978 resultados para Position of the fruit in the canopy


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This investigation is in two parts, theory and experimental verification. (1) Theoretical Study In this study it is, for obvious reasons, necessary to analyse the concept of formability first. For the purpose of the present investigation it is sufficient to define the four aspects of formability as follows: (a) the formability of the material at a critical section, (b) the formability of the material in general, (c) process efficiency, (d) proportional increase in surface area. A method of quantitative assessment is proposed for each of the four aspects of formability. The theoretical study also includes the distinction between coaxial and non-coaxial strains which occur, respectively, in axisymmetrical and unsymmetrical forming processes and the inadequacy of the circular grid system for the assessment of formability is explained in the light of this distinction. (2) Experimental Study As one of the bases of the experimental work, the determination of the end point of a forming process, which sets the limit to the formability of the work material, is discussed. The effects of three process parameters on draw-in are shown graphically. Then the delay of fracture in sheet metal forming resulting from draw-in is analysed in kinematical terms, namely, through the radial displacements, the radial and the circumferential strains, and the projected thickness of the workpiece. Through the equilibrium equation of the membrane stresses, the effect on the shape of the unsupported region of the workpiece, and hence the position of the critical section is explained. Then, the effect of draw-in on the four aspects of formability is discussed throughout this investigation. The triangular coordinate system is used to present and analyse the triaxial strains involved. This coordinate system has the advantage of showing all the three principal strains in a material simultaneously, as well as representing clearly the many types of strains involved in sheet metal work.

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This research examines the relationship between 'race' and class in Britain. This is achieved by considering how these two concepts articulate in the overall structuring of class relationships in a society which is typified by the incorporatation of black labour into a majority white society, This relationship is examined through an investigation of those black workers who occupy a position in the objectively defined middle class. The basic theme underlying this research is that 'race, in the form of structural racism, plays a significant role at two levels. Firstly, it serves to structure the class position of black labour in Britain. Secondly, it serves to determine the type of race, class and political consciousness generated by black labour. The study was carried out in the London area. Occupation was used as an indicator of 'objective' class position when selecting respondents to be included in the two survey populations required for the research. A 'network' approach was used to actually locate the respondents. In-depth interviews were carried out with all the respondents. The study concludes that the concepts of 'race' and class are not independent of each other in the overall structuring of class relationships between black and white labour. It is argued that the inter-relationship identified between these two concepts serves to highlight the fact that the structural position of black labour, the type of consciousness generated and the type of decisions taken by those who took part in the research are to a large extent a result of the structural constraints deriving from the effects of structural racism in Britain.

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The topographical distribution of the pattern reversal Visual Evoked Response (VER) was recorded from a localised montage of 20 electrodes over the visual cortex. The response was recorded after stimulation with a black and white checkerboard stimulus. The effect of field location on the major components was investigated in 11 subjects (age range (23-55). The major components of the half field response were; a negative around 75ms (N75) followed by a positivity around 80ms (P80), then a positivity around 100ms (P100) followed by another positivity at around 120ms (P120) and a negativity at approximately 145ms (N145). No effect of field size could be demonstrated on either the amplitude or latency of the late negativity, N145. No significant effect of field size or location was shown on the latency of the P100 response. A delay previously shown in the upper half field response was therefore not substantiated. In contrast the amplitude of the major positivity, P100 was significantly affected by the field size and location. The amplitude of both P100 and N145 were significantly reduced following upper field stimulation when compared with the lower field response. No significant amplitude difference between the upper and lower field responses was demonstrated using electroretinography, the amplitude may therefore be reduced as a result of the ventral position of the upper field representation on the visual cortex. The lateral half field VEP was compared with the distribution of the visual evoked magnetic response (VEMR). The distribution of the VEMR supported the proposal that the paradoxical lateralisation of the VEP half field response is the result of the source being directed ipsilaterally. The morphology of the VEP following octant and double octant stimulation suggests that the response is generated in the striate cortex, with a reversal in response distribution following stimulation of the upper vertical and horizontal meridia.

