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Comportamento de prateleira de luz em modelo fisico sob ceu real na cidade de Campinas, SP / Behavior of light shelf in physical model under real sky in the city of Campinas, SPRosim, Camila Aldriguetti, Scarazzato, Paulo Sérgio, 1954- 12 August 2018 (has links)
Orientadores: Mauricio Roriz, Paulo Sergio Scarazzato / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-12T07:07:29Z (GMT). No. of bitstreams: 1
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Previous issue date: 2008 / Resumo: A utilização de iluminação natural, por meio de aberturas laterais é quase inevitável nas edificações. No entanto, da forma convencional como vêm sendo projetadas e construídas, estas aberturas podem apresentar desempenho bastante insatisfatório, particularmente em relação à má distribuição das iluminâncias internas e aos significativos níveis de ganhos térmicos. Esta Dissertação de Mestrado apresenta uma pesquisa que, através da análise de dados medidos em modelo físico, montado na cidade Campinas, Estado de São Paulo, objetivou identificar os parâmetros principais que interferem no comportamento de prateleiras de luz. Essas são elementos que redirecionam a luz solar para o interior dos ambientes, especialmente para as regiões mais distantes das janelas, muitas vezes insuficientemente iluminadas e que, ao mesmo tempo, atenuam o excesso de radiação nas regiões mais próximas das fachadas, reduzindo, assim, os contrastes entre áreas mais claras e mais escuras. O experimento foi realizado com monitoramento simultâneo de iluminâncias externas e internas ao modelo em escala, sob as condições reais do céu local. Foram estudados seis sistemas de prateleiras: branca horizontal, branca com quatro diferentes inclinações e espelhada horizontal. Foram elaboradas comparações entre os desempenhos apresentados por estas seis tipologias, bem como entre seus resultados e aqueles observados em sistemas tradicionais de aberturas laterais, sem qualquer elemento de redirecionamento da luz. Adicionalmente, os valores medidos foram também comparados com outros dados experimentais, disponíveis no software DLN - Disponibilidade de Luz Natural. / Abstract: The use of day lighting through lateral openings is almost inevitable in the constructions. However, in the conventional form as they come being projected and constructed, these openings present sufficiently unsatisfactory performance, particularly in relation to bad distribution of the internal luminance and to the significant levels of thermal profits. This work of graduate presents a research that, through the analysis of measured data in physical model mounted in the Campinas city, state of São Paulo, it objectified to identify the main parameters that intervene with the behavior of light shelves. These are elements that redirect the solar light for the interior of environments, especially for the regions most distant of the windows, many times insufficiently illuminated and that, in the same time, attenuate the excess of radiation in the regions next to the feats, thus reducing the contrasts between clearer and darker areas. The experiment was carried through with simultaneous watching of external and internal luminance to the model in scale, under the real conditions of the local sky. Six systems of shelves, horizontal white, white with four different inclinations and horizontal mirror surface had been studied. Had been elaborated comparisons between the performances presented for these six typologies, as well as between its results and the observed ones in traditional systems of lateral openings, without any element of redirectioning of the light. Additionally, the measured values also had been compared with other experimental data, available in software "DLN" - Availability of Natural Light. / Mestrado / Arquitetura e Construção / Mestre em Engenharia Civil
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Coating of pears (Var. ‘Packhams Triumph’) with kafirin protein and its effect on postharvest physiology and shelf-lifeBuchner, Sonya 24 February 2012 (has links)
