon). Le problème public réside dans l'absence de moyens de transports publics exploitant le potentiel existant dans le bassin de vie concerné (sous-exploitation du marché des transports). Les obstacles à franchir dans le domaine des transports ferroviaires peuvent être de nature juridique. Ainsi, des prescriptions légales telles que certains standards d'interopérabilité, l'absence d'une définition de l'expression «train régional» au niveau européen, la sécurité (passages à niveau) ou des mesures en faveur des personnes à mobilité réduite, peuvent entraver, voire empêcher des réouvertures ou modernisations de lignes régionales, car ces standards ne sont pas adaptés à la réalité des lignes dont le potentiel est faible en termes de voyageurs et de fret. À un autre niveau, il est rare que les aspects techniques constituent des obstacles. C'est cependant le cas lorsque deux réseaux ferroviaires nourrissent des philosophies antagonistes (réseau cadencé et non cadencé). Pour la réouverture des lignes, on constate l'absence de définitions claires, au niveau politique, de la desserte de base et des seuils de fréquentation minimale. Il y a parfois un contraste marqué entre une infrastructure dégradée et un matériel roulant très moderne, signe d'absence de sensibilisation à l'entretien des infrastructures ferroviaires. Pourtant, ces infrastructures jouent un rôle important à l'échelon géopolitique. Correctement aménagées (offre, temps de parcours, correspondances), elles permettent le désenclavement de toute une région. La réouverture d'un chaînon manquant peut changer la position géopolitique d'une région, comme dans le cas de Mons-Valenciennes; mais en même temps, l'argument de l'impact géopolitique peut entraver une réouverture, même lorsqu'il n'est pas fondé, comme le montre le cas de Dinant-Givet qui semble concurrencer une autre ligne existante. L'impact des lignes à grande vitesse sur les régions limitrophes est souvent surestimé. En revanche, la praticabilité du concept des quatre capitaux (capital manufacturé, social, naturel et humain) est sous-estimée dans le domaine des transports publics. Les grilles d'analyse des quatre capitaux nous ont en effet permis de prouver l'applicabilité du concept aux lignes ferroviaires transfrontalières, en dépit du manque de me- surabilité de certains indicateurs. L'évaluation des lignes retenues à l'aide de notre grille d'analyse montre que les lignes régionales françaises accusent un lourd retard en termes de performance. Ce fait est confirmé dans les quatre capitaux. En appliquant notre méthode de planification à des lignes ferroviaires (transfrontalières), on observe que les lignes actuelles n'exploitent pas suffisamment leur potentiel. L'approche proposée se base sur le triangle «offre - infrastructure - matériel roulant» et s'articule autour des usagers. Avant toute planification, il faut développer une vision pour la région et la ligne concernée, dans laquelle la voie ferrée servira d'axe structurant. La vision se manifeste par un horaire qui traduit l'offre sou-haitée à long terme avec des temps de parcours idéaux, et des noeuds de correspondance avec d'autres moyens de transport. Alors, les lignes régionales peuvent contribuer à un changement de paradigme qui favorise un mode de vie axé davantage sur les services des transports publics que sur le transport individuel, également dans les régions limitrophes. - Het doel van deze Studie is het onderzocken von de redenen van het succès en van het falen van de heropening of modernisering van al of niet grensoverschrijdende spoorlijnen. Het on- derzoek is gebaseerd op twee Frans-Belgische lijnen (Bergen-Yalenciennes en Namen- Charleville-Mezières) en twee Frans-Zwitserse lijnen (Delémont-Belfort en Neuchâtel- Besançon). Het probleem is de afwezigheid van openbare transportmogelijkheden in de uitbating van de betrokken woongebieden (onderbenutting van de transportmarkt). De te overschrijden hindernissen op het gebied van spoorwegvervoer kunnen van juridische oorsprong zijn. Dat wil zeggen dat wettelijke vereisten zoals bepaalde standaarden voor inte- roperabiliteit, het ontbreken van een definitie van «regionale trein» op Europees niveau, de beveiliging (spoorwegovergangen) of maatregelen voor mensen met verminderde mobiliteit de heropening of modernisering van de regionale lijnen kunnen verhinderen, aangezien deze normen niet zijn aangepast aan de realiteit op aan de lijnen waarvan het potenti eel laag is, zowel voor reizigers als voor goederen. Op een ander niveau is het zeldzaam dat de technische as-pecten voor obstakels zorgen. Het is nochtans het geval wanneer twee spoorwegnetten zorgen voor tegenstrijdige ideeën (regelmatig of onregelmatig bezet net). Om de lijnen te he- ropenen, is er een gebrek aan duidelijke afspraken op politiek niveau, voor een minimale be- diening en een minimale opkomst. Soms is er een groot contrast tussen een verouderde infras- tructuur en een zeer modem rollend materieel, een