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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

Skirtingu laiku sėtų rapsų žiemojimo priklausomumas nuo skrotelės morfometrinių rodiklių kintančio klimato sąlygomis / The Dependence of Over Wintering of Winter Rape Sown at Different Dates on the Morfometric Parameters of Rosette in Changeable Climatic Conditions

Kedytė, Vaida 03 June 2011 (has links)
Eksperimentai atlikti 2009–2010 m. Lietuvos žemės ūkio universiteto bandymų stotyje, kur dirvožemis karbonatingas sekliai glėjiškas išplautžemis (Calc(ar)i-Epihypogleyic Luvisol), o prieš sėją dirvožemio pH – 6,7, judriojo fosforo – 235 mg kg-1, judriojo kalio – 189 mg kg-1. Mūsų tyrimo tikslas buvo nustatyti sėjos laiko įtaką žieminių rapsų skrotelės formavimuisi rudenį ir peržiemojimui kintančio klimato sąlygomis. Atlikus tyrimus, nustatyta, kad pagal biometrinius parametrus, žieminiai rapsai, sėti rugpjūčio 20 d. – rugsėjo 5 d., buvo geriausiai pasiruošę žiemojimui: jie turėjo 6,4–9,6 lapus, šaknies kaklelio storis buvo 4,5–10,2 mm, viršūninio pumpuro aukštis buvo 9,1–45,6 mm. Žieminių rapsų hibridinės veislės 'Kronos', auginimas ir vystymasis rudenį bei peržiemojimas, buvo geresni, negu žieminių rapsų linijinės veislės 'Sunday'. Žieminai rapsai veislės 'Kronos' ir 'Sunday', sėti rugpjūčio 30 d. – rugsėjo 5 d. peržiemojo geriausiai. Hibridiniai rapsai buvo mažiau jautrūs sėjos laikui, nes jie tiek ankstyvesnės (rugpjūčio 10-20 d.), tiek vėlyvesnės (rugsėjo 10 d.) sėjos peržiemojo geriau už linijinius. Labai vėlyva rapsų sėja turėjo neigiamą įtaką žiemojimui. Pasėti rugsėjo 15 d. tiek ‘Sunday’, tiek ‘Kronos’ veislių žieminių rapsų pasėliai neperžiemojo. Rapsų žiemojimas priklausė nuo skrotelės lapų skaičiaus, šaknies kaklelio storio ir viršūninio pumpuro aukščio bei nuo temperatūrų, didesnių nei +2oC sumos, kuri stipriais koreliaciniais ryšiais tiesiogiai susieta su rapsų... [toliau žr. visą tekstą] / The experiment carried out in 2009–2010 in the Experimental Station of Lithuanian University of Agriculture, where is shallow calcareous luvisol (Calc(ar)i-Epihypogleyic Luvisol) and before sowing soil pH – 6.7, phosphorus 235 mg kg-1, potassium – 189 mg kg-1. Aim of our research was to determine the effect of sowing time of winter oilseed rape in autumn and during the winter changing climatic conditions. The research showed that according to biometric parameters, winter rape, sown on 20 August – 5 September, was best prepared for the winter: they had 6.4 - 9.6 leaves, root of the neck thickness was 4.5–10.2 mm, apical bud height was 9.1–45.6 mm. The growth and development in the autumn and during the winter, of hybrid winter rape variety 'Kronos', was better than the linear variety of winter rape 'Sunday'. Winter rape varieties 'Kronos' or 'Sunday', sown on 30 August – 5 September, over wintered best. Hybrid rape were less sensitive to sowing date, because they both of earlier (10–20 August) and late (10 September) sowing dates over wintered better than linear. Very late sowing date had a negative impact on the over wintering. Sown on 15 September 'Sunday' and 'Kronos' varieties of winter rape crop has not over wintered. Rape wintering depends on the number of rosette leaves, root collar thick ness, apical bud height and the sum of high temperatures, higher than +2oC the which is in the strong possitive correlation wish the rape crowns morphometric parameters.
232

Hodnocení úrovně psychického a fyzického zatížení závodníků ve Winter Survivalu včetně syntézy knowhow k organizaci podobných typů závodů. / Evaluation of a psychical and physical loading of competitors in the winter survival race with a knowhow manual for organisating similar types of competitions.