In order to reduce postharvest losses of exported Pome fruit and increase export revenue, export quality pears require a reduction in stem-end shrivelling and an extension in shelf-life, regardless of the presence or absence of refrigerated storage. A kafirin coating may fulfil these requirements during export and at the export destination, in retail and at fresh fruit markets. A two-phased approach was followed. During Phase 1, the physiological and biochemical behaviour of ’Packham’s Triumph’ pears were studied under ideal refrigerated (-0.5°C), temperature-abused (10°C) and typical ripening (20°C) conditions. These storage conditions were selected to simulate potential conditions during the export process. Phase 2 involved the development and application of a kafirin-based coating to increase the shelf-life of pears. In Phase 1, two experiments were conducted concurrently on freshly harvested, uncoated pears. In Experiment 1, pears were stored at –0.5, 10 and 20°C and 95 to 98% RH for 42, 42 and 21 d respectively. An increase in storage temperature increased the metabolic activity of the pears and the rate of quality deterioration. Very few quality changes occurred in pears during storage at -0.5°C. Pears stored at 20°C ripened and became senescent in approximately half the time taken by pears at 10°C. However, fully ripe ‘Packham’s’ pears from 10 and 20°C exhibited similar final colour and firmness values. Stem-end shrivelling was exacerbated by storage at 20°C after only 4 days but not observed during storage at -0.5 or 10°C. In Experiment 2, ‘Packham’s Triumph’ pears were stored at -0.5 and 10°C (95 to 98% RH) for 42 and 35 days, respectively before being ripened at 20°C for 7 days. Storage of pears at 10°C prior to ripening accelerated softening and yellowing in the pears, when compared to pears from -0.5°C storage. Storage duration prior to ripening at 20°C also resulted in pears of increasing softness and yellowness by the end of 7 days at 20°C. The effect of storage duration at -0.5°C was less severe on the ripening rate and intensity of softening and yellowing than storage at 10°C. Thus, storage at -0.5°C extended pear shelf-life and resulted in pears of better quality after ripening than storage of pears at 10°C. In Phase 2, pears from Controlled Atmosphere (CA) storage were coated with a kafirin-based coating and stored at 20°C (35 to 45% RH) for 24 days. The ripening rate and the physiological behaviour and physico-chemical changes of pears used in Phase 2 were probably accelerated by 18 weeks under CA conditions and one week under RA conditions prior to the start of the shelf-life study. The kafirin coating did not retard ripening, which was probably already induced during storage before coating, but senescence in the coated pears was delayed by approximately 6 days. The rate of respiration, ethylene production, flesh softening and especially yellowing, was delayed by the coating. Coated and uncoated pears exhibited no growth of coliforms or lactic acid bacteria. Overall, coated pears had lower levels of aerobic mesophiles and yeast and mould growth than uncoated pears. Unfortunately, pear surface-shrivelling was intensified by the coating, probably due to the dehydrating action of the ethanol in the coating solution during dipping. However, the kafirin coating was able to extend pear shelf-life by delaying senescence and microbiological growth. The coating formulation may require a higher concentration of kafirin to increase its hydrophobicity and reduce pear shrivelling. The kafirin coating has possible potential to markedly extend the quality and shelf-life of ‘Packham’s Triumph’ pears, provided that the pears are coated after minimal RA storage when pears are in the pre-climacteric phase. Copyright 2007, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. Please cite as follows: Buchner, S 2007, Coating of pears (Var. ‘Packhams Triumph’) with kafirin protein and its effect on postharvest physiology and shelf-life, MSc(Agric) dissertation, University of Pretoria, Pretoria, viewed yymmdd < http://upetd.up.ac.za/thesis/available/etd-02242012-113144/ > E549/gm / Dissertation (MSc(Agric))--University of Pretoria, 2012. / Food Science / unrestricted
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Migration of <I>Penicillium spinulosum</I> from Paperboard Packaging to Extended Shelf Life MilkSammons, Laura Dawn 21 October 1999 (has links)
The growth and survival of the psychrotroph Penicillium spinulosum in paperboard was studied along with the wicking characteristics of ultra-pasteurized milk to understand sporadic fungal contamination of ultra-pasteurized, extended shelf life milk products. Previous research has indicated paperboard packaging as a potential source for the fungal contamination. Migration from paperboard to ultra-pasteurized skim milk during a 60-day shelf life, was investigated by inoculating condia (spores) into sterilized paperboard squares (57.2 by 57.2 mm) made from ultra-pasteurized milk cartons. Test-squares were sealed on three sides and inoculated at 3.2, 6.4, 9.5 and 12.7 mm from the uncoated (unskived) edge. The surrounding milk was tested for the presence of the fungus. Penicillium spinulosum was detected in 84% of samples at 3.2, 72% at 6.4, 50% at 9.5, and 28% at 12.7 mm from the uncoated edge. Survival in paperboard was investigated in sealed