teken van gebrek aan gezond verstand bij het onderhoud van de spoorweginfrastructuur. Deze infrastructuur speelt echter een belan- grijke roi in het geopolitieke niveau. Goed beheerd (aanbod, reistijd, verbindingen) zorgen ze voor een heropening van een hele regio. De heropening van een ontbrekende schakel kan de geopolitieke positie van een regio veranderen, zoals in het geval van Bergen-Valenciennes, maar terzelfder tijd kan het argument van de geopolitieke impact een heropening verhinderen, zelfs als het ongegrond is, zoals in het geval van Dinant-Givet dat blijkt te concurreren met een andere bestaande lijn. De impact van hogesnelheidslijnen op grensoverschrijdende regio's wordt vaak overschat. Daartegenover wordt de haalbaarheid van het concept van de vier kapi- taalvlakken (opbouwend, sociaal, natuurlijk en menselijk kapitaal) onderschat op het gebied van openbaar vervoer. De analyse van de vier kapitaalvlakken heeft ons toegelaten de toepas- baar-heid van het concept van de grensoverschrijdende spoorlijnen aan te tonen, ondanks het ge-brek aan meetbaarheid van bepaalde indicatoren. Evaluatie van de lijnen, geselecteerd met behulp van ons analysekader, heeft aangetoond dat Franse regionale lijnen achterblijven op het gebied van prestaties. Dit wordt bevestigd op de vier kapitaalvlakken. Door het toepassen van onze planningsmethode op spoorlijnen (in grenszones), zien we dat de huidige lijnen hun potentieel onvoldoende benutten. De voorgestelde aanpak is gebaseerd op de driehoek «aan- bieding - infrastructuur - rollend materieel» en rieht zieh op de gebruikers. Vooraleer een planning opgesteld kan worden, moeten we een visie ontwikkelen voor de betrokken lijn en de regio waarin de spoorweg zal dienen als structurele as. De visie baseert zieh op een diens- tregeling die uitgaat van een aanbod op lange termijn met ideale rijtijden en knooppunten met an-dere transportmiddelen. Zodoende kunnen regionale lijnen bijdragen aan een paradigma- vers-chuiving die een levensstijl promoot die meer gericht is op het openbaar vervoer dan op het individueel vervoer, ook in naburige regio's. - Das Ziel der Studie ist die Identifizierung von Erfolgs- und Misserfolgsfaktoren bei Wiedereröffnungen und Modernisierungen von (grenzüberschreitenden) Regionalverkehrslinien in Randregionen. Die Untersuchung stützt sich auf zwei belgisch-französische (Mons- Valenciennes und Namur-Charleville-Mézières) sowie zwei schweizerisch-französische Linien (Delémont-Belfort und Neuchâtel-Besançon). Das öffentliche Problem besteht im Fehlen eines öffentlichen Verkehrsmittels, welches das vorhandene Potential im Einzugsbereich der betrachteten Linien vollständig ausnützt (unvollständige Ausnützung des vorhandenen Transportmarktes). Die zu überwindenden Hindernisse auf dem Gebiet des Eisenbahnwesens können juristischer Natur sein. Es handelt sich dabei um gewisse juristische Vorschriften w. z. B. Interoperabili- tätsstandards, die Abwesenheit einer klaren Definition des Begriffes «Regionalverkehr» auf europäischer Ebene, Sicherheitsstandards (Bahnübergänge) oder Massnahmen zu Gunsten von Behinderten, die Wiedereröffnungen behindern können, weil diese Standards keine Rücksicht auf die Gegebenheiten von Regionallinien mit einem geringen Nachfragepotential nehmen. Technische Vorgaben stellen nur selten ein Hindernis bei Wiedereröffnungen dar. Dies kann dann der Fall sein, wenn zwei Eisenbahnnetze mit unterschiedlichen Betriebsphilosophien aufeinander treffen (Netz mit Taktverkehr und unvertaktete Netze). Bei Wiedereröffnung von Eisenbahnlinie ist festzustellen, dass auf politischer Ebene keine Definitionen in Bezug auf Basisangebot und der minimalen Nachfrage bestehen. Bisweilen ist ein starker Kontrast zwischen einem schlechten Infrastrukturzustand und einem darauf verkehrenden modernem Rollmaterial festzustellen. Gerade diese Infrastruktur spielt auf geopolitischer Ebene eine wichtige Rolle. Wird diese korrekt betrieben (attraktives Angebot, Fahrzeit, Umsteigeverbindungen), erlaubt sie einer ganzen Region eine Lösung aus der Isolation. Die Wiedereröffnung eines fehlenden Teilstücks kann die geopolitische Situation einer Region positiv verändern, wie das Beispiel der Linie Mons-Valenciennes zeigt. Gleichzeitig kann das Argument der geopolitischen Position eine Wiedereröffnung behindern, auch wenn die vorgebrachten Argumente nicht stichhaltig sind, wie das Beispiel der Linie Dinant-Givet beweist, die angeblich einen bestehenden Eisenbahgüterverkehrskorridor konkurrenzieren soll. Der Einfluss von Hochgeschwindigkeitsstrecken auf Randregionen wird oft überschätzt. Im Gegensatz dazu wird die Anwendbarkeit des Konzeptes der vier Kapitalien (konstruiertes, soziales, natürliches und Human-Kapital) bei der Anwendbarkeit im öffentlichen Verkehr unters-chätzt. Der verwendete Analyseraster der vier Kapitalien erlaubt die Anwendbarkeit dieses Ansatzes auf grenzüberschreitende Eisenbahnlinien, trotz des Fehlens von Daten für zahlreiche Indikatoren, zu