Migdau, Jan January 2011 (has links)
Title of thesis: Evaluation of psychologically and physically load in competitors of Winter Survival; including incorporation of knowhow to hold the competition. Aim of thesis: 1. Creation of a manual to order competition of Winter Survival type in civil and army. 2. Valorize and confront physically load in Winter Survival 2007, 2008, 2011. 3. Valorize and confront psychologically load in Winter Survival 2007, 2008, 2011. Methods: 1. For the creation of the manual was used qualitative research with exploitation of interview with abstract questions. 2. To valorizing and fixing of physically load was used quantitative study. 3. To valorizing and fixing of psychologically load was used quantitative study. Results: 1. We created the "manual" to ordering and organising of cometition for trainee officials of competitions like Winter Survival. 2. The results prove, that competitors of WS moved around middle zone of physical load. WS 2008 was, in light of physical load, much easier, than WS 2007 and 2011. Effect of the extension in 2. part of competition is the extension of physical work in middle zone of physical load to the prejudice moderate zone. 3. Mental condition is impressed with physical load in "state" and "activity" parameter, less connections are between physical load and "mood" parameter; the...
233

Wintertraum Sächsische Schweiz

01 March 2022 (has links)
Weitblick, Waldluft, Wanderwege: Die Nationalparkregion Sächsische Schweiz ist ein fantastisches Reiseziel. Das heißt, eigentlich sind es zwei: Die Sächsische Schweiz im Sommer und die Sächsische Schweiz im Winter. Im Sommer ist sie eine der beliebtesten deutschen Urlaubsregionen für Aktive. Millionen Wanderer, Kletterer, Radler, Camper und Paddler erleben hier das große Elbsandsteinabenteuer. Im Winter ist die Sächsische Schweiz ein Geheimtipp, ein Refugium für Romantiker, Genießer und Stadtflüchter. Nur Kenner kommen jetzt hierher. Die Felsenwelt zeigt sich von ihrer wilden und unergründlichen Seite. Fällt Schnee, entstehen märchenhafte Szenen, die ein Leben lang im Gedächtnis bleiben. Wie Kleckerburgen mit Zuckerguss stehen die Formationen dann in der Landschaft. Winterwandern ist eine herrliche Möglichkeit, die schlafende Naturschönheit zu bewundern. Wanderwege und Aussichtspunkte hat man meist für sich allein. Und die schönsten Orte und Hotels schnüren spannende Erlebnis- und Wohlfühlpakete. Winter in der Sächsischen Schweiz: ein Traum!
234

Wintertraum Sächsische Schweiz

01 March 2022 (has links)
Weitblick, Waldluft, Wanderwege: Die Nationalparkregion Sächsische Schweiz ist ein fantastisches Reiseziel. Das heißt, eigentlich sind es zwei: Die Sächsische Schweiz im Sommer und die Sächsische Schweiz im Winter. Im Sommer ist sie eine der beliebtesten deutschen Urlaubsregionen für Aktive. Millionen Wanderer, Kletterer, Radler, Camper und Paddler erleben hier das große Elbsandsteinabenteuer. Im Winter ist die Sächsische Schweiz ein Geheimtipp, ein Refugium für Romantiker, Genießer und Stadtflüchter. Nur Kenner kommen jetzt hierher. Die Felsenwelt zeigt sich von ihrer wilden und unergründlichen Seite. Fällt Schnee, entstehen märchenhafte Szenen, die ein Leben lang im Gedächtnis bleiben. Wie Kleckerburgen mit Zuckerguss stehen die Formationen dann in der Landschaft. Winterwandern ist eine herrliche Möglichkeit, die schlafende Naturschönheit zu bewundern. Wanderwege und Aussichtspunkte hat man meist für sich allein. Und die schönsten Orte und Hotels schnüren spannende Erlebnis- und Wohlfühlpakete. Winter in der Sächsischen Schweiz: ein Traum!
235