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The thesis presents a theoretical and practical study of the dynamic behaviour of electromagnetic relays. After discussing the problem of solving the dynamicc equations analytically and presenting a historical survey of the earlier works in the relay and its dynamics, the simulation of a relay on the analogue computer is discussed. It is shown that the simulation may be used to obtain specific solutions to the dynamic equations. The computer analysis provides the dynamic characteristics for design purposes and may be used in the study of bouncing, rebound oscillations and stability of the armature motion. An approximate analytical solution to the two dynamic equations is given based on the assumption that the dynamic variation of the pull with the position of the armature is linear. The assumption is supported by the Computer-aided analysis and experimental results. The solution is intended to provide a basis for a rational design. A rigorous method of analysing the dynamic performance by using Ahlberg's theory is also presented. This method may be justified to be the extension of Ahlberg's theory by taking the mass and frictional damping forces into account. While calculating the armature motion mathematically, Ahlberg considers the equilibrium of two kinds of forces, namely pull and load, and disregards the mass and friction forces, whereas the present method deals with the equilibrium of all four kinds of forces. It is shown how this can be utilised to calculate the dynamic characteristics for a specific design. The utility of this method also extends to the study of stability, contact bounce and armature rebound. The magnetic circuit and other related topics which are essential to the study of relay dynamics are discussed and some necessary experimental results are given.

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The microstructural stability of aluminide diffusion coatings, prepared by means of a two-stage pack-aluminization treatment on single-crystal nickel-base superalloy substrates, is considered in this article. Edge-on specimens of coated superalloy are studied using transmission electron microscopy (TEM). The effects of coating thickness and post-coating heat treatment (duration, temperature, and atmosphere) on coating microstructure are examined. The article discusses the partial transformation of the matrix of the coating, from a B2-type phase (nominally NiAl) to a L12 phase (nominally Ni3(Al, Ti)), during exposure at temperatures of 850 °C and 950 °C in air and in vacuum for up to 138 hours. Three possible processes that can account for decom- position of the coating matrix are investigated, namely, interdiffusion between the coating and the substrate, oxidation of the coating surface, and aging of the coating. Of these processes, aging of the coating is shown to be the predominant factor in the coating transformation under the conditions considered. © 1992 The Minerals, Metals and Materials Society, and ASM International.

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This paper investigates whether the position of adverb phrases in sentences is regionally patterned in written Standard American English, based on an analysis of a 25 million word corpus of letters to the editor representing the language of 200 cities from across the United States. Seven measures of adverb position were tested for regional patterns using the global spatial autocorrelation statistic Moran’s I and the local spatial autocorrelation statistic Getis-Ord Gi*. Three of these seven measures were indentified as exhibiting significant levels of spatial autocorrelation, contrasting the language of the Northeast with language of the Southeast and the South Central states. These results demonstrate that continuous regional grammatical variation exists in American English and that regional linguistic variation exists in written Standard English.

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The aim of this paper is to analyze the political, social and economic background of the divergence of Belarusian and Ukrainian transitions. We focus on Belarus in order to find explanation for questions such as why could Lukashenko remain the authoritarian leader of Belarus, while in Ukraine the position of the political elite had proved less stable and collapsed in 2004. On the theoretical framework of elite-sociology, we seek to determine whether the internal factors (as macroeconomic conditions, standard of living, the oppressive nature of the political system and the structure of the political elite) play a significant role in the operation of the domino effect. This article emphasises the determining role of immanent internal factors, thus the political stability in Belarus can be explained by the role of the suppressing political regime, the hindrance of democratic rights and the relatively good living conditions that followed the transformational recession. Whilst in Ukraine, the markedly different circumstances brought forth the success of the Orange Revolution.

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The economic crisis has brought a new situation also for the Hungarian economic policy, as neoliberalism as the main trend in economic thought is no longer valid. This phenomenon cannot be reduced to be a mere macroeconomic course shift, as an entire economic philosophy and approach has lost its relevance. One consequence of this is the need for a thorough revision of the theory and practice of business management, along with the re-evaluation of the notion and position of the corporation. Our study aims to contribute to this theoretical reformation, presenting that social values derived from psychological and sociological findings such as human motivational theories or trust are fundamental elements of the 21st century corporate model. To point to this, we use the ideological correspondences, while proving that our national research on corporate theory and even rather its application are far behind the 21st century requirements and lack even the Western view of the 20th century.

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Ez a tanulmány a projektvezetési szakirodalomban kialakult ismeretanyagot szem előtt tartva (noha tételesen nem hivatkozva arra) tárja fel azt a sajátos és tipikusnak nevezhető kontextust, amelyben a projektalapú szervezetek projektmarketing tevékenysége megnyilvánul. A tanulmány célja tehát nem magának a projektmarketingnek a kérdéskörére irányul, hanem elsősorban annak projektspecifikus kontextusára. Jellegét illetően a tanulmány spekulatív jellegű, vagyis lényegét tekintve nem empirikus kutatási eredményekből levont következtetésekre épül. _____ Traditional approach to project marketing focuses on process-related aspects of the marketing efforts of project- based organisations. This paper is different. Unlike to the traditional approach it highlights the decisive contextual features of project marketing, bearing in mind the typical project business from the point of view of project-based organisations. These features include: a) instead of physically existing products project-based organisations need to sell their ability to create the project outcome physically; b) the project outcome and the conditions of implementation are defined by the project client; c) project clients are involved in creating the project outcome; d) project implementation strategy applied in a client organisation may vary project by project. These determining contextual features shape to a great extent the actual competitive position of the project-based organisations which may vary project by project even in relation to the very same project client.