untermauern. Die Evaluation der betrachteten Linien hat gezeigt, dass die französischen Schienenregionalverkehrslinien einen bedeutenden Rückstand in Bezug auf die Leistungsfähigkeit vorweisen. Dies wird durch die Anwendung des Analyseraster der vier Kapitalien bestätigt. Der Einsatz, der in dieser Arbeit entwickelten Planungsmethode auf die vier grenzüberschreitenden Regionalverkehrslinien hat gezeigt, dass die heutige Betriebsweise von Regionalverkehrslinien das vorhandene Potential nicht ausschöpft. Der vorgeschlagene Ansatz basiert auf dem Dreieck «Angebot - Infrastruktur - Rollmaterial» in dem die Benützerlnnen im Zentrum stehen. Jedoch steht die Entwicklung einer Vision für die betroffene Region und Linie vor dem Beginn jeder Planung im Zentrum, bei der die Eisenbahnlinie als strukturierende Achse benützt wird. Diese manifestiert sich in einer Fahrplanstruktur, die das langfristig gewünschte Angebot mit idealen Fahrzeiten und Umsteigeknoten mit anderen Verkehrsmitteln beinhaltet. In dieser Weise können die Regionalverkehrslinien einen Beitrag zu einem Paradigmawechsel beitragen, der auch in Randregionen einen Lebensstil fördert, der vermehrt auf den öffentlichen Verkehr als auf den motorisierten Individualverkehr setzt. - L'obiettivo di questo studio è quello di identificare i fattori di successo e di fallimento relativi alla riapertura e modernizzazione di linee ferroviarie transfrontaliere e non in aree limitrofe. L'indagine si basa su due linee franco-belghe (Mons-Valenciennes e Namur-Charleville- Mézières) e due linee franco-svizzere (Delémont-Belfort e Neuchâtel-Besançon). Il problema pubblico è la mancanza di mezzi di trasporto pubblico che sfruttino il potenziale esistente nel bacino d'utenza interessato (sottoutilizzazione del mercato dei trasporti). Gli ostacoli da superare nel settore del trasporto ferroviario possono essere di natura giuridica - vale a dire, requisiti legali come alcuni standard d'interoperabilità, l'assenza di una definizione del termine «treno regionale» a livello europeo, la sicurezza (passaggi a livello) o misure a favore di persone a mobilità ridotta, che possono ostacolare o impedire la riapertura o modernizzazione di linee regionali poiché queste norme non vengono adattate alla realtà delle linee il cui potenziale è basso in termini di viaggiatori e merci. A un altro livello è raro che aspetti tecnici costituiscano degli ostacoli. Tuttavia è il caso quando due reti ferroviarie perseguono filosofie antagoniste (rete cadenzata e non cadenzata). Per riaprire le linee si rileva una mancanza di definizioni chiare, a livello politico, del collegamento di base e delle soglie minime di frequentazione. A volte vi è un netto contrasto tra un'infrastruttura degradata e un modernissimo materiale rotabile, segno della mancanza di sensibilizzazione per la manutenzione delle infrastrutture ferroviarie. Eppure queste strutture svolgono un ruolo importante a livello geopolitico. Correttamente gestite (offerta, tempi di percorrenza, coincidenze), permettono l'apertura verso l'esterno di un'intera regione. La riapertura di un tassello mancante può cambiare la posizione geopolitica di una regione, come nel caso di Mons-Valenciennes. Allo stesso tempo, tuttavia, l'argomento dell'impatto geopolitico, anche se infondato, può ostacolare una riapertura - come nel caso di Dinant-Givet che sembra fare concorrenza a un'altra linea esistente. L'impatto delle linee ad alta velocità sulle regioni limitrofe è spesso sovrastimato. In compenso, l'attuabilità del concetto dei quattro capitali (capitale fabbricato, sociale, naturale e umano) è sottovalutata nel settore dei trasporti pubblici. Le griglie d'analisi dei quattro capitali ci hanno effettivamente permesso di dimostrare l'applicabilità del concetto alle linee ferroviarie transfrontaliere, nonostante la mancanza di misurabilità di alcuni indicatori. La valutazione delle linee selezionate in supporto alla nostra griglia d'analisi mostra che le linee regionali francesi accusano un pesante ritardo in termini di prestazioni. Questo dato di fatto è confermato nei quattro capitali. Applicando il nostro metodo di pianificazione alle linee ferroviarie (transfrontaliere), si osserva che le attuali linee non sfruttano a sufficienza il loro potenziale. L'approccio proposto è basato sul triangolo «offerta / infrastrutture / materiale rotabile» e si articola attorno agli utenti. Prima di qualsiasi pianificazione, è necessario sviluppare una visione per la regione e la linea coinvolta, in cui la ferrovia servirà come asse strutturale. La visione si manifesta attraverso un orario che rifletta l'offerta desiderata a lungo termine, con tempi di percorrenza ideali e nodi di coincidenza con altri mezzi di trasporto. In questo modo, le linee regionali possono contribuire a un cambiamento di paradigma che favorisca uno stile di vita più focalizzato sui servizi di trasporto pubblico che sul trasporto individuale - anche nelle regioni limitrofe.