Felsenwinter: Auszeit mit Weitblick

Hesse, Nicole, Brückner, Yvonne 01 March 2022 (has links)
Eine Felsenwelt wie im Märchen. Wilde Schluchten und Abgründe, skurrile Felsentürme und gewaltige Tafelberge mit endlosem Weitblick. Klingt magisch, oder? Und im Winter gibt es für Dich noch ein Sahnehäubchen hinzu. Nicht nur auf den Felsen! Denn in der kalten Jahreszeit ist die Sächsische Schweiz tatsächlich noch ein Geheimtipp, ein Refugium für Romantiker, Genießer und Stadtflüchter. Die Felsenwelt zeigt sich von ihrer wilden und unergründlichen Seite. Fällt Schnee, entstehen märchenhafte Szenen, die ein Leben lang im Gedächtnis bleiben. Wie Kleckerburgen mit Zuckerguss stehen die Formationen dann in der Landschaft. Winterwandern ist eine herrliche Möglichkeit, die schlafende Naturschönheit zu bewundern.
236

Analysis of Using V2X DSRC Equipped Snowplows to Request Signal Preemption

Lau, Samantha Kathleen 04 August 2022 (has links)
Dedicated short-range communication (DSRC) systems, a form of vehicle-to-everything (V2X) systems, were placed on Utah Department of Transportation (UDOT) snowplows to request signal preemption. The study took place along five state routes in the Salt Lake City metropolitan area. Snowplows and intersections were equipped with the technology to communicate and process requests for signal preemption. Signal performance and vehicle performance analysis were performed to understand the impacts that snowplows requesting signal preemption had. Signal performance analysis was done to determine how snowplows with V2X systems using DSRC affected signals. Vehicle performance analysis was done to see if plowing and traffic efficiency and performance were improved, as well as evaluating safety implications of signal preemption. To perform the signal performance analysis, V2X data were collected to understand how often signal preemption was requested by snowplows, how often it was granted by signal controllers, and how long preemption requests affected signal controller timing. Snowplows requested preemption over 50 percent of the time they approached a signalized intersection. Of messages that requested signal preemption, over 80 percent were granted. On average, signal controllers are affected by preemption processing for less than 5 minutes. This shows that the system works as designed, is used often, and does not have adverse effects on signal controller. Data for vehicle performance analysis included analysis of snowplow speed data, general travel speed data, and crash data. These were collected to analyze the effects of snowplows requesting signal preemption on vehicle performance. The analysis showed that snowplow speeds are not changed due to the signal preemption system, but the number of times snowplows stopped was reduced. General travel speeds on equipped routes were more consistently closer to the speed limits than not equipped routes. Crash data showed a greater negative decrease on equipped routes than on not equipped routes. These findings showed minimal changes or impacts to vehicle performance, but anecdotal evidence from snowplow drivers indicates benefits from the system overall. There were various limitations in the analysis. Data granularity differed among datasets, making comparison between the different datasets difficult without reducing data integrity. Some datasets did not have much data, making statistical significance unclear. With these data limitations, conclusions were drawn, but do not fully describe all the potential benefits and impacts of snowplows with V2X systems that use DSRC to request signal preemption. Additional research is needed to better understand the impacts that snowplows requesting signal preemption has on different maintenance metrics, such as fuel usage and time spent plowing. It is also recommended that data used is explored for ways to improve the granularity.
237

A place called school

Conrad, Carolyn Nancy January 1990 (has links)
The thesis is an exploration of architectural ideas. An exploration which is still ongoing. It is learning how the ideas are realized in terms of materiality and structure. It is how the ideas become the structural, visual language of the building. The thesis is also the study of the institution of school. It is how the school, through its architecture, becomes a place. A place to provide inspiration. / Master of Architecture
238

Vernalization requirements and seed dormancy of jointed goatgrass (Aegilops cylindrica)

