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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.
411

The influence of the packaging material on the mechanical properties of carrot tissue during storage.

Mohammed, Hakim January 1976 (has links)
No description available.
412

Simple Digital Libraries

Phiri, Lighton 01 August 2013 (has links)
The design of Digital Library Systems (DLSes) has evolved overtime, both in sophistication and complexity, to complement the complex nature and sheer size of digital content being curated. However, there is also a growing demand from content curators, with relatively small-size collections, for simpler and more manageable tools and services to manage their content. The reasons for this particular need are driven by the assumption that simplicity and manageability might ultimately translate to lower costs of maintenance of such systems. This research proposes and advocates for a minimalist and simplistic approach to the overall design of DLSes. It is hypothesised that Digital Library (DL) tools and services based on such designs could potentially be easy to use and manage. A meta-analysis of existing DL and non-DL tools was conducted to aid the derivation of design principles for simple DLSes. The desig n principles were then mapped to design decisions applied to the design of a prototype simple repository. In order to assess the effectiveness of the simple repository design, two real-world case study collections were implemented based on the design. In addition, a developer-oriented study was conducted using one of the case study collections to evaluate the simplicity and ease of use of the prototype system. Furthermore, performance experiments were conducted to establish the extent to which such a simple design approach would scale and also establish comparative advantages to existing designs. In general, the study outlined some possible implications of simplifying DLS design; specifically the results from the developer-oriented user study indicate that simplicity in the design of the DLS repository sub-layer does not severely impact the interaction between the service sub-layer and the repository sub-layer. Furthermore, the scalability experiments indicate that desirable performance results for small- and medium-sized collections are attainable. The practical implication of the proposed design approach is two-fold: firstly the minimalistic design has the potential to be used to design simple and yet easy to use tools with comparable features to those exhibited by well-established DL tools; and secondly, the principled design approach has the potential to be applied to the design of non-DL application domains.
413

Effect of storage pre-treatments and conditions on the dehulling efficiency and cooking quality of red lentils

Alejo Lucas, Daniella 07 May 2010 (has links)
This study focuses on investigating the effect of post-harvest handling conditions and storage time on the dehulling efficiency and cooking quality of two varieties of red lentils, as well as optimizing the dehulling conditions. The effects of storage time, storage moisture content and storage temperature, as well as the effect of different storage pre-treatments aiming to simulate post-harvest handling, were studied. Dehulling efficiency was mostly affected by the pre-milling moisture content, regardless of the storage conditions. Pre-treatments involving moisture content changes lowered the dehulling efficiency of both varieties of red lentils, whereas freezing and thawing cycles had less of a negative effect on the dehulling characteristics. Textural parameters were mostly affected by storage time; samples became harder after storage. The final recommendation arising from this study is to monitor the moisture content of lentils during storage as it has a detrimental effect on both the dehulling and cooking quality.
414

Human milk storage conditions in regard to safety and optimal preservation of nutritional properties

Abramovich, Milana 17 January 2011 (has links)
This study assessed losses of the linoleic, alpha-linolenic, arachidonic and docosahexaenoic fatty acids, vitamin B2 and total vitamin C during storage of human milk, pasteurized and unpasteurized. The volatile compounds’ pattern change was monitored. The storage conditions were 8 days at 4oC and 6 months at -20oC and at -80oC, with and without limitation of oxygen. Fatty acids were analyzed by GC-FID; vitamins - by HPLC; volatile compounds’ concentration patterns were obtained using the e-nose machine; ANOVA tests were applied, with the statistical significance assigned to P<0.05. The official recommendations for human milk storage of 5-8 days at 4oC and of 6 or more months at -20oC are appropriate in regard to the analyzed nutrients and can be extended for pasteurized human milk storage. Oxygen limitation and -80oC temperature have no clear benefit for nutrient preservation. The evaluation of the odour cannot be based exclusively on the e-nose analysis.
415

A guide for the use of the textile information system.

Butterworth, Joanne January 1964 (has links)
No description available.
416

Robust multitrack modulation codes for the storage channel

Lee, Jaejin 12 1900 (has links)
No description available.
417

Casem--A system for computer aided selection of engineering materials

Divitci, Nezih Vefik 05 1900 (has links)
No description available.
418

CO2 interaction with aquifer and seal on geological timescales : the Miller oilfield, UK North Sea