Monitoring butterfly abundance: beyond Pollard walks.

Most butterfly monitoring protocols rely on counts along transects (Pollard walks) to generate species abundance indices and track population trends. It is still too often ignored that a population count results from two processes: the biological process (true abundance) and the statistical process (our ability to properly quantify abundance). Because individual detectability tends to vary in space (e.g., among sites) and time (e.g., among years), it remains unclear whether index counts truly reflect population sizes and trends. This study compares capture-mark-recapture (absolute abundance) and count-index (relative abundance) monitoring methods in three species (Maculinea nausithous and Iolana iolas: Lycaenidae; Minois dryas: Satyridae) in contrasted habitat types. We demonstrate that intraspecific variability in individual detectability under standard monitoring conditions is probably the rule rather than the exception, which questions the reliability of count-based indices to estimate and compare specific population abundance. Our results suggest that the accuracy of count-based methods depends heavily on the ecology and behavior of the target species, as well as on the type of habitat in which surveys take place. Monitoring programs designed to assess the abundance and trends in butterfly populations should incorporate a measure of detectability. We discuss the relative advantages and inconveniences of current monitoring methods and analytical approaches with respect to the characteristics of the species under scrutiny and resources availability.

Atividade celulolítica de fungos isolados de bagaço de cana-de-açúcar e madeira em decomposição