paperboard test-squares incubated in ultra-pasteurized skim milk at 7°C every 10 days up to 60 days. Penicillium spinulosum survived in the interior of paperboard for the entire incubation period. Survival was also measured on all test-squares for which P. spinulosum was not detected in the surrounding milk in the migration study. Penicillium spinulosum was detected in 94.4% of all negative samples. The wicking characteristics of ultra-pasteurized skim and whole milk were measured in four boards from gable-top cartons for ultra-pasteurized milk products. Test-squares were sealed on 3 sides and incubated in ultra-pasteurized skim or whole milk at 7°C. Wicking distances were measured every 10 days up to 60 days. A significant interaction was seen between the types of paperboard and milk. It is most likely that P. spinulosum at all inoculation distances had access to milk as a source of nutrition by day 40 in the migration study. / Master of Science
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Extending Saleable Shelf Life Of Selected Perishable Specialty CropsAl-badri, Samir B.Salman 01 May 2019 (has links) (PDF)
Farmers are limited in the amount of specialty crops they can plant, harvest and market without adequate cooling to preserve commodities before sale. A cooler available at a farm would allow the farmer to harvest his produce earlier and take it to market at a later time. Cooling available on the farm will help a farmer to harvest commodities during peak harvest times and store it for future sale at multiple farmers markets or over a period of a week or more at a farm market. A cooler will give a farmer more logistical options. An indirect-direct evaporative pad cooling can provide cooling with high humidity which is sufficient to prolong shelf life. A cool room with window air conditioning (AC) was modified by adding indirect-direct evaporative cooling. The cool room was used for comparative study of produce shelf life under AC (with CoolBot), indirect-direct evaporative cooling (EC), residential AC (RES), and farm building (FB) storage. Results showed that FB had a lower shelf life because of non-conditioned space. RES was a table in an office building with a temperature of about 22°C. For produce with medium temperature requirements such as tomato, cucumber, and green pepper the shelf life was prolonged more in the cooler room. Strawberry and blueberry had a much longer shelf life in a cooler. The shelf life of the blueberry stored at Cooler AC was longer about two and a half fold longer than Cooler EC and RES, and five and half fold longer than FB. The shelf life of the strawberry in Cooler AC was longer one-fold than Cooler EC, two and a half fold longer than RES, and five-fold longer than FB. The shelf life of green pepper stored in Cooler AC was longer fivefold than Cooler EC and nine and a half fold longer than RES and FB. The shelf life of cucumber stored at Cooler AC was longer two fold than Cooler EC and 3.3-fold longer than RES and four fold longer than FB. The shelf life of tomato stored at Cooler AC was longer 1.25-fold than Cooler EC, 1.75 fold longer than RES and two and a half fold longer than FB. Generally stored fruits and vegetables in Cooler AC was maintained quality with minimal weight loss that allows a farmer to store their produce while maintaining shelf life. Cooler EC can be used to store produce for a shorter time with higher weight loss. Finally, FB had a shorter shelf life due to the non-conditioned space.
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Harvest aids for improved bermudagrass sod shelf-life and transplantation successMinaev, Nikolay 07 August 2020 (has links)
Shelf-life and transplantation success of sodded and sprigged turfgrasses are negatively affected by disruptive harvest techniques and post-harvest handling/storage conditions. Air and light are limited inside of stacked pallets of sod or masses of sprigs/plugs, which triggers multiple processes that may lead to poor transplant success. Current research looks at the effects of several commercially available turfgrass products and cultural practices on post-harvest bermudagrass storage, its grow-in after transplantation, and harvested area recovery. Ensilation and internal heating sometimes observed in stored, full-sized pallets of sod were difficult to simulate in small-size sod masses. When storage environment and post-harvest conditions were controlled, refrigeration of stored bermudagrass slowed establishment, which is contrary to common knowledge and industry practice. Fluxapyroxad + pyraclostrobin fungicide positively affected turfgrass grow-in during field and greenhouse experiments, and in some instances hastened growth and recovery of bermudagrass.