Lu, Jiemin January 2008 (has links)
Carbon Capture and Storage (CCS) has been identified as a feasible technology to reduce CO2 emissions whilst permitting the continued use of fossil fuels. Injected CO2 must remain efficiently isolated from the atmosphere on a timescale of the order of 10000 years and greater. Natural CO2-rich sites can be investigated to understand the behaviour of CO2 in geological formations on such a timescale. This thesis examines the reservoir and seal on one such oilfield. Several hydrocarbon fields in the South Viking Graben of the North Sea naturally contain CO2, which is thought to have charged from depth along the western boundary fault of the graben. The Miller oil field which contains ~ 28 mol% CO2, of isotopic composition δ13C = -8.2‰. The Upper Jurassic Brae Formation reservoir sandstones and the Kimmeridge Clay Formation (KCF) seal have been exposed to the CO2 accumulation since its emplacement. Rock samples from the reservoir sandstone and bottom of the seal mudrock were examined using multiple techniques, including XRD, SEM, fluid inclusion and carbonate stable isotope analyses. The sandstones show no features directly attributable to abundant CO2 charge. SEM analyses reveal significant heterogeneities in diagenesis within the KCF. The silt/sand lithologies of the KCF have undergone a diagenetic history similar to that of the Brae Formation sandstones. In contrast, the KCF shales display a distinctly different diagenesis of dominant dissolution of quartz and feldspar with little evidence of mineral precipitation. In both the Brae Formation and the KCF, pore-filling kaolinite, illite and carbonates are relatively late diagenetic events which can be associated with CO2-induced feldspar dissolution. Mudrock X-ray diffraction mineralogical data reveal abrupt vertical mineralogical variations across the reservoir crest in the Miller Field, while such variations are absent in a low-CO2 control well in the same geological settings. This suggests that reactions induced by abundant CO2 dissolved feldspar and produced kaolinite, carbonates and quartz in the seal, while oil emplacement inhibited the reactions in the oil leg. However, petrographic evidence and comparison between different sections argue against CO2 reactions as the sole cause for such large mineralogical variations, especially for quartz. The vertical mineralogical variations to a certain extend represent original sedimentary heterogeneity. Linear variations of carbonate δ13C with depth were discovered in both shale and silt/sand lithologies of the KCF in a 12m zone immediately above the reservoir. These features are absent in the low-CO2 control well. These trends are interpreted as dissolution of original carbonates by CO2 slowly ascending from the reservoir. New carbonates precipitated from a carbon source with upwards decreasing δ13C due to mixing between three carbon sources with different C isotopes at systematically varying ratios. The isotopes in the reservoir and the bottom of the seal suggests initial CO2 charge at about 70-80 Ma. CO2 infiltration rate is estimated at about 9.8×10-7g·cm-2·y-1. Geochemical modelling was applied to reconstruct the reservoir fluid evolution by calibrating it to mineralogy, fluid chemistry, diagenesis and fluid inclusion data. The modelling suggests that CO2 migrated into the reservoir together with a saline basinal fluid derived from the underlying evaporites at ~ 70 Ma. The CO2 and basinal water charge imposed an important influence on the mineral reactions and fluid chemistry. This study suggests that the KCF has formed an excellent CO2 seal, with no substantial breach since its charge at 70-80 Ma.
419

Increasing Optical Disc Data Density by Using Nano-scale Metallic Wire Polarisers

Chin, Allan January 2006 (has links)
CD and DVD became the major portable and backup data storage devices because their reliability and economical cost when mass produced. As the computer technology grew, higher data storage density on CD/DVD disc was demanded. Using a shorter wavelength light source was the common technique to achieve this goal from both research and industry. However, the limit of wavelength had almost reached for applying it to optical storage. The nano-scale metallic wire polariser that was designed in this thesis provided a possible solution. This thesis introduces the method of using the nano-scale metallic wires to form a grating polariser as the data pit on CD/DVD disc. The polariser is a type of scattering polariser and could transmit one linear polarisation of the light and reject its orthogonal counter part. The designed pattern was tested by using XFDTD, an electromagnetic simulation program based on the finite difference time domain method. As the wave source was a red laser with a wavelength of 650nm, the simulation cell size was set to be 10nm. The dispersive materials were simulated by the Debye model. The electric field results were measured on X, Y, and Z components. The results were analysed by a pre-written Matlab program to find the transmission and crosstalk coefficients. The single polariser simulations showed that there are great potentials in this design. However, inter-cell crosstalk became the major problem in the polariser array simulations. The groove pattern and titanium material were used to optimise the polarisation effect. The simulation showed that a standard-sized disc with a titanium polariser array could have 5.5GB storage capacity and a 15 to 20dB inter-cell extinction ratio for an optical pickup with a red laser (650nm) and a numerical aperture (NA) of 0.6. Although the improvement is only marginal over existing optical data storage technology, there are many further researches possible to carry on such as the fabrication of the polariser arrays.
420

The effect of low temperature on Salmonella

Phillips, Lisa Elaine January 1999 (has links)
No description available.

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