O objetivo deste trabalho foi identificar isolados de fungos a partir de bagaço de cana-de-açúcar e madeira em decomposição e avaliar a sua atividade celulolítica em bagaço de cana. Cinco isolados foram avaliados, tendo-se como referências os fungos Trichoderma reesei QM9414 e T. reesei RUT C30. A atividade celulolítica foi estimada pela capacidade hidrolítica do extrato enzimático dos fungos cultivados em bagaço de cana sobre os substratos papel de filtro (atividade celulolítica total) e carboximetilcelulose sódica (atividade da endoglucanase). Os isolados foram identificados pela análise molecular da região 26S rDNA. Os gêneros Paecilomyces, Aspergillus, Acremonium/Penicillium e Trichoderma foram identificados. Embora T. reesei QM9414 tenha apresentado a mais alta atividade celulolítica total, alguns isolados também apresentaram alta atividade de endoglucanase. A biodiversidade, em nichos como bagaço de cana-de-açúcar, pode fornecer linhagens de fungos celulolíticos com grande potencial biotecnológico.

Ontología de ALUS

En este trabajo se describe una base de conocimiento de las ALU humanas. La ontología incorpora términos SO y GO y está orientada a describir el contexto genómico del conjunto de ALU. Para cada elemento ALU se almacenan el gen y transcrito más cercanos, así como su anotación funcional de acuerdo a GO, el estado de la cromatina circundante y los factores de transcripción presentes en la ALU. Se han incorporado reglas semánticas para facilitar el almacenamiento, consulta e integración de la información. La ontología de ALU es plenamente analizable mediante razonadores como Pellet y está parcialmente transferida a una wiki semántica.

Composição mineral de maçãs 'Gala' e 'Fuji' produzidas no Sul do Brasil

O objetivo deste trabalho foi avaliar a composição mineral de maçãs 'Gala' e 'Fuji', em pomares de diferentes regiões do Sul do Brasil. Foram avaliados pomares em vários municípios de Santa Catarina e do Rio Grande do Sul, agrupados em macrorregiões denominadas de Fraiburgo, Vacaria e São Joaquim, durante o período de 1991 a 2007. Os teores médios (em matéria fresca) de Ca, K, Mg, N e P nos frutos foram, respectivamente, 47, 1.027, 52, 419 e 116 mg kg‑1, para 'Gala', e de 41, 1.043, 46, 373 e 116 mg kg‑1, para 'Fuji'. Os valores médios das relações (K+Mg)/Ca e N/Ca foram respectivamente de 24 e 9,6, para 'Gala', e de 28 e 9,7, para 'Fuji'. Maçãs 'Gala' e 'Fuji' apresentaram teores médios de Ca e P acima dos níveis críticos mínimos (40 e 100 mg kg‑1, respectivamente), e relações médias de (K+Mg)/Ca e N/Ca acima dos níveis críticos máximos (30 e 14), considerados adequados para maior conservação da qualidade pós‑colheita (QPC). Maçãs de pomares de São Joaquim apresentaram maiores teores de Ca e P, menores teores de N e menores relações (K+Mg)/Ca e N/Ca, independentemente da cultivar. O percentual de amostras, com alto risco de perdas em QPC, foi maior para 'Fuji' do que para 'Gala', quanto aos teores de Ca e P e às relações (K+Mg)/Ca e N/Ca.

Análise de componentes principais de atributos químicos e físicos do solo limitantes à produtividade de grãos

O objetivo deste trabalho foi avaliar, por meio da análise dos componentes principais, a redução na dimensionalidade de atributos químicos e físicos do solo para a compreensão da variabilidade espacial e temporal da produtividade de culturas de grãos. A área experimental, de 54 ha, é manejada em agricultura de precisão há oito anos. Com base em seis mapas de colheita (soja - safra 2000/2001; milho - 2001/2002; soja - 2002/2003; trigo - 2003; soja - 2003/2004; e milho - 2004/2005), a área foi dividida em três zonas de produtividade de grãos (alta, média e baixa). Foram definidos 15 pontos georreferenciados representativos, para determinação de atributos químicos e físicos do solo, o que totalizou 63 variáveis analisadas. Entre os atributos químicos, o elevado teor de K no solo é o que melhor explica a variabilidade espacial da produtividade das culturas de grãos, provavelmente em razão do desbalanço das relações Ca:K e Mg:K. A zona de baixa produtividade apresentou baixa qualidade física do solo. Neste caso, a infiltração de água no solo, isoladamente, é a variável que melhor explica o desempenho das culturas de grãos. A análise dos componentes principais dos atributos químicos e físicos do solo é estratégia eficiente para explicar a variabilidade espacial e temporal da produtividade de culturas de grãos.