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A tanulmány azt vizsgálja, milyen befolyással van a szervezetek kockázati attitűdje az általuk kötött szerződésre, elsősorban a projektszintű kockázatok megosztására. Esettanulmányként egy PPP-projekt szerződését használja fel, amely jól szemlélteti, hogy az eltérő kockázati magatartású szervezetek egymás közötti kockázatallokációja eltér az optimálistól. A konkrét esetben a közösségi aktor kerül kockázati aspektusból hátrányos helyzetbe. A vizsgálat eredménye, hogy meghatároz néhány kulcsparamétert, melyek a felek kockázati szempontból nyertes vagy vesztes pozícióját döntő módon befolyásolják. ___________ This paper examines the influence of the risk attitude of organizations on the contracts made by them, especially on allocation of the project level risk. A PPP project contract is used as a case study, because it illustrates expressively that the risk allocation between the concerned organiza tions with different risk attitudes differs from the optimal version. In this very case the public actor's position becomes disadvantageous. Specification some of the key parameters able to determine the winner or loser position of the risk taken parties is defined as the outcome of this study.

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The use of planktonic foraminifera in paleoceanographic studies relies on the assumption that morphospecies represent biological species with ecological preferences that are stable through time and space. However, genetic surveys unveiled a considerable level of diversity in most morphospecies of planktonic foraminifera. This diversity is significant for paleoceanographic applications because cryptic species were shown to display distinct ecological preferences that could potentially help refine paleoceanographic proxies. Subtle morphological differences between cryptic species of planktonic foraminifera have been reported, but so far their applicability within paleoceanographic studies remains largely unexplored. Here we show how information on genetic diversity can be transferred to paleoceanography using Globorotalia inflata as a case study. The two cryptic species of G. inflata are separated by the Brazil-Malvinas Confluence (BMC), a major oceanographic feature in the South Atlantic. Based on this observation, we developed a morphological model of cryptic species detection in core top material. The application of the cryptic species detection model to Holocene samples implies latitudinal oscillations in the position of the confluence that are largely consistent with reconstructions obtained from stable isotope data. We show that the occurrence of cryptic species in G. inflata, can be detected in the fossil record and used to trace the migration of the BMC. Since a similar degree of morphological separation as in G. inflata has been reported from other species of planktonic foraminifera, the approach presented in this study can potentially yield a wealth of new paleoceanographical proxies.

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Abstract: The history of grounded ice-sheet extent on the southern Weddell Sea shelf during the Last Glacial Maximum (LGM) and the timing of post-LGM ice-sheet retreat are poorly constrained. Several glaciological models reconstructed widespread grounding and major thickening of the Antarctic Ice Sheet in the Weddell Sea sector at the LGM. In contrast, recently published onshore data and modelling results concluded only very limited LGM-thickening of glaciers and ice streams feeding into the modern Filchner and Ronne ice shelves. These studies concluded that during the LGM ice shelves rather than grounded ice covered the Filchner and Ronne troughs, two deep palaeo-ice stream troughs eroded into the southern Weddell Sea shelf. Here we review previously published and unpublished marine geophysical and geological data from the southern Weddell Sea shelf. The stratigraphy and geometry of reflectors in acoustic sub-bottom profiles are similar to those from other West Antarctic palaeo-ice stream troughs, where grounded ice had advanced to the shelf break at the LGM. Numerous cores from the southern Weddell Sea shelf recovered sequences with properties typical for subglacially deposited tills or subglacially compacted sediments. These data sets give evidence that grounded ice had advanced across the shelf during the past, thereby grounding in even the deepest parts of the Filchner and Ronne troughs. Radiocarbon dates from glaciomarine sediments overlying the subglacial deposits are limited, but indicate that the ice grounding occurred at the LGM and that ice retreat started before ~15.1 corrected 14C kyrs before present (BP) on the outer shelf and before ~7.7 corrected 14C kyrs BP on the inner shelf, which is broadly synchronous with ice retreat in other Antarctic sectors. The apparent mismatch between the ice-sheet reconstructions from marine and terrestrial data can be attributed to ice streams with very low surface profiles (similar to those of "ice plains") that had advanced through Filchner Trough and Ronne Trough at the LGM. Considering the global sea-level lowstand of ~130 metres below present, a low surface slope of the expanded LGM-ice sheet in the southern Weddell Sea can reconcile grounding-line advance to the shelf break with limited thickening of glaciers and ice streams in the hinterland. This scenario implies that ice-sheet growth in the Weddell Sea sector during the LGM and ice-sheet drawdown throughout the last deglaciation could only have made minor contributions to the major global sea-level fluctuations during these times.