Fandrich, Lynn 12 October 2005 (has links)
Jointed goatgrass (Aegilops cylindrica Host) infestations in winter wheat (Triticum aestivum L.) production regions of the central and western USA result in severe economic losses in the wheat market. Field and greenhouse studies were conducted to determine the vernalization requirements of winter wheat, spring wheat, jointed goatgrass, and wheat by jointed goatgrass reciprocal hybrid plants. In field studies, jointed goatgrass plants required more vernalization to produce spikelets and germinable seed than 'Madsen' winter wheat plants. In greenhouse studies, plants of jointed goatgrass populations collected from Oregon and Washington wheat fields required fewer vernalization days to reach the joint stage than Madsen plants. Detailed observations in the greenhouse revealed a longer period between jointing and anthesis for most jointed goatgrass populations that was overlooked in field studies. Vernalization for 6-wk represents the minimum treatment for synchronous reproductive development among jointed goatgrass populations, Madsen winter wheat, and Madsen by jointed goatgrass hybrids, yet the risk of gene transfer might be greater after 7-wk vernalization. In the jointed goatgrass populations tested, there was not selection for a vernalization insensitive growth habit. Because jointed goatgrass spikelets often contain two seed, germination was recorded for primary and secondary positioned seed. Germination of freshly harvested jointed goatgrass seed was promoted by 25/15 C day/night temperatures. However, light and 30/20 C incubation was necessary for maximum germination of non-dormant, primary positioned seed. Both primary and secondary positioned seed within jointed goatgrass spikelets were non-dormant after 16-wk after-ripening at 22 ± 2 C. Under optimum growing conditions, no planting depth selectively allowed wheat germination and emergence while preventing jointed goatgrass germination and emergence. Glume removal did not alleviate dormancy completely in jointed goatgrass seed. Research confirmed jointed goatgrass population polymorphism for vernalization requirements and seed dormancy. Jointed goatgrass reproductive variability might be part of a general purpose genotype strategy to germinate and colonize a wide range of environments. Wheat by jointed goatgrass hybrid plants should be removed from winter and spring wheat fields. Despite a short dormancy period, three or more years of rotation outside of winter annual crops may be necessary to reduce populations of jointed goatgrass. / Graduation date: 2006
239

Architecture de la pousse de pommier en réponse à des températures hivernales froides et douces : typologie de la ramification axillaire au printemps et relation avec le statut hydrique du bourgeon pendant l'hiver précédent / Arquitetura da macieira em regimes térmicos hibernais contrastantes : tipologia da ramificação primaveril e sua relaç ão com o estado hídrico de gemas durante o inverno