Is It Possible to Predict the Manual Web Accessibility Result Using the Automatic Result?

The most adequate approach for benchmarking web accessibility is manual expert evaluation supplemented by automatic analysis tools. But manual evaluation has a high cost and is impractical to be applied on large websites. In reality, there is no choice but to rely on automated tools when reviewing large web sites for accessibility. The question is: to what extent the results from automatic evaluation of a web site and individual web pages can be used as an approximation for manual results? This paper presents the initial results of an investigation aimed at answering this question. He have performed both manual and automatic evaluations of the accessibility of web pages of two sites and we have compared the results. In our data set automatically retrieved results could most definitely be used as an approximation manual evaluation results.

Secure Dynamic MANET On-demand (SEDYMO) Routing Protocol

This paper describes the state of the art of secure ad hoc routing protocols and presents SEDYMO, a mechanism to secure a dynamic multihop ad hoc routing protocol. The proposed solution defeats internal and external attacks usinga trustworthiness model based on a distributed certification authority. Digital signatures and hash chains are used to ensure the correctness of the protocol. The protocol is compared with other alternatives in terms of security strength, energy efficiency and time delay. Both computational and transmission costs are considered and it is shown that the secure protocol overhead is not a critical factor compared to the high network interface cost.

Feed intake and growth performance of goats supplemented with soy waste

The objective of this work was to evaluate the effects of supplemental feeding of soy waste on the feed intake and growth rate of goats. Twenty male crossbred (Boer x local) goats were assigned to two isonitrogenous diet groups: one of commercial pellet and the other of soy waste. The commercial pellet (1.0%) and soy waste (0.8%) were provided on the dry matter basis of body weight (BW) per day, to the respective group of each diet. The soy waste group had lower daily intakes of total dry matter (0.79 vs. 0.88 kg) and organic matter (665.71 vs. 790.44 g) than the group fed pellet; however, the differences on daily intakes for grass (0.62 vs. 0.64 kg), crude protein (96.81 vs. 96.83 g), and neutral detergent fibre (483.70 vs. 499.86 g) were not significant. No differences were observed between groups for BW gain. The feed conversion ratio and feed cost per kilogram of BW gain were lower for the group fed soy waste than for the one fed pellet. Goats fed supplemental soy waste have a lower total dry matter intake, feed conversion ratio, and feed cost per kilogram of body weight gain than those fed commercial pellets.

Säätöventtiilin virtaustekniset ominaisuudet

Virtauslaskennan käyttö jokapäiväisessä insinöörityössä on lisääntynyt viime vuosina nopeaa vauhtia. Virtauslaskennan avulla voidaan tutkia säätöventtiilin virtauskenttää, mikä antaa suunnittelijalle mahdollisuuden korjata virtauskanavan ongelmakohtia jo tuotekehityksen alkuvaiheessa. Tämändiplomityön tavoitteena on määrittää uuden säätöventtiilin mitoituskertoimet jatutkia virtauslaskennan käytettävyyttä säätöventtiilisuunnittelussa. Teoreettisessa tarkastelussa on käsitelty venttiilivirtaukselle ominaisia virtausteknisiä yhtälöitä ja ilmiöitä, säätöventtiilin standardin määräämiä mitoitusyhtälöitä sekä neste- että kaasumelua. Lisäksi kerrotaan yleisimmistä säätöventtiilisovellutuksista ja esitellään suunnitteilla oleva uusi säätöventtiili. Virtauslaskennan avulla tutkittiin venttiilin kapasiteettiaja virtauskenttää. Alustavaa laskentaa tehtiin venttiilin paineenpalautumiskertoimen ja alkavan kavitaation määrittämiseksi. Virtauslaskenta tehtiin Fluent ja Cfdesign -virtauslaskentaohjelmilla. Virtauslaskennan antamia tuloksia verrattiin laboratoriossa saatuihin mittaustuloksiin. Laboratoriokokeiden avulla määritettiin uuden säätöventtiilin mitoituskertoimet. Lisäksi mitattiin säätöventtiilin aiheuttamaa neste- ja kaasumelua.