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Aims. We report results of an X-ray study of the supernova remnant (SNR) G344.7-0.1 and the point-like X-ray source located at the geometrical center of the SNR radio structure. Methods. The morphology and spectral properties of the remnant and the central X-ray point-like source were studied using data from the XMM-Newton and Chandra satellites. Archival radio data and infrared Spitzer observations at 8 and 24 mu m were used to compare and study its multi-band properties at different wavelengths. Results. The XMM-Newton and Chandra observations reveal that the overall X-ray emission of G344.7-0.1 is extended and correlates very well with regions of bright radio and infrared emission. The X-ray spectrum is dominated by prominent atomic emission lines. These characteristics suggest that the X-ray emission originated in a thin thermal plasma, whose radiation is represented well by a plane-parallel shock plasma model (PSHOCK). Our study favors the scenario in which G344.7-0.1 is a 6 x 10^3 year old SNR expanding in a medium with a high density gradient and is most likely encountering a molecular cloud on the western side. In addition, we report the discovery of a soft point-like X-ray source located at the geometrical center of the radio SNR structure. The object presents some characteristics of the so-called compact central objects (CCO). However, its neutral hydrogen absorption column (N_H) is inconsistent with that of the SNR. Coincident with the position of the source, we found infrared and optical objects with typical early-K star characteristics. The X-ray source may be a foreground star or the CCO associated with the SNR. If this latter possibility were confirmed, the point-like source would be the farthest CCO detected so far and the eighth member of the new population of isolated and weakly magnetized neutron stars.

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In order to test the sensitivity of marine primary productivity in the midlatitude open ocean North Atlantic to changes in the Atlantic Meridional Overturning Circulation (AMOC), we investigated two spliced sediment cores from a site south of the Azores Islands at the northern rim of the North Atlantic subtropical gyre. For this purpose we analyzed coccolithophore assemblages, diatom abundances, alkenones and conducted X-ray fluorescence (XRF) core scanning. During times of reduced AMOC, especially during Heinrich event 1 (H1) and the Younger Dryas, we observe a strong increase in productivity as evidenced by high coccolith accumulation rates, high alkenone concentrations/accumulation rates, high Ba/Ti-ratios, high abundances of diatoms and low abundances ofF. profunda. The increased productivity is partly caused by a more southern position of the Azores Front (AzF), and hence by a less northward extension of the subtropical gyre, as deduced from high abundances of the temperate coccolithophore species G. muellerae and low abundances of subtropical species (Oolithotus spp., Umbellosphaera spp., Umbilicosphaeraspp.). However, to explain the full range of the observed productivity increase, other factors like increased westerly winds and advection of nutrient-rich surface waters have also to be considered. Because this pattern can also be observed in other sediment cores from the midlatitude North Atlantic, we propose that during times of reduced AMOC there has been a band of strongly increased productivity across the North Atlantic at the northern rim of the contracted subtropical gyre, which partly counteracts the decreased organic carbon pump in the high northern latitudes.

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This thesis is a biographical examination of the life of Mohawk leader Deserontyou (Captain John) and covers the years from the 1730's up to, and briefly following, 1811. The social, economic and political position of the Mohawk people and Deserontyou's position within the Fort Hunter community prior to the Revolution are addressed first. The Revolutionary War years are then covered with emphasis placed on Deserontyou's military role, the unpleasant conditions at Lachine and the painful reality for the Mohawk people in the aftermath of Britain's defeat. The post-war settlement on the Bay of Quinte is then explored, including the difficulties that Deserontyou experienced with the land, with the British Government, and with his own people. The documents upon which this examination are based come from many primary collections including: The Draper Manuscripts, the Haldimand Papers, the Stuart Papers, Ontario Lands & Forest Survey Records, the Society for the Propagation of the Gospel in Foreign Parts, Episcopal Records, the Bell Papers, the File Collection, the Claus Papers and Indian Affairs Papers.