Schmitz, Juliano 03 December 2014 (has links)
Le pommier (Malus Xdomestica Borkh.) cultivé en climat à hiver doux, avec un manque d'une quantité suffisante d'heures de températures froides, présente des anomalies morphologiques et physiologiques. Sur le plan de la phénologie, il s'agit notamment d'un débourrement printanier tardif et désynchronisé entre les différents bourgeons d'un même arbre. Sur le plan agronomique, la floraison et la nouaison sont irrégulières et étalées dans le temps et conduisent à une faible production de fruits. L'objectif de ce travail de thèse est premièrement de mieux caractériser les effets des températures hivernales sur le débourrement et la croissance des bourgeons axillaires en distinguant les effets respectifs des températures hivernales et du génotype. Il s'agit ensuite de vérifier l'hypothèse que les effets des températures sur le débourrement du bourgeon s'effectue via les effets sur son statut hydrique. Les travaux ont été réalisés en France et au Brésil. En France, les expérimentations ont porté sur quatre cultivars à fort besoin (‘Granny Smith', ‘Royal Gala', ‘Starkrimson') ou faible besoin (‘Condessa') en froid, cultivés en hiver froid (conditions extérieures) et doux (serres climatisées). Nous montrons que le débourrement résulte d'une séquence d'évènements où la température hivernale joue un rôle primordial sur les mécanismes de sortie de dormance et donc sur le débourrement proprement dit, durant la période froide. Les caractéristiques propres du cultivar jouent par contre un rôle dans la croissance ultérieure des bourgeons et donc dans l'architecture finale de la pousse du pommier. Par ailleurs, la chute tardive des feuilles, caractéristique du pommier en hiver doux, a peu d'effets sur le débourrement et la croissance des bourgeons. L'analyse du statut hydrique des bourgeons a été réalisée sur le tiers distal des pousses de pommier caractérisé par une forte fréquence de ramification en climat à hiver froid. Nous montrons que, dans la période allant de l'endordormance à la phase de pré-débourrement, la conductance hydraulique à la jonction entre l'axe porteur et le bourgeon varie peu au cours de l'hiver et entre cultivars. Par ailleurs, durant cette même période le potentiel hydrique intra-bourgeon reste négatif, entre -4.35 and -2.24 MPa. Enfin, quel que soit le cultivar, nous ne montrons pas de relation entre les températures hivernales, le potentiel hydrique ou la teneur relative en eau des bourgeons, et l'aptitude au débourrement ultérieur. Ces résultats suggèrent que le bourgeon est hydrauliquement isolé de son axe porteur pendant toute la période hivernale jusqu'à quelques jours précédant le débourrement. Les expérimentations au Brésil ont porté sur le cultivar ‘Eva ‘ à faible besoin en froid, cultivés en conditions naturelles d'hiver doux. Il s'agissait de vérifier les effets possibles de la position du bourgeon le long de l'axe porteur sur sa taille et sa teneur relative en eau. Nous montrons que, tout au long de l'hiver, les bourgeons distaux sont caractérisés par une plus grande taille et une teneur relative en eau plus élevée que les bourgeons proximaux avec une forte augmentation de la teneur relative en eau une semaine avant le débourrement printanier. Le débourrement acrotone semble donc résulter d'une évolution rapide du statut hydrique du bourgeon en fin d'écodormance. L'ensemble des résultats acquis en France et au Brésil, sur des cultivars caractérisés par des besoins variables en froid hivernal, indique que l'aptitude au débourrement printanier des bourgeons de pommier est davantage lié à un « effet rameau entier » qu'au statut hydrique proprement dit des bourgeons individuels, tout au moins jusqu'à quelques jours avant le débourrement effectif. La pousse annuelle de pommier apparait donc comme une unité morphologique et physiologique intégrée qui, dans un contexte climatique donné, conditionne le statut hydrique de chaque bourgeon et son aptitude au débourrement. / The apple tree (Malus Xdomestica Borkh.) presents morphological and physiological anomalies when grown in mild winter climates with insufficient winter chilling to overcome winter dormancy. Symptoms are typically delayed and erratic budburst, entailing desynchronized flowering and fruit-set and poor agronomic performances. This thesis aimed at gaining more insights on the following issues. Firstly, what are the effects of winter temperatures on axillary burdburst and bud outgrowth, and what are the respective effects of winter temperatures and cultivar?, and secondly, is there a link between the temperature-dependent budburst and bud water status? Works were done in France and Brazil. In France, experiments were carried out in controlled conditions on four apple cultivars characterized by either high chilling (‘Granny Smith', ‘Royal Gala', ‘Starkrimson') or low chilling (‘Condessa') requirements and were submitted to outdoor-cold and greenhouse-mild winter temperatures. We showed that the actual shoot architecture and budburst resulted from an ordered sequence of events with a pivotal role of winter temperatures on the dormancy completion of individual lateral buds. Endogenous factors related to the cultivar branching pattern overtook the temperature effect on the lateral bud outgrowth. Furthermore, the delayed senescence and subsequent leaf persistence during winter, characterizing the apple tree in the mild winter temperature conditions, had only a weak effect on the topological distribution of budburst and lateral outgrowth. The analyses of bud water status were done on distal buds only, characterized by high budburst frequency in cold winter conditions. We showed that, from endodormancy to the pre-budburst stage, xylem conductance at the stem-to-bud junction did not show consistent changes across cultivars and winter temperature treatments. Bud water potential had negative values, between -4.35 and -2.24 MPa, depending on cultivars and winter temperature treatments. Moreover, whatever the cultivar, there were no significant trends across dates for the effects of winter temperatures on bud water potential and relative water content without a consistent relationship with actual spring budburst frequency. These results suggested that lateral buds were hydraulically isolated from the parent stem during winter until a few days before budburst. The other set of experiments was carried out in Brazil, under mild winter conditions, on the low chilling apple cultivar ‘Eva'. The objectives were to gain more insights on the effect of the position of the over-wintering lateral bud along the whole-parent shoot on bud size and water content. Results highlighted that distal buds were larger and had a higher water content than proximal buds with a strong increase of water content a week before spring budburst. It was concluded that the acrotonic pattern of budburst was mainly established during ecodormancy. As a whole, we showed that spring budburst seemed more related to a whole-shoot effect than to the water status of the individual bud during winter dormancy. Our study substantiated the importance of the whole shoot as an integrated morphological and physiological unit in driving budburst and further growth.
240

Evaluierung von Winterackerbohnen als Zwischenfrucht für eine ökologische Biogasproduktion / Evaluation of winter faba bean as a first crop in a double-cropping system for an ecological biogas production

Roth, Franziska 15 July 2010 (has links)
No description available.

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