Fluid flow and dispersion predictions in porous media by utilizing advanced numerical methods

Diplomityön tavoitteena oli tarkastella numeerisen virtauslaskennan avulla virtaukseen liittyviä ilmiöitä ja kaasun dispersiota. Diplomityön sisältö on jaettu viiteen osaan; johdantoon, teoriaan, katsaukseen virtauksen mallinnukseen huokoisessa materiaalissa liittyviin tutkimusselvityksiin, numeeriseen mallinnukseen sekä tulosten esittämiseen ja johtopäätöksiin. Diplomityön alussa kiinnitettiin huomiota erilaisiin kokeellisiin, numeerisiin ja teoreettisiin mallinnusmenetelmiin, joilla voidaan mallintaa virtausta huokoisessa materiaalissa. Kirjallisuusosassa tehtiin katsaus aikaisemmin julkaistuihin puoliempiirisiin ja empiirisiin tutkimusselvityksiin, jotka liittyvät huokoisen materiaalin aiheuttamaan painehäviöön. Numeerisessa virtauslaskenta osassa rakennettiin ja esitettiin huokoista materiaalia kuvaavat numeeriset mallit käyttäen kaupallista FLUENT -ohjelmistoa. Työn lopussa arvioitiin teorian, numeerisen virtauslaskennan ja kokeellisten tutkimusselvitysten tuloksia. Kolmiulotteisen huokoisen materiaalinnumeerisessa mallinnuksesta saadut tulokset vaikuttivat lupaavilta. Näiden tulosten perusteella tehtiin suosituksia ajatellen tulevaa virtauksen mallinnusta huokoisessa materiaalissa. Osa tässä diplomityössä esitetyistä tuloksista tullaan esittämään 55. Kanadan Kemiantekniikan konferenssissa Torontossa 1619 Lokakuussa 2005. ASME :n kansainvälisessä tekniikan alan julkaisussa. Työ on hyväksytty esitettäväksi esitettäväksi laskennallisen virtausmekaniikan (CFD) aihealueessa 'Peruskäsitteet'. Lisäksi työn yksityiskohtaiset tulokset tullaan lähettämään myös CES:n julkaisuun.

Characterization of membrane vesicles circulating in the serum of patients with common acute lymphoblastic leukemia.

Common acute lymphoblastic leukemia antigen detected by radioimmunoassay in the serum of patients with common acute lymphoblastic leukemia was found to be exclusively associated with the pellet of the serum samples obtained by ultracentrifugation at 100,000 X g. The pellets were shown to contain membrane vesicles or fragments which were characterized by electron microscopy and determination of enzymatic activity. The pelleted fragments had an apparent diameter ranging between 60 and 260 nm and showed a trilaminar membrane structure. On freeze-fracture preparations, the fragments with concave profile, corresponding to the external fracture face of plasma membrane, displayed an intramembrane particle density (ranging from 0 to 750 particles per micron2) which is similar to that recorded on the corresponding fracture face of intact cells from the common lymphoblastic leukemia antigen positive leukemic cell line (Nalm-1) or of vesicles shed in the culture medium by Nalm-1 cells. Furthermore, analysis of the membrane enzyme marker 5'-nucleotidase in the pellet of patient's sera, showed that the presence of this enzyme correlated with that of common lymphoblastic leukemia antigen, but the quantitative relationship between the two surface constituents was not linear. The results suggest that the two markers are located on the same membrane fragments, but that their individual distribution on the shed fragments is heterogeneous.

Transonic flow past on enlarged missile nose parts

Numerical computation of a viscid heat-conducting transonic flow over a generic commercial rocket profile with symmetric oversized nose part was carried out. It has been shown that at zero angle of attack for some free-streamvelocity value flow pattern loses its symmetry. This results in non-uniform pressure distribution on rocket surface in angle direction which may yield in additional oscillating stress on the rocket. Also it has been found that obtained non-symmetric flow patterns are stable for small velocity perturbations.