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A Framework to Support the Development of Manually Adjustable Light Shelf TechnologiesJaved, Shamim 30 June 2014 (has links)
Active daylight harvesting technologies that are currently available in the market have often suffered from wide-spread market acceptability due to their high cost and imperfect performance. Passive systems, though simple and affordable, typically cannot harvest higher potentials of daylight, which is dynamic over days, months, and seasons, due to their static nature. There is a research and market gap that calls for investigation towards the development of low-tech, manually adjustable, high-performance daylighting mechanisms to be used as an alternative to active daylighting solutions, which are often controlled by building automation systems. This research proposes a framework to support the development of daylight harvesting mechanisms, which will allow for low-tech yet temporary adjustable systems, merging some of the advantages of active systems with passive ones. The hybrid of the above two categories will be a manually adjustable light harvesting device that will allow for quick adjustment through mechanical means to few predefined positions. These positions will be customized to each location to achieve optimum daylight harvesting. The resulting device will allow for flexible adjustment to daily and seasonal variations of the sun's path, while retaining a level of simplicity and elegance towards low-cost installation and operation.
Significant effort was made in the initial phase of this research to use experimental studies as the primary method of investigation. However, given the nature of daylight and practical constraints in the field, the experimental method was found to be not productive enough for extent of this research. As a result, simulation studies were ultimately used to generate the necessary data for the development of this framework. For the simulation phase 'DIVA4Rhino,' a climate-based daylighting software and 'Grasshopper,' a graphical programming tool for Rhino, was used to first construct a parametric simulation loop. Next, a reduced set of parameters for a manually adjustable light shelf system were tested for daylight performance, as a 'proof of concept'. Finally, based on the previous two steps, a framework to help the development of manually adjustable light shelf systems has been defined.
This research shows that light shelves, even when kept fixed at a single optimum configuration for the whole year, can increase interior daylight performance in most locations and orientations. It also shows that indoor daylight harvesting can be further enhanced if the light shelf is manually adjusted on a seasonal basis. Amongst the variations tested, rotational adjustability has been found to contribute most to the increase in performance. Segmented adjustability, e.g. where the inner and outer sections of a light shelf are manipulated separately, was found to extend performance of light shelves even further though not by significant amounts. / Ph. D.
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Structure and stratigraphy of an evolving salt ridge and basin complex, Louisiana continental shelfJohnson, Larry Chris 25 August 2011 (has links)
Utilizing 887 kilometers of multi-stacked seismic reflection profiles and data from 27 exploratory wells, five salt domes arranged along two intersecting salt ridges, bounding and separating localized depocenters , were delineated by subsurface mapping of the structure, sediment distribution, and major sand trends of a 1621 square kilometer area on the Louisiana continental shelf. Pervasive normal faulting in the study area developed to accommodate lengthening of sedimentary units resulting from relative vertical displacement caused by uneven deposition and salt dome growth. These faults are domal (crestal and radial), bounding, and transverse in geometry. The genesis of the bounding faults can be visualized by two models; hinge faulting and collapse faulting. The dominant structural features of the study area began developing in early Pliocene. These features developed coincident with, and as the result of, a huge influx of paralic sediments associated with the progradation of the shelf edge across the study area between early Pliocene and early Pleistocene. The two major dip-oriented sand trends within this sediment wedge represent high constructive delta systems. The positions of the two systems were locally controlled by growing salt structures and sediments were therefore concentrated in the evolving depocenters . A hint of the deep structure which predated the influx of paralic sediments in Pliocene and early Pleistocene is revealed by a structural reversal present on seismic profiles at about 4.0 seconds in the northwest part of the study area. Reconstruction of the paleostructure of this area reveals the flank of an ancestral structural and stratigraphic basin. This basin may represent an ancestral depocenter which began developing very early on the abyssal plain. / text
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Sources and transport of late Quaternary sediments, Karlsefni Trough, Labrador ShelfVeldhuyzen, Hendrik. January 1981 (has links)
No description available.
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Organic matter preservation along a dynamic continental margin : form and fates of sedimentary organic matter /Nuwer, Jonathan Mark. January 2008 (has links)
Thesis (Ph. D.)--University of Washington, 2008. / Vita. Includes bibliographical references (leaves 156-175).
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Interannual flows along Australia's western and southern coasts and along the northern coast of the Gulf of MexicoLi, Jianke. Clarke, Allan J. January 2004 (has links)
Thesis (Ph. D.)--Florida State University, 2004. / Advisor: Dr. Allan J Clarke, Florida State University, College of Arts and Sciences, Dept. of Oceanography. Title and description from dissertation home page (Jan. 13, 2005). Includes bibliographical references.
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